# Two Way Slab Design Example Pdf

Refer to Fig. Slabs are usually used in floor and roof construction. Modeling the building and obtaining the modal properties (mode shapes and fundamental. Design Of Reinforced Concrete Structures ii Two-Way Slabs 1 1. The two classifications are one-way slab and two-way slab. Tests on three model slabs incorporating minimum reinforcement ratio, minimum depth and maximum bar spacing permitted by the Australian Concrete Structures Code showed satisfactory behaviour at service loads and ultimate loads despite the fact that bending. txt) or view presentation slides online. This problem is. The slab has to carry a distributed permanent action of 1. One way slabs are such slabs in which the loads are shared only by the shorter direction of the slab. The slabs having supports on all sides acts as two way. A circular slab is a two-way slab. In flat-plate floors, slab-column connections are subjected to high shear stresses produced by the transfer of axial loads and bending moments between slab and columns. Cantilever Slab Design Calculation & Procedure Design of cantilever slab to Eurocode 2 Span of slab 1. Effective depth d= Span /((L/d)Basic x modification factor) For obtaining modification factor, the percentage of steel for slab can be assumed from 0. There are two types of slab classification based on the direction of bending occurs in these slabs. Unformatted text preview: Design of TwoTwo-Way Slabs Flat Plate Flat Slab One-Way One Way Joist Two-Way Joist Slab with Beams Steps in Slab Design • Choose the layout and type of slab: Architectural or construction consideration • Choose the slab thickness: Adequate for deflection/shear • Choose Ch th the method th d ffor d design: i Di Directt Design Method, Elastic frame analysis. Two-Way Slab Design Based on ACI 318-11 using Finite Element Method. 0 k/ft M, kip-ft 38. The 2012 edition of the Reinforced Concrete Design Manual [SP-17(11)] was developed in accordance with the design provisions of ACI 318-11, and is consistent with the format of SP-17(09). The direct design method is an approximate method used to analyze two way slabs. The PDF covers the following topics: Properties of flat slab. PT Designer is a computer program for the design and analysis of linear post-tensioned concrete floor systems. Here ratio of longer span of slab to the shorter span of slab is greater than 2. Here are the steps for the Design Procedure for One Way Slab in steps. 1—Minimum slab thickness. Direct design method is used for the structural analysi s and. Excel Sheet to Design Slab - One Way and Two Way > Share: Rate: Previous Computational Methods for Fluid Dynamics by Ferziger. In this paper the cost optimization of reinforced concrete two-way slabs under uniformly distributed load with the nonlinear programming approach has been presented and it is a continuation of the. e Longer span (l)/Shorter span (b) < 2. 1 Two Way Slab Problem Statement: Use the ACI 318 Direct Design Method to design an interior bay of a flat plate slab system of multi bay building. tensioned slab structures, especially post-tensioned flat slabs*. Slab design Example 02 Design of simply supported slab (Two way spanning) =1. Bending will take place in the two directions in a dish-like form. Two-Way Concrete Floor Slab with Beams Design and Detailing. xlsm Member Design - RC Two Way Spanning Slab 03-09-15 CONSULTING E N G I N E E R S All Beams Beam y Sag Beam y Hog Beam x Sag Beam x Hog Made by Date Chd. 101,234 at University of Duhok. Direct design method, that could have been named the direct analysis method because it determines or prescribes moments for different parts of the slab panel without the need to conduct structural analysis, is explained in the following sections. flat slabs and pad foundations Shear There are three approaches to designing for shear: • When shear reinforcement is notrequired e. c) Limiting crack width under increased (design/service) loads or sus-tained loads. 