The design procedure for a uniformly loaded one way reinforced slab can be divided in the following steps. Bending will take place in the two directions in a dishlike fo. This example goes through the design of a simplysupported oneway slab on beams. Two way slabs have two way bending unlike one way slab. Oneway simply supported slab analysis and design of the slab similar to design of simply supported beam as indicate in the previous chapter. Ankit gupta, marketing manager at intelligrape software 2015present. The following example illustrates the example building. Determine moments at critical sections in each direction, normally the negative moments at supports and positive moment near midspan. The results of this analysis are compared with the results of the finite element method by sap program. Slab design in case of one way slabs, the reinforcement against bending is estimated only for short direction. A single slab with one way reinforcement rebars will be analyzed with rcsolver. Two way concrete floor slab with beams design and detailing design the slab system shown in figure 1 for an intermediate floor where the story height 12 ft, column crosssectional dimensions 18 in. Rectangular beams and one way slabs page 2 of 9 two methods. Introduction concrete slabs on grade are a very common type of concrete construction.
Slab design is comparatively easy when compared with the design of other elements. A 175 mm thick continuous slab is required to support screed, finishes, an office variable action of 2. Step 2 design forces draw panel of slab and indicate maximum design moments, shears and in. One way slabs are such slabs in which the loads are shared only by the shorter direction of the slab. Pt designer design of posttensioned concrete floors. Design of reinforced concrete structure one way slab presented by md. Analysis and design of slabs two way two way edge supported slabs two way slabs. Mar 07, 2017 rcc slab design depends on the on the dimensions of the slab after which the slab is termed as a oneway slab or a twoway slab in the design of rcc structures, column design and beam design are to be done before we start with rcc slab design basic rules followed in the design of simply supported slab thickness of slab. Bridge approach slab analysis and design incorporating elastic soil support presented by.
A reinforced concrete slab is built integrally with its supports and consists of equal span of 15 ft. The output of the program for the slab in the example is shown in the following pages. Pdf design calculation design of one way slab slab s1. Design of a two way rcc slab structural engineering forum.
Before going to this topic, please read it there are two types of slab classification based on the direction of bending occurs in these slabs. Bending will take place in the two directions in a dishlike form. More detailed advice on determining design li fe,actions, material properties, methods of analysi s. Learn to design reinforced concrete one way slabs through. For one way slabs the load from slab is split between the beams supporting the slab along. In this article, it is assumed that slab thickness is determine but calculation of column and middle strips is explained in the following section. The load is transferred from slab to beams by distributing the load over the beam. Lecture series on design of reinforced concrete structures by prof. Determine moments at critical sections in each direction, normally the negative. Define the term slab, one way slab, two way slab, shrinkage and temperature reinforcement, main reinforcement. Two way flat plate concrete floor system analysis and design the concrete floor slab system shown below is for an intermediate floor to be designed considering partition weight 20 psf, and unfactored live load 40 psf. All of the concepts of this subject are taught entirely through actual step by step. Ribbed slabs one way joists introducing voids to the soffit of a slab reduces dead weight and increases the efficiency of the concrete section. Choose design method equivalent frame method use elastic frame analysis to.
D mm d 105 mm loads on slab self weight of slab 3. Footings example 1design of a square spread footing of a sevenstory building. Chapter 3 design of rectangular beams and oneway slabs 12. Advisory board committee on residential slabsonground. One way spanning slabs should be treated as beams of unit width and chapter 2 should be followed except for minimum shear reinforcement. Fundamentals of posttensioned concrete design for buildings part one a suncam online continuing. The one way shear capacity for the ribbed slab portions shown is permitted to be increased by 10%. One way and two way slabs one way slabs transfer the imposed loads in one direction only. Rectangular beams and oneway slabs page 3 of 9 design of rectangular beams and oneway slabs continued a. The construction and design of concrete slabs on grade. Part two is an example intensive course, with key concepts introduced along. Welcome to the learn to design reinforced concrete one way slabs through examples course by engineering examples. One way slab being supported on two opposite sides only leads to the structural action in single direction.
One way slab is the most basic and common type of slab. Oneway and twoway slabs oneway slabs transfer the imposed loads in one direction only. One way slab supported on beams the objective of this tutorial is to demonstrate the stepbystep procedure of adapt pt to analyze and design a posttensioned continuous slab supported on parallel beams or walls. Element simply supported one end continuous both end continuous cantilever one way slabs l20 l24 l28 l10 where l is the span length in the direction of bending. Two way joist waffle slab design approach and methodology two way joist slab often called two way ribbed slab or waffle slab is an economical floor system when the spans are. Analysis and design of slabs two way civil engineers pk. This calculation is intended to show in detail the provisions of designing a slab to eurocode 2 using essentially the same slab as used in example 3. Comparison of one way and two way slab behavior one way slabs carry load in one direction. This course covers the analysis and design of reinforced concrete one way slabs using aci code 31811. One important thing is that in the output, the word top and bottom refer to the local top and bottom surfaces of the individual elements, and not in the global axis sense.
