This document provides an outline for a course on Engineering Surveying II taught by Prof. Dr.-Ing. John Bosco Kyalo Kiema at the University of Nairobi. The course covers topics such as horizontal control through traversing, vertical control through leveling, applications to highway drainage and earthworks, and practical field surveying. Assessment includes exams, coursework, and a term paper on the role of geoinformatics in environmental monitoring and management. The lecture outline provides details on traversing, vertical control, earthworks computations, and references textbooks on surveying.
The document discusses precise leveling, including its aims, concepts, history in Malaysia, equipment, and types. Precise leveling is needed to establish accurate height networks and transfer heights precisely for engineering works. It requires specialized optical, motorized, or digital leveling instruments and invar staffs read to millimeters. Malaysia's first vertical datum was established in 1912, and its current tidal network helps define an accurate national geodetic vertical datum.
12.1. Horizontal and vertical control (1).pptxSaddoAjmal
This document provides an overview of engineering surveying topics including construction surveying, horizontal and vertical controls, and their application to various construction projects such as buildings, railroads, pipelines, and underground mining. It discusses the history of surveying, key elements and stages of construction surveying, and methods for establishing horizontal and vertical control networks to guide construction activities. Specific surveying techniques are described for setting out buildings, laying railroads, constructing pipelines, and surveying underground mines.
This document provides information about tacheometry, which is a method of surveying that determines horizontal and vertical distances from instrumental observations. It discusses how tacheometry can be used when obstacles make traditional surveying difficult. The key aspects covered include:
- Defining tacheometry and the measurements it provides
- When tacheometry is advantageous over other surveying methods
- The instruments used, including tacheometers and levelling rods
- How horizontal and vertical distances are calculated using constants
- The different types of tacheometer diaphragms and telescopes
- The fixed hair method for taking readings
This document discusses triangulation, which is a surveying technique used to establish horizontal control networks over large areas. It involves measuring angles and lengths within networks of triangles. There are different orders of triangulation based on accuracy and area covered, including primary, secondary, and tertiary triangulation. Key aspects discussed include triangulation station layout and design, angle and distance measurements, controlling errors, and computation of unknown lengths and directions within triangles.
The document provides information about theodolite surveying including:
1. A theodolite is an instrument used to measure horizontal and vertical angles which can also be used to prolong lines, measure distances indirectly, and for leveling.
2. Theodolite traversing involves establishing control points by measuring angles and distances between traverse stations to calculate positions.
3. Components of a theodolite include a telescope that can rotate vertically and a compass to determine direction, along with accessories like a tripod, rods, and tapes used in surveying.
Course Contents:
Introduction; Linear measurements; Analysis and adjustment of measurements, Survey methods: coordinate systems, bearings, horizontal control, traversing, triangulation, detail surveying; Orientation and position; Areas and volumes; Setting out; Curve ranging; Global Positioning system (GPS); Photogrammetry.
1) Levelling is the process of determining the relative elevations of points on or near the earth's surface. It is important for engineering projects to determine elevations along alignments.
2) Levelling is used to prepare contour maps, determine altitudes, and create longitudinal and cross sections needed for projects.
3) Key terms include bench mark, datum, reduced level, line of collimation, and height of instrument. Different types of levelling include simple, differential, fly, longitudinal, and cross-sectional levelling.
The document discusses precise leveling, including its aims, concepts, history in Malaysia, equipment, and types. Precise leveling is needed to establish accurate height networks and transfer heights precisely for engineering works. It requires specialized optical, motorized, or digital leveling instruments and invar staffs read to millimeters. Malaysia's first vertical datum was established in 1912, and its current tidal network helps define an accurate national geodetic vertical datum.
12.1. Horizontal and vertical control (1).pptxSaddoAjmal
This document provides an overview of engineering surveying topics including construction surveying, horizontal and vertical controls, and their application to various construction projects such as buildings, railroads, pipelines, and underground mining. It discusses the history of surveying, key elements and stages of construction surveying, and methods for establishing horizontal and vertical control networks to guide construction activities. Specific surveying techniques are described for setting out buildings, laying railroads, constructing pipelines, and surveying underground mines.
This document provides information about tacheometry, which is a method of surveying that determines horizontal and vertical distances from instrumental observations. It discusses how tacheometry can be used when obstacles make traditional surveying difficult. The key aspects covered include:
- Defining tacheometry and the measurements it provides
- When tacheometry is advantageous over other surveying methods
- The instruments used, including tacheometers and levelling rods
- How horizontal and vertical distances are calculated using constants
- The different types of tacheometer diaphragms and telescopes
- The fixed hair method for taking readings
This document discusses triangulation, which is a surveying technique used to establish horizontal control networks over large areas. It involves measuring angles and lengths within networks of triangles. There are different orders of triangulation based on accuracy and area covered, including primary, secondary, and tertiary triangulation. Key aspects discussed include triangulation station layout and design, angle and distance measurements, controlling errors, and computation of unknown lengths and directions within triangles.
The document provides information about theodolite surveying including:
1. A theodolite is an instrument used to measure horizontal and vertical angles which can also be used to prolong lines, measure distances indirectly, and for leveling.
2. Theodolite traversing involves establishing control points by measuring angles and distances between traverse stations to calculate positions.
3. Components of a theodolite include a telescope that can rotate vertically and a compass to determine direction, along with accessories like a tripod, rods, and tapes used in surveying.
Course Contents:
Introduction; Linear measurements; Analysis and adjustment of measurements, Survey methods: coordinate systems, bearings, horizontal control, traversing, triangulation, detail surveying; Orientation and position; Areas and volumes; Setting out; Curve ranging; Global Positioning system (GPS); Photogrammetry.
1) Levelling is the process of determining the relative elevations of points on or near the earth's surface. It is important for engineering projects to determine elevations along alignments.
2) Levelling is used to prepare contour maps, determine altitudes, and create longitudinal and cross sections needed for projects.
3) Key terms include bench mark, datum, reduced level, line of collimation, and height of instrument. Different types of levelling include simple, differential, fly, longitudinal, and cross-sectional levelling.
surveying Engineering
Fly Levelling
Fly leveling: -Fly leveling is just like differential leveling carried
out to check the accuracy of leveling work. It is a very approximate
form of leveling in which sights are taken as large as possible. in this
method, a line of levels is run to determine approximately reduced
levels of the points carried out with more rapidly and less precision
The aim of fly Levelling: The main purpose of this type of leveling is
to check the values of the reduced levels of the bench marks already
fixed. In this method only back sight and foresight are taken. There is no need of intermediate sights. However great care has to be taken for selecting the change points (Turning Points) and for taking reading on the change points because the accuracy of leveling depends upon these
-Create Bench Marks (BM).
Bench Marks
Bench Mark is a point of known elevation, there are three Type of Bench Marks
1-Perment Bench Mark.
2-Orbitrary Bench Mark .
3-Temporary Bench Mark .
-Leveling Process Calculation.
1. Height of collimation method
2. Rise and Fall method
How do we find horizontal distance using levelling Machine.
Fly Levelling Close loop survey.
Fly and Differential leveling Using (Rise & fall) and (HI)methods.
*Checks for Errors
-Misclosure
Allowable closing error
Where:
D =Distance in km
E = Misclosure error in (mm).
C = 30 for fixed levelling process in rough ground.
C = 15 for normal leveling in flat area (Good work)
Fly Levelling example
Computation of Elevations for an open loop survey H.I method
Computation of Elevations
Differential Leveling
Computation of Elevations
-Correction For Errors in Leveling
1. Errors Due to the line of sight being not horizontal
2. Error Due to Curvature and refraction.
Errors in differential leveling: -
1) Non adjustment of the instrument: -
a) Adjustment of cross-wire ring
b) Adjustment of the bubble tube
c) Adjustment of line of sight
2-Errors in levelling
• Collimation line
• Parallax
• Change point instability
• Instrument instability
• Benchmark instability
• Staff reading errors , • Staff verticality • Level Instrument shading • Temperature on staff • Booking errors) • Earth curvature • Refraction • The Bubble not center.
3-Constant error (instrumental error):
A. Non vertically of the staff.
B. Collimation error in the instrument.
C. Staff gradation error.
4- Random error (natural error):
A. Effect of wind and temperature.
B. Soft and hard ground.
C. Change points. CP
D. Human deficiencies and neglect
Prepared by:
Asst. Prof. Salar K.Hussein
Mr. Kamal Y.Abdullah
Asst.Lecturer. Dilveen H. Omar
Erbil Polytechnic University
Technical Engineering College
Civil Engineering Department
This document discusses several types of setting out works including:
1. Setting out a foundation plan using a center line plan and batter boards. Batter boards are used to accurately transfer the center line onto the work site.
