It is the presentation based on precast concrete construction which includes each and every point and scope which may be useful to civil engineering students
This document discusses prefabrication in construction. Prefabrication involves assembling structural components at a factory or manufacturing site and transporting them to the construction site for assembly. It describes the advantages as less noise, dust, time and costs compared to on-site construction. Potential disadvantages include transportation costs, accuracy needs and reduced aesthetic variety. The document outlines various prefabrication components, materials, systems, joints, casting methods and the differences between on-site and off-site prefabrication.
The document discusses precast concrete construction. Some key points:
- Precast concrete components are cast off-site in a controlled environment and transported to the construction site for assembly. This allows for standardized, mass produced elements.
- Large precast concrete panels form the walls and floors, connecting vertically and horizontally. When joined, they form a rigid box structure that transfers lateral loads.
- Connections between precast elements can be either dry joints using bolts/welds, or monolithic placement with concrete poured to join components.
This document discusses prefabrication in construction. Prefabrication involves assembling components of a structure in a factory then transporting them to the construction site. It has advantages like reduced cost, time, and waste and allows work during poor weather. Common prefabricated components include columns, beams, waffle floors/roofs which are cast and cured off-site then erected using cranes. While prefabrication offers benefits, it also has disadvantages like potential breakage during transport and need for specialized equipment and labor. The document concludes that partial prefabrication is well-suited for Indian conditions.
Shoring is the construction of a temporary structure to support an unsafe or unstable structure. There are three main types of shoring: raking shores, flying shores, and dead shores. Raking shores use inclined members called rakers to provide lateral support to walls. Flying shores provide temporary support between party walls when an intermediate building is demolished. Dead shores provide vertical support to walls and structures when the lower part of a wall is removed, such as to add an opening.
It is used as a mould for a structure in which fresh concrete is poured only to harden subsequently.
formwork for concrete slab
beam formwork
steel formwork
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types of formwork
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what is formwork in construction
building formwork
plywood disadvantages
advantage plywood
advantages and disadvantages of wood
best plywood for formwork
plywood formwork for concrete
mdf advantages and disadvantages
examples of advantages and disadvantages
advantage steel and construction
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1) High rise buildings are becoming more common due to scarcity of land and demand for space. They are defined differently but generally refer to buildings over 15 meters tall.
2) Foundations for high rise buildings include shallow foundations like spread footings and mat foundations, and deep foundations like piles. Piles transfer load through end bearing or friction along their length.
3) Structural systems for high rise buildings must resist both gravity and lateral loads. Interior systems include rigid frames and shear walls. Exterior systems such as tube and diagrid systems resist loads along the building perimeter.
This document discusses prefabricated modular structures. Some key points:
1. Prefabricated structures have standardized components that are produced off-site in a controlled environment and then transported for assembly. This allows for faster, more efficient construction.
2. Precast concrete offers advantages like higher quality, less weather dependency, and unlimited design possibilities compared to site-cast construction.
3. There are different precast systems like large panel, frame, and lift-slab. Precast components include walls, floors, beams, and more.
This document discusses prefabrication in construction. Prefabrication involves assembling structural components at a factory or manufacturing site and transporting them to the construction site for assembly. It describes the advantages as less noise, dust, time and costs compared to on-site construction. Potential disadvantages include transportation costs, accuracy needs and reduced aesthetic variety. The document outlines various prefabrication components, materials, systems, joints, casting methods and the differences between on-site and off-site prefabrication.
The document discusses precast concrete construction. Some key points:
- Precast concrete components are cast off-site in a controlled environment and transported to the construction site for assembly. This allows for standardized, mass produced elements.
- Large precast concrete panels form the walls and floors, connecting vertically and horizontally. When joined, they form a rigid box structure that transfers lateral loads.
- Connections between precast elements can be either dry joints using bolts/welds, or monolithic placement with concrete poured to join components.
This document discusses prefabrication in construction. Prefabrication involves assembling components of a structure in a factory then transporting them to the construction site. It has advantages like reduced cost, time, and waste and allows work during poor weather. Common prefabricated components include columns, beams, waffle floors/roofs which are cast and cured off-site then erected using cranes. While prefabrication offers benefits, it also has disadvantages like potential breakage during transport and need for specialized equipment and labor. The document concludes that partial prefabrication is well-suited for Indian conditions.
Shoring is the construction of a temporary structure to support an unsafe or unstable structure. There are three main types of shoring: raking shores, flying shores, and dead shores. Raking shores use inclined members called rakers to provide lateral support to walls. Flying shores provide temporary support between party walls when an intermediate building is demolished. Dead shores provide vertical support to walls and structures when the lower part of a wall is removed, such as to add an opening.
It is used as a mould for a structure in which fresh concrete is poured only to harden subsequently.
formwork for concrete slab
beam formwork
steel formwork
doka h20
types of formwork
formwork for concrete
what is formwork in construction
building formwork
plywood disadvantages
advantage plywood
advantages and disadvantages of wood
best plywood for formwork
plywood formwork for concrete
mdf advantages and disadvantages
examples of advantages and disadvantages
advantage steel and construction
advantages of steel
disadvantages of steel structures
examples of advantages and disadvantages
advantages and disadvantages of surveys
wiki advantages and disadvantages
steel formwork design
steel formwork system
1) High rise buildings are becoming more common due to scarcity of land and demand for space. They are defined differently but generally refer to buildings over 15 meters tall.
2) Foundations for high rise buildings include shallow foundations like spread footings and mat foundations, and deep foundations like piles. Piles transfer load through end bearing or friction along their length.
3) Structural systems for high rise buildings must resist both gravity and lateral loads. Interior systems include rigid frames and shear walls. Exterior systems such as tube and diagrid systems resist loads along the building perimeter.
This document discusses prefabricated modular structures. Some key points:
1. Prefabricated structures have standardized components that are produced off-site in a controlled environment and then transported for assembly. This allows for faster, more efficient construction.
2. Precast concrete offers advantages like higher quality, less weather dependency, and unlimited design possibilities compared to site-cast construction.
3. There are different precast systems like large panel, frame, and lift-slab. Precast components include walls, floors, beams, and more.
