An illustrative example of a two way slab as per is 4562000. 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. Sep 03, 2011 reinforced concrete sk 33 section through slab showing stress due to moment. Reinforced concrete design 1 design of slab examples. Flat slab analysis, design and detailing pdf civil.
Innovation in this field of concrete design has led to the development of design rules that enable. Manual for design and detailing of reinforced concrete to. Because of the brittle nature of shear failures, conservative design is necessary. Design and analysis of retaining walls 2 economical when the wall height exceeds 8m. The design of the gusset plates connecting the buckling restrained braces to the precast concrete embedment plates was the responsibility of the steel fabrica. When a client chooses to construct and test a restrained assembly, it results in two assembly ratings. The slab has to carry a distributed permanent action of 1. Design of two way restrained slab as per is 4562000. For example, in a 4inch 100 mm thick slab the joint spacing should be about saw cut tooled wall or column expansion joint material slab on grade column contraction joints intersect at diagonals of the square form openings which will be filled after floor has hardened concrete cracks below joints slab isolated from. Basing design on equation 3 means that the full strength of the crosssection in bending is now being used, with the design condition being given by. Torsion steel must be provided at discontinuous edges as specified in code.
Hollowcore is very economical and provides great design flexibility. Reinforced concrete slab design and detailing guide is456. Feb 25, 2019 a restrained slab means its ends are not free to rotate. Design of slabs and plates and under the heading lithe problem. Oneway and twoway slabs oneway slabs transfer the imposed.
Precast concrete floors in steel framed buildings a g j way meng, ceng, mice t c cosgrove bsc, msc, dic, miei. Civil engineering faculty of civil engineering and earth resources universiti malaysia pahang june 2015. The following table of prestress losses is recommended for the design of posttensioned members, and does not include friction or wedge set losses. Oasys safe models undrained behaviour by a consolidation analysis with very low permeability and a very short time period, which was used with elastic effective stress parameters. It provides a working flat surface or a covering shelter in buildings. Based on the information provided, design slab panel bc12. Pdf arching action strength enhancement in laterallyrestrained. This strip is designed basically as if it were a 12inchwide beam, t inches thick. Manual for design and detailing of reinforced concrete to the september 20 code of practice for structural use of concrete 20 2.
Design of reinforced concrete structures ii twoway slabs. Ce 403, fall 20 oneway slab design 2 4 aci 31811 referenced pp 2 4 typical concrete floor systems copied from ceco concrete construction pamphlet design procedure a oneway slab is designed by considering a onefootwide strip of slab. Mfyd 4 where m is the moment at crosssection under consideration and fyd is the design strength material yield strength divided by a suitable material factor. The design of the gusset plates connecting the bucklingrestrained braces to the precast concrete embedment plates was the responsibility of the steel fabrica. Whereas, if bracing is in front of the wall and is in compression instead of tension, the wall is called buttress retaining wall. Pdf compressive membrane action strength enhancement in. However, the only standard test on this issue is the restrained. Reinforced concrete slab design and detailing guidelines for depth of slab, loads on slab, reinforcement guide for oneway. Design of slab examples and tutorials by sharifah maszura syed mohsin example 1. Two way slab is a slab in which the ratio of longer side to the shorter side is less than or equal to two. Two way slabs are classified into two types based on the support conditions. General a slab is a flat two dimensional planar structural element having thickness small compared to its other two dimensions.
The scope of this publication is to provide guidance on the design and construction. Design and construction of joints for concrete streets. Evaluating the combined effect of restrained tempera ture curling and moisture warping is complicated due to their opposing nature. Oneway and twoway slabs oneway slabs transfer the imposed loads in one direction only. Openweb steel joists, steel beams, or metal decking supporting continuous concrete slab restrained 2. Flexural restraint provided for slab by the exterior column or the exterior wall. For this slab, panel a has two discontinuous exterior edges and two continuous interior edges, panel b has one discontinuous and three continuous edges, while the interior panel c has all edges continuous. They may be supported on two opposite sides only fig. May 22, 2018 talking about a simple explanation for your question. Reinforced concrete buildings series design booklet rcb2.
Behavior of partially restrained reinforced concrete slabs 12 personal authors guice, l. Tn462 temperature design 060116 adapt software help. The design bending moment of twoway restrained slab can be calculated as follows. Saccoman, chairperson james beerbower ernest markle kevin boyle james markle jeffrey butler milo j. For instance, when the top of the slab is warmer than the bottom, causing the top to expand, the bottom of the slab usually has a higher moisture content causing it. Feb 21, 2019 an illustrative example of a two way slab as per is 4562000.
Slabs are designed for flexure in two orthogonal directions for both hogging and sagging moments. 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. Accordingly, main reinforcement is required in the two directions. The design booklets of the reinforced concrete buildings series have each been written to form two separate parts. Actual losses, whether greater or smaller than computed values, have little effect on the design strength of the member but do affect service load conditions i. Simply supported one way slab a rectangular reinforced concrete slab is simplysupported on two masonry walls 250 mm thick and 3. Mfyd 4 where m is the moment at crosssection under consideration and fyd is the design strength material yield strength divided by. Jan 17, 2018 the restrained slab, shown crosshatched, was not included in the model, but its effect was represented by restraining the nodes at the surface of the clay.
