Introcduction slab in which the deflected surface is predominantly cylindrical termed as one way slabs spanning in the direction of curvature. One way slab is a slab which is supported by beams on the two opposite sides to carry the load along one direction. Whats the difference between one way continuous slab and two. 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. One way and two way slabs one way slabs transfer the imposed loads in one direction only. Ultimate behavior of oneway spanning slab linear elastic analysis methods such as moment distribution are linear elastic methods. Here ratio of longer span of slab to the shorter span of slab is greater than 2. I hope you liked this video if yes please subscribe to my channel. Pdf oneway shear strength of thick slabs and wide beams. One way slab being supported on two opposite sides only leads to the structural action in single direction. Chapter 3 design of rectangular beams and oneway slabs 12. It is supported by the beam from two opposite sides parallel. The slab is supported on beams of size 225 x 500 mm spaced at 4.
Design of reinforced concrete structures ii two way slabs 1 1. Design of continuous one way slabs checks, detailing. Define the term slab, one way slab, two way slab, shrinkage and temperature reinforcement, main reinforcement. Design procedure steps for one way slab slab design steps. Design of a oneway slab step1 selection of thickness, h aci 318 11building code requirements for structural concrete by american concrete institute, aci. In multistory buildings for instance, for each floor, columns are cast first and the floor system slab and beams is cast after. The basic design procedure of a two way slab system has five steps. Design of slab examples and tutorials by sharifah maszura syed mohsin example 2. Pdf design calculation design of one way slab slab s1 span. Lecture series on design of reinforced concrete structures by prof. Reinforced concrete continuity rc structures cannot be erected in a single pour of concrete. Bending will take place in the two directions in a dishlike fo. The design bending moments are zero at discontinuous ends, negative at continuous ends and positive at midspans. One way spanning slabs should be treated as beams of unit width and chapter 2 should be followed except for minimum shear reinforcement.
Slabs are usually used in floor and roof construction. Slab design in case of oneway slabs, the reinforcement against bending is estimated only for short direction. Reinforced concrete design 1 design of slab examples. One way simplysupported and continuous solid slab bending.
Pdf ce 370 reinforced concretei continuous beams and one. Reinforced concrete slab design and detailing guidelines for depth of slab, loads on slab, reinforcement guide for one way and two way slabs as per is 456. Analysis and design of slabs one way civil engineers pk. Oneway and twoway slabs oneway slabs transfer the imposed loads in one direction only. Powered by the equivalent frame method of analysis and design per latest american aci 31814 and canadian csa a23. For one way slab, main reinforcement is computed by a formula in limit state design that is determined by comparing compressive force as well as tensile forces. Design of reinforced concrete structure one way slab presented by md. Although the major reinforcement in one way slab span is in the short direction, yet at the corner, the moment is actual supported by beams at both directions. Following are the rcc slab design and detailing guidelines.
The ratio of the longer span to the shorter span is greater than or equal to 2 is known as the one way slab. You can design a single span simply supported, fixed or cantilever or many continuous spans. Part two is an exampleintensive course, with key concepts introduced along the way. D mm d 105 mm loads on slab self weight of slab 3. Download as ppt, pdf, txt or read online from scribd.
Slab is a common term used to describe the structural elements such as floors and roofs where the thickness of the element is very small compared to the length and. Chapter 7 analysis of continuous oneway slabs blogger. Rectangular beams and one way slabs page 2 of 9 two methods. Dec 31, 20 in the previous chapters we saw the analysis and design of simply supported beams and slabs. While the basic expression for one way shear in aci 31805 is the same for narrow beams, wide beams, and slabs, an engineer is permitted to design to higher shear stresses in the latter two cases. Distribute moments transverse at critical sections to column and middlestrip and if. The behavior and the reinforcement of a one way slab connected to a cantilever are described below. For 1m slab width, moment, shear force, oneway continuous slab for continuous slab, moment and shear force can be obtained from table 3.