This document discusses column jacketing, which is a method of retrofitting and strengthening existing columns. It involves adding reinforced concrete, steel, or fiber-reinforced polymer around the column. The key steps are preparing the column surface, adding shear keys and reinforcement, applying a bonding agent, and casting the new concrete or installing the jacket. Column jacketing increases the strength and seismic capacity of the column. It improves confinement and increases axial, shear, and foundation load capacity without significant weight addition.
Prefabrication is the practice of assembling components of a structure in a factory or other manufacturing site, and transporting them to the construction site where the structure is to be located.
Prefabrication involves assembling building components in a factory and transporting them to the construction site. There are several prefabrication systems including open prefab, box type, and large prefab. Prefabricated components include panels, roofs, floors, and more which are manufactured off-site and assembled on-site. Prefabrication offers benefits like reduced construction time and costs, improved quality, and less waste. However, it also has disadvantages such as requiring specialized equipment and skilled labor for transportation and assembly. A case study on a housing project in India demonstrated how prefabrication helped complete buildings faster and with higher quality.
The document discusses common defects found in buildings such as cracks and dampness. It categorizes defects into pre-construction, during construction, and post-construction. Cracks can be structural or non-structural, and are caused by factors like drying shrinkage, thermal movement, elastic deformation, creep, chemical reactions, and foundation issues. Dampness is usually due to penetrating damp from gaps or rising damp without a proper damp proof course. Preventive measures include proper design, materials, construction practices, and addressing the root causes of defects.
This document discusses prefabricated concrete columns. It defines prefabrication as assembling building components in a factory and transporting them to the construction site. Precast concrete columns can be single or double-story height and are made in modular designs to accommodate different heights. Columns have widths of 300mm, 450mm, or 600mm and can be rectangular or circular. Connection methods between the column and foundation include cast-in base plates, dowel tubes, or projections. The manufacturing process for precast concrete components involves 10 main steps including installing molds and reinforcement, pouring and vibrating concrete, curing, and removing molds.
This document discusses different methods of prestressing concrete, including pretensioning and post-tensioning. Pretensioning involves stressing steel tendons before placing concrete around them, while post-tensioning involves stressing tendons after the concrete has cured using hydraulic jacks. Post-tensioning allows for longer spans, thinner slabs, and more architectural freedom compared to conventional reinforced concrete or pretensioned concrete. Common applications of post-tensioning include parking structures, bridges, and building floors and roofs.
Precast concrete construction involves casting concrete structural elements at a manufacturing facility rather than on site. This allows for rapid construction, high quality control, and easy incorporation of prestressing. Precast concrete provides advantages like speed of erection, durability, and economy, but also has disadvantages such as weight, limited flexibility in design, and need for skilled workmanship and lifting equipment on site. Common precast concrete elements include walls, slabs, beams, and structural framing using techniques like welded plates and rebar splicing.
Trusses are commonly used in buildings to span long distances and carry heavy loads. Steel trusses are preferred over wood trusses for their strength, simplicity of installation, and durability without risk of rotting. Various types of trusses include king post, queen post, Howe, Pratt, and fan trusses used in roofs, as well as north light trusses traditionally used for industrial buildings to maximize natural lighting. Larger spans may use tubular steel, quadrangular, or gusset plate connected trusses, while galvanized steel sheets are often used for roofing material.
This document provides information on industrial buildings, including their components and factors to consider in design. Key points include:
- Industrial buildings are used for manufacturing and storage by industries and include steel plants, warehouses, and factories.
- Site selection considers access, raw materials, utilities, land characteristics, and transportation.
- Major components include the roof, trusses, purlins, girts, bracing, and foundations.
- Design considerations cover roofing/wall materials, bay widths, structural framing, truss configurations, and bracing to resist lateral loads.
This document discusses precast concrete construction. Some key points:
- Precast concrete elements are cast and cured off-site then transported for assembly, allowing more efficient production and quality control.
- Elements include slabs, beams, columns, and wall panels that are joined on-site through embedded bolts, plates, and grouted connections.
- The precasting process involves casting concrete around prestressing strands to add strength, then cutting sections and transporting them for erection.
Prefabrication types and Applications explainedEyad Reda
Explaining prefabrication in construction in a simple way. The contents range from steel framing, Precast concrete, Concrete prefab systems, sandwich paneling, timber framing and Real-life applications for prefabrication.
This lecture discusses precast concrete construction. It differentiates between architectural and structural precast concrete. Total precast construction uses only precast concrete for all building elements, while mixed precast combines precast with other materials. Joints and connections between precast elements are crucial and include slab to slab, slab to beam, and column to column connections. The construction process for precast buildings is similar to steel construction, with elements connected by welding or bolting after being lifted into place by crane.
This document provides details on the design and construction of flat slab structures. It discusses the benefits of flat slabs such as flexibility in layout, reduced building height and faster construction. Key considerations for design include wall and column placement, structural layout optimization, deflection checks, crack control and punching shear. Analysis involves dividing the slab into strips and determining moment and shear distributions. Reinforcement is arranged in two directions and detailing includes reinforcement lapping and service penetrations.
Modular coordination is a concept of coordination of dimension and space, in which buildings and components are dimensioned and positioned in a term of a basic unit or module, known as ‘1M’ which is equivalent to 100 mm.
Bc open pre fabricated construction systemAnuj Singhal
The document discusses an open prefabricated construction system. Some key points:
- Prefabrication involves assembling building components in a factory and transporting them to the construction site. This speeds up construction time and lowers costs while ensuring quality.
- An open prefabricated system uses precast concrete or steel components like floors, walls, beams and columns assembled on-site. It can be partially or fully prefabricated.
- Examples of full prefabricated open systems include the Nakagin Capsule Tower in Tokyo, with prefabricated steel living capsules bolted to a central concrete core. Prefabrication allowed efficient off-site assembly and construction.
Flat slabs are reinforced concrete slabs that are supported directly by columns without beams. They provide minimum depth, fast construction, and flexible column placement. There are four main types: slabs without drops and with column heads, slabs with drops and without column heads, slabs with both drops and column heads, and typical flat slabs. Column heads increase shear strength while drops increase shear strength and negative moment capacity. Flat slab systems can be either one-way or two-way depending on span ratios and load distribution. Advantages include simple formwork, no beams, and minimum depth, while disadvantages include potential interference from drops.
