This document is a mini project report submitted by Sandeep Kumar to fulfill the requirements for a Bachelor of Technology degree in Civil Engineering. The report describes designing and drawing a flat slab structure using the Indian Standard Code. It provides an introduction to flat slab construction, advantages of flat slabs like flexibility in design and reduced building height. It also discusses code regulations, design steps, and concludes with designing a flat slab according to the IS code.
This document discusses the design of flat slab structures. It begins by defining a flat slab as a type of slab supported directly on columns without beams. It then provides details on the types of flat slabs, their common uses in buildings, and benefits such as flexibility in layout and reduced construction time. The document goes on to discuss key design considerations for flat slabs including thickness, drops, column heads, and methods of analysis. It focuses on the direct design method and provides limitations for its use.
The document discusses reinforced cement concrete (RCC) structures. It describes two types of building structures - load bearing, where walls transmit loads directly to the ground, and framed structures, where loads are transferred through RCC beams, columns, and slabs. It also discusses design loads on buildings including dead loads from structural weight and live loads. Common RCC structural elements like beams, slabs, shear walls and elevator shafts are described. Raw materials, advantages, specifications, common ratios, one-way and two-way slabs, and examples of RCC structures are covered.
The document provides details on the design of a reinforced concrete column footing to support a column with a load of 1100kN. It includes calculating the footing size as a 3.5m x 3.5m square to support the load, determining the reinforcement with 12mm diameter bars at 100mm spacing, and checking that the design meets requirements for bending capacity, shear strength, and development length. The step-by-step worked example shows how to analyze and detail the reinforcement of the column footing.
The document discusses the design of staircases. It begins by defining key components of staircases like treads, risers, stringers, etc. It then describes different types of staircases such as straight, doglegged, and spiral. The document outlines considerations for designing staircases like dimensions, loads, and structural behavior. It provides steps for geometric design, load calculations, structural analysis, reinforcement design, and detailing of staircases. Numerical examples are also included to illustrate the design process.
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.
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.
Framed structures are building skeleton frameworks formed by columns and beams. There are two main types: in-situ reinforced concrete frames and prefabricated frames. Rectangular framed structures use columns and beams arranged at right angles to support floors, walls, and roofs. They are commonly used for multi-story buildings like offices, schools, and hospitals. Framed structures provide large open floor plans and are adaptable to different shapes. Earthquake-resistant features in framed structures include shear walls, moment-resisting frames, and braced structures which resist lateral forces during seismic activity.
The document discusses retaining walls and includes:
- Definitions of retaining walls and their parts
- Common types of retaining walls including gravity, semi-gravity, cantilever, counterfort and bulkhead walls
- Earth pressures like active, passive and at rest pressures
- Design principles for stability against sliding, overturning and bearing capacity
- Drainage considerations for retaining walls
- Theories for analyzing earth pressures like Rankine and Coulomb's theories
- Sample design calculations and problems for checking stability of retaining walls
This document discusses the design of flat slab structures. It begins by defining a flat slab as a type of slab supported directly on columns without beams. It then provides details on the types of flat slabs, their common uses in buildings, and benefits such as flexibility in layout and reduced construction time. The document goes on to discuss key design considerations for flat slabs including thickness, drops, column heads, and methods of analysis. It focuses on the direct design method and provides limitations for its use.
The document discusses reinforced cement concrete (RCC) structures. It describes two types of building structures - load bearing, where walls transmit loads directly to the ground, and framed structures, where loads are transferred through RCC beams, columns, and slabs. It also discusses design loads on buildings including dead loads from structural weight and live loads. Common RCC structural elements like beams, slabs, shear walls and elevator shafts are described. Raw materials, advantages, specifications, common ratios, one-way and two-way slabs, and examples of RCC structures are covered.
The document provides details on the design of a reinforced concrete column footing to support a column with a load of 1100kN. It includes calculating the footing size as a 3.5m x 3.5m square to support the load, determining the reinforcement with 12mm diameter bars at 100mm spacing, and checking that the design meets requirements for bending capacity, shear strength, and development length. The step-by-step worked example shows how to analyze and detail the reinforcement of the column footing.
The document discusses the design of staircases. It begins by defining key components of staircases like treads, risers, stringers, etc. It then describes different types of staircases such as straight, doglegged, and spiral. The document outlines considerations for designing staircases like dimensions, loads, and structural behavior. It provides steps for geometric design, load calculations, structural analysis, reinforcement design, and detailing of staircases. Numerical examples are also included to illustrate the design process.
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.
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.
Framed structures are building skeleton frameworks formed by columns and beams. There are two main types: in-situ reinforced concrete frames and prefabricated frames. Rectangular framed structures use columns and beams arranged at right angles to support floors, walls, and roofs. They are commonly used for multi-story buildings like offices, schools, and hospitals. Framed structures provide large open floor plans and are adaptable to different shapes. Earthquake-resistant features in framed structures include shear walls, moment-resisting frames, and braced structures which resist lateral forces during seismic activity.
The document discusses retaining walls and includes:
- Definitions of retaining walls and their parts
- Common types of retaining walls including gravity, semi-gravity, cantilever, counterfort and bulkhead walls
- Earth pressures like active, passive and at rest pressures
- Design principles for stability against sliding, overturning and bearing capacity
- Drainage considerations for retaining walls
- Theories for analyzing earth pressures like Rankine and Coulomb's theories
- Sample design calculations and problems for checking stability of retaining walls
Purlins are roof framing members that span parallel to the building eave and support roof decking or sheeting. They are supported by rafters or walls and spaced on main rafters such that roof sheets overlap by at least 150mm. Purlins are typically spaced between 1.35 to 1.4 meters and can be made of I-sections, channels, angles, or cold formed C or Z sections. Cleat angles, also called seat angles, are short lengths of angle iron used as brackets to support purlins.