2. Setting out a sewer line by fixing stakes along the proposed center line and excavating the trench to the desired width and depth. Cross heads and sight rails are also used to maintain proper gradient and alignment.
3. Setting out a culvert involves marking points along the center lines X1 and Y1 based on given distances from the origin point O. Pegs are placed at the intersection of the points using two tapes held at equal distances between assistants. The culvert is then set
This document is a field report for a traversing survey conducted by students. It contains unadjusted and average field data from three separate traverses, including measured horizontal and vertical angles between stations. It also shows the calculations to determine angular errors, angle adjustments, course bearings, latitudes and departures, adjusted coordinates, and station positions. The objectives, equipment used, and results are presented in tables and graphs.
This presentation discusses scales used in photographs. It explains that scale is the ratio of an object's size in a photo to its actual size on the ground. Scale can be expressed through a unit equivalent, representative fraction, or ratio. Knowing the camera focal length and aircraft altitude allows one to determine the scale of a vertical photograph. The presentation was given by Mr. Amol V. Ghogare of SRES, SCOE, Kopargaon on the topic of scales used in photographs.
Edm is a surveying instrument used to measure the distance electronically. This Surveying Instrument is used in triangulation to measure the length of Base line because more accuracy is required to measure the length of base line.
This document provides an overview of field astronomy concepts. It defines key celestial coordinate systems used to specify the position of heavenly bodies, including the horizon system (using altitude and azimuth), independent equatorial system (using right ascension and declination), and dependent equatorial system (using declination and hour angle). It also describes the celestial latitude and longitude system. Spherical trigonometry formulas are presented for computing angles and distances on the celestial sphere. The astronomical triangle relating altitude, declination, and latitude is illustrated. Key terms like latitude, longitude, declination, and right ascension are defined.
1) Curves are gradual bends provided in transportation infrastructure like roads, railways and canals to allow for a smooth change in direction or grade.
2) There are two main types of curves - horizontal curves which provide a gradual change in direction, and vertical curves which provide a gradual change in grade.
3) Curves are needed to safely guide vehicles and traffic when changing directions or grades, to improve visibility, and to prevent erosion of canal banks from water pressure.
The document defines levelling as determining the relative heights of points. It discusses the principle of obtaining a horizontal line of sight and objectives of finding point elevations and establishing points at required elevations. Different types of levels, staffs, benchmarks, and adjustments are described. Various levelling classifications are defined including simple, differential, profile, check, reciprocal and precise levelling. The key principle of levelling is to obtain a horizontal line of sight to measure staff readings and determine reduced levels of points.
This document provides an overview of basic surveying principles and methods:
1) Surveying works from establishing overall control points before measuring details. Control points are established through precise primary networks of triangles or traverses.
2) Secondary control networks further divide the primary network for less precise work. Survey of details then uses the established control points. This minimizes error accumulation.
3) A traverse connects lines whose lengths and directions are measured to establish a framework. Traverses can be open or closed, with closed traverses returning to the starting point.
4) The direction of lines is defined by their bearing from a reference meridian using different systems like true, magnetic, or arbitrary meridians.
Surveying Engineering
Traversing Practical part 1
Plane and Applied surveying 2
Report number(2)
• Report name :Gales Traverse Table(Horizontal angle
measurement (FL)of closed traversing
• Apparatus
• Theodolite Instrument
• Tripod
• Compass
• Pin
• Tape
• Range pole
Object
• To conducted survey work in a closed traversing and calculate
in depend coordinates and area calculation by coordinate rule.
Procedure Traverse;
Calculations Traverse .Dada Sheet and Table method work clock wise surveying
-Gales Traverse Table.
*Traverse Calculations
-Traverse Calculation.
-Coordinate conversions.
-Signs of Departures and Latitudes.
*Balancing latitude and departure
-Correction for ∆E& ∆N:
Bowditch adjustment or compass method
-The example…
-Vector components (pre-adjustment)
*The adjustment components
Prepared by:
Asst. Prof. Salar K.Hussein
Mr. Kamal Y.Abdullah
Asst.Lecturer. Dilveen H. Omar
Erbil Polytechnic University
Technical Engineering College
Civil Engineering Department
Electronic Distance Measurement (EDM) uses electromagnetic waves like light or radio waves to measure distances. EDM instruments transmit a signal that bounces off a reflecting prism and returns to the instrument. The distance is calculated based on the time it takes for the signal to return. EDM has largely replaced tape measurements and improved surveying efficiency. Modern EDM instruments are integrated into total stations and can measure slope distances with millimeter accuracy over several kilometers.
Chapter 6 area & volume measurement, Digital PlanimeterAbhay Abhale
This document discusses the components, uses, and measurement process of a digital planimeter. It describes the main components of a digital planimeter which include a roller, tracing arm, tracing magnifier, tracing point, and function keys. It then explains the various function keys and their purposes. Finally, it outlines the step-by-step process for measuring the area of a shape using a digital planimeter, which involves selecting a scale, marking a starting point, tracing the outline while holding the tracing point, and reading the area measurement from the display.
The document discusses different types of traverses and methods for conducting traverse surveys. It describes two types of traverses: open traverses that begin and end at points of known and unknown positions, and closed traverses that begin and end at points of known positions, including closed-loop traverses that begin and end at the same point. It also outlines four methods for determining directions during traversing: chain angle method, free needle method, fast needle method, and measuring angles between lines. Finally, it discusses instruments used for measuring angles like compasses and theodolites, and defines different types of bearings including true, magnetic, and arbitrary bearings.
Leveling is a surveying technique used to determine differences in elevation between points. It involves measuring vertical angles and distances to establish spot elevations across an area. There are two main methods - direct and indirect. Direct contouring involves marking points along contour lines in the field, while indirect contouring uses spot elevations from which contours are interpolated on a map. Common techniques include using a level, staff, and plane table or theodolite to obtain elevations and positions of points, which are then contoured. Leveling is important for engineering projects to design facilities and earthworks efficiently based on terrain.
*Introduction
*Controls For Setting Out
*Horizontal control
*Vertical control
*SETTING OUT A BUILDING
*The equipment required for the job
*Method(1):-By using a Circumscribing Rectangle
*Method(2):- By using centre-line-rectangle
* Setting out of culverts
*SETTING OUT A TUNNEL
This document provides information about circular curves used in highways and railways. It discusses the different types of curves including simple, compound, and reverse curves. It defines key elements of circular curves such as radius, deflection angle, tangent length, and mid-ordinate. It presents the relationships between radius and degree of curvature. Finally, it describes various methods for setting out circular curves in the field, including linear methods using offsets and angular methods using a theodolite.
This document provides an overview of hydrographic surveying. It defines key terms like hydrography, soundings, and horizontal and vertical controls. It describes common equipment used for hydrographic surveys like sounding boats, poles, lead lines, sounding machines, and echo sounders. It explains methods for locating soundings, such as using a cross rope, ranges and time intervals, or ranges with angular observations from shore or boat. The goal of hydrographic surveying is to accurately map bodies of water by taking depth measurements and positioning them spatially.
Surveying for Civil engineering is a
particular type of surveying known as "land surveying", it is the
detailed study or inspection, as by gathering information through
observations, measurements in the field, questionnaires, or
research of legal instruments, and data analysis in the support of
planning, designing, and establishing of property boundaries.
Land surveying can include associated services such as mapping
and related data accumulation, construction layout surveys,
precision measurements of length, angle, elevation, area, and
volume, as well as horizontal and vertical control surveys, and
the analysis and utilization of land survey data. Surveyors use
various tools to do their work successfully and accurately, such
as total stations, robotic total stations, GPS receivers, prisms, 3D
scanners, radio communicators, handheld tablets, digital levels,
and surveying software.
Survey data can be directly entered into a GIS from digital
data collection systems on survey instruments. When data is
captured, the user should consider if the data should be captured
with either a relative accuracy or absolute accuracy, since this
could not only influence how information will be interpreted but
also the cost of data captured.
In this paper GIS maps were developed depending on the
field surveying data made for a two traverses. First one has ribs
less than 50m length and the other larger than 50m. Each
traverse is holding five times using five equipments and
instruments: Tape, Level, Digital level, Digital theodolite and
Laser tape. Also those maps were drawn by using both of ACAD
and ArcView softwares. Then a detail surveying map was
produced. The precision was computed for both traverses in each
method. Its value is range from 1/140 to 1/10000.