General overview of posttensioned concrete design instructor. Type of slab is strongly affected by architectural and construction considerations. Plan view of floor system assume partitions will not be damaged by deflections. Hb1011 314 design aids american concrete institute. Twoway concrete slab with beams spanning between supports. Allowable stress design or working stress design wsd 2. After completion of this course, you are expected to be able to design the two types of rc beams. Beams of width and depth are provided on all column lines. Analysis and design of one way and two way slab in staad. A single slab with oneway reinforcement rebars will be analyzed with rcsolver. This course design of reinforced concrete slab gives you detailed understanding, explanations and procedures for the design of rc slabs. One way and two way slab design aspect the slab provides a horizontal surface and is usually supported by columns,beams or walls. The construction and design of concrete slabs on grade d.
Strength design or ultimatestrength design usd strength design or ultimatestrength design usd with strength design method, the working dead load dl and live load ll are. Distribute moments transverse at critical sections to column and middlestrip and if. In case of one ways slabs, the aci approximate analysis is applicable to one way slab system where a one way slab is continuous with a one way slab. Download file pdf flat slab manual design bs flat slab manual design bs flat slab design example part 1 how to design a flat slab, step by step explained in this video. What is the different between the one way slab and two way slab. A slightly deeper section is required but these stiffer floors facilitate longer spans and provision of holes. A six storey building for a commercial complex has plan dimensions as shown in figure 1. Flat plate concrete floor system does not use beams between columns or. According to the way loads are transferred to supporting beams and columns, slabs are classified into two types. Mathematical structural analysis of one way ribbed slabs was introduced in this paper.
Jan 15, 2017 one way slabs are those supported continuously on the two opposite sides so that the load sare carried along one direction only. Shear strength of two way slabs shear failure occurs when inclined cracks form due to flexural and shearing stresses. Next go to concrete design commands design slab element. Here ratio of longer span of slab to the shorter span of slab is greater than 2. One way and two way slab design aspect online civilforum. Engineering force ltd project 54 russell road, london job ref. Design of reinforced concrete structures ii two way slabs 1 1. In sap program, the model has been divided to frame elements to represent ribs and beams and shell elements to represent the slab and solid part. I have developed a microssoft excel software for design of a two way rcc slab.
Design calculation design of one way slab slab s1 span of one way slab l 2m section provided d mm d 105 mm loads on slab self weight of slab 3. Two way slab design by direct design method as per aci 31811. Reinforced concrete design 1 design of slab examples and. Design the concrete slab and calculate the required tensile reinforcement for. All of the concepts of this subject are taught entirely through actual step by step examples. Generally, there are two types of slab which are one way and two way slabs.
Beams and one way slabs how to design concrete structures using eurocode 2 design procedure a procedure for carrying out the det ailed desi gn of slabs assumes that the slab thickness has previously been determined during conceptual design. Firstly, one has to check if the design shear force v d is smaller than the maximum punching strength v rd,max. For flat plates and slabs the column connections can vary between. Design procedure steps for one way slab slab design steps. You should look at the bar diameter and spacing in the table displayed next to the graphical viewer or at fi16 400 mm on the description of the reinforcement bar in this zone instead as this is the actual area of the provided reinforcement. Oneway and twoway slabs university of asia pacific. Design examples look at example 7 design of a flat plate floor without spandrel beams direct design method look at example 9 design of a two way slab with beams in both directions. The program covers wide range of two way slab systems and can be used for more complex slab layouts. Whatever may be the width of the slabs it should always be designed for a width of equal to one metre and the same design should be adopted for the rest of the slab. Analysis and design of slabs, one way slabs, online free slab design, design of slabs one way, free slab design online, design procedure for one way slab. The ratio of longer span l to shorter span b is equal or greater than 2, considered as one way slab because this slab will bend in one direction i. Ec2 webinar autumn 2016 lecture 52 designing for shear in slabs when shear reinforcement is not required e. Slab resting on walls or sufficiently deep and rigid beams on all sides. Chapter 3 design of rectangular beams and oneway slabs.
Generally, thickness of slab is sufficient to resist shear stresses, so there is. Design of oneway reinforced concrete slabs class notes and examplepage 1 of 6 notes on designing oneway slabs aci 318 ch. One way slab is a slab which is supported by beams on the two opposite sides to carry the load along one direction. If slab is supported on all four sides and r shorter side longer side one way slab. Design manual to bs8110 outline of the bs8110 design process outline of the bs8110 design process calculate vc concrete shear capacity without reinforcement the design process for the now withdrawn bs8110 design standard works slightly differently to that used in. Designs done by this method should be economical yet give quite satisfactory results with a minimum of deflection. A 2 2area 2 a c 2 2 posttensioned concrete design table 11 list of symbols used in the aci 31808 code cp area enclosed by the outside perimeter of the section, in a g gross area of concrete, in a 2 l total area of longitudinal reinforcement to resist torsion, in a o area enclosed by the shear flow path, sqin a oh area enclosed by the centerline of the outermost closed. Slab design reading assignment chapter 9 of text and, chapter of aci31802. Shades in the roofing system cantilever slab of stairs. One way slab has two types namely simply supported slab and one way continuous slab. Fundamentals of posttensioned concrete design for buildings. Nov 27, 20 one way slab design criteria with design example according to aci code slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Dhang, department of civil engineering, iit kharagpur.
