Aggregates are inert materials mixed with cement or lime to make mortar or concrete. They are classified based on size as fine aggregates, which pass through a 4.75mm sieve, or coarse aggregates, which are larger. Common aggregates include sand, gravel, crushed stone, and manufactured lightweight or heavyweight materials. Aggregates are selected based on properties like strength, hardness, durability, and freedom from impurities. Their size, shape, grading, moisture content and other physical properties influence the properties of the concrete.
Lesson: Concrete Technology - Building Materials
The quality of aggregate affect the durability and strength of concrete. Since about 3/4 of the volume of concrete is occupied by aggregate.
This document discusses concrete mix proportioning and design. It provides information on:
1. The different types of mix proportioning including nominal mix and design mix. Nominal mix uses fixed proportions while design mix determines proportions based on fresh and hardened concrete properties.
2. The procedure for mix design according to IS 10262:2009 including determining target mean strength, selecting water-cement ratio, calculating cement and aggregate contents.
3. An example of designing an M30 concrete mix according to the code. The mix had a water-cement ratio of 0.45, cement content of 413kg/m3, fine aggregate content of 724kg/m3 and coarse aggregate content of 1098kg
Concrete Construction: Batching of mixes; casting process, compaction and curing;
requirement of mix design and casting of test cubes – removing cubes from moulds and
curing for strength tests; bar-bending equipments and preparation of reinforcement for
R C C works
This document discusses different types of light weight concrete, including light weight aggregate concrete, aerated concrete, and no-fines concrete. Light weight concrete has lower density than normal concrete, ranging from 300-1850 kg/m3 compared to 2200-2600 kg/m3. It has advantages like reduced dead load, improved workability, and applications in pre-stressed concrete and high-rise buildings. The main methods to produce light weight concrete are using porous aggregates, incorporating air bubbles, or omitting fine aggregates. Properties depend on the type and density, with compressive strengths ranging from 0.3-40 MPa.
Mechanism of different chemical attacks in a concrete like chloride attack, sulfate attack , which causes corrosion and spalling. Other reactions are alkali aggregate reaction , alkali silica reaction in concrete etc.
This document summarizes the classification and properties of aggregates used in construction. It defines aggregates as inert materials mixed with cement or lime for mortar or concrete. Aggregates are classified as fine or coarse based on particle size. Common fine aggregates include sand from various sources, while coarse aggregates include crushed stone and gravel. Key properties discussed include size, shape, composition and performance in tests such as crushing value, impact value and abrasion value. Sieve analysis is also described to determine particle size distribution. An ideal aggregate is characterized as hard, strong, dense and free of impurities to provide durable concrete.
The document discusses various materials used in civil engineering construction projects such as bricks, stones, aggregates, cement, and concrete. It provides details on the manufacturing process and properties of bricks and describes the different types of bricks used. It also discusses the characteristics, classification, and uses of stones as a building material. The qualities, types, and uses of aggregates and cement are outlined. Concrete is introduced as a composite material made by mixing aggregates, sand, cement, and water.
Lesson: Concrete Technology - Building Materials
The quality of aggregate affect the durability and strength of concrete. Since about 3/4 of the volume of concrete is occupied by aggregate.
This document discusses concrete mix proportioning and design. It provides information on:
1. The different types of mix proportioning including nominal mix and design mix. Nominal mix uses fixed proportions while design mix determines proportions based on fresh and hardened concrete properties.
2. The procedure for mix design according to IS 10262:2009 including determining target mean strength, selecting water-cement ratio, calculating cement and aggregate contents.
3. An example of designing an M30 concrete mix according to the code. The mix had a water-cement ratio of 0.45, cement content of 413kg/m3, fine aggregate content of 724kg/m3 and coarse aggregate content of 1098kg
Concrete Construction: Batching of mixes; casting process, compaction and curing;
requirement of mix design and casting of test cubes – removing cubes from moulds and
curing for strength tests; bar-bending equipments and preparation of reinforcement for
R C C works
This document discusses different types of light weight concrete, including light weight aggregate concrete, aerated concrete, and no-fines concrete. Light weight concrete has lower density than normal concrete, ranging from 300-1850 kg/m3 compared to 2200-2600 kg/m3. It has advantages like reduced dead load, improved workability, and applications in pre-stressed concrete and high-rise buildings. The main methods to produce light weight concrete are using porous aggregates, incorporating air bubbles, or omitting fine aggregates. Properties depend on the type and density, with compressive strengths ranging from 0.3-40 MPa.
Mechanism of different chemical attacks in a concrete like chloride attack, sulfate attack , which causes corrosion and spalling. Other reactions are alkali aggregate reaction , alkali silica reaction in concrete etc.
This document summarizes the classification and properties of aggregates used in construction. It defines aggregates as inert materials mixed with cement or lime for mortar or concrete. Aggregates are classified as fine or coarse based on particle size. Common fine aggregates include sand from various sources, while coarse aggregates include crushed stone and gravel. Key properties discussed include size, shape, composition and performance in tests such as crushing value, impact value and abrasion value. Sieve analysis is also described to determine particle size distribution. An ideal aggregate is characterized as hard, strong, dense and free of impurities to provide durable concrete.
The document discusses various materials used in civil engineering construction projects such as bricks, stones, aggregates, cement, and concrete. It provides details on the manufacturing process and properties of bricks and describes the different types of bricks used. It also discusses the characteristics, classification, and uses of stones as a building material. The qualities, types, and uses of aggregates and cement are outlined. Concrete is introduced as a composite material made by mixing aggregates, sand, cement, and water.
The document discusses the design of footings for structures. It begins by explaining that footings are needed to transfer structural loads from members made of materials like steel and concrete to the underlying soil. It then describes different types of shallow and deep foundations, including spread, strap, combined, and raft footings. The document provides details on designing isolated and combined footings to resist vertical loads and moments based on provisions in IS 456. It also discusses wall footings and combined footings that support multiple columns. In summary, the document covers the purpose of footings, various footing types, and design of isolated and combined footings.
Special concrete is used when special properties are more important than normal concrete properties. It is produced using chemical and mineral admixtures added to conventional concrete mixes. There are several types of special concrete including lightweight concrete, high strength concrete, fibre reinforced concrete, ferrocement, ready mix concrete, and others. Each type has specific properties and uses in construction where standard concrete is not suitable.
Workability refers to the ease with which fresh concrete can be mixed, placed, compacted and finished. It is affected by factors like water content, mix proportions, aggregate size and shape, grading and surface texture. Increasing water content or using admixtures improves workability by acting as a lubricant between particles. Larger, rounded aggregates require less water than smaller, angular ones. Well-graded aggregates with minimal voids also increase workability. Workability can be measured using slump, compacting factor, flow, or Vee Bee tests.
This document discusses various soil improvement techniques including lime stabilization, bitumen stabilization, preloading, wick drains, dynamic compaction, deep compaction methods like vibrocompaction and compaction piles, grouting methods, soil freezing, and the use of geotextiles. It provides guidelines for the amount of lime required for stabilization based on soil type. Deep compaction depth depends on factors like tamper weight and impact spacing. Permeation grouting and intrusion grouting are also covered. The document serves as a reference for selecting appropriate soil improvement methods based on soil conditions and project needs.
Stabilization in a broad sense incorporates the various methods employed for modifying the properties of a soil to improve its engineering performance. Stabilization is being used for a variety of engineering works, the most common application being in the construction of road and airfield pavements, where the main objective is to increase the strength or stability of soil and to reduce the construction cost by making best use of locally available materials.
The document provides information on aggregates used in concrete, including their definition, classification, properties, grading, and tests. It defines aggregates as materials such as sand and gravel used to make concrete and mortar. Aggregates are classified by their geological origin, size, and shape. Their properties including strength, absorption, and density are described. The importance of proper grading of aggregates for density and strength of concrete is discussed. Common tests on aggregates like crushing value, impact value, and abrasion value are outlined.
MEANING OF MIX DESIGN
GRADE OF CONCRETE.
FACTORS INFLUCING THE CHOICE OF MIX DESIGN.
MATHODS OF CONCRETE MIX DESIGN
MIX DESIGN BY INDIAN STANDARD METHOD.
The document discusses code provisions for calculating the effective span of slabs according to IS 456. It describes how to calculate the effective span for simply supported, continuous, and cantilever members. It also discusses load assumptions, reinforcement cover requirements, deflection limits, and provides an overview of one-way slabs, two-way slabs, flat slabs, and flat plates.
1. Dowel bars and tie bars are used in concrete pavement design. Dowel bars are placed across transverse joints and transfer loads between slabs while allowing for joint openings. Tie bars are placed longitudinally and prevent transverse cracking and lane separation.
2. The design of dowel bars involves determining the length using an equation considering bar diameter and joint width, and checking that the load transfer capacity meets requirements. Tie bar design involves determining the length based on bar diameter and bond strength, and the spacing is calculated based on the required bar area.
