So, main reinforcement is provided in both direction for two way slabs. The following example illustrates the example building. Flat slab analysis, design and detailing pdf civil. In general, if the load from the slab is delivered to the beams in one direction, then the system is one way. A reinforced concrete slab is built integrally with its supports and consists of two equal spans, each with a clear span of 15 ft. Columns are asymetrical and part of the slab on the 2nd floor is a cantilever slab on one edge the edge with a radius. This defines whether the design is a two way slab design or one way slab design.
Two way slab design based on aci 31819 using finite element method. Gravity columns and walls are ignored in the frame finite element analysis when one way slab are used. The equivalent frame method efm presented in aci 31814 is illustrated to analyze and design two way waffle slab system. Advanced slab design mode enables concrete slabs defined with or without holes to be designed using the ramconcept or adaptbuilder software. Design of two way ribbed slab 18 x 25 m clear span 1. Two way rcc slab designing tool in microsoft excel developed by shankar tayal a 3rd year student of school of infrastructure, indian institute of technology, bhubaneswar this is a part of his project economic design of two way rcc slabs under prof s. Design the slab, following the provisions of the ack code. Slab member comparison using rapt reinforced and posttensioned concrete design software this will be a two span continuous slab 4. Slabs or foundations can be of any shape, and can include edges shaped with circular and spline curves. Two way reinforced concrete slab design clear longer span of slab please enter the longer span. Analysis of twoway slabs using direct design method. Please enter the practically physible spacing for main steel of twoway slab based on summary.
I have developed a microssoft excel software for design of a two way rcc slab. Reinforced concrete slab and beam design software adaptrc 2017 product overview an easytouse and learn software for the design, analysis, and investigation of reinforced nonprestressed concrete beams, beam frames, slabs and floor systems a must have production tool in every structural engineering office. Two way slab design spreadsheet the engineering community. The direct design method is an approximate method used to analyze two way slabs. This spreadsheet is an extremely efficient tool and allows to quickly design two way slabs to aci code. Oneway and twoway slabs university of asia pacific. Since slab spans in both directions, design reinforcement is provided in both the direction. Analysis and design of two way slabs page 1 chapter 3.
Analysis and design of slabs two way civil engineers pk. Two way rcc slab designing excel sheet civil engineering. In this case, each slab is analyzed separately by using tables. The software is developed by practicing structural engineers with emphasis on traditional indian.
At solution the program will create a finite element mesh of plates to represent the slab. I am submitting it to you and i want students or professional engineers to download it and use it for their studies or. This method was provided in the american concrete institute aci in 1963 to design two way slabs carried by steel beams, deep beam, or walls. Slabs having supports on less than four sides can be designed as one way. In two way slab, the ratio of longer span l to shorter span b is less than 2. Excel sheet for sieve analysis of aggregate and to calculate fineness modulus. The output of the program for the slab in the example is shown in the following pages. The service live load is 100 psf, and 4000 psi concrete is specified for use with steel with a yield stress equal to 60,000 psi. Slabs is a program that can be used by structural engineers to perform a static analysis and design of reinforced concrete slab systems of any shape, including suspended slabs and slabs onground.
You can perform reinforcement designs, long term deflections, beam designs, reactions, automatic two way action, effective moment of inertia, and. Download free demo updated august 8, 2019 soilstructure slab on grade software simplifies the calculation of a. Posttensioning may be included in both slabs and beams to balance a percentage of the selfweight. Area loads in oneway and twoway systems skyciv cloud. 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. Two way slab is a slab supported by beams on all the four sides and the loads are carried by the supports along both directions, it is known as two way slab.