This document discusses traverse surveys which involve measuring angles and distances between survey points to determine their positions. It provides the objective of traverse surveys which is to find accurate positions of stations to serve as control points for mapping or construction layout. The results section shows the distances, angles, coordinate calculations and adjustments for a sample 4-point traverse with a closure of 0. The discussion explains the traverse calculations and adjustments to distribute errors. The conclusion states that traverse surveys are commonly used for construction site layout and boundary surveys, and errors can be adjusted or the survey repeated.
surveying Engineering
Fly Levelling
Fly leveling: -Fly leveling is just like differential leveling carried
out to check the accuracy of leveling work. It is a very approximate
form of leveling in which sights are taken as large as possible. in this
method, a line of levels is run to determine approximately reduced
levels of the points carried out with more rapidly and less precision
The aim of fly Levelling: The main purpose of this type of leveling is
to check the values of the reduced levels of the bench marks already
fixed. In this method only back sight and foresight are taken. There is no need of intermediate sights. However great care has to be taken for selecting the change points (Turning Points) and for taking reading on the change points because the accuracy of leveling depends upon these
-Create Bench Marks (BM).
Bench Marks
Bench Mark is a point of known elevation, there are three Type of Bench Marks
1-Perment Bench Mark.
2-Orbitrary Bench Mark .
3-Temporary Bench Mark .
-Leveling Process Calculation.
1. Height of collimation method
2. Rise and Fall method
How do we find horizontal distance using levelling Machine.
Fly Levelling Close loop survey.
Fly and Differential leveling Using (Rise & fall) and (HI)methods.
*Checks for Errors
-Misclosure
Allowable closing error
Where:
D =Distance in km
E = Misclosure error in (mm).
C = 30 for fixed levelling process in rough ground.
C = 15 for normal leveling in flat area (Good work)
Fly Levelling example
Computation of Elevations for an open loop survey H.I method
Computation of Elevations
Differential Leveling
Computation of Elevations
-Correction For Errors in Leveling
1. Errors Due to the line of sight being not horizontal
2. Error Due to Curvature and refraction.
Errors in differential leveling: -
1) Non adjustment of the instrument: -
a) Adjustment of cross-wire ring
b) Adjustment of the bubble tube
c) Adjustment of line of sight
2-Errors in levelling
• Collimation line
• Parallax
• Change point instability
• Instrument instability
• Benchmark instability
• Staff reading errors , • Staff verticality • Level Instrument shading • Temperature on staff • Booking errors) • Earth curvature • Refraction • The Bubble not center.
3-Constant error (instrumental error):
A. Non vertically of the staff.
B. Collimation error in the instrument.
C. Staff gradation error.
4- Random error (natural error):
A. Effect of wind and temperature.
B. Soft and hard ground.
C. Change points. CP
D. Human deficiencies and neglect
Prepared by:
Asst. Prof. Salar K.Hussein
Mr. Kamal Y.Abdullah
Asst.Lecturer. Dilveen H. Omar
Erbil Polytechnic University
Technical Engineering College
Civil Engineering Department
This document discusses several types of setting out works including:
1. Setting out a foundation plan using a center line plan and batter boards. Batter boards are used to accurately transfer the center line onto the work site.
2. Setting out a sewer line by fixing stakes along the proposed center line and excavating the trench to the desired width and depth. Cross heads and sight rails are also used to maintain proper gradient and alignment.
3. Setting out a culvert involves marking points along the center lines X1 and Y1 based on given distances from the origin point O. Pegs are placed at the intersection of the points using two tapes held at equal distances between assistants. The culvert is then set
This document is a field report for a traversing survey conducted by students. It contains unadjusted and average field data from three separate traverses, including measured horizontal and vertical angles between stations. It also shows the calculations to determine angular errors, angle adjustments, course bearings, latitudes and departures, adjusted coordinates, and station positions. The objectives, equipment used, and results are presented in tables and graphs.
This presentation discusses scales used in photographs. It explains that scale is the ratio of an object's size in a photo to its actual size on the ground. Scale can be expressed through a unit equivalent, representative fraction, or ratio. Knowing the camera focal length and aircraft altitude allows one to determine the scale of a vertical photograph. The presentation was given by Mr. Amol V. Ghogare of SRES, SCOE, Kopargaon on the topic of scales used in photographs.
Edm is a surveying instrument used to measure the distance electronically. This Surveying Instrument is used in triangulation to measure the length of Base line because more accuracy is required to measure the length of base line.
This document provides an overview of field astronomy concepts. It defines key celestial coordinate systems used to specify the position of heavenly bodies, including the horizon system (using altitude and azimuth), independent equatorial system (using right ascension and declination), and dependent equatorial system (using declination and hour angle). It also describes the celestial latitude and longitude system. Spherical trigonometry formulas are presented for computing angles and distances on the celestial sphere. The astronomical triangle relating altitude, declination, and latitude is illustrated. Key terms like latitude, longitude, declination, and right ascension are defined.
1) Curves are gradual bends provided in transportation infrastructure like roads, railways and canals to allow for a smooth change in direction or grade.
2) There are two main types of curves - horizontal curves which provide a gradual change in direction, and vertical curves which provide a gradual change in grade.
3) Curves are needed to safely guide vehicles and traffic when changing directions or grades, to improve visibility, and to prevent erosion of canal banks from water pressure.
The document defines levelling as determining the relative heights of points. It discusses the principle of obtaining a horizontal line of sight and objectives of finding point elevations and establishing points at required elevations. Different types of levels, staffs, benchmarks, and adjustments are described. Various levelling classifications are defined including simple, differential, profile, check, reciprocal and precise levelling. The key principle of levelling is to obtain a horizontal line of sight to measure staff readings and determine reduced levels of points.
This document provides an overview of basic surveying principles and methods:
1) Surveying works from establishing overall control points before measuring details. Control points are established through precise primary networks of triangles or traverses.
2) Secondary control networks further divide the primary network for less precise work. Survey of details then uses the established control points. This minimizes error accumulation.
3) A traverse connects lines whose lengths and directions are measured to establish a framework. Traverses can be open or closed, with closed traverses returning to the starting point.
4) The direction of lines is defined by their bearing from a reference meridian using different systems like true, magnetic, or arbitrary meridians.
Surveying Engineering
Traversing Practical part 1
Plane and Applied surveying 2
Report number(2)
• Report name :Gales Traverse Table(Horizontal angle
measurement (FL)of closed traversing
• Apparatus
• Theodolite Instrument
• Tripod
• Compass
• Pin
• Tape
• Range pole
Object
• To conducted survey work in a closed traversing and calculate
in depend coordinates and area calculation by coordinate rule.
Procedure Traverse;
Calculations Traverse .Dada Sheet and Table method work clock wise surveying
-Gales Traverse Table.
*Traverse Calculations
-Traverse Calculation.
-Coordinate conversions.
-Signs of Departures and Latitudes.
*Balancing latitude and departure
-Correction for ∆E& ∆N:
Bowditch adjustment or compass method
-The example…
-Vector components (pre-adjustment)
*The adjustment components
Prepared by:
Asst. Prof. Salar K.Hussein
Mr. Kamal Y.Abdullah
Asst.Lecturer. Dilveen H. Omar
Erbil Polytechnic University
Technical Engineering College
Civil Engineering Department
Electronic Distance Measurement (EDM) uses electromagnetic waves like light or radio waves to measure distances. EDM instruments transmit a signal that bounces off a reflecting prism and returns to the instrument. The distance is calculated based on the time it takes for the signal to return. EDM has largely replaced tape measurements and improved surveying efficiency. Modern EDM instruments are integrated into total stations and can measure slope distances with millimeter accuracy over several kilometers.
Chapter 6 area & volume measurement, Digital PlanimeterAbhay Abhale
This document discusses the components, uses, and measurement process of a digital planimeter. It describes the main components of a digital planimeter which include a roller, tracing arm, tracing magnifier, tracing point, and function keys. It then explains the various function keys and their purposes. Finally, it outlines the step-by-step process for measuring the area of a shape using a digital planimeter, which involves selecting a scale, marking a starting point, tracing the outline while holding the tracing point, and reading the area measurement from the display.
The document discusses different types of traverses and methods for conducting traverse surveys. It describes two types of traverses: open traverses that begin and end at points of known and unknown positions, and closed traverses that begin and end at points of known positions, including closed-loop traverses that begin and end at the same point. It also outlines four methods for determining directions during traversing: chain angle method, free needle method, fast needle method, and measuring angles between lines. Finally, it discusses instruments used for measuring angles like compasses and theodolites, and defines different types of bearings including true, magnetic, and arbitrary bearings.
