This document provides information on two soil classification systems: the AASHTO and USCS systems. The AASHTO system classifies soils into eight groups (A-1 through A-8) based on particle size distribution, liquid limit, and plasticity index. The USCS system classifies soils into four categories (coarse-grained, fine-grained, organic, and peat) based on grain size, plasticity, and compressibility. Both systems use laboratory tests like sieve analysis and Atterberg limits to determine the soil classification group. The document describes the classification criteria and symbols used in detail for each system.
Class notes of Geotechnical Engineering course I used to teach at UET Lahore. Feel free to download the slide show.
Anyone looking to modify these files and use them for their own teaching purposes can contact me directly to get hold of editable version.
Class notes of Geotechnical Engineering course I used to teach at UET Lahore. Feel free to download the slide show.
Anyone looking to modify these files and use them for their own teaching purposes can contact me directly to get hold of editable version.
This document discusses soil classification systems. It describes the purpose of classifying soils and two commonly used systems: the Unified Soil Classification System (USCS) and the American Association of State Highway and Transportation Officials System (AASHTO). The USCS divides soils into major groups based on grain size and plasticity characteristics. The AASHTO system focuses on classifying soils for road construction using groups determined by liquid limit, plasticity index, and grain size distribution. Procedures and examples are provided for classifying soils in both systems.
This lecture discusses the bearing capacity of foundations. It introduces Terzaghi's bearing capacity theory, which evaluates the ultimate bearing capacity of shallow foundations based on a failure surface geometry. Terzaghi's equation for ultimate bearing capacity is presented. Meyerhof's and Hansen's theories are also introduced, which improved on Terzaghi's theory. Hansen's theory provides a more general bearing capacity equation that can be applied to both shallow and deep foundations. Safety factors are applied to the ultimate bearing capacity to determine allowable bearing capacity for foundation design. Settlement criteria may also control and limit the allowable bearing capacity in some cases.
This document discusses consolidation settlement, which occurs when saturated soil is loaded and squeezed, causing water to be expelled over time (years depending on soil permeability) and the soil volume to decrease. As water flows out, the soil settles vertically in direct proportion to the volume decrease. Two methods estimate consolidation settlement: using the coefficient of volume compressibility (mv) or the void ratio-effective stress (e-logσ'v) relationship. Practical applications include using prefabricated vertical drains to accelerate consolidation in clay soils.
This document provides information about soil compaction from an engineering lecture. It defines soil compaction, discusses how it increases soil strength and reduces permeability. It explains the principles of compaction including how it works by reducing air voids. A soil compaction curve is presented, defining optimum moisture content. Factors that affect compaction are listed such as soil type, compactive effort, and water content. Common compaction methods are also briefly outlined.
This presentation covers the topic of particle size classification, dry sieve analysis, wet sieve analysis, sedimentation analysis, stokes law, methods of sedimentation analysis, Indian Standard Soil classification system.
This document discusses the consolidation of soil. It defines important terms like compression, compressibility, and consolidation. It outlines the differences between compaction and consolidation. The importance of consolidation theory is that it provides information on total settlement, time for settlement, and types of settlement. Terzaghi's spring analogy is described to explain the consolidation process. A one-dimensional consolidation test procedure is outlined. Important definitions related to consolidation like compression index, swelling index, and coefficients are provided. The document also discusses normally, under, and over consolidated soils and how to determine preconsolidation pressure. Terzaghi's one-dimensional consolidation theory and solution are presented. Methods to determine degree of consolidation and coefficient of consolidation from laboratory test data are
Class notes of Geotechnical Engineering course I used to teach at UET Lahore. Feel free to download the slide show.
Anyone looking to modify these files and use them for their own teaching purposes can contact me directly to get hold of editable version.
Class notes of Geotechnical Engineering course I used to teach at UET Lahore. Feel free to download the slide show.
Anyone looking to modify these files and use them for their own teaching purposes can contact me directly to get hold of editable version.
This document discusses soil classification systems. It describes the purpose of classifying soils and two commonly used systems: the Unified Soil Classification System (USCS) and the American Association of State Highway and Transportation Officials System (AASHTO). The USCS divides soils into major groups based on grain size and plasticity characteristics. The AASHTO system focuses on classifying soils for road construction using groups determined by liquid limit, plasticity index, and grain size distribution. Procedures and examples are provided for classifying soils in both systems.
This lecture discusses the bearing capacity of foundations. It introduces Terzaghi's bearing capacity theory, which evaluates the ultimate bearing capacity of shallow foundations based on a failure surface geometry. Terzaghi's equation for ultimate bearing capacity is presented. Meyerhof's and Hansen's theories are also introduced, which improved on Terzaghi's theory. Hansen's theory provides a more general bearing capacity equation that can be applied to both shallow and deep foundations. Safety factors are applied to the ultimate bearing capacity to determine allowable bearing capacity for foundation design. Settlement criteria may also control and limit the allowable bearing capacity in some cases.
This document discusses consolidation settlement, which occurs when saturated soil is loaded and squeezed, causing water to be expelled over time (years depending on soil permeability) and the soil volume to decrease. As water flows out, the soil settles vertically in direct proportion to the volume decrease. Two methods estimate consolidation settlement: using the coefficient of volume compressibility (mv) or the void ratio-effective stress (e-logσ'v) relationship. Practical applications include using prefabricated vertical drains to accelerate consolidation in clay soils.
