Fem is a powerful tool used in the analysis of flat slabs. Twoway joist concrete slab floor waffle slab system. The method requires solving many algebraic equations simultaneously, which is completed with the aid of a computer. Finite element analysis of slab and a comparative study with. At first i modelled one single floor and my moment map didnt look right hogging moment where theyre supposed to be sagging. Finite element analysis of effect of punching shear in. The lateral loads are independently resisted by shear walls. An analytical procedure is presented for simulating punching failure. The finite element method fem, or finite element analysis fea, is a computational technique used to obtain approximate solutions of boundary value problems in engineering. Finite element analysis is useful numerical technique to solve various structural problems.
Comparative study of reinforced concrete flat slabs with and. Recommendations for finite element analysis for the design of. Katti2 1pg student, department of civil engineering,sapkal knlowedge hub college of engineering,nashik. Apr 04, 2019 in this file, a concrete slab that has been tested in the laboratory has been modeled in abaqus. Due to the constraints of the academic version the size of the problem had to be limited. Also, the finite element analysis of the slab panels has been carried out by using ansys workbench 14. Punching shear analysis of reinforced concrete flat plates. The static analysis is performed in two load steps. Flat slab, slabcolumn connection, finite element, eccentric load. Aug 01, 2018 how to design reinforced concrete flat slabs using finite element analysis.
Katti, department of civil engineering,sapkal knlowedge hub college of engineering,nashik. Reinforced concrete slabs are structural systems most commonly used for roofing multistory buildings and hotels. Initial developments in the area of interval arithmetic will be discussed. Abstract paper presents analysis of flat slab with drop panel subjected to realistic concentrated loadings trapezoidal load, line load and patch load. A nonlinear three dimensional finite element analysis has been used to conduct an analytical investigation on the overall behavior of reinforced concrete flat slabs. It has already been shown that lusas is capable of designing this slab using a finite element analysis. Finite element analysis fea we have facilities for the production of finite element analysis fea calculations in all materials. Finite element analysis the finite element method predicts the behavior of larger more complex structures by separating the structure into smaller mathematically discrete parts called elements.
Request pdf finiteelement analysis and load rating of flat slab concrete bridges a significant portion of the nations aging bridge inventory consists of flat slab concrete bridges. Pdf finite element implementation of punching shear behaviors in. Guide to the design and construction of reinforced concrete flat slabs 1. Finite element analysis of slab and a comparative study. Care is needed in modelling the geometry, material properties and loads on the structure. It was created in lusas civil and structural academic version. Pdf shear stress distribution of flatplate using finite. Mohammed 1, nildem taysi, dia eddin nassani2 and ali k.
Finite element method based upon the division of complicated structures into smaller and simpler pieces elements whose behaviour can be formulated. A concrete slab is shown below which has the same setting out dimensions as the slab in example 6. Easy to use software becoming more widely available very accurate if used properly better than grillage. Pdf finite element analysis of effect of punching shear in. This method allows the design of irregular column layoutsand can provide the. Keywords soil structure interaction, stresses distribution, modulus of sub grade reaction ks. Within this framework, several aspects should be investigated such as the loaddeformation response of the slab, the failure mechanism, and the. Lusas finite element analysis the analysis was done for the typical flat slab arrangement shown above. Pdf understanding the behavior of flat slab by linear. Optimization techniques may be effective in finding alternative design of posttensioned slabs to improve their mechanical behaviour, particularly reducing the bending moments. Many parameters related to fire resistance of the flat slabs have been studied and the finite element analysis results reveal that the width and thickness of the slab, the temperature gradient, the fire direction, the exposure duration and the thermal restraint are important factors that influence the vertical deflection, bending moment and. The slabs effect on the overall economy of the structural system. Finite element analysis of concrete filled tube column to. Our software has plate and shell elements and automeshing facilities, allowing us to analyse the most complex of shapes.
Finite element analysis of slab and a comparative study with others analytical solution 266 7th icct 2004 m 24 pp265272 1 introduction slabs are most widely used structural elements of modern structural complexes and the reinforced concrete slab is the most useful discovery for supporting lateral loads in buildings. Finite element analysis of rc slab with or without opening. The corresponding design equation was then proposed based on finite element analysis of 82 parametric models. The development of a linear numerical model of flat plate to predict shear stress distribution around slab column connection is presented in this paper. Finite element method fem is another method for analyzing reinforced concrete slabs, particularly useful for irregular slab systems with variable thicknesses, openings, and other features not permissible in ddm or efm. In this paper fea model of slab column connection is model using ansys 16. Behaviour of flat slab a study by finite element analysis. Reinforcing a flat slab using oneway spanning rollout mats this guide outlines the benefits of using flat slab. Ngo and scordelis 1967 presented the first finite element analysis of reinforced concrete that included the effect of cracking.