Leveling is a surveying technique used to determine differences in elevation between points. It involves measuring vertical angles and distances to establish spot elevations across an area. There are two main methods - direct and indirect. Direct contouring involves marking points along contour lines in the field, while indirect contouring uses spot elevations from which contours are interpolated on a map. Common techniques include using a level, staff, and plane table or theodolite to obtain elevations and positions of points, which are then contoured. Leveling is important for engineering projects to design facilities and earthworks efficiently based on terrain.
*Introduction
*Controls For Setting Out
*Horizontal control
*Vertical control
*SETTING OUT A BUILDING
*The equipment required for the job
*Method(1):-By using a Circumscribing Rectangle
*Method(2):- By using centre-line-rectangle
* Setting out of culverts
*SETTING OUT A TUNNEL
This document provides information about circular curves used in highways and railways. It discusses the different types of curves including simple, compound, and reverse curves. It defines key elements of circular curves such as radius, deflection angle, tangent length, and mid-ordinate. It presents the relationships between radius and degree of curvature. Finally, it describes various methods for setting out circular curves in the field, including linear methods using offsets and angular methods using a theodolite.
This document provides an overview of hydrographic surveying. It defines key terms like hydrography, soundings, and horizontal and vertical controls. It describes common equipment used for hydrographic surveys like sounding boats, poles, lead lines, sounding machines, and echo sounders. It explains methods for locating soundings, such as using a cross rope, ranges and time intervals, or ranges with angular observations from shore or boat. The goal of hydrographic surveying is to accurately map bodies of water by taking depth measurements and positioning them spatially.
Surveying for Civil engineering is a
particular type of surveying known as "land surveying", it is the
detailed study or inspection, as by gathering information through
observations, measurements in the field, questionnaires, or
research of legal instruments, and data analysis in the support of
planning, designing, and establishing of property boundaries.
Land surveying can include associated services such as mapping
and related data accumulation, construction layout surveys,
precision measurements of length, angle, elevation, area, and
volume, as well as horizontal and vertical control surveys, and
the analysis and utilization of land survey data. Surveyors use
various tools to do their work successfully and accurately, such
as total stations, robotic total stations, GPS receivers, prisms, 3D
scanners, radio communicators, handheld tablets, digital levels,
and surveying software.
Survey data can be directly entered into a GIS from digital
data collection systems on survey instruments. When data is
captured, the user should consider if the data should be captured
with either a relative accuracy or absolute accuracy, since this
could not only influence how information will be interpreted but
also the cost of data captured.
In this paper GIS maps were developed depending on the
field surveying data made for a two traverses. First one has ribs
less than 50m length and the other larger than 50m. Each
traverse is holding five times using five equipments and
instruments: Tape, Level, Digital level, Digital theodolite and
Laser tape. Also those maps were drawn by using both of ACAD
and ArcView softwares. Then a detail surveying map was
produced. The precision was computed for both traverses in each
method. Its value is range from 1/140 to 1/10000.
This document discusses traverse surveys which involve measuring angles and distances between survey points to determine their positions. It provides the objective of traverse surveys which is to find accurate positions of stations to serve as control points for mapping or construction layout. The results section shows the distances, angles, coordinate calculations and adjustments for a sample 4-point traverse with a closure of 0. The discussion explains the traverse calculations and adjustments to distribute errors. The conclusion states that traverse surveys are commonly used for construction site layout and boundary surveys, and errors can be adjusted or the survey repeated.
1. A subsidiary station or satellite station is established near a true or principal station to aid in surveying. Working from whole to part means establishing control points over the entire area with high precision first before determining minor details with less precision to prevent error accumulation.
2. Triangulation uses optical systems or sensors to determine spatial dimensions by measuring angles and distances in spatial triangles. Requirements for selecting a baseline include level ground free of obstructions with intervisible endpoints suitable for network extension.
3. Strength of figure in triangulation depends on triangle angles and considers how errors in measurement affect side length computations, important for layout and precision.
This document provides information about traversing and the tools used for traversing surveys. It discusses the components and types of traverses, including open and closed traverses. It also outlines the apparatus used for traversing, including theodolites, tripods, rods, and plummets. The document provides detailed steps for traverse computation, including determining bearings, latitudes and departures, accuracy checks, adjusting for misclosure, and computing coordinates and areas. Traversing establishes horizontal control networks and is used for boundary surveys, mapping, and construction layout. Precision instruments like total stations and EDM devices have made traversing more accurate.
This document provides information on traversing and the tools used for traversing surveys. It discusses the components of a traverse including bearing, length of lines, latitude and departure. It also outlines the apparatus used for traversing including theodolites, tripods, rods and plummets. The document covers open and closed traverses, types of traverses such as loop and connecting traverses. It provides details on traverse computation steps such as balancing angles, determining bearings, checking for errors and adjusting for misclosures.
TOTAL STATION: THEORY, USES AND APPLICATIONS. Ahmed Nassar
TOTAL STATION: THEORY, USES AND APPLICATIONS.
The total station, (also known as electronic tacheometer) is an instrument that can measure horizontal and vertical angles together with slope distance and can be considered as combined EDM plus electronic theodolite. In common with other electronic surveying equipment, total stations are operated using a multi-function keyboard which is connected to a microprocessor built into the instrument. The microprocessor not only controls both the angle and distance measuring systems but is also used as a small computer that can calculate slope corrections, vertical components, rectangular coordinates and, in some cases, can also store observations directly using an internal memory. Nowadays surveying systems are available which can be use in an integrated manner with Global Positioning System (GPS). so, future total stations may have integrated GPS receivers as part of the measurement unit.
The document discusses triangulation and trilateration methods for horizontal control surveys. It defines triangulation as establishing a network of triangles using measured baselines and calculated angles to determine station positions. Trilateration measures baseline lengths directly using EDM instead of calculating from angles. The document categorizes triangulation into three orders based on accuracy and describes ideal triangle configurations. It also discusses evaluating figure strength to maintain precision and defines well-conditioned triangles that minimize angular error effects.
DUAL BAND GNSS ANTENNA PHASE CENTER CHARACTERIZATION FOR AUTOMOTIVE APPLICATIONSjantjournal
High-accuracy Global Navigation Satellite System (GNSS) positioning is a prospective technology that will be used in future automotive navigation systems. This system will be a composite of the United States' Global Positioning System (GPS), the Russian Federation's Global Orbiting Navigation Satellite System (GLONASS), China Beidou Navigation Satellite System (BDS) and the European Union’s Galileo. The major improvement in accuracy and precision is based on (1) multiband signal transmitting, (2) carrier phase correction, (3) Real Time Kinematic (RTK). Due to the size and high-cost of today’s survey-grade antenna solutions, this kind of technology is difficult to use widely in the automotive sector. In this paper, a low-cost small size dual-band ceramic GNSS patch antenna is presented from design to real sample. A further study of this patch antenna illustrates the absolute phase center variation measured in an indoor range to achieve a received signal phase error correction. In addition, this low-cost antenna solution is investigated when integrated into a standard multi-band automotive antenna product. This product is evaluated both on its own in an indoor range and on a typical vehicle roof at an outdoor range. By using this evaluation file to estimate the receiver position could achieve phase motion error-free result.
DUAL BAND GNSS ANTENNA PHASE CENTER CHARACTERIZATION FOR AUTOMOTIVE APPLICATIONSjantjournal
High-accuracy Global Navigation Satellite System (GNSS) positioning is a prospective technology that will be used in future automotive navigation systems. This system will be a composite of the United States' Global Positioning System (GPS), the Russian Federation's Global Orbiting Navigation Satellite System (GLONASS), China Beidou Navigation Satellite System (BDS) and the European Union’s Galileo. The major improvement in accuracy and precision is based on (1) multiband signal transmitting, (2) carrier phase correction, (3) Real Time Kinematic (RTK). Due to the size and high-cost of today’s survey-grade antenna solutions, this kind of technology is difficult to use widely in the automotive sector. In this paper, a low-cost small size dual-band ceramic GNSS patch antenna is presented from design to real sample. A further study of this patch antenna illustrates the absolute phase center variation measured in an indoor range to achieve a received signal phase error correction. In addition, this low-cost antenna solution is investigated when integrated into a standard multi-band automotive antenna product. This product is evaluated both on its own in an indoor range and on a typical vehicle roof at an outdoor range. By using this evaluation file to estimate the receiver position could achieve phase motion error-free result.