Slip form construction is a method where concrete is poured into a continuously moving form to construct structures without joints. There are two main types - vertical slip forming used for tall structures like buildings and towers, and horizontal slip forming for pavement. The moving formwork is supported by hydraulic jacks and remains intact until the entire structure is completed, allowing faster construction at lower cost compared to traditional formwork. Slip forming produces monolithic, jointless structures but requires careful planning of the construction process and a skilled workforce.
Pre-stressed concrete uses tensioned steel strands or bars to place concrete in compression before application of service loads. This counters the tensile stresses induced by loads and prevents cracking. There are two main methods: pre-tensioning applies tension before pouring concrete, while post-tensioning tensions strands after concrete curing. Pre-stressed concrete allows for smaller and lighter structures that resist loads, deflection, and cracking better than reinforced concrete.
This document provides guidelines for the design of highway pavements in India. It discusses different types of pavements, including flexible and rigid pavements. For rigid pavement design, it outlines factors like traffic, climate, materials properties. It describes the components and types of joints in concrete roads. For flexible pavement design, it discusses the group index and CBR methods, which consider soil properties and traffic volumes to determine layer thicknesses. The document provides details on mix design methods for bituminous concrete like Marshall and Hveem.
Concrete is a composite material made of aggregates, sand, cement and water. It has many useful properties such as versatility, durability and fire resistance which make it widely used in construction. Fresh concrete must have adequate workability and consistency to be properly mixed, placed and consolidated. Proper curing is also important to allow the cement to fully hydrate and gain strength over time. While concrete has advantages, it also has disadvantages like low tensile strength and requires careful mixing to ensure uniformity.
This document discusses column jacketing, which is a method of retrofitting and strengthening existing columns. It involves adding reinforced concrete, steel, or fiber-reinforced polymer around the column. The key steps are preparing the column surface, adding shear keys and reinforcement, applying a bonding agent, and casting the new concrete or installing the jacket. Column jacketing increases the strength and seismic capacity of the column. It improves confinement and increases axial, shear, and foundation load capacity without significant weight addition.
Prefabrication is the practice of assembling components of a structure in a factory or other manufacturing site, and transporting them to the construction site where the structure is to be located.
Prefabrication involves assembling building components in a factory and transporting them to the construction site. There are several prefabrication systems including open prefab, box type, and large prefab. Prefabricated components include panels, roofs, floors, and more which are manufactured off-site and assembled on-site. Prefabrication offers benefits like reduced construction time and costs, improved quality, and less waste. However, it also has disadvantages such as requiring specialized equipment and skilled labor for transportation and assembly. A case study on a housing project in India demonstrated how prefabrication helped complete buildings faster and with higher quality.
The document discusses common defects found in buildings such as cracks and dampness. It categorizes defects into pre-construction, during construction, and post-construction. Cracks can be structural or non-structural, and are caused by factors like drying shrinkage, thermal movement, elastic deformation, creep, chemical reactions, and foundation issues. Dampness is usually due to penetrating damp from gaps or rising damp without a proper damp proof course. Preventive measures include proper design, materials, construction practices, and addressing the root causes of defects.
This document discusses prefabricated concrete columns. It defines prefabrication as assembling building components in a factory and transporting them to the construction site. Precast concrete columns can be single or double-story height and are made in modular designs to accommodate different heights. Columns have widths of 300mm, 450mm, or 600mm and can be rectangular or circular. Connection methods between the column and foundation include cast-in base plates, dowel tubes, or projections. The manufacturing process for precast concrete components involves 10 main steps including installing molds and reinforcement, pouring and vibrating concrete, curing, and removing molds.
This document discusses different methods of prestressing concrete, including pretensioning and post-tensioning. Pretensioning involves stressing steel tendons before placing concrete around them, while post-tensioning involves stressing tendons after the concrete has cured using hydraulic jacks. Post-tensioning allows for longer spans, thinner slabs, and more architectural freedom compared to conventional reinforced concrete or pretensioned concrete. Common applications of post-tensioning include parking structures, bridges, and building floors and roofs.
Precast concrete construction involves casting concrete structural elements at a manufacturing facility rather than on site. This allows for rapid construction, high quality control, and easy incorporation of prestressing. Precast concrete provides advantages like speed of erection, durability, and economy, but also has disadvantages such as weight, limited flexibility in design, and need for skilled workmanship and lifting equipment on site. Common precast concrete elements include walls, slabs, beams, and structural framing using techniques like welded plates and rebar splicing.
Trusses are commonly used in buildings to span long distances and carry heavy loads. Steel trusses are preferred over wood trusses for their strength, simplicity of installation, and durability without risk of rotting. Various types of trusses include king post, queen post, Howe, Pratt, and fan trusses used in roofs, as well as north light trusses traditionally used for industrial buildings to maximize natural lighting. Larger spans may use tubular steel, quadrangular, or gusset plate connected trusses, while galvanized steel sheets are often used for roofing material.
This document provides information on industrial buildings, including their components and factors to consider in design. Key points include:
- Industrial buildings are used for manufacturing and storage by industries and include steel plants, warehouses, and factories.
- Site selection considers access, raw materials, utilities, land characteristics, and transportation.
- Major components include the roof, trusses, purlins, girts, bracing, and foundations.
- Design considerations cover roofing/wall materials, bay widths, structural framing, truss configurations, and bracing to resist lateral loads.
This document discusses precast concrete construction. Some key points:
- Precast concrete elements are cast and cured off-site then transported for assembly, allowing more efficient production and quality control.
- Elements include slabs, beams, columns, and wall panels that are joined on-site through embedded bolts, plates, and grouted connections.
- The precasting process involves casting concrete around prestressing strands to add strength, then cutting sections and transporting them for erection.
Prefabrication types and Applications explainedEyad Reda
Explaining prefabrication in construction in a simple way. The contents range from steel framing, Precast concrete, Concrete prefab systems, sandwich paneling, timber framing and Real-life applications for prefabrication.
This lecture discusses precast concrete construction. It differentiates between architectural and structural precast concrete. Total precast construction uses only precast concrete for all building elements, while mixed precast combines precast with other materials. Joints and connections between precast elements are crucial and include slab to slab, slab to beam, and column to column connections. The construction process for precast buildings is similar to steel construction, with elements connected by welding or bolting after being lifted into place by crane.