Pdf nonlinear finite element analysis of rc flat slabs. Pdf finite element analysis of effect of punching shear. Flat slab structures show significant vulnerability under lateral and vertical seismic loading as punching shear failure may occur in the joints of slab and column. Aug 27, 2015 guide to the design and construction of reinforced concrete flat slabs contents membersof the projectsteeringgroup list of tables vii iv list of figures v 1. Flat slab is defined as one sided or twosided support system with sheer load of the slab being concentrated on the supporting columns and a square slab called drop panels. Comparative study of reinforced concrete flat slabs with. The field is the domain of interest and most often represents a.
The hot rolling process to form i or h section beam is simulated statically using rezoning. Recommendations for finite element analysis for the design. However, there are some pitfalls to avoid, that often catch out the unwary. Guide to the design and construction of reinforced concrete. Finite element analysis in software safe of rectangular flat slab panels under gravity loads is carried out for the different panel aspect ratio 1. These elements have a simple geometry and are easier to analyze. Guide to the design and construction of reinforced concrete flat slabs contents membersof the projectsteeringgroup list of tables vii iv list of figures v 1. The development of a linear numerical model of flatplate to predict shear stress distribution around slab column connection is presented in this paper. Then i created one slab for each panel and i got a moment map that satisfied me. Finite element analysis of effect of punching shear in flat slab using ansys 16. Flat slab, shear wall, linear dynamic analysis, base shear, time period, story drift, storey displacement 1 introduction from last two decades there is a high increase in the high rise buildings and modern trend is towards high rise. Introduction to fem finite element method fem is a technique in which not. This is a study aimed at providing guidance for the use of finite element analysis programs. The simplest type of twoway slab is known as a flat plate.
Analysis of flat sanalysis of flat sllabab moment division example 6000 6000 6000 6000 6000 5000 layout of building 7000 5000 a floor slab in a building where stability is provided by shear walls. Finite element implementation of punching shear behaviors in. Punching of flat slabs design for shear at th e column heads 12. In consideration of the economy and constructability of the connections, a final detail was adopted. The relative cost of computer hardware and software has reduced significantly over recent years and many engineers now have access to powerful software such as finite element fe analysis packages. If cracking has to be avoided, an elastic method of analysis, i. The objective of this study was the development of a procedure in gt strudl to design reinforced concrete flat plate systems based on the results. Finite element implementation of punching shear behaviors. Later on, hong guan 2009 applied the nonlinear layered finite element method lfem. Flat slab types of flat slab design and its advantages flat slab is a reinforced concrete slab supported directly by concrete columns without the use of beams. The procedure is validated for a largescale reinforced concrete flat slab without shear reinforcement that failed in punching. Understanding the behavior of flat slab by linear a nd nonlinear finite element analysis 7. In order to simplify the analysis and to be able to use the superposition principle for evaluating the effect of load combinations, linear analysis is generally adopted even though concrete slabs normally have a pronounced nonlinear response. Punching shear, nonlinear analysis, finite element analysis, reinforced concrete, flat plate, 3dimension compression steel.
Finite element analysis and optimization of bonded post. Boundary value problems are also called field problems. Analytical study of solid flat slab and voided slab using. Guide to the design and construction of reinforced. Finite element analysis and optimization of bonded posttensioned concrete slabs abbas h. Thus it is necessary to design them in such a way that keeping the economy in minds the strength of slabs can be increased. Parametric study of flat slab with various loading types.
