2 way slab rebar arrangement pdf

Chapter 3 fabrication and placement of reinforcing steel. Manual for the design of concrete structures to eurocode 2. Here, we have tried to gather various reading materials available in the web about flat slab floor system in one place. They may be supported on two opposite sides only fig. Rebar arrangement in slab beam structure engineering. Bars that are placed in the interior layers should follow the same spacing patterns as the main, outer reinforcement. This situation could represent a bridge slab supported between two beams or supported between an abutment and a pier, or it could represent a cul vert slab, wall, or floor. Design of reinforced concrete structures ii twoway slabs 1 1.

Chapter 3 design of rectangular beams and oneway slabs 12. The one way slab is deflected in one way direction and primary reinforcement is placed in one direction whereas. Oneway and twoway slabs oneway slabs transfer the imposed loads in one direction only. The behavior of a twoway slab is similar to that of a oneway slab the only difference being that now the slab loads will be carried in both directions. How to design concrete structures using eurocode 2. A civil engineer must know all the aspects regarding the flat floor system. This type of slab is expected to behave like a general twoway reinforced concrete slab because it has segmented voids, rather than the continuous voids of hollow core slabs. The flat slab is somewhat more expensive in labor than is the flat plate, but the forms for the column. If shear reinforcement in the form of bars is used, the limit value of nominal. Oct 27, 2016 in one way slab, the ratio of longer span l to shorter span b is equal or greater than 2, i. For these slabs, minimum reinforcement top and bottom mats probably work with some additional bars added in key locations. Pdf effects of posttensioning slippage on 2way spanning. After mixing, the concrete was poured in 50 mm thick layers into the moulds with each layer vibrated on a vibrating table for a time until no more air. Slab supported on two sides and bending takes place predominantly in one direction only is called one way slab.

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. Distribute moments transverse at critical sections to column and middlestrip and if. For one way slab, main reinforcement is computed by a formula in limit state design that is determined by comparing compressive force as well as tensile forces. In this post, we are going to explain how to calculate steel quantity for the slab. The main reinforcing in a bridge slab supported by beams is both the top and the bottom transverse reinforcing steel. One way slab reinforcement details daily civil engineering. This is a common situation for a reinforced concrete section between two supports.

Aug 23, 2017 basic concept of cranked rebar and extra top rebar in slab duration. The basic design procedure of a two way slab system has five steps. Be sure to follow rebar engineering specifications. Incorrect placement can lead to serious concrete structural failures. May 02, 2017 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. For b oth one way and two way slab with an example. Twoway concrete floor slab with beams design and detailing.

Basic concept of cranked rebar and extra top rebar in slab duration. Oneway and twoway slabs oneway slabs transfer the imposed. In many cases the slabs are of such proportions and are supported in such way that twoway action. When a slab is supported on the two different sides and the ratio of longer span to shorter span is equal to or greater than 2, it will be considered as one way slab. How to detail reinforcements of twoway slabs quora. Slab rebar arrangement 1 slab rebar arrangement slab type classification 2way slab rebar arrangement method 1way slab rebar arrangement method slab main bar arrangement type classification bent bar type union type of outer beam and slab union type of outer wall and slab ly. One way and two way slabs one way slabs transfer the imposed loads in one direction only.

Fiberreinforced polymer strengthening of twoway slabs article pdf available in aci structural journal 1015. The oneway slab is deflected in one way direction and primary reinforcement is placed in one direction whereas. The aim of the project is to learn more about structures behaviour what will help to find new design methods, both computer aided and ready solutions in form of tables. Pdf fiberreinforced polymer strengthening of twoway slabs.

Chapter 3 design of rectangular beams and oneway slabs. Slabs cast with an opening are reinforced by steel bars and slabs with a sawn up opening. Flexural design theory somewhere between the main reinforcing and the oppo site edge of the concrete is an imaginary line called the neutral axis, see figure 2. Pile supported foundation pile cap analysis and design based on a geotechnical study, a pile supported foundation is required to support a heavily loaded building column.

