The service live load is 100 psf and 4000 psi concrete is specified for use with steel with a yield stress equal to 60000 psi. Slab with reinforcement with yield stress, f y, exceeds 60,000 psi measured at a yield strain of 0. Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. The design procedure for a uniformly loaded oneway reinforced slab can be divided in the following steps. Design of reinforced concrete structures ii twoway slabs. Reinforced concrete design 1 design of slab examples and. The finite element method is commonly used to design the reinforcement in concrete slabs. Anchoring of link slab the portion of the link slab beyond the unbonded length is used to anchor it into the concrete deck slab. For the purpose of this tutorial, enter the general title as sixspan, one way slab. Effective span of slab shall be lesser of the two 1. Determine moments at critical sections in each direction, normally the negative.
Cornell university, david darwin university of kansas, charles dolan university of wyoming 3. Task is to derive a split factor c x for twoway slab with supports in direction x as simplesimple ss and in direction y o as simplefixed sf. Master of science and hereby certify that, in their opinion, it is worthy of acceptance. Design of a two way rcc slab structural engineering. The oneway slab is deflected in one way direction and primary reinforcement is placed in one direction whereas. One way and two way slabs one way slabs transfer the imposed loads in one direction only. Dissatisfaction with results of previously required procedures of analysis and design for two way slab beam systems was the original reason for the massive research upon two way slab systems begun about 1955. I am submitting it to you and i want students or professional engineers to download it and use it for their studies or projects.
Reinforced concrete slab design and detailing guidelines for depth of slab, loads on slab, reinforcement guide for one way and two way slabs as per is 456. My graduation project with my mate ghassan faris, a two way ribbed slab of clear span of 18 x 25 m was designed by safe 2014, the building is 3storey concrete. Tn342 design example 2way mondada 093090 adapt corporation. The dimensions of an interior bay are shown in figure 1. The ratio of the total costs was found to be within the range 1. Chapter 3 design of rectangular beams and oneway slabs 12. Assume partitions cannot be damaged by deflections. Summary and comparison of twoway slab design results. All available load test results indicated that the flat plate or flat slab was a most efficient design with an adequate safety factor.
Aci 31811 code provides two methods for two way slab design one of which is direct design method. Analysis and design of the slab similar to design of simply supported beam as indicate in the previous chapter. Nov 27, 20 one way slab design criteria with design example according to aci code slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Beams of width and depth are provided on all column lines. Design of reinforced concrete structures ii two way slabs 1 1. No certain method can be found in the design codes or references for designing twoway slabs subjected to concentrated loads. A monolithic reinforced concrete floor is to be composed of rectangular bays measuring, as shown. It is divided into 25 panels with a panel size of 25 ft x 20 ft.
The direction in which the load is carried in one way slab is called the span. This example goes through the design of a simplysupported oneway slab on beams. Analysis of two way ribbed and waffle slabs with hidden beams. In two way slabs shorter direction strip carry greater %age of load. Slab shear strength twoway shear check the adequacy of slab thickness for punching shear twoway shear at an interior column figure 4. For uniformly distributed loads of w per square foot of the slab, each strip acts approximately like a simple beam uniformly loaded by its share of w. In this example deflection will be calculated and checked to satisfy project. Load transfer in a oneway slab, b twoway slab nilson fig. Although the major reinforcement in one way slab span is in the short direction, yet at the corner, the moment is actual supported by beams at both directions. Rectangular beams and oneway slabs page 3 of 9 design of rectangular beams and oneway slabs continued a. Oneway and twoway slabs university of asia pacific.
For the purpose of this tutorial, enter the general title as sixspan, oneway slab. The method is based on the lower bound theorem of plasticity, meaning that a design based on the strip method is. One way slabs are those supported continuously on the two opposite sides so that the load sare carried along one direction only. The design procedure for a uniformly loaded one way reinforced slab can be divided in the following steps. A reinforced concrete slab is built integrally with its supports and consists of equal span of 15 ft. Bridge approach slab analysis and design incorporating elastic soil support presented by. The concrete deck slab in this region shall be roughened to amplitude of 12. Ce 433, fall 2006 slab design example 1 6 design a oneway slab for an exterior bay of a multistory office building using the information specified below. The following example illustrates the design methods presented in the pca book simplified design reinforced concrete buildings of moderate size and height third edition. In twoway slabs shorter direction strip carry greater %age of load.
This will appear at the top of the each subsequent page of the output. The one way slab is deflected in one way direction and primary reinforcement is placed in one direction whereas. Hillerborgs strip method of design 1, 2 is a powerful and versatile technique for designing twoway reinforced concrete slabs and plates. Twoway slabs have two way bending unlike oneway slab. Uhpc link slab design uhpc workshop june 28th, 2017 jim scarlata, p. If you continue browsing the site, you agree to the use of cookies on this website. The basic design procedure of a two way slab system has five steps. Concrete strength is and steel yield strength is f y 40,000 psi. In this example, the latter option will be used to achieve better understanding for the design of two way joist slab often called two way ribbed slab or waffle slab. The output of the program for the slab in the example is shown in the following pages. Design of concrete structures 14th edition, 2009, by arthur h.
The size, spacing, and type should match that of the adjacent concrete deck. Time saving design aids two way slabs page 6 of 14 the pca computer program pcaslab can be used to expedite the design of different slab systems. Two way slabs have two way bending unlike one way slab. 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. One way and two way slab design aspect online civilforum. These are the direct design method presented in chap. Following are the rcc slab design and detailing guidelines. Reference 5 focused on analysis of twoway ribbed slabs with. Slab design reading assignment chapter 9 of text and, chapter of aci31802. Design of an oneway reinforced concrete slab with rcsolver software program according to eurocode 2 specifications. For a sample output refer to twoway flat plate concrete floor slab design example.