The document discusses different types of lintels and arches used in building construction. It describes lintels as horizontal structural members placed across openings to support the structure above. Various lintel materials include timber, stone, brick, reinforced brick, steel, and reinforced concrete. Arches are structures that span openings and support weight below through arch action. Key arch types include flat, semi-circular, segmental, relieving, parabolic, and others defined by their geometric shape. Arches are classified based on materials like brick, stone, concrete, metal and wood. Factors in arch construction and methods to prevent arch failure are also summarized.
Effect of tendon profile on deflections – Factors
influencing deflections – Calculation of deflections – Short term and long term deflections - Losses
of prestress
The document discusses composite construction using precast prestressed concrete beams and cast-in-situ concrete. It describes how the two elements act compositely after the in-situ concrete hardens. Composite beams can be constructed as either propped or unpropped. Propped construction involves supporting the precast beam during casting to relieve it of the wet concrete weight, while unpropped construction allows stresses to develop under self-weight. Design and analysis of composite beams involves calculating stresses and deflections considering composite action. Differential shrinkage between precast and in-situ concrete also induces stresses.
Concrete is a widely used construction material consisting of cement, water, and aggregates. The strength of concrete is specified using its 28-day cube strength in N/sq.mm. Formwork is used to mold wet concrete into desired shapes and allow it to cure. Formwork design involves choosing traditional or systematic approaches using wood or steel components like props, beams, sheathing to form columns, walls, and beams until the concrete gains sufficient strength. Proper formwork is important for quality concrete finish and structural integrity.
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.
High density concrete, high strength concrete and high performance concrete.shebina a
The document discusses high density concrete, its components, types of aggregates used, admixtures, applications, advantages and disadvantages. High density concrete has a density over 2600 kg/m3 and offers greater strength than regular concrete. Its main components are cement, water, aggregates and admixtures. Natural aggregates come from iron ores while man-made aggregates include iron shots, chilcon and synthetic aggregates. Admixtures like water reducers are used to increase workability and reduce cement and water requirements. High density concrete has applications in radiation shielding, precast blocks, bridges and more due to its high strength and durability.
This document summarizes plastic shrinkage cracking of concrete, which occurs when fresh concrete loses water through evaporation, building up negative pressure. The rate and magnitude of plastic shrinkage depends on factors like bleeding rate, evaporation rate, concrete temperature, and mix constituents.
The document presents a model to calculate plastic shrinkage cracking risk based on four properties: the plastic period duration, bleeding volume, evaporation rate, and use of synthetic microfibers. Risk is classified as low, medium, or high. Methods to reduce risk include shortening the plastic period, increasing bleeding, lowering evaporation, and adding microfibers. In conclusion, the risk assessment considers the plastic period duration, bleeding volume, evaporation rate, and micro
Permeability is the property that governs the rate of flow of a fluid into a porous solid like concrete. The main factors affecting permeability in concrete are the water-cement ratio, cement properties, aggregate size and grading, curing methods, and age of the concrete. A higher water-cement ratio results in more capillary pores in the concrete, increasing permeability. Proper curing and the ongoing hydration process over time causes the permeability of concrete to decrease as capillary pores reduce in size and number. High permeability in concrete can lead to issues like corrosion of reinforcement and damage from frost.
The document summarizes several experiments conducted in a concrete technology lab to test properties of cement and concrete, including fineness of cement, normal consistency of cement, setting time of cement, specific gravity of cement, compressive strength of cement, slump test of concrete, Vee-Bee test of concrete, and compaction factor test of concrete. The experiments are performed according to standard procedures and test methods to determine key properties like workability, consistency, setting behavior, density, and strength.
This document discusses different types of bitumen, asphalt, and tar used in civil engineering materials. It provides details on:
- Bitumen is derived from petroleum distillation and exists in liquid, semi-solid or solid forms. Its main uses include making flexible pavements for roads and waterproofing buildings. The main types of bitumen are straight-run, blown, emulsion, cut-back, and plastic bitumen.
- Asphalt is a mixture of bitumen and inert materials left after petroleum distillation. It is used mainly in road construction. The two types are natural asphalt found in lakes/rocks, and residual asphalt from petroleum distillation.
Aggregates are a combination of different sized stones used in construction. They are classified based on size, source, and density. Fine aggregates are less than 5mm while coarse aggregates are greater than 5mm. Natural aggregates come from sources like rivers while manufactured aggregates are crushed. Normal weight aggregates have densities from 1520-1680kg/m3 while lightweight aggregates are less than 1120kg/m3. Tests are conducted to determine properties like strength, hardness, durability and water absorption. Sieve analysis tests the grading and ensures a range of aggregate sizes are present.
Aggregates are a combination of different sized stones used in construction. They are classified based on size, source, and density. Common types include natural and crushed coarse and fine aggregates. Aggregates must be hard, durable, and free of organic matter or other impurities. Tests are conducted to determine properties like strength, hardness, porosity, and water absorption. Sieve analysis tests the particle size distribution and grading of aggregates.
The document discusses the design of footings for structures. It begins by explaining that footings are needed to transfer structural loads from members made of materials like steel and concrete to the underlying soil. It then describes different types of shallow and deep foundations, including spread, strap, combined, and raft footings. The document provides details on designing isolated and combined footings to resist vertical loads and moments based on provisions in IS 456. It also discusses wall footings and combined footings that support multiple columns. In summary, the document covers the purpose of footings, various footing types, and design of isolated and combined footings.
Special concrete is used when special properties are more important than normal concrete properties. It is produced using chemical and mineral admixtures added to conventional concrete mixes. There are several types of special concrete including lightweight concrete, high strength concrete, fibre reinforced concrete, ferrocement, ready mix concrete, and others. Each type has specific properties and uses in construction where standard concrete is not suitable.
Workability refers to the ease with which fresh concrete can be mixed, placed, compacted and finished. It is affected by factors like water content, mix proportions, aggregate size and shape, grading and surface texture. Increasing water content or using admixtures improves workability by acting as a lubricant between particles. Larger, rounded aggregates require less water than smaller, angular ones. Well-graded aggregates with minimal voids also increase workability. Workability can be measured using slump, compacting factor, flow, or Vee Bee tests.
This document discusses various soil improvement techniques including lime stabilization, bitumen stabilization, preloading, wick drains, dynamic compaction, deep compaction methods like vibrocompaction and compaction piles, grouting methods, soil freezing, and the use of geotextiles. It provides guidelines for the amount of lime required for stabilization based on soil type. Deep compaction depth depends on factors like tamper weight and impact spacing. Permeation grouting and intrusion grouting are also covered. The document serves as a reference for selecting appropriate soil improvement methods based on soil conditions and project needs.
Stabilization in a broad sense incorporates the various methods employed for modifying the properties of a soil to improve its engineering performance. Stabilization is being used for a variety of engineering works, the most common application being in the construction of road and airfield pavements, where the main objective is to increase the strength or stability of soil and to reduce the construction cost by making best use of locally available materials.
The document provides information on aggregates used in concrete, including their definition, classification, properties, grading, and tests. It defines aggregates as materials such as sand and gravel used to make concrete and mortar. Aggregates are classified by their geological origin, size, and shape. Their properties including strength, absorption, and density are described. The importance of proper grading of aggregates for density and strength of concrete is discussed. Common tests on aggregates like crushing value, impact value, and abrasion value are outlined.
MEANING OF MIX DESIGN
GRADE OF CONCRETE.
FACTORS INFLUCING THE CHOICE OF MIX DESIGN.
MATHODS OF CONCRETE MIX DESIGN
MIX DESIGN BY INDIAN STANDARD METHOD.
The document discusses code provisions for calculating the effective span of slabs according to IS 456. It describes how to calculate the effective span for simply supported, continuous, and cantilever members. It also discusses load assumptions, reinforcement cover requirements, deflection limits, and provides an overview of one-way slabs, two-way slabs, flat slabs, and flat plates.
1. Dowel bars and tie bars are used in concrete pavement design. Dowel bars are placed across transverse joints and transfer loads between slabs while allowing for joint openings. Tie bars are placed longitudinally and prevent transverse cracking and lane separation.
2. The design of dowel bars involves determining the length using an equation considering bar diameter and joint width, and checking that the load transfer capacity meets requirements. Tie bar design involves determining the length based on bar diameter and bond strength, and the spacing is calculated based on the required bar area.
The document discusses different types of lintels and arches used in building construction. It describes lintels as horizontal structural members placed across openings to support the structure above. Various lintel materials include timber, stone, brick, reinforced brick, steel, and reinforced concrete. Arches are structures that span openings and support weight below through arch action. Key arch types include flat, semi-circular, segmental, relieving, parabolic, and others defined by their geometric shape. Arches are classified based on materials like brick, stone, concrete, metal and wood. Factors in arch construction and methods to prevent arch failure are also summarized.