This document provides details on the design and construction of flat slab structures. It discusses the benefits of flat slabs such as flexibility in layout, reduced building height and faster construction. Key considerations for design include wall and column placement, structural layout optimization, deflection checks, crack control and punching shear. Analysis involves dividing the slab into strips and determining moment and shear distributions. Reinforcement is arranged in two directions and detailing includes reinforcement lapping and service penetrations.
Modular coordination is a concept of coordination of dimension and space, in which buildings and components are dimensioned and positioned in a term of a basic unit or module, known as ‘1M’ which is equivalent to 100 mm.
Bc open pre fabricated construction systemAnuj Singhal
The document discusses an open prefabricated construction system. Some key points:
- Prefabrication involves assembling building components in a factory and transporting them to the construction site. This speeds up construction time and lowers costs while ensuring quality.
- An open prefabricated system uses precast concrete or steel components like floors, walls, beams and columns assembled on-site. It can be partially or fully prefabricated.
- Examples of full prefabricated open systems include the Nakagin Capsule Tower in Tokyo, with prefabricated steel living capsules bolted to a central concrete core. Prefabrication allowed efficient off-site assembly and construction.
Flat slabs are reinforced concrete slabs that are supported directly by columns without beams. They provide minimum depth, fast construction, and flexible column placement. There are four main types: slabs without drops and with column heads, slabs with drops and without column heads, slabs with both drops and column heads, and typical flat slabs. Column heads increase shear strength while drops increase shear strength and negative moment capacity. Flat slab systems can be either one-way or two-way depending on span ratios and load distribution. Advantages include simple formwork, no beams, and minimum depth, while disadvantages include potential interference from drops.
Slip form construction is a method where concrete is poured into a continuously moving form to construct structures without joints. There are two main types - vertical slip forming used for tall structures like buildings and towers, and horizontal slip forming for pavement. The moving formwork is supported by hydraulic jacks and remains intact until the entire structure is completed, allowing faster construction at lower cost compared to traditional formwork. Slip forming produces monolithic, jointless structures but requires careful planning of the construction process and a skilled workforce.
Pre-stressed concrete uses tensioned steel strands or bars to place concrete in compression before application of service loads. This counters the tensile stresses induced by loads and prevents cracking. There are two main methods: pre-tensioning applies tension before pouring concrete, while post-tensioning tensions strands after concrete curing. Pre-stressed concrete allows for smaller and lighter structures that resist loads, deflection, and cracking better than reinforced concrete.
This document provides guidelines for the design of highway pavements in India. It discusses different types of pavements, including flexible and rigid pavements. For rigid pavement design, it outlines factors like traffic, climate, materials properties. It describes the components and types of joints in concrete roads. For flexible pavement design, it discusses the group index and CBR methods, which consider soil properties and traffic volumes to determine layer thicknesses. The document provides details on mix design methods for bituminous concrete like Marshall and Hveem.
Concrete is a composite material made of aggregates, sand, cement and water. It has many useful properties such as versatility, durability and fire resistance which make it widely used in construction. Fresh concrete must have adequate workability and consistency to be properly mixed, placed and consolidated. Proper curing is also important to allow the cement to fully hydrate and gain strength over time. While concrete has advantages, it also has disadvantages like low tensile strength and requires careful mixing to ensure uniformity.
Concrete is a composite material made from aggregates, sand, cement, and water. It has high compressive strength but low tensile strength. Freshly mixed concrete must have adequate workability and consistency to be easily transported and placed, which depends on factors like water content, temperature, and use of chemical admixtures. Workability is often measured using the slump test. Improper mixing or placing can cause issues like segregation, bleeding, or honeycombing. Curing plays an important role in hydrating the cement and improving the properties of hardened concrete. Compressive strength is the most important property of hardened concrete, as it is indicative of load-bearing ability and related properties.
This document discusses different types of pavements and factors considered in pavement design. It describes flexible and rigid pavements, and notes that pavement refers to the top road surface layer, including sub-base and base layers below. The objectives of pavement are to transfer wheel loads, prevent water entry into subgrades, and provide a smooth surface. Factors in design include traffic load, subgrade soil, design life, climate, materials, drainage, and geometry. The CBR test method is explained for evaluating subgrade strength.
This document provides an overview of concrete, including its composition, properties, production process, and testing. Some key points:
- Concrete is a composite material made of cement, fine and coarse aggregates, and water. It can be classified based on its cementing material, mix proportions, performance specifications, grade, density, and place of casting.
- The production of concrete involves batching, mixing, transporting, placing, compacting, curing, and finishing. Proper batching and mixing are important to ensure uniform strength. Compaction removes entrapped air for maximum strength. Curing maintains moisture for proper hardening.
- Concrete properties depend on water-cement ratio, with maximum theoretical
This document summarizes the construction of rigid pavements. Rigid pavements use plain cement concrete slabs with dowel bars at joints for load transfer. They are used in areas with adverse conditions like heavy rainfall, poor soil/drainage, or extreme climate. Materials include cement, coarse and fine aggregates, and water. Construction involves subgrade preparation, forming slabs with joints, curing, and allowing time before opening to traffic. Joints include longitudinal, contraction, and expansion joints with filler and dowel bars to allow for expansion/contraction. Reinforcement improves strength and load distribution. Advantages include durability and low maintenance, while disadvantages include higher initial costs and traffic disruption during repairs.
Road construction pavements flexible rigidKumarS250747
This document discusses different types of road pavements and their construction. It describes flexible pavements like earthen, gravel and bituminous roads which deform under loading. Rigid pavements like cement concrete roads are also discussed, which act like beams and have high strength. Construction details are provided for soil stabilized roads, water bound macadam roads and cement concrete roads. Tests for materials and compaction requirements are mentioned.
The document discusses different types of pavements used for road construction including unsurfaced, surfaced, flexible, and rigid pavements. It provides details on the materials, design principles, properties, and construction procedures for various pavement types. These include earthen roads, gravel roads, water bound macadam roads, and cement concrete roads. The key components, types of joints, and construction methods for cement concrete pavements are also summarized.
This document provides information about different types of cement and concrete. It discusses the key constituents of concrete including cement, sand, gravel and water. It describes different types of cement such as Portland cement and their uses. The document also covers topics like mix design, properties and testing of concrete, and properties and testing of aggregates used in concrete.
