Fatal parking garage collapse at the tropicana casino resort. Slabs are constructed to provide flat surfaces, usually horizontal, in building floors, roofs, bridges, and other types of structures. One way and twoway slabs one way slabs transfer the imposed loads in one direction only. Summary of bill of quantities civil works bar bending schedule.
Oneway and twoway slabs oneway slabs transfer the imposed loads in one direction only. However, it should be known that the coefficient method is still applied for twoway slabs. Flat slab system is an important division of concrete floor system. Hidden or drop beams can be used with this system depending on their spans. Flat slab analysis, design and detailing pdf civil engineering. Oneway and twoway slabs university of asia pacific. Introcduction slab in which the deflected surface is predominantly cylindrical termed as oneway slabs spanning in the direction of curvature. Plan view of floor system assume partitions will not be damaged by deflections. 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. Jul 10, 2017 this example goes through the design of a simplysupported oneway slab on beams.
A reinforced concrete slab is built integrally with its supports and consists of equal span of 15 ft. The two classifications are oneway slab and twoway slab. There are several methods by which two way slabs can be designed. The design of composite slabs and beams is discussed in detail in relation to the eurocodes and bs 5950. The following example illustrates the example building. Twoway concrete slab with beams spanning between supports. Design of a two way slabs for punching shear resistance. Here, we have tried to gather various reading materials available in the web about flat slab floor system in one place. This condition occur when the slabs are connected monolithically with support. Two way slab design by direct design method as per aci 31811. Design of one way reinforced concrete slabs class notes and example notes on. For those who do not know what are the des ign requirements of a slab. Slabs are usually used in floor and roof construction. How to design a two way slab free download as powerpoint presentation.
Twoway slab deflection calculation serviceability comparison of twoway slab analysis and design methods. This is to simplify the calculation of moment of inertia of the section. The following example illustrates the design methods presented in the pca book simplified design reinforced concrete buildings of moderate size and height third edition. Look at example 7 design of a flat plate floor without spandrel beams direct design method look at example 9 design of a twoway slab with beams in both directions. Design the slab following the provisions of the aci code.
Introcduction slab in which the deflected surface is predominantly cylindrical termed as one way slabs spanning in the direction of curvature. Reinforced concrete design 1 design of slab examples. Design of reinforced concrete components of a house. 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. The first aa solution is a twoway concrete solid slab with depth3 h 18 cm supported by 0,25. Beams of width and depth are provided on all column lines. Twoway restrained slab if the slabs consist more than one panel or corner of the slab are prevent against lifting it is define as twoway restrained slab. Reinforced concrete design 1 design of slab examples and. In this article, it is assumed that slab thickness is determine but calculation of. Design of slab examples and tutorials by sharifah maszura syed mohsin example 1. Twoway flat plate concrete floor system design structurepoint. Pdf the paper presents the cost optimization of reinforced concrete simply supported oneway slabs under uniformly distributed load with the nonlinear. Ce 433, fall 2006 slab design example 1 6 design a oneway slab for an exterior bay of a multistory office building using the information specified below. Reinforced concrete design to bs8110 structural design 1.
The direct design method of analysing a twoway slab is not recommended for prestressed. Framing dead load selfweight superrimposed dead load 25 psf partitions, me, misc. Unless otherwise noted, all referenced table, figure, and equation. Frame analysis also provides a convenient way for generating input for this program. Rectangular beams and one way slabs page 2 of 9 two methods. Reinforced concrete slab design and detailing guide is456. Use the aci 318 direct design method to design an interior bay of a flat plate slab system of multi bay building.