Effect of tendon profile on deflections – Factors
influencing deflections – Calculation of deflections – Short term and long term deflections - Losses
of prestress
The document discusses composite construction using precast prestressed concrete beams and cast-in-situ concrete. It describes how the two elements act compositely after the in-situ concrete hardens. Composite beams can be constructed as either propped or unpropped. Propped construction involves supporting the precast beam during casting to relieve it of the wet concrete weight, while unpropped construction allows stresses to develop under self-weight. Design and analysis of composite beams involves calculating stresses and deflections considering composite action. Differential shrinkage between precast and in-situ concrete also induces stresses.
Concrete is a widely used construction material consisting of cement, water, and aggregates. The strength of concrete is specified using its 28-day cube strength in N/sq.mm. Formwork is used to mold wet concrete into desired shapes and allow it to cure. Formwork design involves choosing traditional or systematic approaches using wood or steel components like props, beams, sheathing to form columns, walls, and beams until the concrete gains sufficient strength. Proper formwork is important for quality concrete finish and structural integrity.
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.
High density concrete, high strength concrete and high performance concrete.shebina a
The document discusses high density concrete, its components, types of aggregates used, admixtures, applications, advantages and disadvantages. High density concrete has a density over 2600 kg/m3 and offers greater strength than regular concrete. Its main components are cement, water, aggregates and admixtures. Natural aggregates come from iron ores while man-made aggregates include iron shots, chilcon and synthetic aggregates. Admixtures like water reducers are used to increase workability and reduce cement and water requirements. High density concrete has applications in radiation shielding, precast blocks, bridges and more due to its high strength and durability.
This document summarizes plastic shrinkage cracking of concrete, which occurs when fresh concrete loses water through evaporation, building up negative pressure. The rate and magnitude of plastic shrinkage depends on factors like bleeding rate, evaporation rate, concrete temperature, and mix constituents.
The document presents a model to calculate plastic shrinkage cracking risk based on four properties: the plastic period duration, bleeding volume, evaporation rate, and use of synthetic microfibers. Risk is classified as low, medium, or high. Methods to reduce risk include shortening the plastic period, increasing bleeding, lowering evaporation, and adding microfibers. In conclusion, the risk assessment considers the plastic period duration, bleeding volume, evaporation rate, and micro
Permeability is the property that governs the rate of flow of a fluid into a porous solid like concrete. The main factors affecting permeability in concrete are the water-cement ratio, cement properties, aggregate size and grading, curing methods, and age of the concrete. A higher water-cement ratio results in more capillary pores in the concrete, increasing permeability. Proper curing and the ongoing hydration process over time causes the permeability of concrete to decrease as capillary pores reduce in size and number. High permeability in concrete can lead to issues like corrosion of reinforcement and damage from frost.
The document summarizes several experiments conducted in a concrete technology lab to test properties of cement and concrete, including fineness of cement, normal consistency of cement, setting time of cement, specific gravity of cement, compressive strength of cement, slump test of concrete, Vee-Bee test of concrete, and compaction factor test of concrete. The experiments are performed according to standard procedures and test methods to determine key properties like workability, consistency, setting behavior, density, and strength.
This document discusses different types of bitumen, asphalt, and tar used in civil engineering materials. It provides details on:
- Bitumen is derived from petroleum distillation and exists in liquid, semi-solid or solid forms. Its main uses include making flexible pavements for roads and waterproofing buildings. The main types of bitumen are straight-run, blown, emulsion, cut-back, and plastic bitumen.
- Asphalt is a mixture of bitumen and inert materials left after petroleum distillation. It is used mainly in road construction. The two types are natural asphalt found in lakes/rocks, and residual asphalt from petroleum distillation.
Aggregates are a combination of different sized stones used in construction. They are classified based on size, source, and density. Fine aggregates are less than 5mm while coarse aggregates are greater than 5mm. Natural aggregates come from sources like rivers while manufactured aggregates are crushed. Normal weight aggregates have densities from 1520-1680kg/m3 while lightweight aggregates are less than 1120kg/m3. Tests are conducted to determine properties like strength, hardness, durability and water absorption. Sieve analysis tests the grading and ensures a range of aggregate sizes are present.
Aggregates are a combination of different sized stones used in construction. They are classified based on size, source, and density. Common types include natural and crushed coarse and fine aggregates. Aggregates must be hard, durable, and free of organic matter or other impurities. Tests are conducted to determine properties like strength, hardness, porosity, and water absorption. Sieve analysis tests the particle size distribution and grading of aggregates.
REPORT-AGGREGATE and TYPES OF AGGREGATE (1).pptxlordperez2
Aggregates make up 70-80% of concrete and come in two sizes: fine aggregates (passed through a 4.75mm sieve) and coarse aggregates (retained on a 4.75mm sieve). Aggregates can be natural, originating from weathered rock, or artificial, produced by heating materials like clay or shale. Aggregates are also classified by shape, including rounded, irregular, angular, flaky, and elongated. Proper handling and storage of aggregates is important to prevent contamination or changes in grading.
This document discusses aggregates and mortar. It defines aggregates as granular materials used in concrete, which occupy 70-80% of concrete volume. Aggregates are classified based on size, source, unit weight, and shape. Tests conducted on aggregates include particle size, impact value, crushing value, and abrasion value. Mortar is made by mixing a binding material, fine aggregate, and water. The types of mortar discussed are cement mortar, lime mortar, mud mortar, lightweight mortar, and fire resistant mortar. Mortar properties like workability, water retention, stiffening, and strength are also covered.
Aggregates are granular materials like sand, gravel, or crushed stone used with water and cement to make concrete. They come in two sizes: fine aggregates smaller than 5 mm and coarse aggregates larger than 5 mm. Aggregates provide strength, reduce cracking, and lower the cost of concrete. They are selected based on being hard, durable, and free of organic materials or other substances that could weaken the concrete. Aggregates are classified by size, manufacturing method, and density. Physical tests are conducted to determine properties like strength, hardness, porosity, and grading.
This document discusses different types and properties of aggregates used in concrete. It defines aggregates as granular materials such as sand, gravel, or crushed stone. Aggregates can be classified based on size, source, unit weight, and shape. Coarse aggregates are larger than 4.75mm while fine aggregates pass through a 4.75mm sieve. Key properties of aggregates that influence concrete include water absorption, bulk density, specific gravity, surface texture, and size/shape distribution. Proper aggregate selection and testing is important for producing high quality, high strength concrete.
This document provides an overview of brick manufacturing and fly ash utilization. It discusses the constituents of brick earth and fly ash, as well as the manufacturing process which involves preparing clay, molding bricks, drying, and burning. Field testing methods for bricks are outlined. Characteristics of a first class brick and quality testing methods are also described. The document then covers how fly ash is disposed of from power plants and potential applications in construction, including advantages and disadvantages of fly ash use. Fly ash bricks are one highlighted application.
This document discusses the key ingredients and properties of concrete. It describes cement, aggregates, grades of concrete, and concrete mix design. The main constituents of concrete are cement, fine aggregate, coarse aggregate, and water. Cement provides the binding properties and comes in various types. Aggregates occupy 70-75% of the concrete volume and influence properties. Concrete mix design considers the grading, moisture content, and properties of aggregates. Different grades of concrete provide varying compressive strengths suited for construction needs.
B-Tech Construction Material Presentaion.pptmosesnhidza
This document provides an overview of concrete, including its definition, properties, composition, testing, and uses. Some key points:
- Concrete is a mixture of cement, aggregates (sand and gravel), and water that can be used for load-bearing construction.
- Its properties depend on the mix proportions, water-cement ratio, and type of aggregates used. Good compaction and curing are important for strength.
- Concrete has high compressive strength but low tensile strength, so it is often reinforced with steel bars or prestressed using steel tendons.
- Aggregates make up the majority of a concrete mix by weight and influence properties like strength and durability. Proper testing of aggregates is
Classification, properties and extraction of AggregatesZeeshan Afzal
Aggregate:
Aggregates are defined as inert, granular, and inorganic material that normally consist of stone or stone like solids.
Aggregates are used :
In road bases as Asphalt Aggregates.
With ordinary Portland cement(OPC) as normal aggregates as fills in foundations and as aggregate accordingly to project specific studies.
About three-fourth (75%) of the volume of Portland cement concrete is occupied by aggregates. Other 25% include cementing materials like cement, sand and synthetic admixtures.Asphalt cement concrete occupy 90% or more of the total volume. The remaining portion is mainly sand and Bitumen which acts as cementing material in is Asphalt Aggregates.
Road Aggregate
Road aggregate are the non-active inert material used to provide mass to the base and sub-base courses.
Road aggregate should have high strength to bear the traffic load.
Road aggregates must have higher impact value to withstand the Tyre impact phenomenon.
By volume, aggregate generally account for 92 to 96% of bituminous concrete.
