There are two types of slab classification based on the direction of bending occurs in these slabs. Oct032018 two way concrete floor slab with beams design and detailing csa a23. Difference between one way slab and two way slab system. For those who do not know what are the des ign requirements of a slab. Two way slab design by direct design method as per aci 31811.
Design procedure steps for one way slab slab design steps. Pdf babadua reinforced concrete twoway slabs subjected to. Jul 02, 2010 lecture series on design of reinforced concrete structures by prof. In two way slabs, load will be carried in both the directions. Reinforced concrete slab design and detailing guide is456. The two way slab building system is a very effective and common building system. The effective depth d of two way slabs can also be assumed using cl. Twoway concrete slab with beams spanning between supports. If playback doesnt begin shortly, try restarting your device. Simply supported one way slab a rectangular reinforced concrete slab is simplysupported on two masonry walls 250 mm thick and 3.
From the study it is considered that post tension slab is more economical than two way slab. Determine moments at critical sections in each direction, normally the negative moments at supports and positive moment near midspan. Slab supported on two sides and bending takes place predominantly in one direction only is called one way slab. The building is located in seismic zone iii on a site with medium soil. The basic design procedure of a two way slab system has five steps. There are many different methods for analysis of two way reinforced concrete slabs. Slabs are usually used in floor and roof construction.
Oneway and twoway slabs oneway slabs transfer the imposed. Click to share on facebook opens in new window click to share on twitter opens in new window click to email this to a friend opens in new window. Floor openings in twoway slabs structural engineering forum of. However, the complexity of the generalized approach. Distribute moments transverse at critical sections to column and middlestrip and if.
Analysis and design of two way slabs page 1 chapter 3. For b oth one way and two way slab with an example. In this post, we are going to explain how to calculate steel quantity for the slab. If severe deflection limits are imposed, the two way slab will be most suitable, as the introduction of even moderately stiff beams will reduce deflections more than the largest reasonable column capital is able to.
A reinforced concrete slab is a broad, flat plate, usually horizontal, with top and bottom surfaces parallel or nearly so. The first reinforced concrete design manual formerly titled aci design handbook was developed in. 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. In two way slab main reinforcement is provided along both direction. Please select the grade of concrete for twoway slab construction. A six storey building for a commercial complex has plan dimensions as shown in figure 1. Dhang, department of civil engineering, iit kharagpur. Reinforced concrete design to bs8110 structural design 1 lesson 5 5 4.
The slab has to carry a distributed permanent action of 1. Reinforcement detailing of reinforced concrete slabs. I have developed a microssoft excel software for design of a two way rcc slab. Long and short spans of a two way slab are l and l and load on. The one way and two way slab systems are the most commonly used floor system in the reinforced concrete structure. Dec 20, 2017 in this video deisgn of two way slabs has been covered using is 456.
The following example illustrates the design methods presented in the pca book simplified designreinforced concrete buildings of moderate size and height third edition. Two way rcc slab designing tool in microsoft excel developed by shankar tayal a 3rd year student of school of infrastructure, indian institute of technology, bhubaneswar. In two way slab, the ratio of longer span l to shorter span b is less than 2. Two way reinforced concrete slab design clear longer span of slab please enter the longer span. Fanella, which appeared in the october 2001 edition of structural engineer magazine. If the ratio of longer dimension of the slab panel to the shorter dimension is greater than or equal to 2 then it is designed as one way slab. The solution per ddm can be found in the two way plate concrete floor system design example. Two way rcc slab designing excel sheet civil engineering. Here the ratio of longer span of slab to the shorter span of slab is less or equals to 2. Reinforced concrete design 1 design of slab examples. For better view, please read this post in landscape mode if you are on the mobile device.
The choice between two way and beamless slabs for more normal situations is. Two way slab being supported on four sides the load will be carried in both the directions. Two way slabs page 1 of 14 the following example illustrates the design methods presented in the article timesaving design aids for reinforced concrete, part 2. Following are the rcc slab design and detailing guidelines. Rcc structures design multiple choice questions and answers pdf free download for civil students. Two way slabs have two way bending unlike one way slab. Design of slab examples and tutorials by sharifah maszura syed mohsin example 1. Twoway slab design panel select boundary condition of slab for upliftment of corners.