Composite structure of concrete and steel.Suhailkhan204
This document discusses composite structures, which combine steel and concrete materials. The key elements of composite structures are composite deck slabs, beams, and columns, along with shear connectors. Composite structures take advantage of concrete's compressive strength and steel's tensile strength. They provide benefits like increased load capacity, stiffness, fire resistance, and cost savings compared to traditional steel or concrete construction alone. An example project, the Millennium Tower in Vienna, is described. The document analyzes costs and concludes that composite structures are best suited for high-rise buildings due to reduced weight, increased ductility, and savings of around 10% compared to reinforced concrete.
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.
This document provides guidance on the design of lacing and battens for built-up compression members. It discusses the key design considerations and calculations for both single and double lacing systems, including the angle of inclination, slenderness ratio, effective lacing length, bar width and thickness. Similar guidelines are given for battens, covering spacing, thickness, effective depth, transverse shear and overlap. The document also includes an example problem on designing a slab foundation for a column with given load and material properties.
A grid slab is a type of building material that has two-directional reinforcement in the shape of a waffle. It can be used as both ceilings and floors, especially in areas requiring large spans with fewer columns. Features include panels on a 1 meter grid with trench mesh or individual bars. Grid slabs use less concrete and steel than conventional slabs while providing strength and resistance to cracking and sagging. Construction involves arranging a framework, fixing connectors and pods, then removing forms. Services like HVAC, plumbing and wiring can be run through holes in modified grid slabs. Benefits include flexibility, lighter weight, speed of construction, vibration control and fire resistance. Famous structures using grid slabs include terminals,
This document discusses different types of reinforced concrete slabs, including one-way slabs, two-way slabs, flat slabs, and ribbed slabs. One-way slabs are supported on two sides and bend in one direction, while two-way slabs are supported on all four sides and bend in both directions. Flat slabs do not have beams and loads are transferred directly to columns, providing a plain ceiling. Ribbed slabs contain reinforced concrete ribs spaced no more than 1 meter apart between which the slab spans.
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.
Stairs are designed to provide access between different levels of a building. The document defines stairs and their key components like treads, risers, landings, etc. It discusses different types of stairs like straight, turning, circular and geometrical. The materials used for stairs construction are also explained, including stone, timber, RCC, brick and metal stairs. Technical terms related to stairs are defined. In the end, common stair types are identified from images.
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.
This resource material is exclusively for the purpose of knowledge dissemination for the use of Civil engineering Fraternity, professionals & students.
This file contains state of art techniques adopted & practiced as per IS456 code provisions for analysis design & detailing of flat slab structural systems.
The presentation aims to provide clear,concise, technical details of flat slabs design.
The presentation deals with structural actions & behavior of flat slabs with visual representations obtained through finite element analysis.
The knowledge gained can be used for designing building structures frequently encountered in construction.
The presentation covers an important feature of slab systems supported on rigid & flexible support & clearly demarcates the minimum beam dimensions required to consider the supports to be either rigid or flexible.
The presentation alsoincludes clear technical drawings to highlight the importance of detailing w.r.t. rebar lay out - positioning & curtailment. Typical section drawing through middle & column strips are also included for visualizing rebar patterns in 3 -d views.
This presentation is an outcome of series of lectures for undergrad & grad students studying in civil engineering.
My next presentation would be on Analysis & design of deep beams.
Kindly mail me ( vvietcivil@gmail.com) your questions & valuable feedback.
The document discusses structural steel, including its composition, properties, types, and applications in construction. It describes how steel is made from iron with added elements, and its varying properties based on carbon content. The types discussed are mild steel, medium carbon steel, and high carbon steel. Common structural steel applications mentioned include beams, columns, trusses, and framing for buildings like airports and stadiums.
Prestressed concrete is concrete that is placed under compression using tensioned steel strands, cables, or bars. This is done through either pre-tensioning or post-tensioning. In pre-tensioning, the steel components are tensioned before the concrete is poured, while in post-tensioning, the steel components are tensioned after the concrete has hardened. Prestressed concrete provides benefits over reinforced concrete like lower construction costs, thinner structural elements, and longer spans between supports.
Footings are structural members that support columns and walls and transmit their loads to the soil. Different types of footings include wall footings, isolated/single footings, combined footings, cantilever/strap footings, continuous footings, rafted/mat foundations, and pile caps. Footings must be designed to safely carry and transmit loads to the soil while meeting code requirements regarding bearing capacity, settlement, reinforcement, and shear strength. A proper footing design involves determining loads, allowable soil pressure, reinforcement requirements, and assessing settlement.
This document discusses raft/mat foundations, including:
- A raft foundation is a thick reinforced concrete slab that supports columns and transmits loads into the soil. It is used for structures with large or uneven column loads.
- Types of raft foundations include flat plate, thickened under columns, beam and slab, box structures, and mats on piles.
- Construction involves soil testing, excavation, reinforcement placement, forming, concrete pouring, and curing. Raft foundations are economic and reduce differential settlement but require treatment for point loads.