Road aggregates should have relatively:
High strength
High resistance to impact & abrasion
Impermeable
Chemically inert
Low coefficient of expansion
Concrete Aggregate:
Portland cement concrete occupy volume of about 70-80% of aggregates.
Fine aggregates are used in making thin concrete slabs where a smooth surface is required. Fine aggregate is commonly known as Pan.
Coarse aggregate is used for more massive members.
Fine aggregates are used in making thin concrete slabs where a smooth surface is required. Fine aggregate is commonly known as Pan.
Coarse aggregate is used for more massive members.
Fine aggregates are used in making thin concrete slabs where a smooth surface is required. Fine aggregate is commonly known as Pan.
Coarse aggregate is used for more massive members.
Siliceous material in aggregates
The siliceous materials are Opal, Chalcedony, Flint & Volcanic Glass.
These siliceous materials have Deleterious reaction, if high alkali-cement is used.
This can be avoided by using low alkali-cement and also by adding Pozzolana to the Mix.
Alkali-aggregate reaction can also occur
The percentage of strained Quartz in the aggregate also have deleterious reaction.
If Percentage of Strained Quartz is >40%, were highly reative.
Between 30-35% were moderate reative.
Argillaceous dolostones ( containing clay minerals) may expand when used with high alkali-cement.
The expansion is due to uptake moisture by the clay minerals.
This document provides information on aggregates used in traditional building materials. It defines aggregates as fillers used with binding materials that are derived from rocks. Aggregates make up 70-80% of concrete's volume and influence its properties. Aggregates are broadly classified into fine aggregates smaller than 4.75mm and coarse aggregates larger than 4.75mm. The document discusses various types of coarse aggregates based on geological origin, size, shape, and unit weight. It also covers properties of aggregates like strength, shape, specific gravity, moisture content and tests conducted on aggregates. Alkali aggregate reaction and measures to prevent it are summarized.
1) The document discusses different types of aggregates used in construction including their classification, physical properties, and testing methods.
2) Aggregates are classified based on size, source, and density. Common physical properties examined include shape, texture, strength, specific gravity, porosity, and moisture content.
3) Key tests described are for crushing strength, impact value, abrasion resistance, specific gravity, absorption, and moisture content. Proper testing ensures aggregates meet requirements for uses like concrete.
This document provides an overview of various civil engineering materials including timber, sand, aggregate, mortar, and concrete. It discusses the types, properties, requirements and uses of each material. Timber types include hardwood and softwood. Sand is classified as fine, medium, or coarse. Aggregate can be natural or artificial, and classified by size as fine or coarse aggregate. Mortar requirements include workability and water retention. Mortar types include cement, lime, lightweight, fire resistant, and mud mortar. Concrete uses cement, water, aggregates and sometimes admixtures to bond together with strength, durability and versatility.
The document summarizes the key properties and classifications of aggregates used to make concrete. It discusses that aggregates provide bulk and strength to concrete. It classifies aggregates based on their geological origin, size, shape, grading, and unit weight. The summary properties of fine and coarse aggregates are also provided, including requirements for good aggregates.
This document discusses materials used in highway construction including aggregates, bitumen, asphalt, cement, and steel reinforcement. It provides details on the composition, production, and properties of these materials. Aggregates include sand, gravel, and crushed stone. Bitumen and asphalt are refined from crude oil and used to bind aggregates in asphalt concrete. Cement is produced by heating limestone and clay and is the binding agent in concrete. Steel reinforcement provides tensile strength to concrete.
CIVIL ENGINEERING CONSTRUCTIONS MATERIALS LOUIS WAYNE
This document provides information on various civil engineering materials including timber, sand, aggregate, mortar, and concrete. It discusses the types, properties, requirements and uses of each material. Timber types include hardwood and softwood. Sand is classified as fine, medium, and coarse. Aggregates can be natural or artificial, and are classified by size as fine or coarse aggregates. Mortar types include cement mortar, lime mortar, light weight mortar, fire resistant mortar, and mud mortar. Concrete types depend on mix design and include regular concrete, high strength concrete, self-consolidating concrete, and others. Each material has important applications in construction.
This document provides information on self-compacting concrete (SCC) and light-weight concrete. It defines SCC as concrete that can flow and fill formwork without vibration due to its high fluidity. Benefits of SCC include faster construction, improved quality, and a safer work environment. Light-weight concrete is defined as having a density of less than 2200kg/m3, containing porous aggregates, and including an expanding agent. Examples of structures built with SCC include Burj Dubai and an airport control tower in Stockholm. Requirements for producing SCC and light-weight concrete are also outlined.
The document discusses reinforced cement concrete (RCC), including its history, materials, specifications, and advantages/disadvantages. RCC uses steel reinforcement embedded in concrete to resist tensile, shear, and sometimes compressive stresses. François Coignet is considered a pioneer of RCC, building the first reinforced concrete structure in 1853. Proper proportions and mixing of cement, aggregates like sand and gravel, and water are needed to produce durable concrete. Precast concrete involves casting pieces off-site then transporting them for assembly.
Concrete is made up of ingredients like Cement, Fine Aggregate (Sand), Coarse Aggregate, Water and admixtures. Concrete mix design is done to Optimize the requirements of Cement, Sand, Aggregate and Water in order to ensure that concrete parameters in both Plastic Stage (like workability) and in Hardened Stage (like Compressive Strength and durability) are achieved. The Concrete mix design is as per Indian Standards (IS 10262) and might vary from country to country. The nominal mix design ratios available for concrete less than M30 in strength are only thumb rules and are generally over designed. As the actual site conditions vary and the mix design should be adjusted as per the location and other factors.
This project proposal seeks funding to analyze swelling clay near Tribhuvan International Airport (TIA) in Kathmandu and reconstruct a damaged road. The proposal outlines collecting soil samples from within 2-4 meters of the surface, testing the samples to determine soil consistency, clay content, and mineral composition, and reconstructing the road with a safety factor over 1. The total anticipated budget is 250,000 Nepali rupees.
Presentation of TU students, 2018 at Ehime UniversityJyoti Khatiwada
The 19-day JST Sakura program provided students from Nepal with hands-on learning experiences in Japan. Key activities included:
1. Conducting microtremor data acquisition and interpretation to study soil properties.
2. Visiting disaster areas from the Kumamoto earthquake and learning mitigation techniques.
3. Performing soil laboratory tests including triaxial compression, ring shear, and centrifuge tests to study soil mechanics.
4. Learning about Japanese culture, traffic management, and waste segregation through daily experiences.
This document is a proposal for a dissertation examining the activity and consolidation of Kathmandu Clay. It has been approved by Dr. Ranjan Kumar Dahal of Tribhuvan University as partial fulfillment of an MSc in Engineering Geology. The proposal provides background on the geology and soil composition of the Kathmandu Valley. It reviews previous literature on the properties of Kathmandu Clay. The objectives are to study the activity and consolidation behavior of the clay. Fieldwork, laboratory testing, and analysis of Atterberg limits, liquidity index, and activity will be conducted. The expected outcomes are improved understanding of the clay's properties and behavior to inform geotechnical engineering applications.
Slope inclinometers are used to monitor landslides by measuring the magnitude, rate, direction, and depth of landslide movement. They consist of an inclinometer casing installed below a landslide and an inclinometer probe that measures the tilt of the casing. Changes in tilt measurements over time indicate how much and in what direction the ground around the casing is moving. However, accurate inclinometer measurements require proper installation below the potential failure zone and accounting for potential errors in the data from bias shifts, sensitivity drifts, rotation of the casing, and inaccuracies in probe depth readings.
This document provides an overview of the finite element method (FEM) for a course on engineering geology. It outlines the course content, which includes an introduction to FEM, the Ritz-Galerkin and weak form methods, and applying FEM to 1D and 2D problems. Key aspects of FEM discussed include reducing partial differential equations to a system of algebraic equations, dividing problems into finite elements, and constructing approximate functions and element matrices. The origins and importance of FEM for solving complex problems are also summarized.
The document discusses various factors that affect slope stability and methods to determine slope stability. It addresses how gravitational forces, water, earthquake activity, slope angle, and rock structures can impact stability. Specific triggers for landslides include rainfall, erosion, construction activities, and earthquakes. Slope stability is determined by calculating the factor of safety, which compares resisting and driving shear forces based on a slope's cohesion, internal friction, and other properties. A factor of safety below 1 indicates a slope is unstable.
Drilling and blasting involves different types of drilling like rotary and percussive drilling. Rotary drilling uses tricone bits and drag bits while percussive uses hammers. Factors like burden, spacing, stemming affect blast design. Explosives like TNT, dynamite and safety fuses are used. Blasted rocks undergo processes like radial cracking and flexural rupture. Controlled blasting techniques like presplitting and cushion blasting reduce overbreak. Explosives have risks but when used properly can efficiently fracture rocks for excavation.