Twoway slab analysis and design using equivalent frame method efm. Shear strength of twoway slabs shear failure occurs when inclined. Design of a two way rcc slab structural engineering forum. Pdf analysis of two way ribbed and waffle slabs with. Contains all design checks required by the american concrete institute code and all the conditions that must be met during the design process. Tn342 design example 2way mondada 093090 adapt corporation. Generally, there are two types of slab which are one way and two way slabs. The dimensions of an interior bay are shown in figure 1. The slab may be supported by walls, by reinforced concrete beams usually cast monolithically with the slab, by s. One way and two way slabs one way slabs transfer the imposed loads in one direction only. It shows possible solutions of two way prestressed floors depending on different factors. A six storey building for a commercial complex has plan dimensions as shown in figure 1. Determine moments at critical sections in each direction, normally the negative moments at supports and positive moment near midspan. Reinforced concrete slab design and detailing guidelines for depth of slab, loads on slab, reinforcement guide for oneway and twoway slabs as per is 456.
Deflection calculations from nilson and nawy the deflection of a uniformly loaded flat plate, flat slab, or twoway slab supported by beams on column lines can be calculated by an equivalent frame method that corresponds with the method for moment analysis. One way slab design procedure with example design of one. Slabs and flat slabs lecture 5 19 th october 2016 contents lecture 5 designing for shear in slabs including punching shear detailing solid slabs flat slab design includes flexure worked example exercise punching shear. In lieu of detailed calculation for deflections, csa a23. 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. Now calculate bar bending schedule for two way slab.
Design of slab two way excel sheet design spreadsheets the specified design strength of the concrete, is 25 mpa and the specified yield strength of the reinforcement, fy, is 400 mpa. A g j way meng, ceng, mice t c cosgrove bsc, msc, dic, miei, ceng, mistructe. Jul 22, 2015 design of two way ribbed slab 18 x 25 m clear span 1. Accurately determining the moments on a twoway slab is typically accomplished by finite element computer analysis. Determine moments at critical sections in each direction, normally the negative. All methods are viable provided that the safety and serviceability of the elements are within the acceptable limits. Flat slab analysis, design and detailing pdf flat slab system is an important division of concrete floor system. Design of reinforced concrete structures ii twoway slabs. In addition to general ultimate and serviceability limit state design issues, practical design considerations such as the formation of holes in the slab, support details, fire protection, and attachments to the slab are discussed.
A civil engineer must know all the aspects regarding the flat floor system. Mass and volume are the two types of batching for measuring cement, sand, coarse aggregates, admixtures and water. Example design of two way edgesupported solid slab. The file extension pdf and ranks to the documents category. Allowable stress design or working stress design wsd 2. Slab resting on walls or sufficiently deep and rigid beams on all sides. Flat plate concrete floor system does not use beams between columns or. Twoway slab design equivalent frame method efm moment distribution column stripbeam. Design of reinforced concrete structure one way slab presented by md. Structural design for residential construction cynthia chabot, p. The beam could be considered a thickened slab at the end because a large number of longitudinal rebars of the beam were not and could not be placed through the confines of the column. Use the download button below or simple online reader. Design of one way and two way slabs, design of staircases. The example presented here is for twoway posttensioned design.
In the design of structures, the aim is to design the structure in such a way that it fulfils its intended purpose during its intended life time and be adequately. The following example illustrates the design methods presented in aci 31805 and ibc 2003. Analysis and design of slabs two way civil engineers pk. The pca computer program pcaslab can be used to expedite the design of different slab systems. Bending will take place in the two directions in a dishlike fo. The basic design procedure of a two way slab system has five steps. 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. Summary and comparison of twoway slab design results. Direct design method of flat plates per aci 31802 two way slabs are inherently difficult to analyze by conventional methods of statics because of the two way bending occurring.
The behaviour of reinforced concrete beam sections at ultimate loads has been explained in. European commission joint research centre institute for the protection and security of the citizen contact information address. The 2012 edition of the reinforced concrete design manual sp1711 was developed in accordance with the design provisions of aci 31811, and is consistent with the format of sp1709. Jul 08, 2015 slabs are constructed to provide flat surfaces, usually horizontal, in building floors, roofs, bridges, and other types of structures. Here are the steps for the design procedure for one way slab in steps. In this example deflection will be calculated and checked to satisfy project deflection. Design of twoway slab by coefficient method the constructor.