These slabs are constructed to provide flat surfaces, usually horizontal, in building floors, roofs or other types of structures. Analysis and design of slabs two way civil engineers pk. Design of two way slabs is 456 limit state method youtube. No redistribution is allowed when method 1 or method 2 of analysis in. Reinforced concrete, as a composite material, has occupied a. Pdf strengthening of reinforced concrete twoway slabs. According to the way loads are transferred to supporting beams and columns, slabs are classified into two types. Redistribution of 10% may be allowed when method 3 or method 4 is adopted. What is the formula for taking load from two way slab for. Slabs can be designed by direct design method known as ddm and another method for design is coefficient method which is the easier one. The one way slab is deflected in one way direction and primary reinforcement is placed in one direction whereas. Efm is the most comprehensive and detailed procedure provided by the aci 318 for the analysis and design of two way slab systems where the structure is modeled by a series of equivalent frames interior and exterior on. 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.
In two way slabs shorter direction strip carry greater %age of load. Here are the steps for the design procedure for one way slab in steps. The following example illustrates the example building. Design of reinforced concrete structures ii two way slabs 1 1. The aci 318 building code permits openings of any size in any new slab system, provided that an analysis is performed that demonstrates that both strength and. Unless otherwise noted, all referenced table, figure, and equation. Introduction in reinforced concrete construction, slabs are used to provide flat, useful surfaces. Slab resting on walls or sufficiently deep and rigid beams on all sides. According to the 1995 aci code, all two way reinforced concrete slab systems, including edge supported slabs, flat slabs, and flat plates, are to be analyzed and designed according to one unified method, such as direct design method and equivalent frame method. This is a part of his project economic design of two way rcc slabs under prof s. Corners of the two way slab lift up if the slab is not cast monolithically with the supports wallsbeams.
Determine moments at critical sections in each direction, normally the negative moments. The development of these methods was a necessity due to different causes, such as inadequate maintenance, overloading of the reinforced concrete member, corrosion of the steel reinforcement and other different situations that appeared in time. They may be supported on two opposite sides only fig. Pdf selection of economical span in rcc building researchgate. Reinforced concrete design 1 design of slab examples and. Bending will take place in the two directions in a dishlike fo. Design of reinforced concrete structures ii twoway slabs. Reinforced concrete slab design using the empirical method bridgesight solutions for the aashto lrfd bridge design specifications bridgesight software tm creators of effective and reliable solutions for the worlds bridge engineers. The two classifications are one way slab and two way slab. Design of one way and two way slabs, design of staircases. Unless otherwise noted, all referenced table, figure, and. The two way slab will deflect in a dish or saucerlike form under the action of loads. A rectangular reinforced concrete slab is simply supported on two masonry walls 250 mm thick and.
Design a simply supported rcc slab for a roof of a hall 3. For such cases flat slab with column capitals is very well suited. The basic design procedure of a twoway slab system has five steps. Generally, there are two types of slab which are one way and two way slabs.
Designing for shear in slabs when shear reinforcement is not required e. I am submitting it to you and i want students or professional engineers to download it and use it for their studies or projects. Twoway concrete floor slab with beams design and detailing. In this video deisgn of two way slabs has been covered using is 456. Design of a two way rcc slab structural engineering forum. Twoway slab analysis and design using equivalent frame method efm. No redistribution is allowed when method 1 or method 2 of analysis in section 3.
The two way slab is designed for both the directions as it bends in both directions. The reinforced concrete design manual sp1711 is intended to provide guidance and assistance to professionals engaged in the design of castinplace reinforced concrete structures. Reinforced concrete slab design using the empirical method. Lecture series on design of reinforced concrete structures by prof. Bending will take place in the two directions in a dishlike form. Reinforced concrete design to bs8110 structural design 1. The quantities of the materials are calculated and cost of construction for slabs are determined and compared. Please read the lauses mentioned in the video while solving the problem. Two way reinforced concrete slab design clear longer span of slab. Continuous beam if it is the other way, for end span with 1 end fixed and the other continuous. Two way slabs are such slabs in which the loads are shared by both the shorter and longer direction of the slab.
Oneway and twoway slabs university of asia pacific. Pdf this work investigated the flexural strength and deformation of 14 twoway concrete slabs that were reinforced in two directions with babadua. One way and twoway slabs one way slabs transfer the imposed loads in one direction only. Carbon frp strips and glass frp laminates can be used to increase the flexural capacity of two way slabs to an.
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