DUAL BAND GNSS ANTENNA PHASE CENTER CHARACTERIZATION FOR AUTOMOTIVE APPLICATIONSjantjournal
High-accuracy Global Navigation Satellite System (GNSS) positioning is a prospective technology that will be used in future automotive navigation systems. This system will be a composite of the United States' Global Positioning System (GPS), the Russian Federation's Global Orbiting Navigation Satellite System (GLONASS), China Beidou Navigation Satellite System (BDS) and the European Union’s Galileo. The major improvement in accuracy and precision is based on (1) multiband signal transmitting, (2) carrier phase correction, (3) Real Time Kinematic (RTK). Due to the size and high-cost of today’s survey-grade antenna solutions, this kind of technology is difficult to use widely in the automotive sector. In this paper, a low-cost small size dual-band ceramic GNSS patch antenna is presented from design to real sample. A further study of this patch antenna illustrates the absolute phase center variation measured in an indoor range to achieve a received signal phase error correction. In addition, this low-cost antenna solution is investigated when integrated into a standard multi-band automotive antenna product. This product is evaluated both on its own in an indoor range and on a typical vehicle roof at an outdoor range. By using this evaluation file to estimate the receiver position could achieve phase motion error-free result.
DUAL BAND GNSS ANTENNA PHASE CENTER CHARACTERIZATION FOR AUTOMOTIVE APPLICATIONSjantjournal
This document discusses the design and evaluation of a dual-band ceramic GNSS patch antenna for automotive applications. It aims to characterize the antenna's phase center variation and offset to achieve carrier phase correction and improve positioning accuracy. The antenna was evaluated on a 250mm ground plane, integrated into a shark-fin antenna on the same ground plane, and mounted on a vehicle roof. The results from indoor and outdoor testing can be used to estimate receiver position with reduced phase error for different vehicle platforms and antenna locations.
DUAL BAND GNSS ANTENNA PHASE CENTER CHARACTERIZATION FOR AUTOMOTIVE APPLICATIONSjantjournal
This document discusses the design and testing of a dual-band ceramic patch antenna for use in automotive GPS applications. It aims to characterize the antenna's phase center variation and offset to enable high-precision positioning. The antenna was tested on a 250mm ground plane, integrated into a shark-fin antenna product, and mounted on a vehicle roof to measure its performance in different scenarios. The results will help estimate receiver position accurately by accounting for phase errors introduced by the antenna geometry.
DUAL BAND GNSS ANTENNA PHASE CENTER CHARACTERIZATION FOR AUTOMOTIVE APPLICATIONSjantjournal
This document discusses the design and testing of a dual-band ceramic patch antenna for use in automotive GPS applications. It aims to characterize the antenna's phase center variation and offset to enable high-precision positioning. The antenna was tested on a 250mm ground plane, integrated into a shark-fin antenna product, and mounted on a vehicle roof to measure its performance in different scenarios. The results will help estimate receiver position accurately by accounting for phase errors introduced by the antenna geometry.
DUAL BAND GNSS ANTENNA PHASE CENTER CHARACTERIZATION FOR AUTOMOTIVE APPLICATIONSjantjournal
High-accuracy Global Navigation Satellite System (GNSS) positioning is a prospective technology that will
be used in future automotive navigation systems. This system will be a composite of the United States'
Global Positioning System (GPS), the Russian Federation's Global Orbiting Navigation Satellite System
(GLONASS), China Beidou Navigation Satellite System (BDS) and the European Union’s Galileo. The
major improvement in accuracy and precision is based on (1) multiband signal transmitting, (2) carrier
phase correction, (3) Real Time Kinematic (RTK). Due to the size and high-cost of today’s survey-grade
antenna solutions, this kind of technology is difficult to use widely in the automotive sector. In this paper, a
low-cost small size dual-band ceramic GNSS patch antenna is presented from design to real sample. A
further study of this patch antenna illustrates the absolute phase center variation measured in an indoor
range to achieve a received signal phase error correction. In addition, this low-cost antenna solution is
investigated when integrated into a standard multi-band automotive antenna product. This product is
evaluated both on its own in an indoor range and on a typical vehicle roof at an outdoor range. By using
this evaluation file to estimate the receiver position could achieve phase motion error-free result.
Case studies of surveys involved in Railway Tunnel constructed under sea.Prudhvi Thota
Case Studies of detailed explanation of Hydro graphic survey, R.T.K. GPS, Seismic designing, profile survey etc involved in the construction and Designing aspects of Mammary Railway Tunnel under the sea.
This document discusses how Global Navigation Satellite Systems (GNSS) receivers and robotic total stations can be combined to provide an automated, accurate, and cost-effective system for monitoring large open-pit mines. Two main options for establishing a consistent reference frame are reviewed: using a network of total stations or combining total stations with GNSS receivers. The advantages of using GNSS receivers to provide absolute control from a stable location away from the mine are discussed. Practical considerations for implementing a combined total station/GNSS system are then presented, including installing the hardware and processing the data to ensure high accuracy.
Iaetsd concepts of surveying with totalstation-a latestIaetsd Iaetsd
This document provides an overview of surveying with a total station, which is a modern surveying instrument that integrates an electronic theodolite, distance measuring instrument, and computer. It discusses the components and functions of a total station, including the gun, batteries, environmental box, data collector, focus adjustment knobs, and data screens. The document also covers electronic distance measurement, basic mapping terms, and advantages of using a total station compared to traditional surveying methods.
RT (Ray Tracing) models are widely used in RAN for channel modelling. Another possible application in
processing chain of base station with multiple purposes: positioning, channel estimation/prediction, radio
resources scheduling and others. In this paper RT positioning technique is addressed for Urban Outdoor
scenario. Proposed robust approach achieves several meters accuracy even in NLOS and multipath
conditions. Developed RT tracking was used for multiuser (MU) precoder prediction and demonstrated
significant capacity gain. Also, this paper discloses practical aspects for achieving high accuracy.
This document summarizes a paper that proposes using ray tracing for 5G positioning, channel estimation, and multi-user precoding. It describes using ray tracing to estimate the angles of arrival of uplink signals from user equipment at distributed base stations. The estimated angles are then used in a joint positioning technique run in the cloud to determine the user's location. Simulation results show meter-level accuracy can be achieved even in non-line-of-sight conditions. Ray tracing tracking is also used for channel prediction and improves spectral efficiency. Practical considerations for achieving high positioning accuracy with this approach are also discussed.
Determining location information of sensor node is an essential issue to capture the sensed data and to
update the necessary information in many wireless sensor network applications, such as healthcare services,
military applications, warning systems, environmental monitoring etc. Mobile Anchor Node is used to achieve
Localization in a wireless sensor networks. Hence the main challenge is to design and develop a Path Planning
Algorithm for a Mobile Anchor Node to broadcast three consecutive non-collinear messages for location
estimation which in turn increases localization accuracy and coverage and also reduces time required to
determine location information. In this paper, I propose a Path Planning Algorithm called Z-curve to perform
trilateration calculation to estimate sensor nodes location. Proposed trajectory can successfully localize all
deployed sensor nodes in a network region of interest with more accuracy and consumes less time for
localization. Furthermore, to handle obstacles, Z-curve obstacle-handling trajectory is proposed.
Keywords— Wireless sensor networks, mobile anchor node, path planning, non-collinear, localization
speaker design with Enterprise Dynamics (ED) softwareMarvin Ken
The document discusses the simulation of a loudspeaker production line to evaluate efficiency and meet production targets. It involves modeling the assembly process with various steps like component sorting, assembly of parts, installation of electronics, and quality testing. Both automated and manual methods are used. The simulation found that 8 stations were needed to meet cycle times. Adjusting cycle times and balancing workstations improved output. Implementing lean manufacturing principles like reducing waste and continuous improvement could further enhance productivity and efficiency.
This document discusses soil compaction, including the process of compacting soil to increase density, theories of compaction involving compaction curves and factors that influence them, laboratory compaction tests, and field compaction methods and control. The key points are that compaction increases soil density by packing particles more closely together, compaction curves show the relationship between dry density, moisture content, and compactive effort, and both laboratory and field tests are used to evaluate compaction of soil.
This document discusses soil description and classification. It provides an introduction and overview of soil description, which involves details of material and mass characteristics. Soil classification involves allocating soils to groups based on material characteristics like particle size and plasticity. The document then describes the British and Unified soil classification systems, including their differences. It provides examples of soil classifications and describes the plasticity chart. It also notes some shortcomings of classification systems in not considering in situ soil properties.
7 applications in geotechnical engineeringMarvin Ken
Soil is one of the oldest and most complex construction materials due to variations in soil types. Karl Terzaghi studied soil mechanics in the early 20th century and established it as a discipline of civil engineering. The document defines key terms related to soil properties including porosity, saturation, void ratio, unit weights, and water content. It also discusses traditional areas of geotechnical engineering like site investigation, compaction, consolidation, and foundations. Site investigation involves characterizing subsurface conditions through borings, sampling, and laboratory testing.