13: Bending moment coefficient for simply supported two-way slab (Ref. usually one and two-way spanning slabs • Punching shear –e. behavior of the software has not changed for this example. and slab live load: 2. Rooms (two way slabs) are continuous with verandah (one way slab). College of Engineering. Two-way slabs carry load in two directions. Practical Yield Line Design 2 Notation Symbols The symbols used in this publication have the following meaning: Symbol Description Units A Area of column cross-section m2 a, b, c Plan dimensions of slab supported on several sides m. 9 provides A. SHEAR DESIGN IN FLAT PLATES AND FLAT SLABS When two-way slabs are supported directly by columns, as in flat slabs and flat plates, or when slabs carry concentrated loads, as in footings, shear near the columns is of critical importance. Design of Slab (Examples and Tutorials) by Sharifah Maszura Syed Mohsin Example 2: Continuous one way slab Figure 1 shows a clear area of 12 m x 8. A tendon may contain one or more seven-wire strands. Design of Two-Way Floor Slab System Comparison of One-way and Two-way slab behavior One-way slabs carry load. The first stage of the design is finding the bending moment of the slab panels. Effective depth of slab in y-direction d y = 250 - 25 - (16/2) = 217 mm. Types of Slabs: 1. However main reinforcement bar and distribution bar. CEE 461: Reinforced Concrete Design, slide 7-11 Example: Slab Design 20' 20' Plan View a Section "a" - "a" Design a one-way slab to resist a live load of 60 psf. 3 STEP-BY-STEP DESIGN PROCEDURE FOR SLABS Step 1 Analysis Carry out analysis (follow Section 3. 1 and rating requirements as stated in 17. So, main reinforcement is provided in both direction for two way slabs. 10m (min) compacted 24 dia. This paper deals with the problem of optimum design of reinforced concrete (twoway ribbed) waffle slabs using genetic algorithms. The Dimensions of an interior bay are shown in Figure 1. Sachpazis Date 18/01/2014 Chk'd by Date App'd by 1 FLAT SLAB DESIGN TO BS8110:PART 1:1997 Slab geometry Span of slab in x-direction; Span x = 7200 mm Span of slab in y-direction; Span y = 7200 mm. input cells automatically cross out invalid data 3. Design of Waffle Slab (without beams) by Direct Design Method 32 32 32 C 1 C 2 C 3 C 4 132 C 5 C 6 C 7 C 8 32 (S (S(S 22 3 7 C 9 C 10 C 11 C 12 32 8 11 B 1210 BB C 13 C 14 C 15 C 16 16. The service live load is 100 psf, and 4000 psi concrete is specified for use with steel with a yield stress equal to 60,000 psi. Reference [5] focused on analysis of two-way ribbed slabs with. A system where a two way slab is continuous with a one way slab or vice versa is called a mixed slab system. This method was provided in the American Concrete Institute (ACI) in 1963 to design two-way slabs carried by steel beams, deep beam, or walls. Determination of Two way slab thickness: Case 1 : interior and edge beams are exist. Yield strength of reinforcement = 500 Mpa. 101,234 at University of Duhok. 75 2 (18 14) ( ) 248. 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. 7 12 A Tributary u ft2 V q 0. 00075tc(12), where tc is the concrete cover. 5 Building Plan Assume S = (32 + x/2) , Building spans = (S, S, S) by (S, S, S) Design of Waffle Slab. Shorter direction steel will be placed near the outer edge to get more “d” means more lever arm to get more flexural capacity. Brown' (pdf) About The Author. ACI 318 provides two alternative methods for designing two-way slabs for concrete, The equivalent frame method? (EFM) and the direct design method (DDM). Inroduction When the ratio (L/S) is less than 2. 2: Behavior of Two way slab. Joint efforts by researchers, design engineers and For example, a post-tensioned 10 in cost between reinforced and post-tensioned concrete flat slabs. CE 433, Fall 2006 Slab Design Example 1 / 6 Design a one-way slab for an exterior bay of a multi-story office building using the information specified below. pdf - Free download Ebook, Handbook, Textbook, User Guide PDF files on the internet quickly and easily. Where: : is the largest clear distance in the longest direction of panels. 1 Introduction A slab is structural element whose thickness is small compared to its own length and width. Self weight = 200x25x10. For flat plates and slabs the column connections can vary between: 5. Slabs are primarily categorized as either one way or two ways. Rectangular Beams and One-way Slabs Page 3 of 9 Design of Rectangular Beams and One-way Slabs (Continued) a = β1 c Where β1 = 0. Equilibrium frame method. Design example: a simple two-way post-tensioned plate for. l-Purpose and scope Consistent with the mission of ACI Committee 360, this report presents state-of-the-art information on the design of slabs on grade. The terms are used interchangeably. Next Review on 'Calculations for Machine Design by Thomas H. flat slabs. This spreadsheet performs an analysis and design of two-way spanning reinforced concrete slab. 3 of ACI 318 allows the use of shear reinforcement for slabs and footings in the form of bars, as in the vertical legs of stirrups. Inroduction When the ratio (L/S) is less than 2. 