This document provides information about soil compaction from an engineering lecture. It defines soil compaction, discusses how it increases soil strength and reduces permeability. It explains the principles of compaction including how it works by reducing air voids. A soil compaction curve is presented, defining optimum moisture content. Factors that affect compaction are listed such as soil type, compactive effort, and water content. Common compaction methods are also briefly outlined.
This presentation covers the topic of particle size classification, dry sieve analysis, wet sieve analysis, sedimentation analysis, stokes law, methods of sedimentation analysis, Indian Standard Soil classification system.
This document discusses the consolidation of soil. It defines important terms like compression, compressibility, and consolidation. It outlines the differences between compaction and consolidation. The importance of consolidation theory is that it provides information on total settlement, time for settlement, and types of settlement. Terzaghi's spring analogy is described to explain the consolidation process. A one-dimensional consolidation test procedure is outlined. Important definitions related to consolidation like compression index, swelling index, and coefficients are provided. The document also discusses normally, under, and over consolidated soils and how to determine preconsolidation pressure. Terzaghi's one-dimensional consolidation theory and solution are presented. Methods to determine degree of consolidation and coefficient of consolidation from laboratory test data are
Class notes of Geotechnical Engineering course I used to teach at UET Lahore. Feel free to download the slide show.
Anyone looking to modify these files and use them for their own teaching purposes can contact me directly to get hold of editable version.
Geophysical methods of soil/Foundation testing Pirpasha Ujede
Geophysical methods such as seismic refraction and resistivity testing provide non-invasive subsurface investigation over large areas more quickly and cheaply than traditional boring and testing. However, geophysical results require interpretation and are less definitive. Both methods are important, with geophysical testing used for initial screening and borings to accurately determine soil properties. Seismic refraction uses shock waves to determine layer velocities and depths, while resistivity measures subsurface resistivity variations related to moisture, compaction, and material to infer stratigraphy.
Class notes of Geotechnical Engineering course I used to teach at UET Lahore. Feel free to download the slide show.
Anyone looking to modify these files and use them for their own teaching purposes can contact me directly to get hold of editable version.
Design of flexible pavements as per IRC37 SupriyaPal10
Flexible pavements work by distributing wheel loads across layers to reduce stress. The document discusses flexible pavement design according to Indian Road Congress guidelines for design traffic up to 150 million standard axles. It describes evaluating subgrade strength, calculating design traffic loads, and using CBR and thickness design charts to determine the appropriate flexible pavement layers and thicknesses based on subgrade strength and traffic volume.
This document provides an overview of the Unified Soil Classification System (USCS), including its development, major categories of soils, naming conventions, definitions of grain sizes, procedures for classifying organic soils, and terminology. The USCS is the preferred soil classification system for geotechnical engineers. It categorizes soils based on grain size distribution and plasticity characteristics of the fine fraction. Soils are classified as coarse-grained, fine-grained, or organic, and further designated by specific letters and graphic symbols according to their composition.
The document discusses three soil tests: the liquid limit test determines the moisture content needed for a soil pat to close a groove after 25 drops from 10 mm; the plastic limit test finds the moisture content where a 3 mm soil thread will crumble; and the shrinkage limit test measures the volume and mass of wet and dried soil in a dish to determine moisture loss.
Vibration method for ground improvement techniqueABHISHEK THAKKAE
This document discusses various ground improvement techniques, including vertical drains, soil nailing, stone columns, vibro compaction, and dynamic compaction. Vertical drains accelerate consolidation by facilitating drainage of pore water through columns of pervious material placed in soil. Soil nailing uses steel tendons drilled and grouted into soil to create a reinforced composite mass. Stone columns form vertical columns of compacted aggregate through problem soils to increase strength and reduce compressibility. Vibro compaction densifies loose sands using vibratory probes to achieve a denser soil structure. Dynamic compaction improves soil by repeatedly dropping heavy weights onto the ground from heights of 40 to 80 feet.
This document provides an overview of geotechnical engineering and soil mechanics concepts across 5 lectures. It discusses the origin and formation of soils, soil classification systems, phase relationships in soils, permeability, consolidation, shear strength, and soil stabilization techniques. Key topics covered include soil composition, index properties, stress conditions in soil, seepage analysis, compaction, shear strength determination methods, and mechanical and chemical stabilization methods. Real-world engineering applications of soil mechanics are also mentioned.
The document outlines a course plan for a foundation engineering course. It includes 9 units that will be covered: introduction and site investigation, earth pressure, shallow foundations, pile foundations, well foundations, slope stability, retaining walls, and soil stabilization. It provides details on the number of lectures for each unit and the topics that will be covered in each lecture. Some key topics include shallow foundation design methods, pile load testing, earth pressure theories, and slope stability analysis techniques. References for the course are also provided.
The document discusses various types of pavement failures including flexible and rigid pavement failures. For flexible pavements, failures include surface deformation (rutting, corrugation, shoving), cracking (fatigue, transverse, longitudinal), disintegration (potholes, patches), and surface defects (raveling, bleeding). Common causes are poor soil, inferior materials, improper geometry, overloading, and environmental factors. Maintenance techniques to address failures include bituminous surface treatments, asphalt overlays, slurry seals, and crack sealing. For rigid pavements, failures discussed are spalling at joints, scaling of cement concrete, and shrinkage cracks.