The document discusses various materials used in construction including cement, aggregates, water, bricks, steel, and concrete. It provides details on testing and quality standards for each material. Proper selection and testing of materials is important for ensuring quality of construction. The document also covers mixing, placing, finishing, and curing of concrete. Curing allows concrete to gain strength and durability over time.
Shrinkage and plastic of concrete samples.pptGKRathod2
The document discusses various topics related to concrete, including destructive and non-destructive tests to determine concrete strength, factors affecting setting time and workability, methods to prevent issues like segregation and bleeding during concrete placement, and different curing techniques to promote strength development and durability. It provides details on tests like rebound hammer, ultrasonic pulse velocity and compression tests. It also explains concepts like slump loss, factors influencing cohesiveness, and precautions needed for hot weather concreting to prevent plastic shrinkage cracks.
The document discusses various topics related to concrete, including destructive and non-destructive tests to determine concrete strength, factors affecting setting time and workability, methods to prevent issues like segregation and bleeding during concrete placement, and different curing techniques to promote strength development and durability. It provides details on tests like rebound hammer, ultrasonic pulse velocity and compression tests. It also explains concepts like slump loss, influence of curing, and how to prevent plastic shrinkage cracks.
This document discusses ACI 301-5, which defines standard practices for structural concrete and concrete surface imperfections. It provides 13 definitions of common concrete defects, including plastic cracking, honeycombing, delamination, crazing, efflorescence, curling, bug holes, pop outs, alkali-silica reaction, dusting, concrete blisters, scaling, and blowup. It explains the causes and characteristics of each defect.
PDL’s Construction Development (Technical) Training Session-I_Structural.pptxChristopherThomas578171
This document provides an overview of structural construction materials and processes. It discusses aggregates, cement, water, reinforcement, admixtures, workability testing, water-cement ratios, concrete curing, embedded pipes, and cement and rebar storage. Formwork and scaffolding requirements are also outlined. Test procedures like slump tests and concrete cylinder tests are described. Typical reinforced concrete details are shown regarding clear cover, beam-column joints, splices and more.
This document discusses rigid pavements constructed using concrete slabs. Rigid pavements are commonly used when road conditions are adverse, such as heavy rainfall, poor soil/drainage, or extreme climate. The key materials used in concrete pavements include Portland cement, coarse and fine aggregates, water, and chemical admixtures. Reinforcement such as dowel bars and tie bars are also used. Concrete pavements consist of a soil subgrade, drainage layer, sub-base course, separation membrane, and concrete slabs with different types of joints. Common types of concrete pavements include jointed plain concrete pavement, jointed reinforced concrete pavement, and continuously reinforced concrete pavement. The document discusses the construction methods and equipment used for rigid
Properties of fresh and Hardened ConcreteVijay RAWAT
The document discusses various properties of fresh and hardened concrete. It describes workability, consistency, segregation, bleeding, mixing, placing, consolidating, and curing of fresh concrete. It also discusses compressive strength, tensile strength, modulus of elasticity, permeability, and durability of hardened concrete. The key properties of fresh concrete include workability, consistency, segregation, bleeding, setting time, and uniformity. Compressive strength is identified as the most important property of hardened concrete.
The document discusses various topics related to concrete including:
1. Slump and cube tests to measure workability and compressive strength of concrete.
2. Classification of concrete by strength and composition including lightweight and cellular concrete.
3. Factors that affect concrete such as hot weather, self-compacting, and pumped concrete.
4. Properties of fresh and hardened concrete including workability, segregation, and bleeding.
5. Types of cement and admixtures used to modify concrete properties.
6. Formwork used to mold wet concrete including materials, bracing, and types for tall buildings.
Metro Manila, the Philippines, serving as the junction between the South Luzon Expressway (SLEx) and Epifanio de los Santos Avenue (EDSA). It is also an interchange between the 2 train lines of Metro Manila, the MRT-3, which is over EDSA, and the PNR Metro Commuter, beside SLEx.
Highway Construction Materials and PracticeSenthamizhan M
Sub grade soil is an integral part of the road pavement structure as it provides the support to the pavement from beneath.
The sub grade soil and its properties are important in the design of pavement structure.
The main function of the sub grade is to give adequate support to the pavement and for this the sub grade should possess sufficient stability under adverse climatic and loading conditions.
Rigid pavements are constructed using reinforced concrete slabs that provide a strong wearing surface and base course. They are used in areas with adverse conditions like heavy rainfall, poor soil/drainage, or extreme climate. Materials for rigid pavements include Portland cement, coarse and fine aggregates, and water. Reinforcement includes dowel bars at joints. Rigid pavements have longitudinal and transverse joints, including contraction joints to relieve stresses, expansion joints to allow for expansion, and construction joints. They can be constructed using slipform pavers, fixed form pavers, or manual methods. Quality control ensures the concrete meets specifications. Traffic is only allowed after a minimum 28-day curing period.
An In-Depth Exploration of Natural Language Processing: Evolution, Applicatio...DharmaBanothu
Natural language processing (NLP) has
recently garnered significant interest for the
computational representation and analysis of human
language. Its applications span multiple domains such
as machine translation, email spam detection,
information extraction, summarization, healthcare,
and question answering. This paper first delineates
four phases by examining various levels of NLP and
components of Natural Language Generation,
followed by a review of the history and progression of
NLP. Subsequently, we delve into the current state of
the art by presenting diverse NLP applications,
contemporary trends, and challenges. Finally, we
discuss some available datasets, models, and
evaluation metrics in NLP.
Sachpazis_Consolidation Settlement Calculation Program-The Python Code and th...Dr.Costas Sachpazis
Consolidation Settlement Calculation Program-The Python Code
By Professor Dr. Costas Sachpazis, Civil Engineer & Geologist
This program calculates the consolidation settlement for a foundation based on soil layer properties and foundation data. It allows users to input multiple soil layers and foundation characteristics to determine the total settlement.
Covid Management System Project Report.pdfKamal Acharya
CoVID-19 sprang up in Wuhan China in November 2019 and was declared a pandemic by the in January 2020 World Health Organization (WHO). Like the Spanish flu of 1918 that claimed millions of lives, the COVID-19 has caused the demise of thousands with China, Italy, Spain, USA and India having the highest statistics on infection and mortality rates. Regardless of existing sophisticated technologies and medical science, the spread has continued to surge high. With this COVID-19 Management System, organizations can respond virtually to the COVID-19 pandemic and protect, educate and care for citizens in the community in a quick and effective manner. This comprehensive solution not only helps in containing the virus but also proactively empowers both citizens and care providers to minimize the spread of the virus through targeted strategies and education.