Determine flexural reinforcement required for column and middle. Sandwich slab reinforcement details in reality, sandwich slabs are ribbed slabs with a slab placed both to their upper and lower surface. As crosssectional area in square inches of steel per lineal foot of slab width t thickness of slab in inches fr tensile strength of concrete psi 0. Rectangular beams and one way slabs page 3 of 9 design of rectangular beams and one way slabs continued a. In two way slabs, load will be carried in both the directions. Please help promote this free service tell a friend about. Describe the procedures for placing and tying reinforcing steel. Manual for design and detailing of reinforced concrete to the code. Beam and slab arrangement can be the best example for one way and two way slabs.

Apr 12, 2018 two way slab full detail explanation diagrams with site below these links are our civil videos learn field work watch and subscribe for more videos building drawings analysis in telugu. The ratio of length to width of one slab should less than 2 otherwise oneway action is obtained, even though supports are provided on all sides. Design the pile cap shown in the following figure with 12 in. Design of isolated square and rectangular footings aci. A floor slab in a building where stability is provided by shear walls in one direction ns. The slab is without drops and is supported internally and on the external long sides by square columns. Layout and fabrication of structural steel and pipe. Rectangular beams and oneway slabs page 3 of 9 design of rectangular beams and oneway slabs continued a. Oneway spanning slabs should be treated as beams of unit width and chapter 2 should be followed except for minimum shear reinforcement. Twoway slabs are surface members acting in a both directions. Verandah slab is a type of one way slab, where the slab is spanning in the shorter direction. Difference between one way slab and two way slab daily civil. When the ratio of the longer to the shorter side l s of the slab is at least equal to 2.

This chapter describes the purpose of using reinforcing steel in concrete construction, the shapes of reinforcing steel commonly used, and the techniques and tools used by steelworkers in rebar reinforcing steel work. On the other hand, when slab is supported on all four sides and bending take place in two directions are said to be two way slab. Two way slab is a slab in which the ratio of longer side to the shorter side is less than or. The flexural reinforcement calculation for the beam strip of end span. Step 2 design forces draw panel of slab and indicate maximum design moments, shears and in plane loads, if any, per unit width of slab.

Slab shear strength two way shear check the adequacy of slab thickness for punching shear two way shear at an interior column figure 4. Bending will take place in the two directions in a dishlike form. The imposed loading on the floor is 5 knm2 and an allowance. The twoway slab s1 is supported by four beams twoway slab behaviour. One way and two way slab reinforcement in detail at sit duration.

Flat slab system is an important division of concrete floor system. However, the structural behaviors of twoway voided slabs with segmented voids have. Twoway flexural behavior of donuttype voided slabs. The two way slab s1 is supported by four beams two way slab behaviour the behavior of a two way slab is similar to that of a one way slab the only difference being that now the slab loads will be carried in both directions. Two way concrete slabs with openings i have never depreciated the role of gdansk university of technology in giving me the necessary knowledge to complete the studies. Design of isolated square and rectangular footings aci 31814. Can anyone help me with the slab rebar arrangement when.

Each single slabs are referred to as panels, if the slab is continuous over supports. In efm, live load shall be arranged in accordance with 6. Determine moments at critical sections in each direction, normally the negative moments at supports and positive moment near midspan. Reinforcement detailing of reinforced concrete slabs. Voided slab systems were developed using segmented void formers such as spherical or oval plastic balls for twoway slab applications. As a steelworker, you must be able to properly cut, bend, place, and tie reinforcing steel. Comparison of twoway slab analysis and design methods.

For better view, please read this post in landscape mode if you are on the mobile device. Understanding of drawing1 examination of drawing when construction contract is completed, the contents of the drawings are surveyed and checked before construction work. In one way slab, the ratio of longer span l to shorter span b is equal or greater than 2, i. Sandwich slabs may have the disadvantage of a larger weight compared to the ribbed ones but on the other hand, they have the advantage that their spans and supports behave in the same proper way. 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. Feb 20, 2012 rebar arrangement and construction carryout 1. Manual for design and detailing of reinforced concrete to.