Certainly, considerably more money is being spent on fire proofing due to the new interpretations. Part 1 as 3600 design which provides insight into major new developments in as 3600. This condition occur when the slabs are connected monolithically with support. The construction materials consist of grade c25 concrete and 500 steel. Find the following parameters for design moments in step 2 per unit width step 4 note. Bending will take place in the two directions in a dishlike form. Effective heave pressures beneath restrained basement. Effective heave pressures beneath restrained basement slabs.
Middle strip is forming threefourth of slab width in width directions. Following are the rcc slab design and detailing guidelines. Programming for reinforced concrete design for twoway restrained solid slab to eurocode 2 muhammad iqbal hisyam b mohd zahari thesis submitted in fulfillment of the requirements for the award of the degree of b. The instantaneous drop in temperature that will lead to cracking of restrained concrete is therefore. Waffle slabs are supported on beams or columns, where the support zones are made to be uniformly. Joint free restrained slabs sfrc combined with mesh.
A civil engineer must know all the aspects regarding the flat floor system. Oneway and twoway slabs university of asia pacific. The analysis and design of posttensioned, twoway slabs incorporate the full tributary slab width without the distribution of forces and reinforcement between column strips and middle strips, synonymous with mild reinforced two. The approach to blastresistant design of reinforced concrete slabs is to design the slab so that the maximum deflection under the blast load is less than some. The reasons for abandoning the astm guidelines for determining whether a structure is restrained or unrestrained are not clear to the authors. Design of two way restrained slab as per is 4562000 part 2. A restrained assembly rating is determined by the rise in temperature at the slab top surface, the prevention of flame passing through the assembly or the ability to carry the load. Manual for design and detailing of reinforced concrete to the. It also specifies that restrained construction shall. Reinforced concrete sk 33 section through slab showing stress due to moment.
Openweb steel joists or steel beams, supporting precast units or metal decking unrestrained 3. Flat slab system is an important division of concrete floor system. General overview of posttensioned concrete design instructor. Here, we have tried to gather various reading materials available in the web about flat slab floor system in one place. Design of slab for flexure 067 m unit width of slab. The restrained slab, shown crosshatched, was not included in the model, but its effect was represented by restraining the nodes at the surface of the clay. Talking about a simple explanation for your question. Put a stick on two supports which are about of 3 to 4 meters apart. That is, they are restrained against moving during a fire loading. This restraint modifies the reactions and therefore. A combination of these values will determine the slab stresses at the time of stressing and at service loads. Corus construction and industrial provided funding for p342 and p344 and corus construction centre for p287. The professional development series is a unique oppor.
These guidelines are appropriate for simply supported slabs but are underestimating laterally restrained slabs such as deck slabs in beam and slab bridge structures where the benefits of arching. These materials are originally located at different websites. Slab design reading assignment chapter 9 of text and, chapter of aci31802 introduction aci318 code provides two design procedures for slab systems. For instance, when the top of the slab is warmer than the bottom, causing the top to expand, the bottom of the slab usually has a higher moisture content causing it to expand. Design of twoway slabs restrained two way slab is divided into middle strip and edge strips. Design and analysis of retaining walls 3 f crib walls or coffer dams are cells or units to be filled with soil or builtup members of pieces of precast concrete or metal and are supported by anchor pieces embedded in the soil for.
Design of slab examples and tutorials by sharifah maszura syed mohsin. Example on structural design of waffle slab structville. Flat slab analysis, design and detailing pdf civil engineering. The result is a slight strengthening and stiffening in the span direction, but this effect is small and can be disregarded. It dose not include design for shear or punching shear checks. It is primarily used as a floor and roof deck system. A restrained slab means its ends are not free to rotate. Design of reinforced concrete structures ii twoway slabs 1 1. Novel use of bucklingrestrained braces in precast concrete.
Pdf shrinkage cracking of restrained concrete slabs. In a oneway slab, this lateral expansion is resisted by adjacent slab strips, which tend to expand also. The bs8110 slab design brief is for any slab modeled with f. These include end restrained or base restrained slabs, passive and activerestraint setups, and restrained ring tests 1415. On the other hand, jointed pavements slabs are detailed and designed in such a way as to limit the stresses in the slab due to restrained, temperature and shrinkage deformations to be less than the tensile capacity of the concrete, i. The design of waffle slabs is the same as that of ribbed slabs, with the difference being that waffle slabs have ribs spanning in both directions, and the coefficients used for analysing the slab is similar to those used for twoway restrained slab. Pci manual for the design of hollow core slabs second edition by donald r. In axially restrained slabs, such displacements are prevented by the support. Doubly symmetric i section has been used throughout for the development of the theory and later discussion. It also specifies that restrained construction shall be identified on the construction documents.
The design bending moments are zero at discontinuous ends, negative at continuous ends and positive at midspans. Arching action strength enhancement in laterallyrestrained slab strips. Prepared for the pci hollow core slab producers committee john e. Hollowcore is an extruded, prestressed concrete slab with continuous voids to reduce weight and cost. Reinforced concrete design 1 design of slab examples and.
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