We have designed & manufacture the Lubi Valves LBF series type of Butterfly Valves for General Utility Water applications as well as for HVAC applications.
Data Communication and Computer Networks Management System Project Report.pdfKamal Acharya
Networking is a telecommunications network that allows computers to exchange data. In
computer networks, networked computing devices pass data to each other along data
connections. Data is transferred in the form of packets. The connections between nodes are
established using either cable media or wireless media.
Impartiality as per ISO /IEC 17025:2017 StandardMuhammadJazib15
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Sri Guru Hargobind Ji - Bandi Chor Guru.pdfBalvir Singh
Sri Guru Hargobind Ji (19 June 1595 - 3 March 1644) is revered as the Sixth Nanak.
• On 25 May 1606 Guru Arjan nominated his son Sri Hargobind Ji as his successor. Shortly
afterwards, Guru Arjan was arrested, tortured and killed by order of the Mogul Emperor
Jahangir.
• Guru Hargobind's succession ceremony took place on 24 June 1606. He was barely
eleven years old when he became 6th Guru.
• As ordered by Guru Arjan Dev Ji, he put on two swords, one indicated his spiritual
authority (PIRI) and the other, his temporal authority (MIRI). He thus for the first time
initiated military tradition in the Sikh faith to resist religious persecution, protect
people’s freedom and independence to practice religion by choice. He transformed
Sikhs to be Saints and Soldier.
• He had a long tenure as Guru, lasting 37 years, 9 months and 3 days
Online train ticket booking system project.pdfKamal Acharya
Rail transport is one of the important modes of transport in India. Now a days we
see that there are railways that are present for the long as well as short distance
travelling which makes the life of the people easier. When compared to other
means of transport, a railway is the cheapest means of transport. The maintenance
of the railway database also plays a major role in the smooth running of this
system. The Online Train Ticket Management System will help in reserving the
tickets of the railways to travel from a particular source to the destination.
2. What isPrecast Concrete?
Precast concrete means a concrete
member that is cast and cured at a
location other than its final designated
location. The use of reinforced concrete
is a relatively recent invention, usually
dated to 1848 when jean- Louis Lambot
became the first to use it.
Joseph Monier, a French gardener,
patented a design for reinforced
garden tubs in 1868, and later patented
reinforced concrete beams and posts
for railway and road guardrails.
4. INTRODUCTION :
4
+ +/- Additives
= +Concrete +
CONCRETE MIX DEPENDS ON :
Workability
5 categories:
•Very high
•High
•Medium
•Low
•Very low
Strength
Finished surface
Consistency
Durability = Quality of material, environmental effect
Compactibility
Mobility
Stability or cohesiveness
Water content in concrete mix
Nature of aggregate particles
(shape, surface, porosity)
5. SPECIFICATION OF CONCRETE :
Environmental
effect
Mixing Compacting Batching Transporting Placing Cement
content
Strength Water - cement ratio Aggregate - cement ratio
New site
•No old track record is available
•Requires at least 30 test strength results of
same grade of concrete
Old site
•Old track records
is available
Fly ash
GGBFS
TARGET MEAN STRENGTH OF CONCRETE:
Methods – determined by following situation
4
6. Formula to calculate TARGET MEAN STRENGTH (Fm) –
Fm = Fck + t X s
Where,
Fm = target mean strength
Fck = strength of concrete
( Strength achieved in 28 days )
t = constant
( probability of no. Of results fall below Fck )
s = standard deviation
( 30 hourly test results collected & tested daily using all 24hr samples mixed together )
AGGREGATES
Types --------------------------
Coarse Aggregates
Particles greater than
4.75mm.
E.g.- Gravel and
crushed rock
Downgraded Coarse Aggregates
Size may be either 40mm CAN and
20mm CA1 or 30mm CAN and
15mm CA1
Fine Aggregates
Particles passing
through 9.5mm sieve
E.g. - Natural sand
5
7. Properties ---
7
Physical
• Texture
• Structure
• Composition
Chemical
•Solubility
•Reactivity
•Weathering
resistance
S. Properties of
No. Aggregate
Influence on Concrete
property
1. Porosity Strength / absorption
2. Chemical stability Durability
3. Surface texture Bond grip
4. Shape, size Water demand, strength
Shape of Aggregates ---
Rounded gravel Irregular gravel Crushed rock
8. Fineness of Aggregates :
Influence the water demand of concrete mix
or strength.
8
Classified in 4 zones –----
Zone 1
Coarse sand
Zone 2
Normal sand
Zone 3
Fine sand
Zone 4
Very Fine sand
The selection of proportion of FA is given
by Department of Environment (DOE), UK
Maximum size of the Aggregates
(MAS) :
Mostly MAS is 10mm, 20mm or 40mm
is used.
For massive work, MAS is 150mm or
above is used.
Limitation of MAS :
Minimum dimension of concrete section to be cast is < 4 X MAS
Zone 1
Zone
2
Zone 3
Zone 4
9. Determination of Aggregate to Cement Ratio (A/C):
A/C ratio can be calculated if following factors are known or determined:
Shape of the aggregate
Maximum aggregate size (10mm,20mm,40mm)
Zone of aggregates (1,2,3,4)
Degree of workability
Water-to-cement ratio
If concrete ingredients consist of coarse crushed and natural fine aggregates then A/C is
adjusted as follows :
Determine A/C for crushed aggregates for the MAS fixed for the Mix (Say Aca)
Determine A/C for rounded or irregular gravel aggregates for MAS fixed for the Mix
(Say Afa)
Calculate A/C of the concrete mix (Say A’) as per formula
A’ = Aca (%of CA1+%of CA2) + Afa (%of FA1)
100 100
Where,
Aca = Actual coarse aggregate
Afa = Actual fine aggregate
FA1 = Fine aggregate (zone 1)
CA1 = Coarse aggregate (zone 1)
CA2 = Coarse aggregate (zone 2)
8
10. Age to strength relation – chemical compositions and fineness
Higher early strength
content of Tricalcium cilicate > Dicalcium cilicate
Finer ground cement > coarse ground cement
10
Concrete strength are generally specified by compressive
strengths and the structural design is worked out on that basis.