A shear wall is a vertical structural element used to resist horizontal forces such as wind and seismic forces. Shear walls are generally used in high-rise buildings where the effects of wind and seismic forces are more significant. Shear walls are usually provided along both the length and width of buildings and act like vertically-oriented beams that carry earthquake loads downwards to the foundation. Common types of shear walls include reinforced concrete, concrete block, steel, plywood, and mid-ply shear walls. Shear walls must provide the necessary lateral strength to resist horizontal earthquake forces and lateral stiffness to prevent excessive side-sway of the structure.
Slabs are structural members that support transverse loads and transfer them to supports via bending. They are commonly used as floors and roofs. One-way slabs bend in only one direction across the shorter span like a wide beam, while two-way slabs bend in both directions if the ratio of longer to shorter span is less than or equal to 2. Design of one-way slabs involves calculating bending moment and shear force, selecting reinforcement ratio and bar size, and checking deflection, shear, and development length.
Joints are easy to maintain and are less detrimental than uncontrolled or uneven cracks. Concrete expands & shrinks with variations in moisture and temp. The overall affinity is to shrink and this can cause cracking at an early age. Uneven cracks are unpleasant and difficult to maintain but usually do not affect the integrity of concrete.
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The document discusses flat grid or waffle slab systems. It defines waffle slabs as having two-directional reinforcement on the outside, giving it a waffle-like shape. This provides stability without using much material, making it suitable for large flat areas like foundations and floors. Waffle slabs are used in industrial and commercial buildings where large spans are needed with few columns. They provide features like using less concrete and steel than traditional slabs while providing strength and resistance to cracking and sagging. The document outlines the production, design, and construction process for waffle slabs and notes some iconic landmarks that have utilized this system.
Slab is a thin concrete structure used for flooring that can be square, rectangular, or circular. Slabs vary in thickness from 4-6 inches depending on load and are made of cement, coarse aggregate, fine aggregate, and reinforcement bars. There are several types of slabs including one-way slabs which carry load in one direction, two-way slabs which carry load in two directions, joist slabs which have concrete ribs for support, and precast slabs which are constructed off-site and transported. Other slab types include flat plates, flat slabs, waffle slabs, hollow core slabs, and composite slabs which incorporate a steel deck.
This document summarizes the key aspects of a flat plate concrete slab design presented by Md. Shariful Alam. It defines a flat plate as a reinforced concrete slab supported directly by concrete columns without beams. It discusses the uses of column heads and drop panels to increase shear strength and moment capacity. Benefits of flat plate include flexibility in room layout, reduced building height and construction time, and higher buildability scores. Design considerations like crack control, punching shear, construction loads, and lateral stability are also outlined.
shariful alam ( presentation on flat plate )sharifulaust
This document summarizes the key aspects of a flat plate concrete slab design presented by Md. Shariful Alam. It defines a flat plate as a reinforced concrete slab supported directly by concrete columns without beams. It discusses the uses of column heads and drop panels to increase shear strength and moment capacity. Benefits of flat plate include flexibility in room layout, reduced building height and construction time, and higher buildability scores. Design considerations like crack control, punching shear, construction loads, and lateral stability are also outlined.
Purlins are roof framing members that span parallel to the building eave and support roof decking or sheeting. They are supported by rafters or walls and spaced on main rafters such that roof sheets overlap by at least 150mm. Purlins are typically spaced between 1.35 to 1.4 meters and can be made of I-sections, channels, angles, or cold formed C or Z sections. Cleat angles, also called seat angles, are short lengths of angle iron used as brackets to support purlins.
Composite structure of concrete and steel.Suhailkhan204
This document discusses composite structures, which combine steel and concrete materials. The key elements of composite structures are composite deck slabs, beams, and columns, along with shear connectors. Composite structures take advantage of concrete's compressive strength and steel's tensile strength. They provide benefits like increased load capacity, stiffness, fire resistance, and cost savings compared to traditional steel or concrete construction alone. An example project, the Millennium Tower in Vienna, is described. The document analyzes costs and concludes that composite structures are best suited for high-rise buildings due to reduced weight, increased ductility, and savings of around 10% compared to reinforced concrete.
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.
This document provides guidance on the design of lacing and battens for built-up compression members. It discusses the key design considerations and calculations for both single and double lacing systems, including the angle of inclination, slenderness ratio, effective lacing length, bar width and thickness. Similar guidelines are given for battens, covering spacing, thickness, effective depth, transverse shear and overlap. The document also includes an example problem on designing a slab foundation for a column with given load and material properties.
A grid slab is a type of building material that has two-directional reinforcement in the shape of a waffle. It can be used as both ceilings and floors, especially in areas requiring large spans with fewer columns. Features include panels on a 1 meter grid with trench mesh or individual bars. Grid slabs use less concrete and steel than conventional slabs while providing strength and resistance to cracking and sagging. Construction involves arranging a framework, fixing connectors and pods, then removing forms. Services like HVAC, plumbing and wiring can be run through holes in modified grid slabs. Benefits include flexibility, lighter weight, speed of construction, vibration control and fire resistance. Famous structures using grid slabs include terminals,
This document discusses different types of reinforced concrete slabs, including one-way slabs, two-way slabs, flat slabs, and ribbed slabs. One-way slabs are supported on two sides and bend in one direction, while two-way slabs are supported on all four sides and bend in both directions. Flat slabs do not have beams and loads are transferred directly to columns, providing a plain ceiling. Ribbed slabs contain reinforced concrete ribs spaced no more than 1 meter apart between which the slab spans.
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.
