Reinforced concrete sk 33 section through slab showing stress due to moment. 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. Reinforced concrete slab design and detailing guide is456. 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. Prepared for the pci hollow core slab producers committee john e. These materials are originally located at different websites. The design bending moment of twoway restrained slab can be calculated as follows. Talking about a simple explanation for your question.
Bending will take place in the two directions in a dishlike form. Manual for design and detailing of reinforced concrete to. Design and construction of joints for concrete streets. Behavior of partially restrained reinforced concrete slabs 12 personal authors guice, l. 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. Two way slab is a slab in which the ratio of longer side to the shorter side is less than or equal to two. Accordingly, main reinforcement is required in the two directions. Oneway and twoway slabs oneway slabs transfer the imposed loads in one direction only. Pdf compressive membrane action strength enhancement in. Design of reinforced concrete structures ii twoway slabs. The slab has to carry a distributed permanent action of 1. 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 bs8110 slab design brief is for any slab modeled with f.
This restraint modifies the reactions and therefore. 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. Tn462 temperature design 060116 adapt software help. Arching action strength enhancement in laterallyrestrained slab strips. Hollowcore is an extruded, prestressed concrete slab with continuous voids to reduce weight and cost. Based on the information provided, design slab panel bc12. Pci manual for the design of hollow core slabs second edition by donald r. The design booklets of the reinforced concrete buildings series have each been written to form two separate parts. Example on structural design of waffle slab structville. The scope of this publication is to provide guidance on the design and construction. 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. Corus construction and industrial provided funding for p342 and p344 and corus construction centre for p287. Design of slab examples and tutorials by sharifah maszura syed mohsin example 1.
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. 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. Part 1 as 3600 design which provides insight into major new developments in as 3600. The construction materials consist of grade c25 concrete and 500 steel. A combination of these values will determine the slab stresses at the time of stressing and at service loads. Feb 21, 2019 an illustrative example of a two way slab as per is 4562000. Novel use of bucklingrestrained braces in precast concrete. A civil engineer must know all the aspects regarding the flat floor system. Joint free restrained slabs sfrc combined with mesh. Saccoman, chairperson james beerbower ernest markle kevin boyle james markle jeffrey butler milo j. Effective heave pressures beneath restrained basement. Flat slab analysis, design and detailing pdf civil. Here, we have tried to gather various reading materials available in the web about flat slab floor system in one place.
It is primarily used as a floor and roof deck system. Following are the rcc slab design and detailing guidelines. Oneway and twoway slabs university of asia pacific. 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. It dose not include design for shear or punching shear checks.
Mfyd 4 where m is the moment at crosssection under consideration and fyd is the design strength material yield strength divided by. Flat slab system is an important division of concrete floor system. 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. Openweb steel joists or steel beams, supporting precast units or metal decking unrestrained 3. Design of twoway slabs restrained two way slab is divided into middle strip and edge strips. 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. Design of reinforced concrete structures ii twoway slabs 1 1. May 22, 2018 talking about a simple explanation for your question. Pdf arching action strength enhancement in laterallyrestrained. The professional development series is a unique oppor. Hollowcore is very economical and provides great design flexibility. The design bending moments are zero at discontinuous ends, negative at continuous ends and positive at midspans. Design of slab examples and tutorials by sharifah maszura syed mohsin. In axially restrained slabs, such displacements are prevented by the support.
An illustrative example of a two way slab as per is 4562000. Civil engineering faculty of civil engineering and earth resources universiti malaysia pahang june 2015. Reinforced concrete buildings series design booklet rcb2. A restrained slab means its ends are not free to rotate. Reinforced concrete design 1 design of slab examples and. However, the only standard test on this issue is the restrained. General overview of posttensioned concrete design instructor. Reinforced concrete slab design and detailing guidelines for depth of slab, loads on slab, reinforcement guide for oneway. 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. Design of two way restrained slab as per is 4562000. Design of slabs and plates and under the heading lithe problem. It provides a working flat surface or a covering shelter in buildings. It also specifies that restrained construction shall.
Precast concrete floors in steel framed buildings a g j way meng, ceng, mice t c cosgrove bsc, msc, dic, miei. When a client chooses to construct and test a restrained assembly, it results in two assembly ratings. Flexural restraint provided for slab by the exterior column or the exterior wall. 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. Design of slab for flexure 067 m unit width of slab. 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.
The design of the gusset plates connecting the bucklingrestrained braces to the precast concrete embedment plates was the responsibility of the steel fabrica. Simply supported one way slab a rectangular reinforced concrete slab is simplysupported on two masonry walls 250 mm thick and 3. Design of two way restrained slab as per is 4562000 part 2. Effective heave pressures beneath restrained basement slabs. The reasons for abandoning the astm guidelines for determining whether a structure is restrained or unrestrained are not clear to the authors. Reinforced concrete design 1 design of slab examples. Oneway and twoway slabs oneway slabs transfer the imposed. General a slab is a flat two dimensional planar structural element having thickness small compared to its other two dimensions. Slabs are designed for flexure in two orthogonal directions for both hogging and sagging moments. The result is a slight strengthening and stiffening in the span direction, but this effect is small and can be disregarded.
The instantaneous drop in temperature that will lead to cracking of restrained concrete is therefore. In a oneway slab, this lateral expansion is resisted by adjacent slab strips, which tend to expand also. It also specifies that restrained construction shall be identified on the construction documents. Feb 25, 2019 a restrained slab means its ends are not free to rotate. Two way slabs are classified into two types based on the support conditions. Certainly, considerably more money is being spent on fire proofing due to the new interpretations. Whereas, if bracing is in front of the wall and is in compression instead of tension, the wall is called buttress retaining wall. The following table of prestress losses is recommended for the design of posttensioned members, and does not include friction or wedge set losses. Manual for design and detailing of reinforced concrete to the september 20 code of practice for structural use of concrete 20 2. Pdf shrinkage cracking of restrained concrete slabs. 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. Doubly symmetric i section has been used throughout for the development of the theory and later discussion.
They may be supported on two opposite sides only fig. Innovation in this field of concrete design has led to the development of design rules that enable. Design and analysis of retaining walls 2 economical when the wall height exceeds 8m. That is, they are restrained against moving during a fire loading. Waffle slabs are supported on beams or columns, where the support zones are made to be uniformly. This strip is designed basically as if it were a 12inchwide beam, t inches thick. Openweb steel joists, steel beams, or metal decking supporting continuous concrete slab restrained 2. Evaluating the combined effect of restrained tempera ture curling and moisture warping is complicated due to their opposing nature. 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. These include end restrained or base restrained slabs, passive and activerestraint setups, and restrained ring tests 1415. Because of the brittle nature of shear failures, conservative design is necessary. 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.
Put a stick on two supports which are about of 3 to 4 meters apart. Slab design reading assignment chapter 9 of text and, chapter of aci31802 introduction aci318 code provides two design procedures for slab systems. 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. Sep 03, 2011 reinforced concrete sk 33 section through slab showing stress due to moment. Manual for design and detailing of reinforced concrete to the. Find the following parameters for design moments in step 2 per unit width step 4 note. Torsion steel must be provided at discontinuous edges as specified in code.
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. 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. The design of the gusset plates connecting the buckling restrained braces to the precast concrete embedment plates was the responsibility of the steel fabrica. Middle strip is forming threefourth of slab width in width directions. This condition occur when the slabs are connected monolithically with support. Flat slab analysis, design and detailing pdf civil engineering.