Exact information
of compressive strength
of concrete depends
on quality control
Parameters affecting
compressive strength
•Cement (quality and grade)
•Water (water-cement ratio)
•Cement storage andtransportation
•Cement packaging
•Aggregates
•Concrete workability
•Concrete placement
•Concrete compaction
•Curing of concrete
11. Equipments
Only steel or cast iron
Made up of three parts
1.two side flanges
2.base plate
3.nut bolts
Inside faced must be planed and machine
finished
All internal angles has to be accurate
Edges and joints must be cleaned
Surfaces should be coated by mould oil
Prevent mould from rusting
All parts should be bolted and then stored
in close room
Steel bar of 16mm dia.
600 mm length
Bullet head
12. Process for filling & compacting cube
mould
must be done into three layers
each app. 50mm
Must be placed using scoop
each layer is compacted using tamping rod
needs 35 stroke for 150mm &
25 stroke for 100mm
surface level should be planed
No air gaps in between or
scratches on surface
22
13. Process for identification , curing &
testing
On the surface level some
identification mark, number and
date has to be scratched and
same noted on paper
after removal from mould it should
immediately covered with damp jute
Transfer to a room having
humidity90% and temperature 27^
Keep the cube in curing pond of
clean water for 28 days
automatic compression
machine is better than manual
load application
Machine has a control on rate of
loading, we can apply various
loading while testing its strength
23
14. Precautions need to be taken while
testing
14
allow skilled workers only
Fresh water within 7 days only used for curing pond
Cubes has to be deep completely
Storage space has to be without any vibrations
Temperature control from 22 to 30 ^c.
There should not be loss in moisture while travelling from site to testing lab.
Afloat should be used to push the excess concrete after pouring third layer.
If the mix is too wet, allow water to drained out from mould.
15. Requirement of compression testing
15
machine
TOP PLATEN :
Harden and smooth faces
Fitted on cylinder concentric
with central point
must be accurate
Well calibrated, well certified
Having capacity to crush cube
Load applying rod
Concrete cube placing space
BOTTOM PLATEN :
Plain finished
Rigidly fixed on bearing block
Size more than cube size
Selection of machine depends
on size of cube and load
application
16. Acceptance criteria for compressive
Note the reading by applying
different loads from machine till the
cube crashes
Compressive strength should not be
less than the characteristic value
26
17. Modes of failures
USUAL FAILURES :
Equal cracking on all four sides
No damage to top and bottom faces
Cracks are vertical zigzag pattern
vertical faces breaks away leaving one
pyramid between
UNUSUAL FAILURES :
Crushed only at one side
Tensile or horizontal cracks only at one side
This indicates lower compressive strength
Reasons
Defects in machine
Faulty manual operation
Faulty casting of cube
Improper curing 27
18. Features
The division and specialization of the human
workforce.
The use of tools, machinery, and other
equipment, usually automated, in the
production of standard, interchangeable parts
and products.
Compared to site-cast concrete, precast
concrete erection is faster and less affected by
adverse weather conditions.
Plant casting allows increased
efficiency, high
quality control and greater control on
finishes.
4
19. Comparison
Site-cast
no transportation
the size limitation is
depending on the
elevation capacity only
lower quality because
directly affected by
weather
proper, large free space
required
Precast at plant
transportation and
elevation capacity limits
the size-
higher, industrialized
quality – less affected by
weather
no space requirement on
the site for fabrication
unlimited opportunities of
architectural appearance
option of standardized
components
5
20. Design concept for precast
concrete buildings
The design
concept of
the precast
buildings is
based on
1.build
ability.
2.economy
3.standardization of
precast
components.
6
25. Designconsiderations
final position and loads
transportation requirements – self load and
position during transportation
storing requirements – self load and position
during storing – (avoid or store in the same
position as it transported / built in)
lifting loads – distribution of lifting points –
optimal way of lifting (selection of lifting and
rigging tools)
vulnerable points (e.g. edges) – reduction of
risk (e.g. rounded edges)
10
26. Types of pre cast system
1. Large-panel systems
2. Frame systems
3. Slab-column systems with walls
4. Mixed systems
11
27. box-like structure.
both vertical and
horizontal elements are
load-bearing.
one-story high wall panels
(cross-wall system /
longitudinal wall system /
two way system).
one-way or two way
slabs.
12
1. Large-panel systems
28. 2. Frame systems
Components are usually
linear elements.
The beams are seated
on corbels of the pillars
usually with hinged-
joints (rigid connection
is also an option).
Joints are filled with
concrete at the site.
13
29. 3.Lift-slab systems
- partially precast in plant
(pillars) / partially precast on-
site (slabs).
- one or more storey high
pillars (max 5).
- up to 30 storey high
constructions.
- special designed joints and
temporary joints.
-slabs are casted on the
ground (one on top of the
other) – then lifted with crane
or special elevators.
14
30. Lift-slab procedure
15
1. pillars and the first package (e.g. 5 pieces) of slabs
prepared at ground level
2. lifting boxes are mounted on the pillars + a single slab
lifted to the first floor level
3-8. boxes are sequentially raised to higher positions to
enable the slabs to be lifted to their required
final position - slabs are held in a relative (temporary)
positions by a pinning system
32. Slabs:
• b) Hollow Core slab-
• Thicknesses of 4",6",8",10"and12"
• Spansup to 40’-0"
• Standard panel width =4’-0"
• Typical designations =4HC6 (4=panel width infeet, HC=
• Hollow Core, 6=slab thicknessininches)
a) Flat slab -
Standard panel width =4’-0"
Thickness of 4",6"and 8"
Spans up to 25’-0"
Typical designations =FS4(FS=Flat Slab, 4 =thickness of slab
33. Beams:
a) Rectangular Beam (RB)-
Typical beam width =12"or16"
Spans up to 50’-0"
Typical designation =16RB24 (16 =width in inches, 24=
depth ininches)
b) "L"and "IT"(inverted "Tee") beams (LBand IT)-
Typically used tosupport slabs, walls, masonry, and
beams
Typical beam width=12"
Depths of 20",28",36",44",52"and 60"
34.
35.