Stairs are designed to provide access between different levels of a building. The document defines stairs and their key components like treads, risers, landings, etc. It discusses different types of stairs like straight, turning, circular and geometrical. The materials used for stairs construction are also explained, including stone, timber, RCC, brick and metal stairs. Technical terms related to stairs are defined. In the end, common stair types are identified from images.
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.
This resource material is exclusively for the purpose of knowledge dissemination for the use of Civil engineering Fraternity, professionals & students.
This file contains state of art techniques adopted & practiced as per IS456 code provisions for analysis design & detailing of flat slab structural systems.
The presentation aims to provide clear,concise, technical details of flat slabs design.
The presentation deals with structural actions & behavior of flat slabs with visual representations obtained through finite element analysis.
The knowledge gained can be used for designing building structures frequently encountered in construction.
The presentation covers an important feature of slab systems supported on rigid & flexible support & clearly demarcates the minimum beam dimensions required to consider the supports to be either rigid or flexible.
The presentation alsoincludes clear technical drawings to highlight the importance of detailing w.r.t. rebar lay out - positioning & curtailment. Typical section drawing through middle & column strips are also included for visualizing rebar patterns in 3 -d views.
This presentation is an outcome of series of lectures for undergrad & grad students studying in civil engineering.
My next presentation would be on Analysis & design of deep beams.
Kindly mail me ( vvietcivil@gmail.com) your questions & valuable feedback.
The document discusses structural steel, including its composition, properties, types, and applications in construction. It describes how steel is made from iron with added elements, and its varying properties based on carbon content. The types discussed are mild steel, medium carbon steel, and high carbon steel. Common structural steel applications mentioned include beams, columns, trusses, and framing for buildings like airports and stadiums.
Prestressed concrete is concrete that is placed under compression using tensioned steel strands, cables, or bars. This is done through either pre-tensioning or post-tensioning. In pre-tensioning, the steel components are tensioned before the concrete is poured, while in post-tensioning, the steel components are tensioned after the concrete has hardened. Prestressed concrete provides benefits over reinforced concrete like lower construction costs, thinner structural elements, and longer spans between supports.
Footings are structural members that support columns and walls and transmit their loads to the soil. Different types of footings include wall footings, isolated/single footings, combined footings, cantilever/strap footings, continuous footings, rafted/mat foundations, and pile caps. Footings must be designed to safely carry and transmit loads to the soil while meeting code requirements regarding bearing capacity, settlement, reinforcement, and shear strength. A proper footing design involves determining loads, allowable soil pressure, reinforcement requirements, and assessing settlement.
This document discusses raft/mat foundations, including:
- A raft foundation is a thick reinforced concrete slab that supports columns and transmits loads into the soil. It is used for structures with large or uneven column loads.
- Types of raft foundations include flat plate, thickened under columns, beam and slab, box structures, and mats on piles.
- Construction involves soil testing, excavation, reinforcement placement, forming, concrete pouring, and curing. Raft foundations are economic and reduce differential settlement but require treatment for point loads.
A shear wall is a vertical structural element used to resist horizontal forces such as wind and seismic forces. Shear walls are generally used in high-rise buildings where the effects of wind and seismic forces are more significant. Shear walls are usually provided along both the length and width of buildings and act like vertically-oriented beams that carry earthquake loads downwards to the foundation. Common types of shear walls include reinforced concrete, concrete block, steel, plywood, and mid-ply shear walls. Shear walls must provide the necessary lateral strength to resist horizontal earthquake forces and lateral stiffness to prevent excessive side-sway of the structure.
Slabs are structural members that support transverse loads and transfer them to supports via bending. They are commonly used as floors and roofs. One-way slabs bend in only one direction across the shorter span like a wide beam, while two-way slabs bend in both directions if the ratio of longer to shorter span is less than or equal to 2. Design of one-way slabs involves calculating bending moment and shear force, selecting reinforcement ratio and bar size, and checking deflection, shear, and development length.
Joints are easy to maintain and are less detrimental than uncontrolled or uneven cracks. Concrete expands & shrinks with variations in moisture and temp. The overall affinity is to shrink and this can cause cracking at an early age. Uneven cracks are unpleasant and difficult to maintain but usually do not affect the integrity of concrete.
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types of concrete expansion joints
construction joint concrete
control joints in concrete
The document discusses flat grid or waffle slab systems. It defines waffle slabs as having two-directional reinforcement on the outside, giving it a waffle-like shape. This provides stability without using much material, making it suitable for large flat areas like foundations and floors. Waffle slabs are used in industrial and commercial buildings where large spans are needed with few columns. They provide features like using less concrete and steel than traditional slabs while providing strength and resistance to cracking and sagging. The document outlines the production, design, and construction process for waffle slabs and notes some iconic landmarks that have utilized this system.
Slab is a thin concrete structure used for flooring that can be square, rectangular, or circular. Slabs vary in thickness from 4-6 inches depending on load and are made of cement, coarse aggregate, fine aggregate, and reinforcement bars. There are several types of slabs including one-way slabs which carry load in one direction, two-way slabs which carry load in two directions, joist slabs which have concrete ribs for support, and precast slabs which are constructed off-site and transported. Other slab types include flat plates, flat slabs, waffle slabs, hollow core slabs, and composite slabs which incorporate a steel deck.