This document discusses soil phase systems and relationships between various soil properties. It describes soil as having either a 3-phase or 2-phase system, depending on whether it is partially or fully saturated/dry. The 3-phase system includes volumes and weights of solids, water, and air. Key relationships defined include water content, void ratio, porosity, degree of saturation, dry density, bulk density, and specific gravity. Density index and relative compaction are also explained. Functional relationships are presented between various properties like void ratio, degree of saturation, dry density, specific gravity, and unit weights.
The document provides information about stress distribution in soil due to self-weight and surface loads. It discusses Boussinesq's formula for calculating vertical stress in soil due to a concentrated surface load. The formula shows that vertical stress is directly proportional to the load, inversely proportional to depth squared, and depends on the ratio of radius to depth. A table of coefficient values used in the formula for different ratios of radius to depth is also provided.
Stress distribution in soils can be caused by self-weight of soil layers and surface loads. Stresses increase with depth due to self-weight and decrease radially from applied surface loads. Boussinesq developed equations to determine stresses below concentrated, line, strip and rectangular loads by representing them as point loads and using influence factors. Newmark proposed charts to simplify determining stresses below uniformly loaded areas of different shapes. Approximate methods like the 2:1 method also exist but are less accurate.
1) The document discusses soil bearing capacity, which refers to the capacity of soil to support loads applied to the ground without failing.
2) Important factors in soil bearing capacity include the stability of foundations, which depends on the bearing capacity of soil beneath and the settlement of soil.
3) The document outlines several key terminologies used in soil bearing capacity such as ultimate bearing capacity, net ultimate bearing capacity, net safe bearing capacity, and more.
4) Several methods to increase the bearing capacity of black cotton soil are described, including increasing foundation depth, chemical treatment, grouting, compaction, drainage, and confining the soil.
The document discusses soil consolidation and laboratory consolidation testing. It begins with an introduction to consolidation and describes the three types of soil settlement: immediate elastic settlement, primary consolidation settlement, and secondary consolidation settlement. It then discusses consolidation in more detail, including the spring-cylinder model used to demonstrate consolidation principles. Finally, it describes the process and components of a laboratory oedometer consolidation test.
This document presents a seminar by Anand Singh on soil classification based on the Indian Standard Classification System. It discusses the various soil classification systems and focuses on defining the ISCS. The ISCS classifies soils into four major divisions - coarse grained, fine grained, organic, and peat. It then explains how to classify soils under each division based on factors like grain size, plasticity, liquid limit, and location on a plasticity chart. Examples are provided to demonstrate how to determine the classification symbol of a given soil sample based on test results.
The document describes the California Bearing Ratio (CBR) test procedure used to evaluate the strength of subgrade soils and base courses for pavement design. The CBR test involves compacting a soil sample and measuring the penetration resistance under a constant load over time. Higher CBR values indicate stronger soils that require less thick pavement sections. The document provides details on the test apparatus, sample preparation, soaking, loading and penetration measurements, and CBR calculations according to relevant Indian standards.
This document provides information on index properties, relationships, and tests for soils. It discusses topics like phase diagrams, basic terms and definitions, functional relationships, determination of index properties, and relative density. Phase diagrams for soils that are partially dry/saturated and fully dry/saturated are presented. Key terms like water content, bulk unit weight, dry unit weight, saturated unit weight, specific gravity, void ratio, porosity, degree of saturation are defined. Relationships between these terms and how they relate to volume and mass are also derived. Common methods for determining index properties like water content, specific gravity, and dry density are described.
Aggregates blending, blending aggregates by graphical method, concrete mix design, concrete technology, what is aggregates blending, what is blending, methods of blending, how to blend aggregates, civil engineering
The document discusses different types of geosynthetics including geotextiles, geogrids, geomembranes, and geocomposites. It provides details on their manufacturing processes and applications in civil engineering projects. Geotextiles include woven, nonwoven, knitted, and stitched fabrics that are used for separation, filtration, drainage, reinforcement, and erosion control. Geogrids and geomembranes are stiff polymer sheets used for reinforcement and as barriers. The document outlines common functions of geosynthetics like separation, reinforcement, filtration, drainage, and erosion control. It provides examples of their applications in walls, waste water treatment, and other civil works. Properties discussed include physical characteristics and hydraulic
The document discusses two common soil classification systems: the Unified Soil Classification System (USCS) and the American Association of State Highway and Transportation Officials system (AASHTO). The USCS classifies soils into four major categories based on grain size, plasticity, and compressibility. The AASHTO system classifies soils into eight groups based on particle size distribution, liquid limit, and plasticity index for use in road construction. Both systems provide a standardized way to categorize soils based on simple tests to understand their engineering properties and behavior.
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.
Class notes of Geotechnical Engineering course I used to teach at UET Lahore. Feel free to download the slide show.
Anyone looking to modify these files and use them for their own teaching purposes can contact me directly to get hold of editable version.
