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. These are the direct design method presented in chap. Master of science and hereby certify that, in their opinion, it is worthy of acceptance. Bending will take place in the two directions in a dishlike form. This will appear at the top of the first page of the output. Distribute moments transverse at critical sections to column and middlestrip and if. Design of reinforced concrete structures ii twoway slabs 1 1. The method is based on the lower bound theorem of plasticity, meaning that a design based on the strip method is. 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.
For the purpose of this tutorial, enter the general title as sixspan, oneway slab. Assume partitions cannot be damaged by deflections. The program covers wide range of twoway slab systems and can be used for more complex slab layouts. Cornell university, david darwin university of kansas, charles dolan university of wyoming 3. Load transfer in a oneway slab, b twoway slab nilson fig. 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. Two way slab design by direct design method as per aci 31811.
Determine moments at critical sections in each direction, normally the negative moments at supports and positive moment near midspan. Oneway and twoway slabs university of asia pacific. The direction in which the load is carried in one way slab is called the span. In twoway slabs shorter direction strip carry greater %age of load. Reinforced concrete slab design and detailing guide is456. Generally, there are two types of slab which are one way and two way slabs. 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. I am submitting it to you and i want students or professional engineers to download it and use it for their studies or projects. Analysis of two way ribbed and waffle slabs with hidden beams. Bridge approach slab analysis and design incorporating elastic soil support presented by. Example on design of slab bridge design data and specifications superstructure consists of 10m slab, 36m box girder and 10m tgirder all simply supported. Design of concrete structures 14th edition, 2009, by arthur h. The design procedure for a uniformly loaded oneway reinforced slab can be divided in the following steps.
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. A monolithic reinforced concrete floor is to be composed of rectangular bays measuring, as shown. Click to share on twitter opens in new window click to share on facebook opens in new window related posts. This example goes through the design of a simplysupported oneway slab on beams. Uhpc link slab design uhpc workshop june 28th, 2017 jim scarlata, p. Bss090119991 abstract this design example illustrates the empirical design method for composite concrete bridge decks specified in article 9. Therefore, primary reinforcement is presented in both directions for resisting the loads.
Design of a two way rcc slab structural engineering. Chapter 3 design of rectangular beams and oneway slabs. 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. 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. Interior bay dimensions 20 24 this example is to be used for educational purposes only. But, with proper application and enough safety factor yield line method. 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. 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.
Rectangular beams and oneway slabs page 3 of 9 design of rectangular beams and oneway slabs continued a. 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. Lecture 12 equivalent frame method linkedin slideshare. The basic design procedure of a twoway slab system has five steps. 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. C 5 is the slope correction coefficient co is the consolidation correction coefficient as an example. Design of reinforced concrete structures ii twoway slabs. The dimensions of an interior bay are shown in figure 1. Use the aci 318 direct design method to design an interior bay of a flat plate slab system of multi bay building. 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. Slab shear strength twoway shear check the adequacy of slab thickness for punching shear twoway shear at an interior column figure 4. The output of the program for the slab in the example is shown in the following pages. Title reinforced concrete slab design using the empirical method publication no. Hollow blocks made of lightweight concrete or other materials are arranged between the ribs or the voids between ribs. The following example illustrates the example building. Twoway slabs have two way bending unlike oneway slab.
Only the design of slab bridge will be used for illustration. Hillerborgs strip method of design 1, 2 is a powerful and versatile technique for designing twoway reinforced concrete slabs and plates. Best is subjective, so i will give my opinion here. Following are the rcc slab design and detailing guidelines. Civilax is the knowledge base covering all disciplines in civil engineering. Reinforced concrete slab design using the empirical method. Okay, i know it is based on upper bound thorem and the solution might be unsafe. 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. Notes author staff bridgesight software sponsor bridgesight software.
Two way reinforced concrete slab design spreadsheet. The ratio of the total costs was found to be within the range 1. Oneway spanning slabs should be treated as beams of unit width and chapter 2 should be followed except for minimum shear reinforcement. Two way reinforced concrete slab design spreadsheet working stress design coefficient method download spreadsheet. Plan view of floor system assume partitions will not be damaged by deflections. 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. Analysis and design of the slab similar to design of simply supported beam as indicate in the previous chapter.
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. In two way slab, load is delivered in both the directions. I have developed a microssoft excel software for design of a two way rcc slab. 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. Beams of width and depth are provided on all column lines. Oneway slab design spreadsheet civil engineering community. This will appear at the top of the each subsequent page of the output. 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. 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. One way slabs are those supported continuously on the two opposite sides so that the load sare carried along one direction only.
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