This document provides an introduction to key concepts in hydrogeology. It defines hydrogeology as the study of groundwater distribution and movement in relation to geology. Key topics covered include the hydrologic cycle, parameters for evaluating surface and groundwater, common groundwater issues, and aquifer types. Groundwater resources are a small percentage of available freshwater. Proper management of surface and groundwater is important to address problems like depletion, subsidence, and pollution.
Groundwater, or water located beneath the Earth's surface, is an important source of freshwater. It is found in the pores and cracks of soil, sand, and rock below the water table. Groundwater hydrology is the study of groundwater movement and storage. Key aspects include aquifers, which are geologic formations that can store and transmit water; recharge from precipitation; and groundwater flow through aquifers driven by gravity and the hydraulic gradient. Mapping groundwater involves measuring water levels in wells to determine the piezometric surface and direction of subsurface flow. Sustainable groundwater use requires understanding recharge rates and connections to surface water.
This document discusses different types of drill bits used in drilling operations including their advantages and disadvantages. It summarizes that there are two main types of drill bits: drag bits and roller cutter bits. Drag bits have fixed cutting blades while roller cutter bits have rotating cones containing cutting elements. The document then describes various bit designs within each category including steel tooth bits, tungsten carbide insert bits, diamond bits, and polycrystalline diamond compact bits. It concludes by discussing factors that affect bit performance and wear such as bearing wear, gauge wear, and tooth wear or loss.
The document discusses stresses around underground openings such as tunnels. It describes how underground openings alter the initial stress state of rocks and how determining stresses is important for design. Different types of tunnels and excavation methods are also outlined. The document then focuses on analyzing stresses around circular underground openings using transformations between rectangular and polar coordinate systems. It presents solutions for circular openings under hydrostatic stress fields and discusses elastic-plastic behavior, including Bray's model for analyzing squeezing tunnels.
The document discusses several failure criteria for rocks, including:
1) The Mohr-Coulomb criterion, which defines shear strength as a function of cohesion and friction angle.
2) The Hoek-Brown criterion, which models the non-linear relationship between principal stresses and incorporates rock mass quality.
3) The Griffith failure criterion, which postulates that stress concentrations at flaws like cracks cause propagation and failure.
It also briefly mentions the Drucker-Prager yield criterion and that empirical criteria tailored to a specific rock type may provide the most precise failure prediction.
The document discusses dams, including their purposes, types, and factors to consider for site selection and investigation. It provides information on different types of dams including earth, rock, concrete, gravity, arch, buttress, and composite dams. Key factors for dam site selection and investigation include geological conditions, hydrology, availability of construction materials, and environmental impacts. Detailed geological investigations are necessary to evaluate the foundation stability, water tightness of the reservoir, and availability of local construction materials.
Geophysical prospecting uses physical methods to study the structure of the Earth's crust and locate minerals and ores. It involves collecting data using geophysical methods like seismic, gravitational, magnetic, electrical, and electromagnetic surveys. Seismic methods are commonly used in exploration. They involve generating seismic waves using sources like sledgehammers and analyzing the reflected and refracted waves detected by receivers to characterize subsurface layers and locate resources based on their elastic properties. Proper data acquisition, processing to reduce noise, and geological interpretation of processed seismic data are required to build an accurate model of the subsurface.
Similarities between gravity and magnetics and application of different geoph...Jyoti Khatiwada
The document discusses similarities and differences between gravity and magnetic geophysical survey methods. Some key similarities are that both measure naturally occurring fields of the Earth (gravity and magnetic), both use identical physical and mathematical representations, and data acquisition/reduction/interpretation are similar. Key differences include magnetic susceptibility varying more than density, magnetic forces can be attractive or repulsive while gravity is always attractive, and the magnetic field is time-dependent unlike gravity.
This document discusses different types of groundwater pumps. It begins by introducing various pump classifications and descriptions. It then focuses on pumps used for groundwater, dividing them into three main categories: 1) hand and treadle pumps which are manually operated, 2) low pressure suction pumps which use suction to pull water from shallow depths, and 3) high pressure suction pumps, which include centrifugal pumps that use rotation to move water and positive displacement pumps that use expanding cavities to move water at constant volumes. The document provides details on the design and operation of centrifugal and positive displacement pumps. It concludes by mentioning submersible pumps and jet pumps as other groundwater pump options.
To determine the particle size distribution of soil by hydrometer methodJyoti Khatiwada
This document outlines the hydrometer method for determining particle size distribution of soils passing a 75 sieve. Key steps include: 1) calibrating the hydrometer to relate readings to particle sizes, 2) preparing a soil suspension and taking hydrometer readings at intervals as particles settle, and 3) using the readings to calculate particle sizes and percentage of soil finer than each size. The process provides critical information about soil composition for purposes like engineering projects.
To determine specific gravity of the solids by density bottle methodJyoti Khatiwada
This document outlines the density bottle method for determining the specific gravity of solids. Key steps include: (1) weighing an empty bottle and the bottle containing a dried soil sample, (2) adding water and applying a vacuum to remove air bubbles, (3) weighing the bottle containing the soil sample and water, and (4) calculating the specific gravity by dividing the mass of the solids by the mass of the displaced water. Specific gravity is an important property that indicates the density of a solid relative to the density of water.
To determine dry density of soil by core cutter methodJyoti Khatiwada
This document provides instructions for determining the dry density of soil using a core cutter method. Key steps include:
1) Pressing a cylindrical core cutter into the soil mass to extract a soil sample.
2) Weighing the soil sample and calculating its mass.
3) Determining the water content of a representative subsample.
4) Using the measured mass and known volume of the core cutter, along with the water content, to calculate the dry density of the soil according to the specified formula.
Rock mechanics for engineering geology part 3Jyoti Khatiwada
Hydraulic fracturing is a method to estimate initial stresses by pressurizing a sealed borehole section until it fractures. The fracture orientation indicates the minimum stress direction. This provides the orientation of the maximum horizontal stress for vertical boreholes. The breakdown pressure estimates the minimum principal stress, while the reopening pressure estimates the maximum principal stress. This allows estimating the 2D stress field in the horizontal plane, making it suitable for deep measurements where no underground access exists. However, it requires space for equipment and is best suited to vertical boreholes.
This presentation offers a general idea of the structure of seed, seed production, management of seeds and its allied technologies. It also offers the concept of gene erosion and the practices used to control it. Nursery and gardening have been widely explored along with their importance in the related domain.
إتصل على هذا الرقم اذا اردت الحصول على "حبوب الاجهاض الامارات" توصيلنا مجاني رقم الواتساب 00971547952044:
00971547952044. حبوب الإجهاض في دبي | أبوظبي | الشارقة | السطوة | سعر سايتوتك Cytotec يتميز دواء Cytotec (سايتوتك) بفعاليته في إجهاض الحمل. يمكن الحصول على حبوب الاجهاض الامارات بسهولة من خلال خدمات التوصيل السريع والدفع عند الاستلام. تُستخدم حبوب سايتوتك بشكل شائع لإنهاء الحمل غير المرغوب فيه. حبوب الاجهاض الامارات هي الخيار الأمثل لمن يبحث عن طريقة آمنة وفعالة للإجهاض المنزلي.
تتوفر حبوب الاجهاض الامارات بأسعار تنافسية، ويمكنك الحصول على خصم كبير عند الشراء الآن. حبوب الاجهاض الامارات معروفة بقدرتها الفعالة على إنهاء الحمل في الشهر الأول أو الثاني. إذا كنت تبحث عن حبوب لتنزيل الحمل في الشهر الثاني أو الأول، فإن حبوب الاجهاض الامارات هي الخيار المثالي.
دواء سايتوتك يحتوي على المادة الفعالة ميزوبروستول، التي تُستخدم لإجهاض الحمل والتخلص من النزيف ما بعد الولادة. يمكنك الآن الحصول على حبوب سايتوتك للبيع في دبي وأبوظبي والشارقة من خلال الاتصال برقم 00971547952044. نسعى لتقديم أفضل الخدمات في مجال حبوب الاجهاض الامارات، مع توفير حبوب سايتوتك الأصلية بأفضل الأسعار.
إذا كنت في دبي، أبوظبي، الشارقة أو العين، يمكنك الحصول على حبوب الاجهاض الامارات بسهولة وأمان. نحن نضمن لك وصول الحبوب الأصلية بسرية تامة مع خيار الدفع عند الاستلام. حبوب الاجهاض الامارات هي الحل الفعال لإنهاء الحمل غير المرغوب فيه بطريقة آمنة.
تبحث العديد من النساء في الإمارات العربية المتحدة عن حبوب الاجهاض الامارات كبديل للعمليات الجراحية التي تتطلب وقتاً طويلاً وتكلفة عالية. بفضل حبوب الاجهاض الامارات، يمكنك الآن إنهاء الحمل بسلام وأمان في منزلك. نحن نوفر حبوب الاجهاض الامارات الأصلية من إنتاج شركة فايزر، مما يضمن لك الحصول على منتج فعال وآمن.