Geophysical methods of soil/Foundation testing Pirpasha Ujede
Geophysical methods such as seismic refraction and resistivity testing provide non-invasive subsurface investigation over large areas more quickly and cheaply than traditional boring and testing. However, geophysical results require interpretation and are less definitive. Both methods are important, with geophysical testing used for initial screening and borings to accurately determine soil properties. Seismic refraction uses shock waves to determine layer velocities and depths, while resistivity measures subsurface resistivity variations related to moisture, compaction, and material to infer stratigraphy.
Class notes of Geotechnical Engineering course I used to teach at UET Lahore. Feel free to download the slide show.
Anyone looking to modify these files and use them for their own teaching purposes can contact me directly to get hold of editable version.
Design of flexible pavements as per IRC37 SupriyaPal10
Flexible pavements work by distributing wheel loads across layers to reduce stress. The document discusses flexible pavement design according to Indian Road Congress guidelines for design traffic up to 150 million standard axles. It describes evaluating subgrade strength, calculating design traffic loads, and using CBR and thickness design charts to determine the appropriate flexible pavement layers and thicknesses based on subgrade strength and traffic volume.
This document provides an overview of the Unified Soil Classification System (USCS), including its development, major categories of soils, naming conventions, definitions of grain sizes, procedures for classifying organic soils, and terminology. The USCS is the preferred soil classification system for geotechnical engineers. It categorizes soils based on grain size distribution and plasticity characteristics of the fine fraction. Soils are classified as coarse-grained, fine-grained, or organic, and further designated by specific letters and graphic symbols according to their composition.
The document discusses three soil tests: the liquid limit test determines the moisture content needed for a soil pat to close a groove after 25 drops from 10 mm; the plastic limit test finds the moisture content where a 3 mm soil thread will crumble; and the shrinkage limit test measures the volume and mass of wet and dried soil in a dish to determine moisture loss.
Vibration method for ground improvement techniqueABHISHEK THAKKAE
This document discusses various ground improvement techniques, including vertical drains, soil nailing, stone columns, vibro compaction, and dynamic compaction. Vertical drains accelerate consolidation by facilitating drainage of pore water through columns of pervious material placed in soil. Soil nailing uses steel tendons drilled and grouted into soil to create a reinforced composite mass. Stone columns form vertical columns of compacted aggregate through problem soils to increase strength and reduce compressibility. Vibro compaction densifies loose sands using vibratory probes to achieve a denser soil structure. Dynamic compaction improves soil by repeatedly dropping heavy weights onto the ground from heights of 40 to 80 feet.
This document provides an overview of geotechnical engineering and soil mechanics concepts across 5 lectures. It discusses the origin and formation of soils, soil classification systems, phase relationships in soils, permeability, consolidation, shear strength, and soil stabilization techniques. Key topics covered include soil composition, index properties, stress conditions in soil, seepage analysis, compaction, shear strength determination methods, and mechanical and chemical stabilization methods. Real-world engineering applications of soil mechanics are also mentioned.
The document outlines a course plan for a foundation engineering course. It includes 9 units that will be covered: introduction and site investigation, earth pressure, shallow foundations, pile foundations, well foundations, slope stability, retaining walls, and soil stabilization. It provides details on the number of lectures for each unit and the topics that will be covered in each lecture. Some key topics include shallow foundation design methods, pile load testing, earth pressure theories, and slope stability analysis techniques. References for the course are also provided.
The document discusses various types of pavement failures including flexible and rigid pavement failures. For flexible pavements, failures include surface deformation (rutting, corrugation, shoving), cracking (fatigue, transverse, longitudinal), disintegration (potholes, patches), and surface defects (raveling, bleeding). Common causes are poor soil, inferior materials, improper geometry, overloading, and environmental factors. Maintenance techniques to address failures include bituminous surface treatments, asphalt overlays, slurry seals, and crack sealing. For rigid pavements, failures discussed are spalling at joints, scaling of cement concrete, and shrinkage cracks.
This document discusses soil phase systems and relationships between various soil properties. It describes soil as having either a 3-phase or 2-phase system, depending on whether it is partially or fully saturated/dry. The 3-phase system includes volumes and weights of solids, water, and air. Key relationships defined include water content, void ratio, porosity, degree of saturation, dry density, bulk density, and specific gravity. Density index and relative compaction are also explained. Functional relationships are presented between various properties like void ratio, degree of saturation, dry density, specific gravity, and unit weights.
The document provides information about stress distribution in soil due to self-weight and surface loads. It discusses Boussinesq's formula for calculating vertical stress in soil due to a concentrated surface load. The formula shows that vertical stress is directly proportional to the load, inversely proportional to depth squared, and depends on the ratio of radius to depth. A table of coefficient values used in the formula for different ratios of radius to depth is also provided.
Stress distribution in soils can be caused by self-weight of soil layers and surface loads. Stresses increase with depth due to self-weight and decrease radially from applied surface loads. Boussinesq developed equations to determine stresses below concentrated, line, strip and rectangular loads by representing them as point loads and using influence factors. Newmark proposed charts to simplify determining stresses below uniformly loaded areas of different shapes. Approximate methods like the 2:1 method also exist but are less accurate.
1) The document discusses soil bearing capacity, which refers to the capacity of soil to support loads applied to the ground without failing.