This document summarizes the key aspects of a flat plate concrete slab design presented by Md. Shariful Alam. It defines a flat plate as a reinforced concrete slab supported directly by concrete columns without beams. It discusses the uses of column heads and drop panels to increase shear strength and moment capacity. Benefits of flat plate include flexibility in room layout, reduced building height and construction time, and higher buildability scores. Design considerations like crack control, punching shear, construction loads, and lateral stability are also outlined.
shariful alam ( presentation on flat plate )sharifulaust
This document summarizes the key aspects of a flat plate concrete slab design presented by Md. Shariful Alam. It defines a flat plate as a reinforced concrete slab supported directly by concrete columns without beams. It discusses the uses of column heads and drop panels to increase shear strength and moment capacity. Benefits of flat plate include flexibility in room layout, reduced building height and construction time, and higher buildability scores. Design considerations like crack control, punching shear, construction loads, and lateral stability are also outlined.
The document is a student project report proposing alternative construction systems for the floor, wall, roof, and basement of a Nature Appreciation Centre. It includes sections on the existing and proposed construction systems, precedent studies, materials used, advantages and disadvantages of each system, and working drawings. The proposed changes include using reinforced concrete for the ground floor, composite steel decking for the first floor, brick walls with vinyl siding and plastered interiors, and a new basement level.
1) The document summarizes a site visit report to a construction site of two apartment blocks and a serviced apartment.
2) During the visit, students observed various construction materials, processes and equipment used at the site including formwork, scaffolding, concrete and safety practices.
3) Key areas discussed included the types of formwork used for slabs, beams and columns, the use of independent scaffolding outside and inside the building, and details on the grade of concrete poured.
This document provides a report on a technical site visit to an Andes Construction site. The following key points are made:
- The site visit allowed students to understand construction processes in practice compared to theory, and exposed them to the working environment and safety practices.
- The site was separated into three zones, with the foundation completed in Zone A and in progress in Zone B. Pile cap foundation was used due to unstable soil conditions.
- Advantages of pile cap foundations include increased bearing capacity and ability to use in areas with underground water pressure. Disadvantages include higher costs and need for heavy equipment.
- Concrete grade 25 was used for casting beams, columns, slabs and foundations. Light
This document provides information on cast-in-place and pre-cast concrete, as well as different types of concrete slabs and floor systems. It defines cast-in-place and pre-cast concrete, compares their advantages, and provides details on useful information for each method. It also describes different types of concrete slabs - flat slab, flat plate, waffle slab, ribbed floor slab, and lift slab. Finally, it discusses different types of floor systems including metal decking and concrete floor systems.
The document provides details about an internship at Srushti Engineers & Valuers company. It includes information about the company profile such as its founder, location, and years in operation. It also describes several completed construction projects the company has worked on. The main focus of the internship is a residential building project including plans, cost estimates, and construction methodology for activities like excavation, plinth beams, brick masonry, RCC slabs, plastering and flooring. The intern aims to gain practical experience and apply their theoretical knowledge through this project.
The document is a site visit report for a construction project comprising 96 residential units. It includes an introduction, objectives of the site visit, summaries of the site layout and house types, and observations of construction materials and methods used - including scaffolding, formwork, pad footings, and reinforced concrete. Photos supplement the technical descriptions and the conclusion reflects on the learning experience gained from directly observing construction practices.
The site visit report provides details of a site visit to a construction site in Hulu Selangor where 96 units of semi-detached houses are being built. Key observations from the site include: pad footings being used to support columns, with Type 1 normal cement and high tensile steel rebar used for reinforcement. Formwork is constructed from timber and scaffolding is used. The report describes the materials and construction methods observed, including excavation, pad footing construction, and the use of formwork, rebar, concrete and other building materials. Safety procedures and documentation like the project information board were also noted.
This site visit summary provides the following key details in 3 sentences:
The site visit was to a residential construction project comprising 42 bungalow units. Students learned about the construction processes on site such as foundations, concrete framing, and building materials used. The site visit provided a valuable hands-on learning experience for the students to see first-hand what they have learned in the classroom applied in a real construction project.
1) Pre-engineered buildings (PEBs) offer advantages over conventional construction including reduced construction time (by at least 50%), lower costs due to standardized design and factory assembly, and flexibility for expansion.
2) PEBs are widely used for industrial and commercial buildings globally but are a relatively new concept in India, gaining popularity since the late 1990s. The Indian PEB market and manufacturing capacity is growing significantly.
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Designing and drawing of flat slab with the help of i.s code
1. A
Mini Project Report
On
DESIGNING AND DRAWING OF FLAT SLAB WITH THE HELP OF
I.S CODE
In partial fulfillments for the degree of
Bachelor of Technology
In
Civil Engineering
SUBMITTED BY
SANDEEP KUMAR
ROLL NO :-XXXXXXX
Under the Guidance of
Mr. RAJESH MEENA
DEPARTMENT OF CIVIL ENGINEERING
NOIDA INSTITUTE OF ENGINEERING AND TECHNOLOGY
Greater Noida, Uttar Pradesh APJ Abdul kalam Technical University
2019
2. ii
CERTIFICATE
Certified that minor project work entitled “ DESIGNING AND DRAWING OF FLAT SLAB
WITH THE HELP OF I.S CODE ” is a bonafide work carried out in the 7th
semester by
SANDEEP KUMAR in partial fulfilment for the award of Bachelor of technology in Civil
Engineering from “ NOIDA INSTITUTE OF ENGINEERING AND TECHNOLOGY ”
Greater Noida , during the academic year 2019-2020.
Project Guide : Project coordinator :
Mr. RAJESH MEENA Mr. RAJESH MEENA
3. iii
ACKNOWLEDGEMENT
I feel very proud to say that due to keen knowledge of the faculty of the Civil Department of
the Noida Institute Of Engineering and technology .It was very easy for me to learn a lot of
knowledge regarding the “DESIGNING AND DRAWING OF FLAT SLAB WITH THE
HELP OF I.S CODE”.