The document discusses particle size distribution analysis of soils through sieve analysis and sedimentation analysis. Sieve analysis involves separating soil particles by size using a stack of sieves and determining the percentage of particles in each size fraction. Sedimentation analysis uses Stokes' law to determine the distribution of silt and clay sizes. Together, these tests provide full particle size distribution data used for soil classification and determining suitability for engineering applications. The document outlines the procedures, equipment, and interpretation of results from sieve analysis testing.
This document describes various laboratory methods for determining soil properties, including liquid limit, plastic limit, and field density. The liquid limit can be found using a Casagrande apparatus or cone penetrometer, which measure the number of blows or penetration depth required for a soil sample to close a groove at different water contents. The plastic limit is the water content at which a soil thread crumbles. Field density is measured using a core cutter method or sand replacement method.
The document discusses the consistency and plasticity of soils. It defines four states of consistency - liquid, plastic, semisolid, and solid - based on the soil's water content. The boundaries between these states are known as consistency limits, including the liquid limit (LL), plastic limit (PL), and shrinkage limit (SL). The liquid limit is the minimum water content at which a soil acts like a liquid, the plastic limit is the minimum content for the soil to be deformed without cracking, and the shrinkage limit is the maximum content before the soil volume decreases with water loss. Laboratory tests are used to determine each limit.
This document defines key terms and relationships used in geotechnical engineering to describe the phase properties of soils. Soils are composed of solids, water, and air. Relationships defined include void ratio, moisture content, porosity, degree of saturation, density, bulk density, saturated density, and dry density. Diagrams are presented showing typical phase relationships of soil masses and the volumetric proportions of solids, water, and air that make up different soil conditions. Commonly used equations relating these phase properties are also provided.
This document discusses soil mineralogy and the structure of clay minerals. It begins by defining minerals, crystals, and the atomic structure of soil particles. The primary types of bonds in minerals are then explained, including ionic, covalent, hydrogen, and Van der Waals bonds. The basic structural units of clay minerals are silica and aluminium/magnesium sheets, which combine to form different clay types like kaolinite, montmorillonite, and illite. Soil structure is also covered, describing single-grained, honeycomb, flocculated, and matrix structures found in soils.
Soil formation is a long process where rocks and minerals are broken down through weathering. Weathering can be physical, through direct contact with heat, water, ice and pressure, or chemical, where the composition of rocks changes through decomposition. This forms residual soils that remain in place or alluvial soils transported by water. Physical weathering produces cohesionless soils like sand and gravel, while chemical weathering forms clay and other compounds.
This document defines soil mechanics and geotechnical engineering. Soil mechanics is the study of soil behavior, providing the theoretical basis for geotechnical engineering. Geotechnical engineering uses soil mechanics, rock mechanics, and engineering geology principles to investigate subsurface conditions, evaluate stability of natural slopes and structures, assess risks from site conditions, and design earthworks and foundations. A typical geotechnical engineering project involves site investigation, determination of material properties, and design of foundations and earthworks for intended structures.
This document provides an overview and outline for an introductory geotechnical engineering course. It includes:
- A description of topics covered such as soil formation, properties, classification, compaction, and permeability.
- Learning outcomes like understanding soil engineering properties, identification of soil engineering problems, and basic analytical procedures.
- Teaching methods including lectures, examples, student discussions, and textbook readings.
- An outline of course lessons covering soil formation, properties, compaction, classification, and laboratory tests.
- Assessment breakdown of lectures, labs, exams.
This document outlines laboratory experiments for a geotechnical engineering course, including determining liquid limit, plastic limit, dry density, particle size distribution, compaction, and specific gravity of soil. It describes how geotechnical investigations are performed through surface and subsurface exploration to obtain soil properties for engineering design, and notes tests will be conducted in groups and laboratory experiment reports should follow a specific format.
This document provides a course description for FCE 311 - Geotechnical Engineering I, a 3rd year undergraduate course offered by the University of Nairobi's Department of Civil and Construction Engineering. The course is an introduction to soil mechanics, focusing on soil formation, structure, physical properties, classification, compaction, and permeability. Through lectures, examples, discussions, and assigned reading, students will develop an understanding of soil engineering properties and how to apply basic analytical procedures and laboratory testing methods to solve engineering problems involving soil. Assessment will include laboratory tests, continuous assessment tests, and a final exam.
Data Communication and Computer Networks Management System Project Report.pdfKamal Acharya
Networking is a telecommunications network that allows computers to exchange data. In
computer networks, networked computing devices pass data to each other along data
connections. Data is transferred in the form of packets. The connections between nodes are
established using either cable media or wireless media.
Sachpazis_Consolidation Settlement Calculation Program-The Python Code and th...Dr.Costas Sachpazis
Consolidation Settlement Calculation Program-The Python Code
By Professor Dr. Costas Sachpazis, Civil Engineer & Geologist
This program calculates the consolidation settlement for a foundation based on soil layer properties and foundation data. It allows users to input multiple soil layers and foundation characteristics to determine the total settlement.
This study Examines the Effectiveness of Talent Procurement through the Imple...DharmaBanothu
In the world with high technology and fast
forward mindset recruiters are walking/showing interest
towards E-Recruitment. Present most of the HRs of
many companies are choosing E-Recruitment as the best
choice for recruitment. E-Recruitment is being done
through many online platforms like Linkedin, Naukri,
Instagram , Facebook etc. Now with high technology E-
Recruitment has gone through next level by using
Artificial Intelligence too.
Key Words : Talent Management, Talent Acquisition , E-
Recruitment , Artificial Intelligence Introduction
Effectiveness of Talent Acquisition through E-
Recruitment in this topic we will discuss about 4important
and interlinked topics which are
Better Builder Magazine brings together premium product manufactures and leading builders to create better differentiated homes and buildings that use less energy, save water and reduce our impact on the environment. The magazine is published four times a year.
This is an overview of my current metallic design and engineering knowledge base built up over my professional career and two MSc degrees : - MSc in Advanced Manufacturing Technology University of Portsmouth graduated 1st May 1998, and MSc in Aircraft Engineering Cranfield University graduated 8th June 2007.
1. Prof. Dr.-Ing. John Bosco Kyalo Kiema
University of Nairobi
Email: jbkkiema@uonbi.ac.ke
by
Engineering Surveying
II
2. Course Outline
Introduction. Horizontal Control; traverse
observation, calculation and adjustment. Vertical
control: Levelling and contouring. Applications in
highway drainage and setting out works. Area and
volumes. Mass haul diagram. Practicals: field
surveying.
4. References
1. Awange, J.L., and Kiema, J.B.K. (2013). Environmental
Geoinformatics: Monitoring and Management. Springer Verlag.
2. Bannister, A., Raymond, S., and Baker, R. (1998). Surveying. Pitmans
ELBS. 7th Ed.
3. Irvine and Macclennan (2006). Surveying for Construction. McGraw, C.
5th Ed.,
4. Schofield, W. and Breach, M. (2007). Engineering Surveying.
Butterworth-Heinemann, UK. 6th Ed.
5. Uren and Price. (2010). Surveying for Engineers. Macmillan Press Ltd.
5th Ed.
6. Wolf, P, R., and Ghilani, C.D., (2006). Elementary Surveying: An
Introduction to Geomatics. Pearson Prentice Hall. New Jersey. 11 Ed.
5. Course Assignment/Term Paper
Using suitable examples discuss the role of
Geoinformatics in the monitoring and management of
environmental pollution.
6. Lecture Outline
Part 2: Traversing
Overview of Control Surveys
Concept of Traversing
Traverse Computation
Accuracy of Traversing
Part 1: Background
Basic Principle of Surveying
Datum Concept
Tenets of Survey Practice
Part 3: Vertical Control
Introduction and Definitions
Principle of Levelling
Sources of Errors
Applications of Levelling
Part 4: Earthworks
Computation of Areas and Volumes
Mass Haul Diagrams
7. Part 1: Background
Basic Principle of Surveying
Datum Concept
Tenets of Survey Practice
8. Basic Principle of Surveying
1) Working from the “whole to the part”. First
provide control using methods with higher
accuracy followed by detail mapping using
lower accuracy and cheaper methods.
2) Always perform independent checks. Make
more observations than the basic minimum
needed.
3) Specifications and accuracy required.
9. Datum Concept
Basic problem in Surveying is to determine the position
(measure) of features on Earth’s curved surface and
map (coordinate) them for diverse purposes often onto
a plane.
Datum refers to a plane or surface to which positions
and elevations of points are referenced.
Ellipsoid is reference surface in geodetic surveys.
Best fitting ellipsoid is selected.
For heighting the most commonly adopted datum is
the Mean Sea Level. This is taken with data from
coastal tide gauges over several years.