2) Important factors in soil bearing capacity include the stability of foundations, which depends on the bearing capacity of soil beneath and the settlement of soil.
3) The document outlines several key terminologies used in soil bearing capacity such as ultimate bearing capacity, net ultimate bearing capacity, net safe bearing capacity, and more.
4) Several methods to increase the bearing capacity of black cotton soil are described, including increasing foundation depth, chemical treatment, grouting, compaction, drainage, and confining the soil.
The document discusses soil consolidation and laboratory consolidation testing. It begins with an introduction to consolidation and describes the three types of soil settlement: immediate elastic settlement, primary consolidation settlement, and secondary consolidation settlement. It then discusses consolidation in more detail, including the spring-cylinder model used to demonstrate consolidation principles. Finally, it describes the process and components of a laboratory oedometer consolidation test.
This document presents a seminar by Anand Singh on soil classification based on the Indian Standard Classification System. It discusses the various soil classification systems and focuses on defining the ISCS. The ISCS classifies soils into four major divisions - coarse grained, fine grained, organic, and peat. It then explains how to classify soils under each division based on factors like grain size, plasticity, liquid limit, and location on a plasticity chart. Examples are provided to demonstrate how to determine the classification symbol of a given soil sample based on test results.
The document describes the California Bearing Ratio (CBR) test procedure used to evaluate the strength of subgrade soils and base courses for pavement design. The CBR test involves compacting a soil sample and measuring the penetration resistance under a constant load over time. Higher CBR values indicate stronger soils that require less thick pavement sections. The document provides details on the test apparatus, sample preparation, soaking, loading and penetration measurements, and CBR calculations according to relevant Indian standards.
This document provides information on index properties, relationships, and tests for soils. It discusses topics like phase diagrams, basic terms and definitions, functional relationships, determination of index properties, and relative density. Phase diagrams for soils that are partially dry/saturated and fully dry/saturated are presented. Key terms like water content, bulk unit weight, dry unit weight, saturated unit weight, specific gravity, void ratio, porosity, degree of saturation are defined. Relationships between these terms and how they relate to volume and mass are also derived. Common methods for determining index properties like water content, specific gravity, and dry density are described.
Aggregates blending, blending aggregates by graphical method, concrete mix design, concrete technology, what is aggregates blending, what is blending, methods of blending, how to blend aggregates, civil engineering
The document discusses different types of geosynthetics including geotextiles, geogrids, geomembranes, and geocomposites. It provides details on their manufacturing processes and applications in civil engineering projects. Geotextiles include woven, nonwoven, knitted, and stitched fabrics that are used for separation, filtration, drainage, reinforcement, and erosion control. Geogrids and geomembranes are stiff polymer sheets used for reinforcement and as barriers. The document outlines common functions of geosynthetics like separation, reinforcement, filtration, drainage, and erosion control. It provides examples of their applications in walls, waste water treatment, and other civil works. Properties discussed include physical characteristics and hydraulic
The document discusses two common soil classification systems: the Unified Soil Classification System (USCS) and the American Association of State Highway and Transportation Officials system (AASHTO). The USCS classifies soils into four major categories based on grain size, plasticity, and compressibility. The AASHTO system classifies soils into eight groups based on particle size distribution, liquid limit, and plasticity index for use in road construction. Both systems provide a standardized way to categorize soils based on simple tests to understand their engineering properties and behavior.
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.
This document provides an overview of two soil classification systems: the Unified Soil Classification System (USCS) and the American Association of State Highway and Transportation Officials system (AASHTO). It discusses the purpose, key aspects, procedures, and examples of each system. The USCS classifies soils based on grain size and plasticity characteristics into major divisions of coarse-grained, fine-grained, organic, and peat soils. The AASHTO system focuses on classifying soils for road construction into eight groups based on grain size and plasticity, and uses a group index to further evaluate soils within each group.
This document provides an overview of different soil classification systems including: particle size classification, textural classification, Highway Research Board (HRB) classification, Unified Soil Classification System (USCS), and Indian Standard Classification System (ISCS). It describes the key aspects of each system such as group name designations, plasticity characteristics, grain size thresholds. Examples are provided to demonstrate how to classify soils according to their particle sizes, plasticity properties and assign them the appropriate group symbol under different systems.
This ppt is more useful for Civil Engineering students.
I have prepared this ppt during my college days as a part of semester evaluation . Hope this will help to current civil students for their ppt presentations and in many more activities as a part of their semester assessments.
I have prepared this ppt as per the syllabus concerned in the particular topic of the subject, so one can directly use it just by editing their names.
This document discusses two common soil classification systems: the American Association of State Highway and Transportation Officials (AASHTO) system and the Unified Soil Classification System (USCS). It provides details on how each system classifies soils based on grain size distribution and Atterberg limits tests. The AASHTO system uses the group index to further classify soils within groups, while the USCS system specifies symbols for soil type and gradation. The document also discusses classifying organic soils and provides an example of classifying soil using both systems.
Soil classification systems group soils based on their engineering properties and behavior. The document discusses several common soil classification systems including textural classification, Unified Soil Classification System (USCS), Indian Standard (IS) classification, and American Association of State Highway and Transportation Officials (AASHTO) system. The USCS groups soils into coarse-grained (sands and gravels) or fine-grained (silts and clays) based on particle size and plasticity characteristics. Fine-grained soils are further classified on a plasticity chart using liquid limit and plasticity index values. Classification systems provide a standard language for engineers and indicate engineering behavior and properties of soils.