Application of one way slab provides useful flat surface one way slab may be used when there is architectural limitations it is the simplest form of slab design main reinforcement placing is one way, so there is a little congestion than two way slab 29. Continuous oneway solid slab concrete structures eurocode. The slab is supported on 200 mm wide loadbearing block walls at 6000 mm centres. These are idealised as continuous beam of unit width. Design of reinforced concrete structures ii twoway slabs. According to the way loads are transferred to supporting beams and columns, slabs are classified into two types. More detailed advice on determining design li fe,actions, material properties, methods of analysi s. Design of slab examples and tutorials by sharifah maszura syed mohsin.
Oneway and twoway slabs oneway slabs transfer the imposed. Design of oneway slabs check if it is oneway slab system if clear span in one direction, l1, is greater than or equal to two times the clear span in other direction, l2, then it is. One way slab design procedure with example design of one. One way slab reinforcement details daily civil engineering. In this video i have explained how to design one way continuous slabs as per is code method.
Design of one way slabs as per is 456 worked step by step. Chapter 3 design of rectangular beams and oneway slabs. Here are the steps for the design procedure for one way slab in steps. Oneway simply supported slab analysis and design of the slab similar to design of simply supported beam as indicate in the previous chapter. The continuous beam along grid 3 is selected to demonstrate the analysis and design of continuous tbeams structural analysis, flexural design, shear design, deflection checks and the results of hand calculations are then compared with numerical analysis results obtained from the spbeam engineering software program. One way simplysupported and continuous solid slab free download as powerpoint presentation. Crosssections can include a combination of rectangular, i, t and lsections, and spans can have constant or tapered sections. If moment and shear coefficients are used, computations should be based on clear spans. One way slabs are such slabs in which the loads are shared only by the shorter direction of the slab.
Reinforced concrete design 1 design of slab examples and. 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. Design and detailing of reinforced concrete beams and slabs. That is, the load factor at which the uls moment equals the moment capacity. One way continuous slab the slabs spanning in one direction and continuous over supports are called one way continuous slabs. If the first slab is a two way slab, both the behavior and the reinforcement rules are proportionate.
Jul 02, 2015 one way concrete slab design part 1 concept explained and minimum slab thickness canadian code duration. Slabs are plate elements forming floors, roofs in buildings, and as. When we complete this discussion about continuous one way slabs, we will be able to do the analysis of continuous beams also. Jul 02, 2010 lecture series on design of reinforced concrete structures by prof. To see their result for this slab we will find the load factor. Chapter 18 concrete slab structures january 2019 183 18. Calculate factored moment and shear force by considering the onemeter width of the slab. Bending will take place in the two directions in a dishlike form. Fundamentals of posttensioned concrete design for buildings. These loads shall be applicable for the design of buildings design of reinforced concrete shear wall. Determine moments at critical sections in each direction, normally the negative moments at supports and positive moment near midspan. Design of cantilever slab one way slab design spreadsheet according to aci 3 sep 20 the value of 23 is appropriate for two way spanning slab if it is continuous over one long side.
Based on the stiffness requirement assume suitable depth and calculate the effective span. Generally, thickness of slab is sufficient to resist shear stresses, so there is no need for extra shear reinforcement. Continuous one way slab figure 1 shows a clear area of 12 m x 8. Part three continues with the study of two way, posttensioned slab systems, including a complete design example using the equivalent frame concept. Reinforced concrete slab design and detailing guide is456. For slabs of uniform section which support substantially udl over three or more spans which do not differ by. 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. Feb 24, 2019 a 175 mm thick continuous slab is required to support screed, finishes, an office variable action of 2. 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. For those who do not know what are the des ign requirements of a slab. Slab with reinforcement with yield stress, f y, exceeds 60,000 psi measured at a yield strain of 0. One way slabs are normally designed with tensile steel ratios well below the maximum. Allowable stress design or working stress design wsd 2.
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