However, flat slabs have a lower stiffness in comparison to a beamcolumn floor plan which can lead to relatively large deflections. Seismic analysis of flat slab structure by linear static method and response spectrum method seismic response of torsion the parametric studies comprise of base shear of structure. They increase the shear capacity and the stiffness of the floor system under vertical loads, thus increasing the economical span range. As manual calculation method the method of substitutive frames or substitutive beams can be applied. The flat plate is a twoway reinforced concrete framing system utilizing a slab of uniform thickness, the simplest of structural shapes. The procedure is consistent with the navys current blastresistant design manual navfac p397 and is. Flat slab flat slabs thin structure flat soffits no beams 80% of concrete framed buildings are flat slabs 4 million m2 built each year in uk. The slab is part of a larger floor plate and is taken from guide to the design and construction of reinforced concrete flat slabs29\ where finite element analysis and design to eurocode 2 is illustrated. These slabs are classically used in foundations, although they can also be used in the construction of roadways, paths, and other structures. There are many methods to incorporate lateral load resisting ability into a structure.
On comparison the displacement for flat slab is found to be less than conventional slab structure, the variation is 64 %, 56% and 41% for six, eight and ten storey building. Flat slab types, uses, advantages and disadvantages. Lande 2015 discussed about flat slab structure is most vulnerable to the seismic excitation therefore the careful analysis of flat slab is important. Blast design procedure for flat slab structures dtic. These materials are originally located at different websites. Direct design method ddm twoway slabs satisfying the limits in aci 31814 8. Seismic analysis of flat slab structure sukanya sawant prof k. Progressive collapse of reinforced concrete flat slab. Flexible column arrangements, this is more difficult to achieve for a beamcolumn design. This is primarily due to their ability to develop alps. Feb 22, 2018 civil engineering for construction informatics csi etabs 2016 flat slab design, strip design and punching shear check please have a look in this video thank subscribe our youtube channel to get. Beside this, due to shear problems at column heads, the thickness of flat slab is greater. Hence the slab is thickened near the columns by providing the drops as shown in fig. Chapter 18 concrete slab structures january 2019 183 18.
Review paper on behavior of flat slab under dynamic loading. Extend horizontally from center line column at least 16 center line span. As this structure means flat slab and having there types are compared more flexible than conventional concrete frame structure, therefore becoming more. Also, experimental details of the nine flat slab panels, supported on non rectangular grid, designed using the structural membrane approach and tested at. Introduction to flat slabs modelling of reinforced. The load is transferred directly from slab to column in the flat slab.
Cost optimisation of reinforced concrete flat slab buildings according to the british code of practice bs8110 is presented. A flat slab is a oneway or twoway system with thickenings in the slab at the columns and load bearing walls called drop panels figure 9. In addition to this, the shear capacity can also be reduced in particular around the column head where large shear forces can develop. The thickness of slab over columns is also increased to support heavy loads and the thickened part of the slab is called drop panel. The comparison is made between the conventional reinforced. Static and dynamic analyses were performed using the equivalent frame method efm, finite element method fem and proposed method pm, respectively. Jul 28, 2014 the flat plate is a twoway reinforced concrete framing system utilizing a slab of uniform thickness, the simplest of structural shapes. In the present work, summarized the importance of flat slab construction and revealed the relevance of shear wall in a flat slab multistoried building. Flat slab system is an important division of concrete floor system. Maximum lateral displacement, story drift, axial forces generated in the column. Flat slab flat slab are also known as beamless slab, is a type of slab in which the flooring slab is directly supported on columns without the agency of beam or girders. Csi etabs 2016flat slab design, strip design and punching. Flat slab sized for punching shear and deflection additional reinforcement added to span steel to reduce deflections typically 25% extra on a 7. Flat slab analysis, design and detailing pdf civil engineering.
Civil engineering for construction informatics csi etabs 2016flat slab design, strip design and punching shear check please have a look in this. Flat slab haunched slab a longitudinal slab is one of the least complex types of bridge superstructures. Analyze and design flat slab or waffle slab floors. Explore flat slab with free download of seminar report and ppt in pdf and doc format. Pdf cost optimisation of reinforced concrete flat slab. Pdf analysis of flat slab structures with outriggers. The first example structure is a 20story flat slab structure with regular plan as shown in fig. Flat slab is a reinforced concrete slab supported directly by concrete columns. Twoway 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. In conventional slabbeam system, the load is transferred from slab to beam and ultimately beam to the column. This example is for the design of a reinforced concrete flat slab without column heads. Structure magazine design of concrete flat slabs to. If a flat plate or flat slab is otherwise suitable for a particular structure, it will be found that there is the additional benefit of minimizing the story height.
Flat slab structures are the best solution for high rise. Punching shear is a type of failure when reinforced concrete slabs are subjected to localized forces. In areas of absolute height restrictions, this may enable one to have an additional floor for approximately each 10 floors, as compared. Types of flat slabs, its design and advantages described. Flat slab seminar report, ppt, pdf for civil engineering. 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. Hence the flat slabs 3 l2a l2b c of panel a c of panel b middle. Depending on the size and complexity of a flat slab, it may need to be designed by an engineer who is familiar with. Introduction to flat slabs modelling of reinforced concrete. Comparative study of seismic behavior of flat slab and. Pdf irregular flat slabs designed according to the structural. The study concluded that the flat slab structure is the best solution for the high rise building as compared to conventional rc. Design of rcc flat slab structure under earthquake loading. Flat slab analysis, design and detailing pdf civil.