This document provides an overview of two common soil classification systems used in pavement engineering: the Unified Soil Classification System (USCS) and the American Association of State Highway and Transportation Officials system (AASHTO). It describes the purpose, key components, and procedures for classifying soils according to grain size, plasticity characteristics, and other properties in each system. Examples are provided to demonstrate how soil test data can be analyzed and soils assigned appropriate classifications under the USCS and AASHTO systems.
This document provides an overview of soil classification systems, focusing on the Unified Soil Classification System (USCS) and the American Association of State Highway and Transportation Officials (AASHTO) system. It defines key aspects of each system such as grouping soils by grain size and plasticity. Examples are provided to demonstrate how to classify soils using index properties and test results based on the criteria of each system.
This document discusses the classification of soils. It describes the key horizons used to classify soils, including the O, A, E, B, C, and R horizons. The two main classification systems - the Unified Soil Classification System and the American Association of State Highway and Transportation Officials system - are explained. Both systems define grain sizes and use additional properties like color, texture, structure, density, water movement, acidity, and mineral reactivity to classify soils.
This document discusses different methods for classifying soils, including particle size classification, textural classification, Highway Research Board (HRB) classification, Unified Soil Classification System (USCS), and Indian Standard Classification System (ISCS). The key points are:
1) Soils can be classified based on their particle size, texture, engineering properties for pavement or other uses, plasticity characteristics, and percentage of sand, silt and clay.
2) Classification systems group soils with similar properties together to describe and understand their engineering behavior.
3) The ISCS system is based on the USCS but further subdivides fine-grained soils into low, intermediate and high plasticity groups based on
A soil is composed primarily of minerals which are produced from parent material that is weathered or broken into small pieces. Like the classification systems for plants and animals, the soil classification system contains several levels of details, from the most general to the most specific types. The most general level of classification system is the soil order, of which there are 12 major types. This module explains these classes.
The document discusses two common soil classification systems: the Unified Soil Classification System (USCS) and the AASHTO Soil Classification System.
The USCS was developed by Casagrande in 1948 for construction purposes like dams, foundations, and other structures. It characterizes soils into four main groups based on grain size and plasticity characteristics. The AASHTO system was originally developed for classifying soils and aggregates for highway construction. It separates soils into eight major groups based on grain size and plasticity. Both systems use grain size analysis and Atterberg limits tests to classify soils.
This document discusses different systems for classifying soils, including particle size, textural, Highway Research Board (HRB), Unified Soil Classification System (USCS), and Indian Standard Classification System (ISCS). The USCS system divides soils into four main groups - coarse grained, fine grained, organic, and peat. Each soil is designated a two letter symbol based on grain type and plasticity. The ISCS system is similar but subdivides fine grained soils into low, intermediate, and high plasticity groups. Classification involves analyzing particle size distribution and plasticity characteristics on a chart to determine the appropriate group.
This document discusses different soil classification systems including the Unified Soil Classification System (USCS) and the American Association of State Highways and Transportation Officials (AASHTO) system. It provides details on classifying soils based on particle size distribution, liquid limit, and plasticity index using these systems. The USCS uses the No. 200 sieve, liquid limit tests, and plasticity chart to classify soils as gravel, sand, silt, clay, or organic. It also defines key volumetric ratios and properties for soils such as void ratio, saturation, unit weight, and specific gravity.
This document provides an overview of geotechnical engineering testing aspects. It discusses soil classification systems, laboratory tests like moisture content, specific gravity, grain size analysis, Atterberg limits, and field density. Field tests like standard penetration test are also covered. The document outlines the Indian standard soil classification system and 18 soil groups. Key geotechnical parameters and their significance are defined.
The document describes the Indian Standard (IS) Classification System for soils. It divides soils into 3 main categories - coarse grained, fine grained, and highly organic soils - based on grain size. Coarse grained soils are further divided into gravel and sand, each with subcategories based on fines content and plasticity. Fine grained soils are subdivided into low, intermediate, and high compressibility categories based on liquid limit and plasticity index. The document provides detailed explanations of each soil group and examples of classifying soils according to their properties.
A person who cannot blame himself does not blame anyone.
Looking through the lens of infinity is more terrifying than anything.
Where am I and where is all that pettiness!
Amim: full-general
Teri Teri flooded
From bite to evening prayer
Dangal: Vast
Inference: investigation, interrogation
Vomiting: Vomiting
Kefal: Serin
Qalchmaq: Strong
Tallow: Fat
Zanjmore: Crying and wailing
Beginning of page 20 of wall 485
When one has lost the illusion of eternity, it doesn't matter how many hours or how many years you wait. Wall p. 25
It was strange to me that even though he was alive, he let his hair cover his face. Wall p. 32
Tipa tap with the tip of the toe
This document discusses two common soil classification systems: the Unified Soil Classification System (USCS) and the American Association of State Highway and Transportation Officials (AASHTO) system. The USCS classifies soils based on grain size determined through sieve and hydrometer analysis as well as plasticity tests such as the liquid limit and plastic limit. The AASHTO system also considers grain size and plasticity but additionally calculates a group index value. Both systems aim to characterize soils to help evaluate their engineering properties and behavior.