إذا كنت تبحث عن حبوب الاجهاض الامارات في العين، دبي، أو أبوظبي، يمكنك التواصل معنا عبر الواتس آب أو الاتصال على رقم 00971547952044 للحصول على التفاصيل حول كيفية الشراء والتوصيل. حبوب الاجهاض الامارات متوفرة بأسعار تنافسية، مع تقديم خصومات كبيرة عند الشراء بالجملة.
حبوب الاجهاض الامارات هي الخيار الأمثل لمن تبحث عن وسيلة آمنة وسريعة لإنهاء الحمل غير المرغوب فيه. تواصل معنا اليوم للحصول على حبوب الاجهاض الامارات الأصلية وتجنب أي مشاكل أو مضاعفات صحية.
في النهاية، لا تقلق بشأن الحبوب المقلدة أو الخطرة، فنحن نوفر لك حبوب الاجهاض الامارات الأصلية بأفضل الأسعار وخدمة التوصيل السريع والآمن. اتصل بنا الآن على 00971547952044 لتأكيد طلبك والحصول على حبوب الاجهاض الامارات التي تحتاجها. نحن هنا لمساعدتك وتقديم الدعم اللازم لضمان حصولك على الحل المناسب لمشكلتك.
Cultivation of human viruses and its different techniques.MDAsifKilledar
Viruses are extremely small, infectious agents that invade cells of all types. These have been culprits in many human disease including small pox,flu,AIDS and ever present common cold as well as plants bacteria and archea .
Viruses cannot multiply outside the living host cell, However the isolation, enumeration and identification become a difficult task. Instead of chemical medium they require a host body.
Viruses can be cultured in the animals such as mice ,monkeys, rabbits and guinea pigs etc. After inoculation animals are carefully examined for the development of signs or symptoms, further they may be killed.
SAP Unveils Generative AI Innovations at Annual Sapphire ConferenceCGB SOLUTIONS
At its annual SAP Sapphire conference, SAP introduced groundbreaking generative AI advancements and strategic partnerships, underscoring its commitment to revolutionizing business operations in the AI era. By integrating Business AI throughout its enterprise cloud portfolio, which supports the world's most critical processes, SAP is fostering a new wave of business insight and creativity.
This presentation intends to offer a bird's eye view of organic farming and its importance in the production of organic food and the soil health of artificial ecosystems.
Centrifugation is a technique, based upon the behaviour of particles in an applied centrifugal filed.
Centrifugation is a mechanical process which involves the use of the centrifugal force to separate particles from a solution according to their size, shape, density, medium viscosity and rotor speed.
The denser components of the mixture migrate away from the axis of the centrifuge, while the less dense components of the mixture migrate towards the axis.
precipitate (pellet) will travel quickly and fully to the bottom of the tube.
The remaining liquid that lies above the precipitate is called a supernatant.
Embracing Deep Variability For Reproducibility and Replicability
Abstract: Reproducibility (aka determinism in some cases) constitutes a fundamental aspect in various fields of computer science, such as floating-point computations in numerical analysis and simulation, concurrency models in parallelism, reproducible builds for third parties integration and packaging, and containerization for execution environments. These concepts, while pervasive across diverse concerns, often exhibit intricate inter-dependencies, making it challenging to achieve a comprehensive understanding. In this short and vision paper we delve into the application of software engineering techniques, specifically variability management, to systematically identify and explicit points of variability that may give rise to reproducibility issues (eg language, libraries, compiler, virtual machine, OS, environment variables, etc). The primary objectives are: i) gaining insights into the variability layers and their possible interactions, ii) capturing and documenting configurations for the sake of reproducibility, and iii) exploring diverse configurations to replicate, and hence validate and ensure the robustness of results. By adopting these methodologies, we aim to address the complexities associated with reproducibility and replicability in modern software systems and environments, facilitating a more comprehensive and nuanced perspective on these critical aspects.
https://hal.science/hal-04582287
Physics Investigatory Project on transformers. Class 12thpihuart12
Physics investigatory project on transformers with required details for 12thes. with index, theory, types of transformers (with relevant images), procedure, sources of error, aim n apparatus along with bibliography🗃️📜. Please try to add your own imagination rather than just copy paste... Hope you all guys friends n juniors' like it. peace out✌🏻✌🏻
TOPIC OF DISCUSSION: CENTRIFUGATION SLIDESHARE.pptxshubhijain836
Centrifugation is a powerful technique used in laboratories to separate components of a heterogeneous mixture based on their density. This process utilizes centrifugal force to rapidly spin samples, causing denser particles to migrate outward more quickly than lighter ones. As a result, distinct layers form within the sample tube, allowing for easy isolation and purification of target substances.
Discovery of Merging Twin Quasars at z=6.05Sérgio Sacani
We report the discovery of two quasars at a redshift of z = 6.05 in the process of merging. They were
serendipitously discovered from the deep multiband imaging data collected by the Hyper Suprime-Cam (HSC)
Subaru Strategic Program survey. The quasars, HSC J121503.42−014858.7 (C1) and HSC J121503.55−014859.3
(C2), both have luminous (>1043 erg s−1
) Lyα emission with a clear broad component (full width at half
maximum >1000 km s−1
). The rest-frame ultraviolet (UV) absolute magnitudes are M1450 = − 23.106 ± 0.017
(C1) and −22.662 ± 0.024 (C2). Our crude estimates of the black hole masses provide log 8.1 0. ( ) M M BH = 3
in both sources. The two quasars are separated by 12 kpc in projected proper distance, bridged by a structure in the
rest-UV light suggesting that they are undergoing a merger. This pair is one of the most distant merging quasars
reported to date, providing crucial insight into galaxy and black hole build-up in the hierarchical structure
formation scenario. A companion paper will present the gas and dust properties captured by Atacama Large
Millimeter/submillimeter Array observations, which provide additional evidence for and detailed measurements of
the merger, and also demonstrate that the two sources are not gravitationally lensed images of a single quasar.
Unified Astronomy Thesaurus concepts: Double quasars (406); Quasars (1319); Reionization (1383); High-redshift
galaxies (734); Active galactic nuclei (16); Galaxy mergers (608); Supermassive black holes (1663)
2. 2
Aggregates are inert
materials which are mixed
with binding material such as
cement or lime for
manufacturing of mortar or
concrete. Aggregates are
used as filler in mortar and
concrete and also to reduce
their cost.
5. USES OF AGGREGATES
• As an underlying material for foundations and
pavements
• As an ingredients in Portland cement concrete and
asphalt concrete.
6. SELECTION OF AGGREGATES
• aggregates shall be hard, durable and clean and free
from adherent coatings and organic matter and shall
not contain appreciable amount of clay.
• Aggregates shall not contain harmful impurities such as
iron pyrites, alkalis, salts, coal, mica, shale or other
materials which will affect hardening and attack
reinforcement.
7. CLASSIFICATION OF AGGREGATES
Based on size:
• classified into 2 categories:
• fine aggregates - those aggregates which pass through
4.75 mm sieve or aggregates with size less than 5 mm.
• Coarse aggregates – those aggregates
Passing through 75 mm sieve and entirely
retained on 4.75 mm sieve OR those
aggregates with size greater than 5 mm.
8. CLASSIFICATION OF AGGREGATES
Based on source or method of manufacture:
• classified into 2 categories:
• Natural aggregate/uncrushed aggregate- Those
from the river beds, river sand and ex-mines. Normally
rounded in shape and have smooth surface texture.
• Manufactured aggregate / crushed aggregate –those
obtained by mechanically crushing rocks, boulders, or
cobbles. Normally angular in shape and have rough
surface texture
9. CLASSIFICATION OF AGGREGATES
Based on Density:
• Based on specific gravity or density measured in
bulk, aggregate is divided into 3 types:
• Lightweight aggregate
• Normal-weight aggregate
• Heavyweight aggregate
10. NORMAL-WEIGHT AGGREGATE
• Crushed stone, gravel and ordinary sand are
examples of normal weight aggregate.
• They are commonly used in manufacture of
normal weight concrete, asphalt concrete
and roadway sub-base.
• The average values of sp.gr. For sand and
gravel are 2.6 and 2.65 respectively. Bulk
density of normal weight aggregate is around
1520 to 1680kg/m3.
11. LIGHTWEIGHT AGGREGATE
• Lightweight fine aggregate is any aggregate with
bulk density less than 1120kg/m3 and lightweight
coarse aggregate is any aggregate with bulk
density less than 880kg/m3.
• They are commonly used as ingredients in the
manufacture of lightweight concrete, for making
lightweight masonry blocks (to improved their
thermal and insulating properties and nailing
characteristic), and lightweight floor and roof slabs.
• 2 types of lightweight aggregate:
• Natural lightweight aggregates (eg: palm oil shell, rice husk,
etc)
• Manufactured (also called synthetic) lightweight
aggregates.
