Slab shear strength twoway shear check the adequacy of slab thickness for punching shear twoway shear at an interior column figure 4. Bending will take place in the two directions in a dishlike form. Analysis and design of the slab similar to design of simply supported beam as indicate in the previous chapter. Design of reinforced concrete structures ii twoway slabs.
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. Cornell university, david darwin university of kansas, charles dolan university of wyoming 3. 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 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. Bridge approach slab analysis and design incorporating elastic soil support presented by.
Use the aci 318 direct design method to design an interior bay of a flat plate slab system of multi bay building. In twoway slabs shorter direction strip carry greater %age of load. In two way slab, load is delivered in both the directions. Therefore, primary reinforcement is presented in both directions for resisting the loads. Plan view of floor system assume partitions will not be damaged by deflections.
Chapter 3 design of rectangular beams and oneway slabs. Slab with reinforcement with yield stress, f y, exceeds 60,000 psi measured at a yield strain of 0. This will appear at the top of the each subsequent page of the output. 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. Only the design of slab bridge will be used for illustration. It is recommended to create the design of slab with the use of excel sheet as the process will be very simple and lots of time will be saved. Define the term slab, one way slab, two way slab, shrinkage and temperature reinforcement, main reinforcement. All available load test results indicated that the flat plate or flat slab was a most efficient design with an adequate safety factor. C 5 is the slope correction coefficient co is the consolidation correction coefficient as an example. Uhpc link slab design uhpc workshop june 28th, 2017 jim scarlata, p.
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. Two way reinforced concrete slab design spreadsheet working stress design coefficient method download spreadsheet. The ratio of the total costs was found to be within the range 1. Oneway and twoway slabs university of asia pacific. Example on design of slab bridge design data and specifications superstructure consists of 10m slab, 36m box girder and 10m tgirder all simply supported. Hollow blocks made of lightweight concrete or other materials are arranged between the ribs or the voids between ribs. Oneway ribbed slabs since resistance of concrete in tension is too small compared with that in compression, concrete in the tension zone may be gathered in regularly spaced ribs cast monolithically with topping slab on top of these ribs. Design of reinforced concrete structures ii twoway slabs 1 1. Reinforced concrete slab design using the empirical method. 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. Analysis of two way ribbed and waffle slabs with hidden beams. These are the direct design method presented in chap. Generally, there are two types of slab which are one way and two way slabs.
Twoway slabs have two way bending unlike oneway slab. Beams of width and depth are provided on all column lines. The oneway slab is deflected in one way direction and primary reinforcement is placed in one direction whereas. A monolithic reinforced concrete floor is to be composed of rectangular bays measuring, as shown. Analysis and design of slabs two way civil engineers pk. For 1m slab width, moment, shear force, oneway continuous slab for continuous slab, moment and shear force can be obtained from table 3. Design examples look at example 7 design of a flat plate floor without spandrel beams direct design method look at example 9 design of a. Assume partitions cannot be damaged by deflections.
Hillerborgs strip method of design 1, 2 is a powerful and versatile technique for designing twoway reinforced concrete slabs and plates. Civilax is the knowledge base covering all disciplines in civil engineering. 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. Oneway slab design spreadsheet civil engineering community. Rectangular beams and oneway slabs page 3 of 9 design of rectangular beams and oneway slabs continued a. Reinforced concrete slab design and detailing guide is456. The dimensions of an interior bay are shown in figure 1. 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. I have developed a microssoft excel software for design of a two way rcc slab. This will appear at the top of the first page of the output. Bss090119991 abstract this design example illustrates the empirical design method for composite concrete bridge decks specified in article 9.
Notes author staff bridgesight software sponsor bridgesight software. The basic design procedure of a twoway slab system has five steps. University of engineering and technology peshawar two way slab equivalent frame method efm introduction this 3d frame is converted to a 2d frame by taking effect of stiffness of laterally present members slabs and beams. The following example illustrates the example building. Two way reinforced concrete slab design spreadsheet. Load transfer in a oneway slab, b twoway slab nilson fig. Lecture 12 equivalent frame method linkedin slideshare. But, with proper application and enough safety factor yield line method. The output of the program for the slab in the example is shown in the following pages. Design of a two way rcc slab structural engineering. Oneway spanning slabs should be treated as beams of unit width and chapter 2 should be followed except for minimum shear reinforcement. Best is subjective, so i will give my opinion here. 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.
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. Interior bay dimensions 20 24 this example is to be used for educational purposes only. Title reinforced concrete slab design using the empirical method publication no. Okay, i know it is based on upper bound thorem and the solution might be unsafe. 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. 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. Two way slab design by direct design method as per aci 31811. 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.
Distribute moments transverse at critical sections to column and middlestrip and if. The design procedure for a uniformly loaded oneway reinforced slab can be divided in the following steps. 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. I am submitting it to you and i want students or professional engineers to download it and use it for their studies or projects. One way slabs are those supported continuously on the two opposite sides so that the load sare carried along one direction only.
Click to share on twitter opens in new window click to share on facebook opens in new window related posts. For the purpose of this tutorial, enter the general title as sixspan, oneway slab. Following are the rcc slab design and detailing guidelines. The method is based on the lower bound theorem of plasticity, meaning that a design based on the strip method is. Design of concrete structures 14th edition, 2009, by arthur h. This example goes through the design of a simplysupported oneway slab on beams. The program covers wide range of twoway slab systems and can be used for more complex slab layouts. The direction in which the load is carried in one way slab is called the span. Master of science and hereby certify that, in their opinion, it is worthy of acceptance.
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