1) Soil classification systems group soils with similar physical properties into units in a systematic way. The Unified Soil Classification System (USCS) and American Association of State Highway and Transportation Officials (AASHTO) systems are commonly used.
2) The USCS and AASHTO systems classify soils based on grain size and plasticity. Soils are categorized as coarse-grained or fine-grained. Parameters like the D10, D30, and D60 values are determined from grain size distribution curves to characterize soils.
3) Under the USCS, soils are given a two-letter symbol indicating major material and gradation/plasticity. For example, well-graded gravel is
1. 1
CE 353 Geotechnical Engineering
Lecture Outline:
1. Classification Systems
2. American Association of State
Highway and Transportation
Officials System (AASHTO)
3. The Unified Soil Classification
System (USCS)
Classification of Soil
Textbook: Braja M. Das, "Principles of Geotechnical Engineering", 7th E. (Chapter 5).
5
Dr M. Touahmia
2. 2
Classification Systems
• Soils in nature rarely exist separately as gravel, sand, silt, clay or organic
matter, but are usually found as mixtures with varying proportions of these
components.
• Classifying soils into groups with similar behavior, in terms of simple indices,
can provide geotechnical engineers a general guidance about engineering
properties of the soils through the accumulated experience.
• Two commonly used systems for Classifying soils based on particle
distribution and Atterberg limits:
1. AASHTO System: American Association of State Highway and Transportation
Officials.
2. USCS: Unified Soil Classification System.
3. 3
AASHTO Soil Classification System
Origin:
• AASHTO system of soil classification was developed by Hogentogler and
Terzaghi in 1929 as the Public Road Administration classification system. It
has undergone several revisions, with the present version proposed by the
Committee on Classification of Materials for Subgrades and Granular Type
Roads of the Highway Research Board in 1945 (ASTM designation D-3282;
AASHTO method M145).
• The system is based on the following three soil properties:
1. Particle-size distribution (AASHTO T-11 and AASHTO T-27 test)
2. Liquid Limit (AASHTO T-89 test).
3. Plasticity Index (AASHTO T-90 test).
4. 4
AASHTO Soil Classification System
• Key Elements:
1. Grain Size:
• Gravel: Fraction passing 75mm sieve and retained on #10 (2mm) US sieve
• Sand: Fraction passing #10 sieve and retained #200 sieve
• Silt and Clay: Fraction passing #200 sieve
2. Plasticity:
• Term silty is applied when fine fractions have a PI < 10
• Term clayey is applied when fine fractions have PI > 11
3. Groups: (see Tables)
• Soils are classified into eight groups, A-1 through A-8.
• The major groups A-1, A-2, and A-3 represent the coarse grained soils.
• The A-4, A-5, A-6, and A-7 represent fine grained soils.
• The A-8 are identified by visual inspection.
6. 6
AASHTO Soil Classification System
• Group Index (GI):
• To evaluate the quality of a soil as a highway subgrade material, one must
incorporate a number called the Group Index (GI) with the groups and
subgroups of the soil. This index is written in parentheses after the group or
subgroup designation. The group index is given by the equation:
where:
F200: % passing #200 sieves expressed as whole number
LL: liquid limit of soil
PI: Plasticity Index of soil
101501.040005.02.035 200200
PIFLLFGI
The first term is
determined by the LL
The second term is
determined by the PI
7. 7
AASHTO Soil Classification System
It may be noted that:
• The higher the value of GI the weaker will be the soil and vice versa. Thus,
quality of performance of a soil as a subgrade material is inversely
proportional to GI.
• A soil having GI of zero is considered as the best.
• If the equation gives negative value for GI, consider it zero.
• Always round off the GI to nearest whole number.
• GI = 0 for soils of groups A-1-a, A-1-b, A-2-4, A-2-5, and A-3.
• For groups A-2-6 and A-2-7 use partial GI for PI only:
101501.0 200
PIFGI
10. 10
AASHTO Soil Classification System
DESCRIPTION OF GROUPS & SUBGROUPS:
• Group A-1: The typical material of this group is a well-graded mixture of
stone fragments or gravels, coarse sand, fine sand, and a non-plastic or
slightly plastic soil binder. This group also includes stone fragments, gravels,
coarse sand, volcanic cinders etc, without a well-graded binder of fine
material.
• Subgroup A-1-a: includes those materials consisting predominantly of stone
fragments or gravel, either with or without a well-graded binder of fine
material.
• Subgroup A-1-b: includes those materials consisting predominantly of coarse
sand with or without a well-graded soil binder.
11. 11
AASHTO Soil Classification System
DESCRIPTION OF GROUPS & SUBGROUPS:
• Group A-3: The typical material of this group is fine beach sand or fine
desert blown sand without silty or clayey fines or with a small amount of
non-plastic silt. This group includes also stream-deposited mixtures of poorly
graded fine sand and limited amounts of coarse sand and gravel.
• Group A-2: This group includes a wide variety of “granular” materials, which
are at the borderline between the materials falling in groups A-1 and A-3
and the silty-clay materials of group A-4 through A-7. It include any materials
not more than 35% of which passes a #200 sieve and which cannot be
classified as A-1 or A-3 because of having fines content or plasticity, or both,
in excess of the limitations for those groups.