11. Tenets of Survey Practice
Complete in shortest possible time.
Complete at the least possible cost.
Complete according to client instruction(s) and
survey manual specifications.
Complete using instrumentation of appropriate
accuracy.
12. Part 2: Traversing
Horizontal Control Surveys
Concept of Traversing
Traverse Computation
Accuracy of Traversing
13. In line with the Principle of Surveying a control
survey provides a framework of survey points,
whose relative positions are known to
prescribed degrees of accuracy.
The areas covered by these points may extend
over a whole country and form the basis for the
national maps of that country.
Alternatively the area may be relatively small,
encompassing a construction site for which a
large-scale plan is required. Although the areas
covered in construction are usually quite small,
the accuracy may be required to a very high
order.
Horizontal Control Surveys
14. Horizontal Control Surveys (2)
Hence control networks provide a reference
framework of points for:
(1) Topographic mapping and large-scale plan
production.
(2) Dimensional control of construction work.
(3) Deformation surveys for all manner of structures,
both new and old.
(4) The extension and densification of existing control
networks.
15. Horizontal Control Surveys (3)
Techniques used in the provision of horizontal control
surveys include:
(1) Traversing
(2) Triangulation Classical methods
(3) Trilateration
(4) Triangulateration Modern approaches
(5) Satellite position fixing (Global Navigation Satellite
Systems)
(6) Inertial position fixing
(7) Continuously Operating Reference Stations (CORS).
Whilst the above systems establish a network of
points, single points may be fixed by intersection
and/or resection.
16. Since the advent of EDM equipment, traversing
has emerged as the most popular method of
establishing control networks not only in
engineering surveying but also in geodetic work.
Traverse networks are, to a large extent, free
of the limitations imposed on the other systems
and have the following advantages:
(1) Much less reconnaissance and organization
required in establishing a single line of easily
accessible stations compared with the laying out
of well-conditioned geometric figures.
(2) The limitations imposed on the other systems by
topographic conditions do not apply to
traversing.
Concept of Traversing
17. Concept of Traversing (2)
(3) The extent of observations to only two stations
at a time is relatively small and flexible
compared with the extensive angular and/or
linear observations at stations in the other
systems. It is thus much easier to organize.
(4) Traverse networks are free of the strength of
figure considerations so characteristic of
triangular systems. Thus once again the
organizational requirements are reduced.
(5) Scale error does not accrue as in triangulation,
whilst the use of longer sides, easily measured
with EDM equipment, reduces azimuth swing
errors.
18. (6) Traverse stations can usually be chosen so as to
be easily accessible, as well as convenient for
the subsequent densification of lower order
control.
(7) Traversing permits the control to closely follow
the route of a highway, pipeline or tunnel, etc.,
with the minimum number of stations.
From the logistical point of view, traversing is
far superior to the other classical horizontal
control methods and offers at least equivalent
accuracy.
Concept of Traversing (3)
19. Definition of Traversing
Traversing is a surveying technique used to
determine the planimetric positions (Easting and
Northing: EB and NB below) of control points or
setting out points using measured angles and
distances (DAB and Q below).
EB=EA+ΔEAB= EA+ DABsin Q
NB=NA+ΔNAB= NA+ DABcosQ
20. In traversing, the relative position of control
points is fixed by measuring the horizontal angle
at each point, subtended by the adjacent
stations, and the horizontal distance between
consecutive pairs of stations.
The liability of a traverse to undetected error
makes it essential that there should be some
external check on its accuracy. Hence, the
traverse needs to commence from and connect
into known points of greater accuracy than the
traverse.
Types of Traverses
21. Types of Traverses (2)
In this way, the error vector of misclosure can
be quantified and distributed throughout the
network, to produce geometric correctness. Such
a traverse is called a ‘link’ traverse.
The link traverse has certain advantages over
the remaining types, in that systematic error in
distance measurement and orientation are clearly
revealed by the error vector.
Alternatively, the error vector can be obtained
by completing the traverse back to its starting
origin. Such a traverse is called a ‘polygonal’ or
‘loop’ traverse.
22. Types of Traverses (3)
a) Link traverse b) Loop traverse (oriented)
d) Open (free) traverse
c) Loop traverse (independent)
23. Both the ‘link’ and ‘polygonal’ traverses are
generally referred to as ‘closed’ traverses.
The third type of traverse is the ‘free’ or
‘open’ traverse, which does not close back onto
any known point and which therefore has no way
of detecting or quantifying the errors.
Open traverses are not recommended due to
the lack of checks. Nevertheless, it is
frequently utilized in mining and tunnelling work
because of the physical restriction on closure.
Types of Traverses (4)
24. Field Procedure
Reconnaissance is a vitally important part of any
survey project. Its purpose here is to decide
the best location for the traverse points.
In the first instance the points should be
intervisible from the point of view of traverse
observations.
If the purpose of the control network is the
location of topographic detail only, then they
should be positioned to afford the best view of
the terrain, thereby ensuring that the maximum
amount of detail can be surveyed from each
point.
25. Field Procedure (2)
If the traverse is to be used for setting out
e.g., the centre-line of a road, then the
stations should be sited to afford the best
positions for setting out the intersection points
(IPs) and tangent points (TPs), to provide
accurate location.
The distance between stations should be kept as
long as possible to minimize effect of centring
errors.
Finally, as cost is always important, the scheme
should be one that can be completed in the
minimum of time, with the minimum of
personnel.
26. Sources of Errors
The sources of error in traversing include:
(1) Errors in the observation of horizontal and vertical
angles (angular error).
(2) Errors in the measurement of distance (linear
error).
(3) Errors in the accurate centring of the instrument
and targets, directly over the survey point
(centring error).
27. Traverse Computation
Using the data given below, compute the
coordinates of various points in the following
traverse.
Apply Bowditch rule to distribute the
misclosure.
28. Station Observations Station Observations
At Tr29 At Tr37
Tr28 97 11 10 Tr36 179 02 59
Tr10 279 15 11 Tr42 2154 58
Tr36 52 15 03
At Tr42
At Tr36 Tr37 201 54 58
Tr29 232 15 03 Tr43 234 55 58
Tr37 359 02 59 Tr41 120 32 05
Traverse Computation (2)
32. ΔN (m) ΔE
By Datum: 174.440 84.430
By Traverse: 174.456 84.442
Misclosure: -0.016 -0.012
Length of Traverse = 209.567m
Accuracy = Sqrt{(-0.016)2+(-0.012)2}/209.567 = 1 in 13,000
(approx)
Computation of Coordinates (2)
33. Accuracy of Traversing
Traversing is generally more accurate than
classical triangulation and trilateration.
Due to the weak geometry of a traverse, it
generally has only three degrees of freedom (that
is three redundant observations), it is difficult to
arrive at an estimate of accuracy.
Although there have been many attempts to
produce equations defining the accuracy of a
traverse, at the present time the best approach is
a strength analysis using variance–covariance
matrices from a least squares adjustment.
34. Blunders in the observed data
Blunders or mistakes in the measurement of the
angles, results in gross angular misclosure.
Provided it is only a single blunder it can easily be
located.
In the case of an angle, the traverse can be computed
forward from X (Figure) and then backwards from Y.
The point which has the same co-ordinates in each
case, is where the blunder occurred and the angle must
be re-observed.
Figure: Detection of
angular traverse blunder
35. Blunders in the observed data (2)
In the case of a blunder in measuring distance,
the incorrect leg is the one whose bearing is
similar to the bearing of the error vector.
If there are several legs with similar bearings the
method fails.
Again the incorrect leg must be re-measured.
36. Part 3: Vertical Control
Introduction and Definitions
Principle of Levelling
Sources of Errors
Applications of Levelling
37. The process of determining elevations (heights)
of points of interest above or below a reference
datum or differences in elevations.
For most practical applications only the
difference in elevation between points of
interest and not absolute heights is often
required.
Used in all aspects of surveying, particularly for
engineering surveys, route surveys, construction,
etc.
Different methods may be used for estimating
heights or height differences including;
differential levelling, barometric heighting,
trigonometric heighting, gravimetry and
satellite positioning etc.
Overview of Levelling
38. a) Differential levelling: basic idea involves obtaining of height
difference between points by measuring their vertical distance
from a horizontal line of sight.
b) Trigonometric heighting: method is generally used in
determination of elevation differences of lower accuracy than
spirit levelling. It is useful where it is very difficult (or
impossible) for differential levelling to be undertaken (e.g.
towers, spires, mountain ranges etc).
c) Barometric heighting: method consists of reading air pressure
differences from which elevation differences are computed.
d) Gravimetry: by measuring the gravitational potential variation
between different points it is possible to correlate this to
differences in heights.
d) Satellite Positioning: method is poised for extensive use in the
future with its only drawback being the determination of the
separation between the geoid and ellipsoid in areas of interest.