The first stage of the design is finding the bending moment of the slab panels. The program is developed around the robust computational core of two popular programs ptdata. The pca computer program pcaslab can be used to expedite the design of different slab systems. Want to make money offering email marketing to your clients.
Guide to design of simply supported slabs design of rcc. They may be supported on two opposite sides only fig. Fundamentals of posttensioned concrete design for buildings part one. Oneway and twoway slabs oneway slabs transfer the imposed. Pt designer is a computer program for the design and analysis of linear posttensioned concrete floor systems. Continuous oneway solid slab concrete structures eurocode. Design of slab examples and tutorials by sharifah maszura syed mohsin. If you continue browsing the site, you agree to the use of cookies on this website.
What is the formula for taking load from two way slab for beam design. Members of aci committee 314, simplified design of concrete buildings. The coefficient method may be the simplest, easiest and the quickest approach for the design of two way slab supported by edge beam on all slab sides. Design a oneway slab for an exterior bay of a multistory office building using the information specified below. For those who do not know what are the des ign requirements of a slab. Slab consists of two types which are one way slab and two way slabs. The service live load is 100 psf and 4000 psi concrete is specified for use with steel with a yield stress equal to 60000 psi. Two way slab design by direct design method as per aci 31811, step by step procedure and limitations of direct design method for two way slab is presented.
Twoway joist waffle slab design approach and methodology. Use a spreadsheet to design each section and show your results with a sketch elevation view. Rc slab design ec2 worked example shear and deflection checks duration. While two way slabs also consist of two types namely simply. Example design of two way edgesupported solid slab. One way slab design procedure with example design of one. Analysis and design of slabs one way civil engineers pk. This method was provided in the american concrete institute aci in 1963 to design two way slabs. Simplified design to bs 5400 bridge design to the eurocodes in part d. Designing for shear in slabs including punching shear detailing solid slabs flat slab design includes flexure worked example exercise punching shear.
Here are the steps for the design procedure for one way slab in steps. Assume partitions cannot be damaged by deflections. Floor slabs can range from a simple residential basement slab to a heavyduty industrial floor. For 1m slab width, moment, shear force, oneway continuous slab for continuous slab, moment and shear force can be obtained from table 3.
Introcduction slab in which the deflected surface is predominantly cylindrical termed as one way slabs spanning in the direction of curvature. For consistency, many of the numerical examples are based on a fictitious sevenstory reinforced concrete building. I am submitting it to you and i want students or professional engineers to download it and use it for their studies or projects. Asce, secb course content slab on grades construction. The two classifications are one way slab and two way slab. Depending on the boundary condition and the properties of the slabs, methods of finding bending moment is expressed in the bs 8110 part 01 as follows. Before the start of two way slab design, slab depth should be determined in addition to specify column strips and middle strips. Footings example 1design of a square spread footing of a seven. A monolithic reinforced concrete floor is to be composed of rectangular bays measuring, as shown. Ce 433, summer 20 slab design example 1 5 design a one. In the output file you will get the details reinforcements of the slab.
A typical sixspan, one way slab supported on beams,as occurs in parking structures is selected. Master of science and hereby certify that, in their opinion, it is worthy of acceptance. Step 2 design forces draw panel of slab and indicate maximum design moments, shears and in plane loads, if any, per unit width of slab. One way solid slabs are designed as a number of independent 1 ft or 12 wide strips which span in the short direction and supported on crossing beams.
Design of reinforced concrete structures ii twoway slabs. The reinforced concrete design handbook now provides dozens of design examples of various reinforced concrete members, such as one and two way slabs, beams, columns, walls, diaphragms, footings, and retaining walls. Effective span of slab shall be lesser of the two 1. Slab with reinforcement with yield stress, f y, exceeds 60,000 psi measured at a yield strain of 0.
For 1m slab width, moment, shear force, one way continuous slab for continuous slab, moment and shear force can be obtained from table 3. The building is located in seismic zone iii on a site with medium soil. There are some basic steps which we generally do while designing theoretically some steps are rcc slab design guidelines. Net, which many engineers have come to trust over the years for its accuracy and flexibility. One way simply supported slab analysis and design of the slab similar to design of simply supported beam as indicate in the previous chapter. Jul 10, 2017 this example goes through the design of a simplysupported oneway slab on beams. First and foremost i would like to say very detailed explanation you have got there, thanks. Slabs are usually used in floor and roof construction. The direction in which the load is carried in one way slab is called the span.
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