12. 12
AASHTO Soil Classification System
DESCRIPTION OF GROUPS & SUBGROUPS:
• Group A-4: The typical material of this group is a non-plastic or moderately
plastic silty soil 75% or more of which usually passes the #200 sieve. The
group also includes mixture of fine silty soil and up to 64% of sand and gravel
retained on the #200 sieve.
• Group A-5:The typical material of this group is similar to that described
under Group A-4, but it may be highly elastic, as indicated by high liquid
limit.
• GroupA-6: The typical material of this group is a plastic clay soil 75% or more
of which usually passes the #200 sieve. The group also includes mixtures of
fine clayey soil and up to 64% of sand and gravel retained on the #200 sieve.
Materials of this group usually have high volume change between wet and
dry states.
13. 13
AASHTO Soil Classification System
DESCRIPTION OF GROUPS & SUBGROUPS:
• Group A-7: The typical material of this group is similar to that described
under Group A-6, but it has the high liquid limits characteristics of the A-5
group and may be elastic as well as subject to high volume change.
• Subgroup A-7-5: includes those materials which have moderate plasticity
indexes in relation to liquid limit and which may be highly elastic as well as
subject to considerable volume change.
• Subgroup A-7-6: includes those materials which have high plasticity indexes
in relation to liquid limit and which are subject to extremely high volume
change.
• Group A-8: The typical material of this group is peat and muck soil ordinarily
found in obviously unstable, swampy areas. Characterized by:
- low density - high compressibility - high water content and - high organic
matter content.
14. 14
Unified Soil Classification System, USCS
• Origin: The Unified Soil Classification system was first developed by
Professor A. Casagrande in 1942 for the purpose of airfield construction
during world War II. Afterwards, it was expended and revised in cooperation
with the U.S. Bureau of Reclamation and the U.S. Army Corps of Engineers so
that it applies not only to airfields but also to embankments, dams,
foundations, and other engineering features. In 1969 the American Society
for Testing and Materials (ASTM) adopted the USCS as a standard method
for classification for engineering purposes (ASTM Test Designation D-2487).
• The USCS is based on the recognition of the type and predominance of the
constituents considering grain-size, gradation, plasticity and compressibility.
It classifies soils into Four major categories:
1. Coarse-grained
2. Fine-grained
3. Organic soils
4. Peat
15. 15
Unified Soil Classification System, USCS
Procedures for Classification:
• From sieve analysis and the grain-size distribution curve determine the
percent passing as the following:
• First, Find % passing # 200.
• If 5% or more of the soil passes the # 200 sieve, then conduct Atterberg
Limits (LL & PL).
• If the soil is fine-grained (≥50% passes #200) follow the guidelines for fine-
grained soils.
• If the soil is coarse-grained (<50% passes #200) follow the guidelines for
coarse-grained soils: Find % Gravel & Sand, calculate Cu & Cc, LL, PL &PI
16. 16
Unified Soil Classification System, USCS
SYMBOLS
Soil symbols:
• G: Gravel
• S: Sand
• M: Silt
• C: Clay
• O: Organic
• Pt: Peat
Liquid limit symbols:
• H: High LL (LL>50)
• L: Low LL (LL<50)
Gradation symbols:
• W: Well-graded
• P: Poorly-graded
)sandsfor(
6Cand3C1
)gravelsfor(
4Cand3C1
soilgradedWell
uc
uc
GROUP SYMBOLS
• The group symbols for coarse-grained gravelly
soils are: GW, GP, GM, GC, GC-GM, GW-GM,
GW-GC, GP-GM, and GP-GC.
• The group symbols for fine-grained soils are:
CL, ML, OL, CH, MH, OH, CL-ML, and Pt.
Example:
SW, Well-graded sand
SC, Clayey sand
SM, Silty sand,
MH, Elastic silt
21. 21
Unified Soil Classification System, USCS
ORGANIC SOILS:
1. Organic clay or silt( group symbol OL or OH):
• If The soil’s liquid limit (LL) after oven drying is less than 75 % of its liquid
limit before oven drying then the first symbol is O.
• The second symbol is obtained by locating the values of PI and LL (not oven
dried) in the plasticity chart.
2. Highly organic soils- Peat (Group symbol Pt):
• A sample composed primarily of vegetable tissue in various stages of
decomposition and has a fibrous to amorphous texture, a dark-brown to
black color, and an organic odor should be designated as a highly organic soil
and shall be classified as peat, Pt.
22. 22
Unified Soil Classification System, USCS
Borderline Cases (Dual Symbols): For the following three conditions,
a dual symbol should be used:
1. Coarse-grained soils with 5% - 12% fines:
• The first symbol indicates whether the coarse fraction is well or poorly
graded. The second symbol describe the contained fines. For example: SP-
SM, poorly graded sand with silt.
2. Fine-grained soils with limits within the shaded zone. (PI between 4 and 7
and LL between about 12 and 25):
• It is hard to distinguish between the silty and more claylike materials.
• CL-ML: Silty clay, SC-SM: Silty, clayed sand.
3. Soil contain similar fines and coarse-grained fractions:
• possible dual symbols GM-ML.