In this research, finite element analyses have been carried out to predict how much seismic loading a flat slabcolumn connection can endure. The slab is now designed by a hand analysis to bs8110. A three dimensional finite element model fem is developed through ansys 10 computer software, to carry out the nonlinear analysis of 16 flatslab models with. Our software has an automated module which reads the stresses in the finite element analysis output for the slab being designed, and details reinforcement in accordance with the stresses such that reinforcement placed in the slab is at an absolute minimum. Punching shear failure is a major problem encountered in the design of reinforced. In this study finite element analysis of the flat slabs is proposed. This paper presents finite element analysis of slabcolumn connection in. As part of the computeraided structural engineerlng case committee study, it focuses on techniques for concrete flat slabs. Within this framework, several aspects should be investigated such as the loaddeformation response of the slab, the failure mechanism, and the load contribution of the shear reinforcement. Analysis of flat slab with and without opening international. Introduction a slab is a flat two dimensional planar structural element having thickness is small as compared to its other two dimensions. The finite element method predicts the behavior of larger more complex structures by separating the structure into smaller mathematically discrete parts called elements. Most finite element programs are based on elastic moment distribution and material that obey hookes law.
Effects of openings on the punching shear strength of. A threedimensional finite element method is used to perform the analysis. Finiteelement analysis and load rating of flat slab. Introduces finite element fe methods, explains successful concrete modelling and interpretation of results. Also highlights the benefits, and some of the common pitfalls of fe analysis, and gives guidance on best practice. Introduction to finite element analysis fea or finite. The corresponding design equation was then proposed based on.
Use of finite element fe analysis has particular advantages when the floor has irregular supports or geometry, large openings or carries concentrated heavy loads. Different models of the flat slab are analysed by finite element. With a purpose of developing criteria for finite element analysis of flat slab floors, this report has two objectives. Many reputable commercial fem analysis software packages are available on the market today such as spmats. An attempt is made to model the slab, flexural reinforcement and shear reinforcement using three. Compared to other counterparts, flat slabs are twoway slabs that are widely used due to their numerous advantages. Twoway joist concrete slab floor waffle slab system analysis and design design the concrete floor slab system shown below for an intermediate floor with partition weight of 50 psf, and unfactored live load of 100 psf. Nonlinear finite element analysis has become very useful in modelling complicated structural systems and their behaviour. In this paper, an attempt has been made to utilize a tension softening material tsm model to simulate the full precracking and postcracking response of fibre reinforced concrete flat slabs at slabcolumn connections by finite element analysis. Finite element fe analysis, is a popular powerful computer method of analysing flat slab concrete structures.
Department of mechanics, materials and structures english. The field is the domain of interest and most often represents a physical structure. The elements can be triangular, rectangular or quadrilateral. Flat slab types of flat slab design and its advantages.
This publication seeks to introduce fe methods, explain how concrete can be successfully modelled and how to. Com parison of designing flat slabs using finite elem ent analysis. How to design reinforced concrete flat slabs using finite element analysis. How to design reinforced concrete flat slabs using finite. A reinforced concrete rc flat slab is a twoway structural element, which carries vertical and horizontal loads, and transfers them directly to the. Use of finiteelement fe analysis has particular advantages when the floor has irregular supports or geometry, large openings or carries concentrated heavy loads. Pdf understanding the behavior of flat slab by linear and. Finite element analysis of impactperforated reinforced. The finite element method is commonly used to design the reinforcement in concrete slabs. Studies that followed attempted to represent discrete cracks that occur during a load cycle, but the need to change the topology of the finite element mesh greatly hindered the speed of the process. In accordance to such research, the lfem is an effective tool in global analysis and. In this paper, an attempt has been made to utilize a tension softening material tsm model to simulate the full precracking and postcracking response of fibre reinforced concrete flat slabs at slab column connections by finite element analysis. In this model, structural analysis is defined as nonlinear static type and materials has been.
Finite element analysis of effect of punching shear in flat. Validation of the developed numerical model was carried out by means of comparisons with test results. Hi, im pretty new to finite element design and i was trying to design a flat slab. Therefore, the principal aim was the nonlinear finite element analysis of flat slabs with large amounts of punching shear reinforcement. Numerical analysis of a reinforced concrete slabcolumn. Interval finite element analysis is being shown as an efficient tool to analyze large and complicated structures which otherwise are impossible to be analyzed for all possible load patterns and load combinations. This publication seeks to introduce fe methods, explain how concrete can be successfully modelled and how to interpret the results. Therefore, three types of cft column with flat plate slab connections were initially proposed. The validated finite element procedure is then used to estimate the minimum velocity of the impactor required to perforate, in the sense of the socalled ballistic limit, a 150 mm thick twolayer reinforced concrete slab for impactor weights 250 kg, 500 kg and kg.
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