Flat slab analysis, design and detailing pdf civil. The basic design procedure of a twoway slab system has five steps. And when we go back to the moon, lets go metric, ay. Slab shear strength twoway shear check the adequacy of slab thickness for punching shear twoway shear at an interior column figure 4.

Slab may be supported on walls or beams or columns. Generally, there are two types of slab which are one way and two way slabs. Secure the bars in position in such a way that concreteplacing operations will. Determine the area of steel required in the slab at critical sections for column and. Jan 11, 2017 reinforcement detailing of a slab is done based on its support conditions. Accordingly, main reinforcement is required in the two directions. Please help promote this free service tell a friend about this site. One way i would recommend is to design as twoway flat plate slab using either hand calcs or software such as csi safe. For flexural or main reinforcement, rationalised arrangements of loose bar using. Design of reinforced concrete structures ii twoway slabs. The behavior and the reinforcement of a oneway slab connected to a cantilever are described below. The structural action of a one way slab may be visualized in terms of the deformed shape of the loaded surface.

Two way slab design by direct design method as per aci 31811. Although it is a rule to survey the drawings right from the 1st page, it is common to ch. Slab rebar arrangement 1 slab rebar arrangement slab type classification 2 way slab rebar arrangement method 1way slab rebar arrangement method slab main bar arrangement type classification bent bar type union type of outer beam and slab union type of outer wall and slab ly r e b a r b a r l a p 1 1 provided is at least twice that. Manual for design and detailing of reinforced concrete to the. Aci 31599 details and detailing of concrete reinforcement. Pile supported foundation pile cap analysis and design. Slab supported directly by columns are called flat slab. The structural action of a oneway slab may be visualized in terms of the deformed shape of the.

One way slab is a slab which is supported by beams on the two opposite sides to carry the load along one direction. Calculate rebar spacing, layout and weight in a concrete slab. For twoway spanning slabs the check should be carried out on the basis of the shorter span. Figure 1 shows a rectangular slab, simply supported along its two opposite long edges and free of any support along the two opposite short edges. In two way slab, the ratio of longer span l to shorter span b is less than 2. Slab rebar arrangement 1 slab rebar arrangement slab type classification 2 way slab rebar arrangement method 1way slab rebar arrangement method slab main bar arrangement type classification bent bar type union type of outer beam and slab union type of outer wall and slab ly 2. Manual for design and detailing of reinforced concrete to september 20 the code of practice for structural use of concrete 20 contents 1. Ec2 section 8 detailing of reinforcement general rules.

A slab or panel is said to be two way slab if the ratio of longer span to the shorter span is not greater than 2 two. Reinforcement detailing of a slab is done based on its support conditions. No beam, free layout and large windows create bright and open spaces in. So, main reinforcement is provided in both direction for two way slabs. If the first slab is a twoway slab, both the behavior and the reinforcement rules are proportionate. Two way slab design by direct design method as per aci 31811, step by step procedure and limitations of direct design method for two way slab is presented. This should be acceptable because the initial footing size was chosen on the basis of twoway shear limiting. Effects of posttensioning slippage on 2way spanning concrete slabs article pdf available in advances in civil engineering 2015. Effects of posttensioning slippage on 2way spanning. In one way slab, one side is larger than the other one. Anchorage and lap splicing detailing of slabs, columns. Design of reinforced concrete structures ii two way slabs 1 1. Founded in 1904 and headquartered in farmington hills, michigan, usa, the american concrete institute is a leading authority and resource worldwide for the development, dissemination, and adoption of its consensusbased standards, technical resources, educational programs, and proven expertise for individuals and organizations involved in concrete design. Chapter 3 fabrication and placement of reinforcing steel navy bmr.