12. HEAVYWEIGHT AGGREGATE
• Those aggregate with high density and is used
primarily in the manufacture of heavyweight
concrete, employed for protection against nuclear
radiation and as bomb shelter.
• The unit weight of heavyweight concrete varies
from 2400kg/m3 with sp.gr range from 4.0 to 4.6.(eg:
mineral ores and barite)
14. STRENGTH OF AGGREGATES
• In practice, majority of normal aggregates are
considerably stronger than concrete
• A good average value of crushing strength of
aggregates is 200N/mm2.
15. HARDNESS OF AGGREGATES
• Hardness of aggregates is the ability of the
aggregate to withstand wear or load or
applied pressure.
• This hardness is depending on the type of
parent rock
• The test that can obtain the hardness is the
abrassion test.
• A satisfactory aggregate should have an
abrassion value of not more than 30% for
aggregates used for wearing surfaces and 50%
for aggregates used for non wearing surfaces.
16. TOUGHNESS
• Is the resistance of aggregate to failure by
impact.
• This can be determined by aggregate impact
test.
• The aggregate impact value shall not exceed
45% by weight for aggregate used for
concrete other than those used for wearing
surfaces and 30% for concrete for wearing
surfaces.
17. DURABILITY OF AGGREGATES
• Durability is ability of the aggregate to withstand
external or internal damaging attack or in other
words the soundness of aggregate.
• This can be obtained by carrying out the Soundness
test.
18. POROSITY
• Aggregate normally have pores of various
sizes.
• Aggregates will absorb water when it is dry
but normally release water in the concrete
mix when it is wet.
• The amount of water and its rate of
permeation depends on the size and volume
of aggregate
• Since the aggregate comprises 75% of the
concrete volume, it is essential to note that
porosity of an aggregate contribute to the
overall porosity of concrete.
19. TESTS ON AGGREGATES
a.Texture and shapes test
i.e. test for shapes of aggregates:
1. round shape –usually natural aggregates
2. irregular shape- a combination of different shapes
3. angular shape- usually of crushed stone
4. flaky shape- where the thickness is less than its length and
width
5. elongated- usually angular where its length is larger than
its width and thickness
6. flaky and elongated- its length is larger than its width and
its width is larger than its thickness.
• In terms of surface texture, the aggregates may have a
smooth texture, or coarse/rough texture or fissures or
porous.
• For production of concrete the aggregates which have
angular shape and coarse texture are recommended to
have high bond strength.
20. TESTS ON AGGREGATES (CONT’D)
• Strength tests
• Aggregates crushing strength
• Los Angeles abrasion test
• Aggregates Impact value test
• Ten percent fine test
21. TESTS ON AGGREGATES (CONT’D)
Physical properties:
• Specific gravity: usually 2.6 or 2.7
• Water absorption test: aggregates absorb water
because of their porosity.
• If all the pores are filled with water the
aggregates are said to be saturated and
surface dry.
• If all the water inside the pores are
removed by drying, the aggregates are
said to have maximum dry weight.
22. GRADING OF AGGREGATES:
• Coarse and fine aggregates to be used for
making concrete should be well graded.
Gradation means the particle size distribution of
aggregates. Test for grading of aggregates is
carried out using the sieve analysis method.
24. EXAMPLE OF SIEVE ANALYSIS OF
SAND
Sieve Mass Cumulative Mass %
Size retained mass retained passing passing
10 mm 0 0 287 100
5 mm 6 6 281 98
2.36 mm 17 23 264 92
1.18 mm 32 55 232 81
600mm 48 103 184 64
300mm 81 184 103 36
150mm 86 270 17 6
Pan 17 287 - -
287
25. A SIEVE ANALYSIS OF 250G OF SAND GIVES
THE
FOLLOWING RESULTS
Sieve size Mass retained
10 mm 0
5 mm 5
2.36 mm 31
1.18 mm 38
600mm 38
300mm 79
150m 51
Pan 8
26. M.S. 30- Typical grading of fine aggregates
% passing by weight
B.S. 410 Zone 2 Zone 3
Test Sieve
------------------------------------------------------
10.0 mm 100 100
5.0 90-100 90-100
2.36 75-100 85-100
1.18 55-90 75-100
600m 35-59 60-79
300m 8-30 12-40
150m 0-10 0-10
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37. To calculate moisture content of Aggregates
Example:
A sample of damp aggregate weighing 2.35 kg is
dried by hair dryer until it just reaches the free-
running(saturated surface dry) condition. It is
then found to weigh 2.24 kg. After drying in the
oven at 110C to constant mass, it is found to
weigh 2.15 kg. Based on dry mass, calculate:
•free-water content
•the total water content
38. Solution:
a) Free-water content in aggregate is defined as the water content
when the aggregate is in saturated surface dry conditions.
i.e. initial weight = 2.35 kg
weight at SSD = 2.24 kg
free water content = 0.11 kg
% of free-water content based on dry mass
= 0.11/2.15 x 100 = 5.1%
b) Total water content = free-water content
+
water absorbed by aggregates
= 0.11 + (2.24 – 2.15)
= 0.2 kg
OR 2.35 – 2.15 = 0.2 kg
(i.e overall weight - wt of max. dry aggregates)
% of total water content based on dry mass,
= 0.2/2.15 x 100
= 9.3%
48. DEPENDING UPON THE SIZE
OF THEIR PARTICLES
AGGREGATES ARE
CLASSIFIED AS:
(1) FINE AGGREGATES
(2) COARSE AGGREGATES
49. (1) FINE AGGREGATES:
Aggregates whose particles pass through 4.75 mm IS
sieve are termed as fine aggregates. Most commonly
used fine aggregates are sand (pit or quarry sand,
river sand and sea sand) and crushed stone in
powdered form, how ever some times sukhi and ash
or cinder are also used.
Jyoti Anischit 49
50. (A) SAND:
It consists of small angular or rounded grains of
silica depending upon the source from which
it is obtained. It is classified as:
50
51. (I) PIT OR QUARRY SAND:
It is found as deposited in soil and is to
be excavated out. Its grains are
generally sharp or angular. It should be
free from organic matter and clay. It is
usually considered to be the best fine
aggregate for use in mortar and
concrete.
51
52. (II) RIVER SAND:
IT IS OBTAINED FROM THE BANKS
AND BEDS OF RIVERS. IT MAY BE
FINE OR COARSE. FINE SAND
OBTAINED FROM BEDS AND BANKS
OF RIVERS IS OFTEN FOUND MIXED
WITH SILT AND CLAY SO IT
SHOULD BE WASHED BEFORE USE.
BUT COARSE SAND IS GENERALLY
CLEAN AND EXCELLENT FOR USE
ESPECIALLY FOR PLASTERING.
52
53. (iii) Sea Sand:
It consists of fine rounded grains of brown
colour and it is collected from sea shores or
sea beaches. Sea sand usually contains salts
and while using that in mortar, etc, causes
disintegration of the work in which it is used. In
R.C.C work these salts will attack
reinforcement if salt content is high. These salts
may cause efflorescence. It should be used
locally after thorough washing.
53
54. (b) Crushed stone:
It is obtained by crushing the waste stones of
quarries to the particular size of sand. Sand
obtained from by crushing a good quality
stone is excellent fine aggregate.
Mortar made with this sand is usually used in
ashlar work (good quality of work).
54
55. (2) COARSE AGGREGATES:
Aggregates whose particles
do not pass through 4.75 mm
IS are termed as coarse
aggregates. Most commonly
used coarse aggregates are
crushed stone, gravel; broken
pieces of burnt bricks,etc.
55
56. (A) CRUSHED STONE:
It is an excellent coarse aggregate and is
obtained by crushing granite, sand stone or
grained lime stone and all types of stones.
Crushed stones are used for the
construction of roads and railway tracks,
etc.
56
57. (b) Gravel:
It is an other very good coarse
aggregate. It is obtained from
river beds, quarries and sea
shores. The gravel obtained
from sea shores should be well
washed with fresh water
before use in order to remove
the impurities which may be
clay, salts ,silt,etc. It is
commonly used in the
preparation of concrete.
57
58. (c) Broken pieces of bricks:
It is also a good artificial source of
coarse aggregates. It is obtained by
breaking well burnt bricks. It is generally
used in lime concrete at places where
aggregates from natural sources are
either not available or are expensive. It
can be used at places where low
strength is required. It should be
watered well before using it in the
preparation of concrete. It is
commonly used for mass concrete in
foundations and under floors.
58
59. GOOD QUALITYIES OF AN IDEAL AGGREGATE:
An ideal aggregate used for the
manufacturing of concrete and mortar,
should meet the following requirements.
• (1) It should consist of natural stones, gravels
and sand or in various combinations of these
materials.
• (2) It should be hard, strong and durable.
59
60. • (3) It should be dense, clear and free from
any coating.
• (4) It should be free from injurious vegetable
matters.
• (5) It should not contain flaky (angular) and
elongated pieces.