Design of a two way rcc slab structural engineering. Simply supported one way slab a rectangular reinforced concrete slab is simplysupported on two masonry walls 250 mm thick and 3. Ram concept contains an advanced feature set that allows for the design of a wide variety of floor systems including posttensioned, reinforced concrete and hybrid systems, elevated slabs and mat. Engineering international structural design software. Two way slabs are the slabs that are supported on four sides and the ratio of longer span l to shorter span b is less than 2. Two way slabs page 6 of 14 the pca computer program pcaslab can be used to expedite the design of different slab systems. The program covers wide range of two way slab systems and can be used for more complex slab layouts. Analysis and design of slabs one way civil engineers pk. Analysis of two way slab daveatkins structural 9 sep 05 09. I know that there is aashto for deck design using one axle or point loads, but these point loads a are smaller.
This spreadsheet undertakes these calculations and returns design moments for use during detailed design. It is a finite element based analysis software which is developed specifically for design of reinforced concrete buildings. This spreadsheet performs an analysis and design of two way spanning reinforced concrete slab. Reinforced concrete design 1 design of slab examples. I have a project in school where i have to analyze a 2 story building with a slab deck on the roof. Design of slab examples and tutorials by sharifah maszura syed mohsin example 1. So part of the load is carried by one set and the remainder by the other. A civil engineer must know all the aspects regarding the flat floor system. Suspended slabs can include flat, two way, waffle, and ribbed framing systems. Determine moments at critical sections in each direction, normally the negative moments at supports and positive moment near midspan. A reinforced concrete slab is a broad, flat plate, usually horizontal, with top and bottom surfaces parallel or nearly so.
Two way slabs have two way bending unlike one way slab. A slab supported on all four edges with an aspect ratio of longer to shorter theoretical span less than. In two way slabs shorter direction strip carry greater %age of load. Reinforced concrete slab and beam design software adaptrc. I wanted to see if anyone has any good literature on two way slab design for point loads.
The slab has to carry a distributed permanent action of 1. The efm solution is also used for a detailed comparison with the analysis and design results of the engineering software program spslab. From there an analysis is considered and the program will then design the slab based on design strips. In case of two way slabs, the moment coefficient tables are applicable to two way slab system where a two way slab is continuous with a two way slab. With the advent and popularity of finite element analysis software, engineers can create sophisticated models of two way slabs supported by columns. For two way slabs, there are two options for including gravity columns and walls when analyzing gravity load cases in criteria diaphragm see below. A building usually comprises several, generally nonstandard, types of slabs one way, two way etc. Easy to use software becoming more widely available very accurate if used properly better than grillage. Analysis two way slabs are not direct as in one way slabs. Ram concept is a software application for the structural analysis and design of conventionally reinforced and posttensioned concrete floors, mats, and rafts. This paper deals w ith the yield line analysis of orthotropic reinforced concrete two way slab under the effect of uniformly distributed pressure load.
Powered by the equivalent frame method of analysis and design per latest american aci 31814 and canadian csa a23. If slab is supported on all four sides and r shorter side longer side way slab. This program is more effective for analysis the two way slab. To comply with aci 318, should a designer check punching shear stress with the simultaneous biaxial moments reported by such a model. Two way slab building design by staad pro v8i software. In two way slabs, load will be carried in both the directions. Analysis of two way slab structural engineering general. The elements can be triangular, rectangular or quadrilateral. Two way slab design based on aci 31811 using finite element method. The consideration at this point is to determine whether a system is one way or two way, allowing the tributary width and load distribution to be assigned to the member. Load transfer in a one way slab, b two way slab nilson fig.
The basic design procedure of a two way slab system has five steps. It can be used by both practicing engineers and students. 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. There are multiple analysis methods, manual and computer analysis, available for analyzing two way slabs. It is convenient to think of such slabs as consisting of two sets of parallel strips, in each direction and intersecting each other. Flat slab system is an important division of concrete floor system. Static analysis of twoway slabs, subjected to uniform load, is performed using tables, which give the fundamental support moments, span moments and shear forces. Every example ive ever seen on two way slab design is for uniformly distributed loads. Here, we have tried to gather various reading materials available in the web about flat slab floor system in one place. Analysis and design of one way and two way slab in staad. Distribute moments transverse at critical sections to column and middlestrip and if.
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