3 F is the total design ultimate load on the strip of slab between adjacent columns considered (1. 8 CHAPTER 8: DESIGN OF ONE-WAY SLABS 8. In two way slab, the ratio of longer span (l. Chapter 18 - Concrete Slab Structures January 2019 18-8 18. 2—Deflection analysis. Design of Slab(Two Way) Excel Sheet. The following example illustrates the design methods presented in ACI 318-05 and IBC 2003. Reinforced Concrete Buildings Series Design Booklet RCB-2. Accordingly, main reinforcement is required in the two directions. One-way slabs:. Design Of Two Way Slab Example Pdf. Others Types of slabs Figure: Grid or Waffle slab One way slab Two way slab. When a rectangular slab is supported on all the sides and the length-to-breadth ratio is less than two, it is considered to be a two-way slab. flat slabs and pad foundations Shear There are three approaches to designing for shear: • When shear reinforcement is notrequired e. For a two way slab the ratio of ly/lx shall be ≤ 2. No certain method can be found in the design codes or references for designing two-way slabs subjected to concentrated loads. A2-Slab thickness design by WRI method A3-Design examples using COE charts A4-Slab design using post-tensioning A5-Shrinkage-compensatingconcreteexamples CHAPTER l-INTRODUCTION l. Part Three is an example-intensive course, with key concepts introduced Fundamentals of Post-Tensioned Concrete Design for Buildings - Part One. 1 allows other methods if they meet certain requirements. Storey number Storey numbers are given to the portion of the building between two successive grids of beams. all milld steel reinforcement shall conform to astma-15-62-2t for reinforcing bars 12 ; 280. D = 130 mm d = 105 mm Loads on slab Self weight of slab = 3. Design of Slab (Examples and Tutorials) by Sharifah Maszura Syed Mohsin Example 2: Continuous one way slab Figure 1 shows a clear area of 12 m x 8. 1 Introduction A slab is structural element whose thickness is small compared to its own length and width. The program is developed around the robust computational core of two popular programs – PTData. • This condition occur when the slabs are connected monolithically with support. Download: BS 8110 CONCRETE DESIGN FOR SLAB. Unless otherwise. This effect is neglected as a safe estimate. 13 and the Elastic Frame Method presented in this chapter. In addition, A23. OF TWO-WAY SLABS BY GERALD C. Slabs are mainly of two types; either one way or two way. In flat-plate floors, slab-column connections are subjected to high shear stresses produced by the transfer of axial loads and bending moments between slab and columns. Beams of width and depth are provided on all column lines; thus the clear-span dimensions for the two-way slab panels are. • In any span, the max cable sag, zd depends on the concrete cover requirements and the tendon dimensions. CE 433, Fall 2006 Slab Design Example 1 / 6 Design a one-way slab for an exterior bay of a multi-story office building using the information specified below. flat slabs and pad foundations Shear There are three approaches to designing for shear: • When shear reinforcement is notrequired e. * the design moments in the edge panel may have to be adjusted according to 3. txt) or view presentation slides online. A tendon is defined as sheathing (duct), the strand(s) within it and the corrosion inhibiting grease or grout filling its voids. Definition: 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. Two edge supported slab is always one-way. In two way slab, the ratio of longer span (l) to shorter span (b) is less than 2. pdf from CIVIL ENG. Complete Analysis & Design of a Slab on Grade Structure - Analyses uniform thickness finite Slab on Grade with free ends, supported by a vertical subgrade modulus and subjected to a Wall Load, Point Load and Uniform Pressure. That is, the load