Comparison of Various Heighting Methods
41. A horizontal line is a line that
is tangential to the level line
at a particular point. Hence a
horizontal line is perpendicular
to the direction of gravity.
Levelling Line and Horizontal Line
A level line is a line that is
normal to the direction of
gravity as shown by a plumbline
at any point. A level line is
curved by virtue of the shape
of the Earth. Hence, a level
line is a line in which all points
are the same height.
43. Datum: A level surface to which elevations of points may
be referenced. The most commonly adopted datum is the
Mean Sea Level (MSL).
Reduced level: The elevation (above or below) of a point
in relation to the Datum.
Benchmark (BM): A permanent monument or feature for
which elevation is known. BMs are built on stable rock.
Three (3) types of benchmarks can be distinguished:
1) Fundamental benchmarks (FBMs): Very stable concrete structures
most often built into rock forming part of the primary levelling
network.
2) Ordinary benchmarks: Concrete points or marks on rocks, culverts,
bridges etc constructed between FBMs.
3) Temporary benchmarks (TBMs): Stable points established in the course
of a survey between established benchmarks, which may be some
distance away.
Datums, Reduced Levels and Benchmarks
44. A (curved) surface orthogonal to the plumb line
everywhere.
More correctly an equipotential surface for which
gravitational potential is constant.
A still body of water unaffected by tides is a good
analogy.
They are not equidistant apart, but converge and diverge
due to changes in density.
Level Surface
45. Vertical Line
The direction of gravity
Therefore the direction indicated by a plumb
line
In general it deviates from a line emanating
from the geometric centre of the Earth
In reality it is curved, but this can be
neglected in small plane surveys
46. Horizontal Plane
A plane tangent to a level surface (orthogonal
to the plumb line).
The collimation axis (line of sight) of a levelling
instrument that is in correct adjustment, once
levelled, defines a horizontal plane as the
instrument is rotated.
49. Level and reading of staff
Staffs of a variety of lengths and
graduation styles made from a
variety of materials (wood,
aluminium, fibreglass) exist.
The alternate metre lengths are in
black and red on a white
background.
Majority of staffs are telescopic
or socketed in three sections for
easy carrying.
Graduations can take various forms
with E-pattern type popular. The
smallest graduation on the staff is
0.01 m, with readings estimated to
the nearest millimetre.
As the staff must be held vertical
during observation it should be
fitted with a circular bubble.
53. Two Peg Test
This test is often conducted before using a level for any
levelling exercise.
The purpose of the test is find out to if the line of
collimation is parallel to the bubbles tube axis.
Collimation error occurs if the line of sight is not truly
horizontal when the bubble is centred. The line of sight
may be inclined either upwards or downwards from
the horizontal.
54. Levelling Procedure
A horizontal line of sight is established using some
form of levelling mechanism:
Spirit level tube
Swinging pendulum
A graduated staff is read through the telescope of
the level.
The elevation of points can be established by first
reading the staff on a bench mark.
The staff is then moved to the desired point, the
level is turned and the staff is read again.
55. Levelling Procedure (2)
The reading at the benchmark is called the backsight
(BS)
The reading taken after turning the instrument and
moving the staff is the foresight (FS)
56. Levelling Procedure (3)
To continue levelling, the staff is kept on the point at
A and the instrument moved to the midpoint between
A and the next point, B.
A is called the change point (CP) or turning point (TP).
The staff at A is carefully turned toward the
instrument and a BS reading taken.
Then the staff is moved to B and a FS reading is
made.
The procedure is repeated as many times as needed.
The levelling should always end on a BM as a check!
57. Levelling Procedure (4)
Two note reduction methods for calculating elevations
from the BS and FS observations exist.
Each use only two equations for the computations.
Height of Collimation method HC = Elev + BS
Elev = HC – FS
Rise and Fall method Rise (or Fall) = BS – FS
Elev = Previous Elev + Rise (or Fall)
A Fall is simply a negative Rise
60. Accuracy in Levelling
Many factors affect accuracy of ordinary levelling:
Reading of staff.
Bubble not being central.
Instrument (level) being out of adjustment. Ensuring
that backsights and foresights are equal in length
lessens effects of maladjustment.
Differential settlement of the tripod.
Tilting and settlement of the staff.
Sensitivity of the bubble or compensator.
61. Acceptable Misclosures
Maximum acceptable misclosure depends on class of
levelling and specifications for the particular survey.
As a guideline the following figures give an indication of
misclosures for various classes:
Precise levelling: 4K
2nd order levelling: 8K
3rd order levelling: 12K.
Ordinary levelling falls into this category. On rough
ground, allowance may be made for misclosures of up to
30K (Where K is the total distance levelled in
kilometres).
62. Precise Levelling
This class of levelling requires further refinement to
field technique and instrumentation to that applied in
ordinary levelling.
The accuracy requirements for this class of levelling
are more stringent than for ordinary levelling.
Typical rules governing field technique for precise
levelling include:
1) Backsights and foresights are made equal in length,
two staffs being used.
2) Readings are made to one particular staff at each
setup, and there being an even number of set ups.
Readings are made to all three hairs of the reticule
at each set up and a special format for booking of
readings used.
63. Precise Levelling (2)
3) All lines of levels to be run twice in opposite
directions, the runs being made on different days
with different change points.
4) All change points made on special footplates.
5) Staff readings below 0.5m level to be avoided.
6) Special staffs with invar strip and a bubble to be
used.
7) Only levels designed for precise levelling (or
comparable accuracy) should be used (e.g. with
parallel plate micrometer).
8) If the standards in the regulations for allowable
error are not complied with, the work is repeated.
64. Sources of Errors
Equipment errors
(a) Collimation error
(b) Compensator not working
(c) Parallax
(d) Defective staff
(e) Defective Tripod
65. Sources of Errors (2)
Field or on-sight errors (Gross error sources)
(a) Staff reading error.
(b) Unstable change point.
(c) Non‐vertical staff.
(d) Booking error
(e) Instrument not level
(f) Handling the instrument and tripod
Effect of curvature and refraction
(a) Earth curvature.
(b) Vertical collimation error in the instrument.
(c) Temperature relation expansion in the staff.
66. How to Reduce Errors
Levelling should start and finish at known Bench Mark.
Where possible, all sight lengths should be below 50m.
The staff must be held vertically.
BS and FS must be kept equal for each instrument
position.
Rise and Fall method should be used when heighting
controls.
HCM should be used when setting out.
For Automatic levels, staff readings should be booked
immediately they are observed.
67. Establishing vertical control.
To establish heights of points during
constructions – setting out levels.
For contouring purposes.
For road cross‐section, longitudinal
sections/profiles or volumes of
Earthwork in civil engineering works.
For provision of levels of inclined surface
during construction.
Applications of levelling
68. Part 4: Earthworks
Overview
Computation of Areas and Volumes
Mass Haul Diagrams
69. Estimation of areas and volumes is basic to
most engineering schemes such as route
alignment, reservoirs, tunnels, etc.
Excavation and hauling of material is the
most significant and costly aspect of the
work, on which profit or loss may depend.
Areas may be required in connection with
the purchase or sale of land, with the
subdivision of land or with the grading of
land.
Overview
70. Earthwork volumes are estimated to:
i) enable route alignment to be located at such
lines and levels that cut and fill are balanced
as far as practicable;
ii) to enable contract estimates of time and
cost to be made for proposed work;
iii) to form the basis of payment for work
carried out.
Overview (2)
72. Many volumes encountered in civil engineering appear, at
first glance, to be rather complex in shape.
Generally, estimation of volumes can be divided into
computation of volumes for prisms, wedges or pyramids.
(1) Prism
The two ends of the prism (Figure 9.17) are equal and
parallel, the resulting sides thus being parallelograms.
Volume = AL
Volumes
(2) Wedge
Volume of wedge (Figure 9.18)
= L/6 (sum of parallel edges × vertical height of base)
= L/6 [(a + b + c) × h] (9.7a)
when a = b = c: V = AL/2
73. Mass-haul diagrams (MHD) are used to compare
the economy of various methods of earthwork
distribution on road or railway construction
schemes.
By the combined use of the MHD plotted directly
below the longitudinal section of the survey centre-
line, one can find:
(1) The distances over which cut and fill will balance.
(2) Quantities of materials to be moved and the
direction of movement.
(3) Areas where earth may have to be borrowed or
wasted and the amounts involved.
(4) The best policy to adopt to obtain the most
economic use of plant.
Mass-Haul Diagrams