When you model a building structure, you can use the design links function to select a series if beam elements and export the analysis results geometry together with the bending moment and shear force envelopes to continuous beamslab design. A monolithic reinforced concrete floor is to be composed of rectangular bays measuring, as shown. Slab design reading assignment chapter 9 of text and, chapter of aci31802. Distribute moments transverse at critical sections to column and middlestrip and if. Design of reinforced concrete structures ii twoway slabs 1 1. 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 of reinforced concrete structures ii two way slabs 1 1. I have developed a microssoft excel software for design of a two way rcc slab. One way spanning slabs should be treated as beams of unit width and chapter 2 should be followed except for minimum shear reinforcement. Flat slab analysis, design and detailing pdf civil. Direct design method of flat plates per aci 31802 twoway slabs are inherently difficult to analyze by conventional methods of statics because of the twoway bending occurring. Pdf the article is about design of prestressed slabs. Determine suitable dimensions for the effective depth and width of the beam. Unless otherwise noted, all referenced table, figure, and equation numbers are from these books.
Manual for the design of reinforced concrete building. The building is located in seismic zone iii on a site with medium soil. The output of the program for the slab in the example is shown in the following pages. Layout of posttensioning reinforcement in floor slabs by dr. Two way slabs have two way bending unlike one way slab. There are many methods that are used to analyze two way slabs and the precision of these methods vary depending. This paper focuses on analysis of two way ribbed and waffle slabs with hidden beams. Bending will take place in the two directions in a dishlike form. Mar 10, 2018 design steps for rcc one way slab by prof. Reinforced concrete design to bs8110 structural design 1 lesson 5 5 4. Aci 31811 code provides two methods for two way slab design one of which is.
Multistorey residential building 111 appendix c floor design using lattice slab 115 c. The institution of structural engineers the institution of civil engineers march 2000 manual for the design of reinforced concrete building structures to ec2. Load calculations page 1 of 6 load calculations according to asce 7. Twoway edge supported ribbed slabs design methods in the aci code 31808, two empirical methods are given for analysis and design of twoway slabs, regardless of their types. Design of abutment excel sheet there is document design of abutment excel sheet available here for reading and downloading. Twoway concrete floor slab with beams design and detailing csa.
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 twoway slab with beams in both directions. Where the slab acts compositely with a beam, or is used as a diaphragm. Following are the rcc slab design and detailing guidelines. 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. Shear strength of two way slabs shear failure occurs when inclined cracks form due to flexural and shearing stresses. 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. Design of slabtwo way excel sheet online civilforum. Shear failure occurs when inclined cracks form due to flexural and shearing stresses. Lets take an example the below twoway slab diagram. The example presented here is for two way posttensioned design. Design procedure steps for one way slab slab design steps. Two types of shear failure mechanism in 2way slabs.
Reinforced concrete design to bs8110 structural design 1 lesson 5 1 lesson 5. How to design a twoway slab free download as powerpoint presentation. For example, it is possible to decrease the amount of reinforcement at one section if a corresponding increase is introduced at another section. Twoway slab design using the coefficient method free download as pdf file. Chapter 3 design of rectangular beams and oneway slabs 12. Minimum uniformly distributed live loads for building design. The program covers wide range of two way slab systems and can be used for more complex slab layouts. 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. Accurately determining the moments on a two way slab is typically accomplished by finite element computer analysis. Analysis and design of slabs two way two way edge supported slabs two way slabs.
The design bending moment of twoway restrained slab can be calculated as follows. Pdf cost optimum design of reinforced concrete simply. According to the way loads are transferred to supporting beams and columns, slabs are classified into two types. They may be supported on two opposite sides only fig. The purpose of this document is to summarise the way that aluminium profile. The slab has to carry a distributed permanent action of 1. The joint was considered as a slabcolumn joint and analyzed, in the eastwest direction, on the premise that the slab acted as a two way slab near the column. The basic design procedure of a twoway slab system has five steps. 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. This example is to be used for educational purposes only. Twoway slab design using the coefficient method beam.
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