factor at. Static Equilibrium of Two-Way Slabs Total Moment in both beams Full load was transferred east-west by the planks and then was transferred north-south by the beams; The same is true for a two-way slab or any other floor system. Deep ribs, the concrete and steel quantities are relative low Expensive formwork expected. , interior beam dimensions = 14 in. Inroduction When the ratio (L/S) is less than 2. So, main reinforcement is provided in both direction for two way slabs. by EF Date 20/08/2014 Chk'd by EF Date App'd by Date RC SLAB DESIGN (BS8110:PART1:1997) TEDDS calculation version 1. The mesh designated 6 x 6 - W2. Latifee Question: Define the term slab, one way slab, two way slab, Shrinkage and temperature reinforcement, main reinforcement. 2 Design Data. Steel will be more in shorter direction. Definition: 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. The coefficient method may be the simplest, easiest and the quickest approach for the design of two-way slab supported by edge beam on all slab sides. Direct design method, that could have been named the direct analysis method because it determines or prescribes moments for different parts of the slab panel without the need to conduct structural analysis, is explained in the following sections. and Design of Residential Slabs-on-Ground, BRAB Report #33. PARTITIONING A TWO-WAY SLAB Size of the Model Edge Restraint Springs • •. The integral wearing surface is considered in the weight calculations. This is because it's length to width ratio is (Long/Short) not big enough for loads to travel in the short direction onl. Accurately determining the moments on a two-way slab is typically accomplished by finite element computer analysis. Chapter 18 – Concrete Slab Structures January 2019 18-8 18. 20 TWO-WAY SLABS Service (final) stresses Tension stress as multiple of (f'c)^1/2. Two edge supported slab is always one-way. Chapter 18 - Concrete Slab Structures January 2019 18-8 18. tool for the analysis and design of concrete slabs. The procedure of the design of two-way slabs will have all the six steps mentioned in sec. The slab looses the contact over some region. 1 Introduction A slab is structural element whose thickness is small compared to its own length and width. ft-k 8 2 2 1 l wlM 86. If the proportion of longer dimension of the slab panel to the shorter dimension is more than or equivalent to 2 then it is defined as one way slab. The terms are used interchangeably. Now, in Part Two, we will follow design examples of two of the structural systems commonly used in buildings and parking structures, namely a one-way continuous slab and a two-span beam. 3 in2, respectively as shown on the next page figure. For lower loads they can have constant. Design the slab, following the provisions of the ACK Code. The Coefficient Method is a method of designing two-way slabs that are supported by edge beams. 13 and the Elastic Frame Method presented in this chapter. and deflects in the form of dish or a saucer is called two way slabs. 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. Download: BS 8110 CONCRETE DESIGN FOR SLAB. Matthew Stuart, P. For the Direct Design Method moments are found using a simplified. Economic Concrete Frame Elements to Eurocode 2 Pictorial index ii Symbols iv 1 Introduction 1 2 Using the charts and data 2 3 In-situ concrete construction 24 3. In flat-plate floors, slab-column connections are subjected to high shear stresses produced by the transfer of axial loads and bending moments between slab and columns. The slab spans in both […]. Cantilever slab is always one-way. Section 11. BS 8110: Part 1: 1997) - Two-way Restrained Slab - Table 3. The two classifications are one-way slab and two-way slab. Slab thickness of 7 in. INTRODUCTION In reinforced concrete construction, slabs are used to provide flat, useful surfaces. If slab is supported on all four sides and R = (Shorter side / Longer side) < 0. The mesh designated 6 x 6 - W2. l-Purpose and scope Consistent with the mission of ACI Committee 360, this report presents state-of-the-art information on the design of slabs on grade. 