36. c) Double Tee Beam (DT) -
Combination beam and slab
Spans up to 100’-0"
Typical width=8’-0"
Depths of 12", 18", 24" and 32"
Designation =8DT24+2 (8 =width in feet, 24 =
depth, +2=2"topping)
37. d) Single Tee Beam (ST)-
Combination beam and slab
Spans up to 120’-0"
Typical width =8’-0"
Typical depths of 36"and 48"
Designation =8ST36+2(8 =width in feet, 24 =depth, +2=
2" topping)
38. Walls
Wall panels available in standard 8’-0" widths.
Can be flat, or have architectural features such as
window and door openings, ribs, reveals, textures,
sandwich (insulation built-in), sculptured,etc.
45. Weld Plates
Themostcommon method of attachment of precast
members isby use of steelweld plates. Typically, the
precast members have embedded plates that can
be used as weldingsurfacesforlooseconnecting
plates orangles (seebelow):
48. Precast Concrete
Slabs
• Used for floor and roof decks.
• Deeper elements (toward the right
below) span further than those that
are shallower (toward the left).
• Right: Hollow core slabs stacked at
the precasting plant.
49. Precast Concrete
Beams and Girders
• Provide support for slabs.
• The projecting reinforcing bars will bond with concrete cast
on site.
• Right: Inverted tee beams supported by precast columns.
M
50. Precast
Concrete
Columns and
Wall Panels
Provide support for
beam and slab
elements.
•Since these elements
carry mainly axial loads
with little bending
force, they may be
conventionally
reinforced without
prestressing.
•Or, long, slender
multistory elements
may be prestressed to
provide resistance to
bending forces during
handling and erection
(columns at right).
LEM
51. Precast Concrete
Columns and Wall
Panels
• Precast concrete wall panels
may be solid (right), hollow,
or sandwiched (with an
insulating core).
• Wall panels can be ribbed, to
increase their vertical span
capacity while minimizing
weight, or formed into other
special shapes (below).
52. Other Precast Concrete
Elements
• Precast concrete stairs
(below)
•Uniquely shaped structural
elements for a sports stadium
(right)
PRECAST, PRESTRESSED CONCRETE STRUCTURAL ELEM
53. Assembly Concepts for
Precast Concrete
Buildings
Vertical support can be
provided by precast
columns and beams
(above), wall panels
(below), or a combination
of all three.
•The choice of roof and
floor slab elements
depends mainly on span
requirements.
•Precast slab elements are
frequently also used with
other vertical loadbearing
systems such as sitecast
concrete, reinforced
masonry, or steel.
ELEM
54. Assembly Concepts for
Precast Concrete Buildings
•Above: Precast concrete structure
consisting of solid wall panels and hollow
core slabs.
•Below: A single story warehouse consisting
of double tees supported by insulated
sandwich wall panels.
55. Assembly Concepts for Precast
Concrete Buildings
•A parking garage structure consisting of
precast double tees supported by inverted
tee beams on haunches columns.
56. are manufactured in
casting beds, 800 ft or
more in length.
•High-strength steel
strands are strung the
length of the bed and
tensioned.
•Conventional
reinforcing, weld
plates, blockouts,
lifting loops, and other
embedded items are
added as needed.
•Concrete is placed.
Casting Hollow Core Planks
•Precast elements
Untensioned prestressing strands can be seen in the left-
most casting bed. In the bed second from the right, low-
slump concrete for hollow core slabs is being formed
over tensioned strands using an extrusion process. A
completed hollow core casting is visible at the far right.
57. Prestressing and
Reinforcing Steel
•Many precast elements contain
both prestressing strands and
conventional reinforcing.
•Right: The prestressing strands
for an AASHTO girder are
depressed into a shallow v- shape
to most efficiently resist tensile
forces in the beam. Shear stirrups
are formed from conventional
steel reinforcing.
58. Casting Hollow Core
Planks
•Once the concrete
has cured to sufficient
strength, the castings
are cut into sections
of desired length
(above).
•In some cases,
transverse bulkheads
are inserted to divide
the casting bed into
sections before
concrete is placed. In
this case, only the
prestressing strands
need to be cut to
separate the sections
(below).
59. Casting Hollow
Core Planks
• Individual sections
are lifted from the
casting bed (right) and
stockpiled to await
shipping to the
construction site.
62. Advantages Of precast
concrete construction
Quick erection times
Possibility of conversion, disassembling
and moving to another site
Possibility of erection in areas where a
traditional construction practice is not
possible or difficult
Low labor intensivity
Reduce wastage of materials
Easier management of construction sites
Better overall construction quality
Ideal fit for simple and complex structures
22
63. Disadvantages ofPrecast
Concrete Construction
Somewhat limited building design flexibility
Very heavy members
Camber in beams and slabs
Very small margin forerror
Connections may be difficult
Because panel size is limited, precast concrete can not be
used for two-way structural systems.
Economics of scale demand regularly shaped buildings.
Need for repetition of forms will affect building design.
Joints between panels are oftenexpensive and
complicated.
Skilled workmanship is required in the application of the
panel on site.
Cranes are required tolift panels.
64. Limitations
size of the units.
location of window openings has a
limited variety.
joint details are predefined.
site access and storage capacity.
require high quality control.
enable interaction between design
phase and production planning.
difficult to handling & transporting.
23
65. Popular UsesofPrecast
Concrete
Concrete curtain walls
As an exterior cladding(may include
exposed aggregate)
For structural walls
Ability to precast in threedimensions
allows precast panels to form parts of
mechanical systems
66. Scheduling
some approximate data for installation
emplacement of hollow core floor slabs -
300 m2/day
erection of pillars/columns - 8 pieces/day
emplacement of beams - 15 pieces/day
emplacement of double tee slabs - 25
pieces/day
emplacement of walls - 15 pieces/day
construction of stair and elevator shafts -
2 floors/day
24
67. Examples….
25
The hospital will feature multi-trade prefabricated racks in the corridors, an
approach that is still new in the U.S.
69. Conclusion
27
oThe use of prefabrication and preassembly is
estimated to have almost doubled in the last 15
years, increasing by 86%.
oThe use of precast concrete construction can
significantly reduce the amount of construction waste
generated on construction sites.
o Reduce adverse environmental impact on sites.
o Enhance quality control of concreting work.
o Reduce the amount of site labour.
o Increase worker safety .
o Other impediments to prefabrication and
preassembly are increased transportation
difficulties, greater inflexibility, and more advanced
procurement requirements.
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