Design of reinforced concrete structures ii twoway slabs 1 1. Unless otherwise noted, all referenced table, figure, and equation. L center to center distance between the support b depth of slab. We assume that the verandah slab is a two way slab instead of one way slab in order to calculate mb,neg now, using moment coefficient method for analysis. The composite slab which has to be placed on a conference hall has been selected for this project. Accordingly, main reinforcement is required in the two directions. Example design of two way edgesupported solid slab. Hillerborgs strip method of design 1, 2 is a powerful and versatile technique for designing two way reinforced concrete slabs and plates.
One way and two way slab design aspect the slab provides a horizontal surface and is usually supported by columns,beams or walls. Generally, there are two types of slab which are one way and two way slabs. Reference 5 focused on analysis of two way ribbed slabs with. Design of a two way rcc slab structural engineering forum. Slab design, bs 8110 slab design, how to determine ultimate load for slabs, how to check for deflection in slabs, how to calculate for dead load, how to calculate for lever arm, basics of slab design, how can i design a 2 way spanning slab.
Twoway concrete floor slab with beams design and detailing design the slab system shown in figure 1 for an intermediate floor where the story height 12 ft, column crosssectional dimensions 18 in. Recommendations for finite element analysis for the design of. Twoway concrete slab with beams spanning between supports. This will appear at the top of the first page of the output. Design of slab examples and tutorials by sharifah maszura syed mohsin example 2. I have developed a microssoft excel software for design of a two way rcc slab. Abstractdesigning twoway slabs under transverse concentrated loads is one of the challenges in designing such structures. Distribute moments transverse at critical sections to column and middlestrip and if. In order to simplify the analysis and to be able to use the superposition principle for evaluating the effect of load combinations, linear analysis is generally adopted even though concrete slabs normally have a pronounced nonlinear response. 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.
Dissatisfaction with results of previously required procedures of analysis and design for twoway slabbeam systems was the original reason for the massive research upon twoway slab systems begun about 1955. Next, select the structural system as one way slab. Two way reinforced concrete slab design spreadsheet working. Analysis and design of slabs two way civil engineers pk. Gallares street, tagbilaran city bohol, philippines 3600 tel. In this project, the design of composite slab and connection with the beam using shear connectors have been done using insdag design manual based on assumptions of eurocode4 and is.
Twoway joist concrete slab floor waffle slab system. Examples of the portion of slab to be included with the beam under. Time saving design aids twoway slabs page 6 of 14 the pca computer program pcaslab can be used to expedite the design of different slab systems. Reinforced concrete slab design and detailing guide is456. The basic design procedure of a twoway slab system has five steps. The slab is supported on beams of size 225 x 500 mm spaced at 4.
Whatever may be the width of the slabs it should always be designed for a width of equal to one metre and the same design should be adopted for the rest of the slab. However, plastic method can be the best method for designing such cases of twoway slabs. Slab is a common term used to describe the structural elements such as floors and roofs where the thickness of the element is very small compared to the length and. Direct design method ddm for slab systems with or without beams loaded only. The program covers wide range of twoway slab systems and can be used for more complex slab layouts. Twoway flat plate concrete floor system design structurepoint. They may be supported on two opposite sides only fig. In this article, it is assumed that slab thickness is determine but calculation of column and middle strips is explained. Bending will take place in the two directions in a dishlike form. The program covers wide range of two way slab systems and can be used for more complex slab layouts. Load transfer in a one way slab, b two way slab nilson fig. Plan view of floor system assume partitions will not be damaged by deflections.
Two way slab design by direct design method as per aci 31811. Task is to derive a split factor c x for two way slab with supports in direction x as simplesimple ss and in direction y o as simplefixed sf. This example is to be used for educational purposes only. Continuous one way slab figure 1 shows a clear area of 12 m x 8. Jul 22, 2015 my graduation project with my mate ghassan faris, a two way ribbed slab of clear span of 18 x 25 m was designed by safe 2014, the building is 3storey concrete. Chapter 3 design of rectangular beams and oneway slabs. For economical design of similar structures a smaller slab thickness leading to values between 60% to 80% of balanced selfweight is generally selected. Use the aci 318 direct design method to design an interior bay of a flat plate slab system of multi bay building. Direct design method design of two way floor system for slab with beams figure1 shows a twoway slab floor with a total area of 12,500 sq ft. Check the applicable joist dimensional limitations as follows. The concrete deck slab in this region shall be roughened to amplitude of 1 2. Oneway and twoway slabs oneway slabs transfer the imposed.
Determine moments at critical sections in each direction, normally the negative moments at supports and positive moment near midspan. Jul 10, 2017 this example goes through the design of a simplysupported one way slab on beams. A single slab with oneway reinforcement rebars will be analyzed with rcsolver. Design of two way slab example pdf flat slab design pdf bs 8110 concrete design for slab post tension slab slab on grade foundation how to calculate formwork for slab how to pour a concrete slab concrete beam and slab bridge how to pour a 26x36 concrwte concrete slab operation management 9th edition myomlb nigel slab usercentered design, activitycentered design, and goaldirected design. One way slab design criteria with design example according to aci code slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Two way concrete floor slab with beams design and detailing design the slab system shown in figure 1 for an intermediate floor where the story height 12 ft, column crosssectional dimensions 18 in. For 1m slab width, moment, shear force, oneway continuous slab for continuous slab, moment and shear force can be obtained from table 3. Oneway slab is the most basic and common type of slab.
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