Also explore the seminar topics paper on flat slab with abstract or synopsis, documentation on advantages and disadvantages, base paper presentation slides for ieee final year civil engineering ce or ieee civil construction btech, be, mtech students for the year 2015 2016. Tech student assistant professor department of civil engineering department of civil engineering ghrce nagpur ghrce nagpur abstract flat slab structure represents easy construction and elegant representation of floored building. Using a drop panel and a column capital in flat slab. 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. Sometimes the drops are called as capital of the column. The early reinforced concrete flat slabs all had drops, and columns with capitals, and were considered to be the structure of. Analyses are for a onebaywide strip using the equivalent frame analysis method of the aci code. Effect of column dimensions on the punching shear of flat slab. Seismic performance of flat slab with drop and conventional. The objective function is the total cost of the building including the. Efficient analysis of flat slab structures subjected to. Also, experimental details of the nine flat slab panels, supported on nonrectangular grid, designed using the structural membrane approach and tested at. Pdf flat slabs are highly versatile elements widely used in. Reinforced concrete flat slabs are commonly used in construction as they provide a number of benefits to the designer including.
For lighter loads the column heads and drop panels are eliminated, such flat slab with constant thickness supported on prismatic columns are called flat plate. Mechanicslearner, to give you an example of the difference in possible deflection calculations for rc slabs from different software, if i run a 12m span one way slab single span i assume you have edge beams so it is not a flat slab, and at 2512 it is actually a one way slab with 600mm 600mm 4000m high columns above and below in rapt, the deflection is about 216mm including for cracking. The flat slab is a reinforced concrete slab bolstered, by a number of columns. The flat slab is a twoway reinforced concrete slab that usually does not have beams and girders, and the loads are transferred directly to the supporting concrete columns.
Pdf analysis and design of flat slab and grid slab and their. As with the guide, grid line c will be designed but, for the sake of illustration, coefficients will be. A flat plate is a one or twoway system usually supported directly on columns or load bearing walls. Flat plate concrete floor system does not use beams between columns or. Nancy debora assistant professor civil karunya university 2. Lithospheric structure of the pampean flat slab region from. It is one of the most common forms of construction of floors in buildings. Flat slab construction offers considerable flexibility to the occupier who can easily alter internal layouts to accommodate changes in the use of the structure. Analysis the simplified method for a flat slab structure whose lateral stability is not dependent on the slabcolumn connections, viz.
Is 4562000 recommends the analysis of flat slab and column structure as. Flat slabs may have drop panels at columns and columns may have capitals. Flat slab structure leads to economic saving, aesthetic view and yet allow the architect from great freedom of form works as compared to conventional slab structure. Flat slab structure with column drop and shear wall together through response spectrum method by using etabs software. Here, we have tried to gather various reading materials available in the web about flat slab floor system in one place. A civil engineer must know all the aspects regarding the flat floor system. A tendon is defined as sheathing duct, the strands within it and the corrosion inhibiting grease or grout filling its voids. Department of mechanics, materials and structures english. The following sections outline the solution per ddm, efm, and spslab software respectively. Flat slab types of flat slab design and its advantages. To improve the performance of flat slab system shear wall and beam at. The behavior of flat slab is investigated in terms of the following factors. The design method meets the requirements of aci 31814, building code requirements for structural concrete and commentary, canadian standard csa a23.
A civil engineer should study these lectures and materials for structural engineering acumen. Understanding the lithospheric structure of the current pampean flat slab segment provides a framework for studying previous flat slab dynamics, such in western north america, where many have hypothesized that the farallon plate subducted beneath the north american plate at a shallow angle during the laramide orogeny e. Structure magazine design of concrete flat slabs to resist. Thin sections allowing for greater roof heights and lighter floors. Lithospheric structure of the pampean flat slab region. However, while flexural damage is usually fairly minimal, progressive punching shear failure is a critical design condition as it may result in a complete collapse. Abhishek lakshman dhangar, a comparative study of flat slab structure and conventional structure. In this paper the seismic analysis on flat slab is performed and compared it with the conventional rc building. In conclusion, rc flat slab structures are capable of resisting progressive collapse after the loss of a column. The flat slab is a twoway reinforced concrete slab that usually does not have beams and girders, and the loads are transferred directly to the supporting concrete columns the column tends to punch through the slab in flat slabs, which can be treated by three methods using a drop panel and a column capital in flat slab. When the height of the building increases, the building should have a good lateral load resisting capacity. Punching, shear is a category for collapse for reinforced concrete slabs exposed to great confined forces. Drop panels play a significant role here as they augment the.
Flat slab subduction is characterized by a low subduction angle. While designing structure layout and during implementation using sub frame. These shear walls transfer the lateral loads to the foundation by their shearing resistance and resistance to overturning. By knowledge we know that flat slab is preferred as a floor system because of its architectural appearance, flexibility of flat slab rc structure, easy to construct and economic structure. Flat slab structure represents easy construction and elegant representation of floored building. The column tends to punch through the slab in flat slabs, which can be treated by three methods.
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