I am greatly thankful to our guide Mr. RAJESH MEENA for his kind support and guidance
to successfully complete my Project . I have highly benefited by this Project and have gained
a lot of knowledge about the various problems of designing & drawing of the flat slab using
I.S CODE used in a construction site.
Finally I would like to thanks all the faculty members and senior teachers who have helped me
and co-operated with me during my project work.
NAME : SANDEEP KUMAR
ROLL.NO: xxxxxxxx
4. iv
TABLE OF CONTENT
1. Introduction ........................................................................................... 1
1.1 Types of flat slab .......................................................................... 2
1.2 Use of column head ...................................................................... 2
1.3 Use of drop panels ........................................................................ 2
2. Advantages of flat slab ........................................................................... 4
2.1 Thickness of flat slab ................................................................... 4
2.2 Types of flat slab design ............................................................... 4
3. Benefits of flat slab ................................................................................ 5
4. Need of flat slab ...................................................................................... 6
5. Code regulations .................................................................................... 8
5.1 Methods of analysis ..................................................................... 8
5.1.1 Direct design method ................................................. 8
5.1.2 Equivalent frame method ........................................... 9
6. Design steps ............................................................................................. 10
6.1 Advantages .................................................................................. 10
6.2 Disadvantages .............................................................................. 10
7. Design of flat slab by IS code ………………………………………........ 11
8. Conclusion ............................................................................................... 15
7. References ................................................................................................ 16
5. v
LISTS OF FIGURES
Sr.no Figure Page no:
1.1 Flat slab 1
1.2 Types of flat slab 2
1.3 Flat slab with columns 3
4.1 Deflection diagrams 6
5.1 Design moment 9
6. vi
ABSTRACT
Designing of flat slab and drawing using the I.S CODE is very important for any construction
site and any project its help us to prepare a masonry structures likes :-
• Parking desk
• Commercial buildings
• Hotels
• Warehouses
• Places where beam are not required
Flat Slabs are considered suitable for most of the construction and for asymmetrical column
layouts like floors with curved shapes and ramps etc. The advantages of applying flat slabs are
many like depth solution, flat soffit and flexibility in design layout.
Even though building flat slabs can be an expensive affair but gives immense freedom to
architects and engineers the luxury of designing.
Structures having floors with irregular supports, large openings or bears heavy loads,
application of finite- element analysis is supposed to be very advantageous. Great thought is
put into choosing material properties or installing loads on the structures. Deflections and
cracked width can also be calculated using Finite- element analysis.
KEY WOEDS : ( Slab , Concrete , Support , Columns , Beams)
7. 1
CHAPTER 1
INTRODUCTION
Flat slab is a reinforced concrete slab supported directly by concrete columns without the use
of beams. Flat slab is defined as one sided or two-sided support system with sheer load of the
slab being concentrated on the supporting columns and a square slab called ‘drop panels’.
Drop panels play a significant role here as they augment the overall capacity and sturdiness of
the flooring system beneath the vertical loads thereby boosting cost effectiveness of the
construction. Usually the height of drop panels is about two times the height of slab.
FIG 1.1 FLAT SLAB
Flat Slabs are considered suitable for most of the construction and for asymmetrical column
layouts like floors with curved shapes and ramps etc. The advantages of applying flat slabs are
many like depth solution, flat soffit and flexibility in design layout.Even though building flat
slabs can be an expensive affair but gives immense freedom to architects and engineers the
luxury of designing.
Benefit of using flat slabs are manifold not only in terms of prospective design and layout
efficacy but is also helpful for total construction process especially for easing off installation
procedures and saving on construction time. If possible, try to do away with drop panels as
much as possible and try to make the best use of thickness of flat slabs. The reason is to permit
the benefits of flat soffits for the floor surface to be maintained, ensure drop panels are cast as
part of the column.
8. 2
1.1TYPES OF FLAT SLAB CONSTRUCTION
Following are the types of flab slab construction:-
• Simple flat slab.
• Flat slab with drop panels.
• Flat slab with column head.
• Flat slab with both drop panels and column head.
Fig 1.2 TYPES OF FLAT SLABS
1.2Uses of Column Heads
• It increase shear strength of slab.
• It reduce the moment in the slab by reducing the clear or effective span.
9. 3
1.3 Uses of Drop Panels
• It increase shear strength of slab
• It increase negative moment capacity of slab.
• It stiffen the slab and hence reduce deflection.
FIG 1.3 FLAT SLAB WITH COLUMN
10. 4
CHAPTER 2
Advantages of Flat Slabs
It is recognized that Flat Slabs without drop panels can be built at a very fast pace as the
framework of structure is simplified and diminished. Also, speedy turn-around can be achieved
using an arrangement using early striking and flying systems.
Flat slab construction can deeply reduce floor-to –floor height especially in the absence of false
ceiling as flat slab construction does act as limiting factor on the placement of horizontal
services and partitions. This can prove gainful in case of lower building height, decreased
cladding expense and pre-fabricated services.
In case the client plans changes in the interior and wants to use the accommodation to suit the
need, flat slab construction is the perfect choice as it offers that flexibility to the owner. This
flexibility is possible due to the use of square lattice and absence of beam that makes
channelling of services and allocation of partitions difficult.