• (6) It should not contain any material liable
to attack steel reinforcement in case of
reinforced concrete.
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62. 1.COMPOSITION:
• Aggregate containing the constituents
which generally react with alkalies in
cement cause excessive expansion,
cracking of concrete mix, should never be
used. Suitability of aggregates should be
judged either by studying its service history
or by laboratory tests.
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63. 2. SIZE AND SHAPE:
The size and shape of the aggregate
particles mainly influence the quantity of
cement required in a concrete mix and
ultimately economy of the concrete. For the
preparation of economical concrete, one
should use largest coarse aggregates
feasible for the structure.
63
64. Type of structure Max. size of aggregate
1. Mass concrete work 40 mm
i.e. dams, retaining walls,
piers and abutments, etc.
2. R.C.C work 20 mm
i.e. beams, columns, etc
3. Flooring 10 mm
It may be clearly noted that the size and
shape of the aggregate particles influence
the properties of freshly mixed concrete more
as compared to those of hardened concrete.
64
65. QUALITY TESTS OF
AGGREGATES:
There are so many tests which are to be
performed to check the quality of
aggregates but some important tests are
discussed below.
65
66. 1. CRUSHING TEST OF AGGREGATE:
The aggregate crushing value gives a
relative measure of resistance of an
aggregate to crushing under a gradually
applied compressive load. The aggregate
crushing strength value is useful factor to
know the behaviour of aggregates when
subjected to wear.
66
67. 2. IMPACT VALUE TEST:
The aggregate impact value gives a
relative measure of the resistance of an
aggregate to sudden shock or impact. The
impact value is some times used as an
alternative to its crushing value.
67
68. 3. ABRASION VALUE:
The aggregate abrasion
value gives a relative
measure of resistance of
an aggregate to wear
when it is rotated in a
cylinder along with some
abrasive charge.
68
69. SIEVE ANALYSIS:
In determination of the proportions of the
particles with in certain ranges in an
aggregate by separation on various sieves
of different size openings, may be defined
as sieve analysis.
69
70. FINENESS MODULUS (F.M):
The sum of cumulative percentage of
residues retained on each of the Indian
standard sieves
(80mm,40mm,20mm,10mm,4.75mm,2.36
mm,1.18mm,600 microns,300microns
and 150 microns each succeeding
sieve has half the aperture of the
previous one), divided by the 100,is
known as “Fineness modulus” of the
aggregates. The fineness modulus of an
aggregate is roughly proportional to the
average size of particles of the
aggregates.
70
71. (OR)
Index Number expressing the relative
sizes of both coarse and fine
aggregates is called “Fineness
Modulus”.
Sand Fineness Modulus
• Fine 2.2 to 2.6
• Medium 2.6 to 2.9
• Coarse 2.9 to 3.2
Note:
It is recommended that the fineness
modulus of sand should not be less
than 2.5 and should not be more than
3.0
71
72. STONE MASONRY
• The construction of stones bonded together with
mortar is termed as stone masonry where the
stones are available in a abundance in nature,
on cutting and dressing to the proper shape,
they provide an economical material for the
construction of various building components
such as walls, columns, footings, arches, lintels,
beams etc.
73. USES
1) Building foundations, walls, piers, pillars, and
architectural works.
2) Lintels, Beams, beams Arches, domes etc.,
3) Roofs and Roof coverings.
4) Cladding Works
5) Dams, light houses, monumental structures.
6) Paving jobs
7) Railway, ballast, black boards and electrical switch
74. SELECTION OF STONE FOR STONE
MASONRY:
1) Availability
2) Ease of working
3) Appearance
4) Strength and stability
5) Polishing characteristics
6) Economy
7) Durability
78. GENERAL PRINCIPLES
• The stones to be used for stone masonry should
be hard, tough and durable.
• The pressure acting on stones should be vertical.
• The stones should be perfectly dressed as per
the requirements.
• The heads and bond stones should not be of a
dumb bell shape.
• In order to obtain uniform distribution of load,
under the ends of girders, roof trusses etc large
flat stones should be used
79. GENERAL PRINCIPLES
• The mortar to be used should be good quality
and in the specified faces.
• The construction work of stone masonry should
be raised uniformly.
• The plumb bob should be used to check the
verticality of erected wall.
• The stone masonry section should always be
designed to take compression and not the
tensile stresses.
• The masonry work should be properly cured after
the completion of work, for a period of 2 to 3
weeks.
80. • As far as possible broken stones or small stones
chips should not be used.
• Double scaffolding should be used for working at
higher level.
• The masonry hearting should be properly
packed with mortar and chips if necessary to
avoid hallows.
• The properly wetted stones should be used to
avoid mortar moisture being sucked.
General Principles
81. LAYING THE STONE
• Decrease the stone thickness from the bottom to the
top of wall.
• Ensure that the headers in the heart of the wall are
the same size as in the face and extend at least 12 in
(300 mm) into the core or backing. (Avoid Dumb-
bell shaped stones)
• Ensure that headers in “walls of 2 feet (600 mm) or
less in thickness” extend entirely through the wall. The
headers shall occupy at least 20 percent of the face
of the wall.
82. • Lay the masonry in roughly leveled courses. Ensure that the
bottom of the foundation is large, with selected stones.
• Lay the courses with leaning beds parallel to the natural bed
of the material.
• Regularly diminish the thicknesses of the courses, if varied, from
the bottom to the top of the wall. Keep a surplus supply of
stones at the site to select from.
• Before laying the stone in the wall, shape and dress it so that it
will not loosen after it is placed. No dressing or hammering
which will loosen the stone will be permitted after it is placed.
Laying The Stone
83. • Clean each stone and saturate it with water
before setting it. Clean and moisten the bed
that will receive it.
• Bed the stones in freshly made mortar with full
joints. Carefully settle the stones in place before
the mortar sets.
• Ensure that the joints and beds have an average
thickness of not more than 1 inch. (25 mm).
• Ensure that the vertical joints in each course
break with the adjoining courses at least 6 in.
(150 mm).
84. • If a stone is moved or if the joint is broken after
the mortar has set, take the stone up and
thoroughly clean the mortar from the bed and
joints. Reset the stone in fresh mortar.
• NOTE: Do not lay the masonry in freezing weather
or when the stone contains frost, except with
permission subjected to the required conditions.
• Whenever possible, properly point the face joints
before the mortar sets. If joints cannot be
pointed, rake them out to a depth of 1 in (25
mm) before the mortar sets.
• Do not smear the stone face surfaces with the
mortar forced out of the joints or the mortar used
85. • Thoroughly wet the joints pointed after the stone is
laid with clean water and fill with mortar.
• Drive the mortar into the joints and finish with an
approved pointing tool.
• Keep the wall wet while pointing. In hot or dry
weather, protect the pointed masonry from the sun
and keep it wet for at least three days after the
pointing is finished.
• NOTE: Do not perform pointing in freezing weather or
when the stone contains frost.
• After the pointing is completed and the mortar is set,
thoroughly clean the walls and leave them in a neat
condition.
86.
87. Stone
a natural, hard substance formed from
minerals and earth material which are
present in rocks.
Rock
the portion of the earth’s crust having no
definite shape and structure
88. To qualify as a construction material, stone
should have the following qualities:
89. Strength: Most types of
stone have more than
adequate compressive
strength. The shear
strength of stone,
however, is usually
about 1/10 of its
compressive strength
91. Hardness:
Talc, easily scratched with the thumb-nail: 1
Gypsum, scratched by the thumb-nail: 2
Calcite, not scratched by thumb-nail but easily cut by knife: 3
Fluorite, can be cut by knife with greater difficulty than calcite: 4
Apatite, can be cut only with difficulty by knife: 5
Orthoclase, can be cut w/ knife w/ great difficulty on thin edges: 6
Quartz, not scratched by steel, scratches glass: 7
Topaz: 8
Sapphire: 9
Diamond: 10
92. Durability: Resistance
to the weathering
effects of rain, wind,
heat, and frost action
is necessary for
exterior stonework
100. Metamorphic rocks has undergone a change
in structure, texture, or composition due to
the natural agencies, as heat and pressure,
especially when the rock becomes harder
and more crystalline, as marble and slate
104. As a load bearing wall material, stone is
similar to modular unit masonry. Although
stone masonry is not necessarily uniform in
size, its laid up with mortar and used in
compression. Almost all stone is adversely
affected by sudden changes in temperature
and should not be used where a high degree
of fire resistance is required.
105. Stone is used in construction in the following
forms:
• Rubble
• Dimension stone
• Flagstone
• Crushed stone
106. Rubble - consists of rough fragments of broken
stone that have at least one good face for
exposure in a wall.
107. Dimension stone - is quarried and squared stone
2’ or more in length and width and of specified
thickness, used commonly for wall panels,
cornices, copings, lintels and flooring.
108. Flagstone - refers to flat stone slabs used for
flooring and horizontal surfacing.
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