2.1 Thickness of flat slab
Thickness of flat slab is another very attractive benefit because thin slab provides the advantage
of increased floor to ceiling height and lower cladding cost for the owner. However, there is
profound lower limit to thickness of slab because extra reinforcements are needed to tackle
design issues. Besides this, added margin must be provided to facilitate architectural alterations
at later stages.
2.2 Types of Flat Slab Design
Multitudes of process and methods are involved in designing flat slabs and evaluating these
slabs in flexures. Some of these methods are as following:
• The empirical method.
• The sub-frame method.
• The yield line method.
• Finite –element analysis.
11. 5
CHAPTER 3
1. Benefits of flat slab
❖ Flexibility in room layout
• Introduce partition walls anywhere required • Change the size of room layout • Omit
false ceiling
❖ Saving in building height.
• Lower storey height will reduce building weight • approx. saves 10% in vertical
members • reduce foundation load.
❖ Shorter construction time
• flat plate design will facilitate the use of big table formwork to increase productivity.
❖ Ease of installation of M&E services
• All M & E services can be mounted directly on the underside of the slab instead of
bending them to avoid the beams.
• Avoids hacking through beams.
12. 6
CHAPTER 4
2. NEED OF FLAT SLABS
• When plain ceiling is required.
• When floor to ceiling height is very less.
• Where deep beam provides obstruction and reduces headroom.
• Where beams may obstruct movement of goods. eg. Godowns & Store rooms.
FIG 4.1 DEFLECTION DIAGRAMS
13. 7
Engineers very often use flat slabs in the building because of its advantages over reinforced
concrete floor system (7 Reasons Why the Flat Slab with Drop Panels is Widely Used). Some
of the advantages are:
1. Flexibility in room layout – where the installation of the partition walls can be done
anywhere.
2. Easier reinforcement placement – detailing of reinforcement on flat slab is simple, and
easier to place.
3. Ease framework installation- in flat slab can be used a big table framework.
4. Building height can be reduced- As no beam is used, floor height can be reduced and
consequently the building height will be reduced.
5. Less construction time needed because of the big table frameworks used.
6. Prefabricated welded mesh are standard sizes, need less installation time and better
quality control.
7. The Auto sprinkler is easier.
14. 8
CHAPTER 5
3. CODE REGULATIONS
• Column strip
Width of column strip 0.25L2 on each side but not greater than 0.25L1.
• Middle strip
Middle strip means a design strip bounded by column strip on all the four sides.
• Drop
The drop when provided shall be rectangular in plan, and have a length in each direction
not less than one third of the panel length in that direction.Thickness of Drop shall not
be less than ¼ of thickness of slab.
• Thickness of slab
The slabs with drop conforming to above clause, l/d ratio given in IS 456 2000 ,
Cl.23.2 shall be applied directly ; otherwise ratio multiplied by 0.9.The minimum
thickness of slab shall be 125 mm.
• Shear in flat slab
The critical section for shear shall be at a distance d/2 from the periphery of the
column /capital or drop pane. And permissible shear stress = k uc.
• Slab reinforcement
Spacing shall not be more than 2 times slab thickness.
3.1METHODS OF ANALYSIS
1.DIRECT DESIGN METHOD.
2.EQUIVALENT FRAME METHOD.
5.1.1 DIRECT DESIGN METHOD
1. LIMITATIONS
• Minimum three continuous span.
• Aspect ratio (Ly/Lx) shall not be greater than 2.
• The successive span lengths in each direction shall not differ by more than
one third of the longer span.
• The end span may be shorter but not longer than interior span.
• Design live load shall not exceed three times the design dead load.
15. 9
2. DESIGN MOMENTS
• The total bending moment in each direction is equal to Mo=(W.Ln)/8.
• Total negative design moment (Mn)= 0.65Mo.
I. Negative moment taken by column strip= 0.75Mn.
II. Negative moment taken by middle strip= 0.25Mn.
• Total positive design moment(Mp)= 0.35Mo
.
I. Positive moment taken by column strip= 0.6Mp.
II. Positive moment taken by middle strip= 0.4Mp.
5.1.2 EQUIVALENT FRAME METHOD
ASSUMPTIONS
• The structure shall be considered to be made up of equivalent frames consist of
two successive columns and slab between them.
• Each frame may be analysed floor wise.
• Relative stiffness of members may be determined by moment of inertia of members
considering gross c/s of the concrete alone.
• Variation of moment of inertia due to thickness of drop may be ignored.
DESIGN MOMENTS
FIG 5.1 DESIGN MOMENT
16. 10
CHAPTER 6
6. DESIGN STEPS
I. Trial depth.
II. Loading calculations.
III. Provision of drop and column capital.
IV. Stiffness and Distribution factors.
V. Fixed end moments and moment distribution table.
VI. Distribution of moments across the panel.
VII. Check for Depth against flexure.
VIII. Determination of area of steel.
IX. Check for deflection.
X. Check for shear.
6.1. ADVANTAGES
• It provides larger clear ceiling height.
• It is ideally suitable for Godowns and Store rooms.
• The construction is simple and economical.
• The plain ceiling gives an attractive andpleasing appearance.
• Acoustical treatment is easy.
6.2. DISADVANTAGES
I. The stiffness of the structure comprising offlat slab and column is slight less.
II. These are suitable for only low to mediumrise buildings.
III. In broad sense, these are economical for spansup to 10 meters.
IV. Serviceability problems may arise withexcessive long term deflection.
17. 11
CHAPTER 7
7.0 Design of flat slabs by IS: 456
The term flat slab means a reinforced concrete slab with or without drops, supported generally
without beams, by columns with or without flared column heads (see Fig. 12). A flat slab may
be solid slab or may have recesses formed on the so fit so that the soffit comprises a series of
ribs in two directions. The recesses may be formed by removable or permanent filler blocks.
Components of flat slab design:
a) Column strip :Column strip means a design strip having a width of 0.25 I,, but not greater
than 0.25 1, on each side of the column centre-line, where I, is the span in the direction moments
are being determined, measured centre to centre of supports and 1, is the -span transverse to 1,,
measured centre to centre of supports.
b) Middle strip :Middle strip means a design strip bounded on each of its opposite sides by
the column strip.
c) Panel: Panel means that part of a slab bounded on-each of its four sides by the centre -line
of a Column or centre-lines of adjacent-spans
Division into column and middle strip along:
Longer span Shorter span
L1 =6.6 m , L2 =5.6 m L1 =5.6 m , L2 =6.6 m
( i ) column strip ( i ) column strip
= 0.25 L2 = 1.4 m = 0.25 L2 = 1.65 m
But not greater than 0.25 L1 = 1.65 m But not greater than 0.25 L1 = 1.4 m
(ii) Middle strip (ii) Middle strip
= 5.6 – (1.4+1.4) = 2.8 m = 6.6 – (1.4+1.4) = 3.8 m
18. 12
The drops when provided shall be rectangular in plan, and have a length in each direction
not less than one- third of the panel length in that direction. For exterior panels, the width of
drops at right angles to the non- continuous edge and measured from the centre -line of the
columns shall be equal to one -half the width of drop for interior panels.
Since the span is large it is desirable to provide drop.
Drop dimensions along:
L1 =6.6 m , L2 =5.6 m L1 =5.6 m , L2 =6.6 m
Not less than L1 /3 = 2.2 m Not less than L1 /3 = 1.866 m
Hence provide a drop of size 2.2 x 2.2 m i.e. in column strip width.
e) column head :Where column heads are provided, that portion of a column head which
lies with in the largest right circular cone or pyramid that has a vertex angle of 90”and can
be included entirely within the outlines
of the column and the column head, shall be considered for design purposes
Column head dimension along:
Adopting the diameter of column head = 1.30 m =1300 mm
f) Depth of flat slab:
The thickness of the flat slab up to spans of 10 m shall be generally controlled by
considerations of span ( L ) to effective depth ( d ) ratios given as below:
Cantilever 7
Simply supported 20
Continuous 26
For slabs with drops, span to effective depth ratios gi ven above shall be applied directly;
otherwise the span to effective depth ratios in accordance with above shall be multiplied by
Longer span Shorter span
Longer Span Shorter Span
L1 =6.6 m , L2 =5.6 m L1 =5.6 m , L2 =6.6 m
Not greater than L1 /4 = 1.65 m Not greater than L1 /4 = 1.4 m
19. 13
0.9. For this purpose, the longer span of the panel shall be considered. The minimum thickness
of slab shall be 125 mm.
Depth of flat slab:
Considering the flat slab as a continuous slab over a span not exceeding 10 m
Taking effective depth of 25mm
Overall depth D = 260 +25 = 285 mm > 125 mm (minimum slab thickness as per IS: 456)
It is safe to provide depth of 285 mm.
g) Estimation of load acting on the slab:
Dead load acting on the slab = 0.285 x 25 = 6.25 2 KN/m^2 =Wd1
Floor finishes etc. load on slab = 1.45 2 KN/m^2 = Wd2
Live load on slab = 7.75 2 KN/m^2 = Wl
Total dead load = Wd1 + Wd 2 =7.7 2 KN/m^2 =Wd
The design live load shall not exceed three times the design dead load.
Check:
Wl/Wd =7.75/7.7 = 1.006<3
OK
Total design load = Wd +Wl = 15.45 KN/m^2
h) Total Design Moment for a Span
20. 14
The absolute sum of the positive and average and is given by negative bending moments in
each
direction shall be taken as:
Mo = (W*Ln /8)
Mo = total moment.
W = design load on an area L1 and L2
Ln = clear span extending from face to face of columns, capitals, brackets or walls, but not less
than 0.65 L1
L1 = length of span in the direction of M0 .
L2= length of span transverse toL1
Circular supports shall be treated as square supports havi ng the same area.
Equivalent side of the column head having the same area:
a = (3.14*d^2 / 4) = 1.152m
Clear span along long span = Ln = 5.448m> 4.29
(Should not be less than 0.65 L1 )
OK
Clear span along long span =Ln = 4.44m> 3.64
(Should not be less than 0.65 L1)
OK
21. 15
CONCLUSION
By studying results obtained after analysis, design and cost comparison with normal beam
slab construction, we can conclude that, by constructing flat slab economy can be achieved
up to great extent for medium span and low to medium class superimposed loads.
But flat slab construction may prove to be uneconomical for span larger than 10 mts. and high
intensity superimposed loads. So it is wise to construct flat slab instead of normal slab-beam
construction, considering various aspects mentioned in the design to achieve economy as well
as functional requirements with aesthetic view.
22. 16
REFERENCES
1. Dr. V.L. Shah, Late Dr. S.R. Karve, Limit State Theory And Design Of
Reinforced Concrete, Structures Publications, Edition-Oct-2002.
2. Shushil Kumar, Design Of Reinforced Concrete Structure.
3. Indian standard 456-2000.
4. Indian standard 875-part(1).
5. Indian standard 875-part(2).