61m -For half middle strip: b= 3. Previously known as Method 3 of the 1963 ACI Code. 1(1) Crack Control of Slabs Part 1: AS 3600 Design 7. Apr 25, 2020 - PPT - Design of Two way Slab Civil Engineering (CE) Notes | EduRev is made by best teachers of Civil Engineering (CE). example and guide for modeling a 2D post-tensioned two-way slab frame in the PT mode of the program. In two-way slabs shorter direction strip carry greater %age of load. View Design of two-way slabs(D. One-way slab design. usually one and two-way spanning slabs • Punching shear -e. Effective depth of slab in y-direction d y = 250 - 25 - (16/2) = 217 mm. TN404_slab_shear_050611 SHEAR DESIGN IN FLOOR SLABS1 Bijan O Aalami2 1 - ONE-WAY AND TWO-WAY SHEAR Tests have shown that concrete exhibits greater resistance to shear, when the geometry of its support is square, and of about the same dimensions as slab thickness Fig. 35 m in all other stories. Required reinforcement is displayed in a very. 3—Crack control in reinforced two-way action structural slabs and plates. Slab thickness: 14 cm. 25 Kn/m Floor finish = 2 Kn/m Filling load = 3. In two way slabs, load will be carried in both the directions. Minimum Depth of 2-Way Slab for Deflection Control. Take this example : ABCD is a two way slab ( L/B <2 ) Assume: Dead load of slab : 0. Two way slab 1. Step 2 Design forces Draw panel of slab and indicate maximum design moments, shears and in-. The integral wearing surface is considered in the weight calculations. Dutta , IIT Bhubaneswar. 1 and rating requirements as stated in 17. flat slabs. 6 Design of Two-way Slabs. According to the way loads are transferred to supporting beams and columns, slabs are classified into two types; one-way and two-way. In this video deisgn of two way slabs has been covered using IS 456. To see their result for this slab we will find the load factor, λ, to cause failure. 2 Example 1: Ultimate Behavior of One-Way Spanning Slab Linear Elastic Analysis Methods such as moment distribution are linear elastic methods. Rectangular Beams and One-way Slabs Page 3 of 9 Design of Rectangular Beams and One-way Slabs (Continued) a = β1 c Where β1 = 0. Design Of Two Way Slab Example Pdf. In addition to the recommended procedures, other methods are described for the sake of completeness and to compare different methods of design. M , W*L 2 /8 = 6. middle strips, similar to those used in conventionally reinforced two-way slabs. Example: Generally all the Cantilever slabs are one Way slab. 1 allows other methods if they meet certain requirements. Inroduction When the ratio (L/S) is less than 2. Linear supports: a) column-beam support a) b) b) column-wide beam (dropped slab strip) support Point-like supports of flat slabs c) d) c) column (without column head) d) column with fungiform column head. 2—Deflection analysis. DESIGN OF FLAT SLABS. This system consist of both one way and two way slabs. The ratio of the total costs was found to be within the range (1. INTRODUCTION In reinforced concrete construction, slabs are used to provide flat, useful surfaces. txt) or view presentation slides online. practice, many slabs do not meet these restrictions, for example for round or triangular slabs, slabs with large openings, slabs supported on two or three edges only (as shown in fig. 75 Kn/m Bending Moment B. Previously known as Method 3 of the 1963 ACI Code. Distribute moments transverse at critical sections to column and middle-strip and if. Slabs are usually used in floor and roof construction. • The design bending moment of two-way restrained slab can be calculated as follows; Moment at short. Sample Design Calculations. 13 and the Elastic Frame Method presented in this chapter. Direct design method, that could have been named the direct analysis method because it determines or prescribes moments for different parts of the slab panel without the need to conduct structural analysis, is explained in the following sections. 25 MPa fy = 300 MPa Analysis and Design of Slabs Two Way. Reinforced Concrete Buildings Series Design Booklet RCB-2. Fig(2- ): Slabs supported at two edges or three. In two way slab, the ratio of longer span (l) to shorter span (b) is less than 2. input cells automatically cross out invalid data 3. For a two way slab the ratio of ly/lx shall be ≤ 2. 25L 2, whichever is less. 75 Kn/m Bending Moment B. Widths to used for design and calculations are : -For the remained slab of column strip: b = 1. The two classifications are one-way slab and two-way slab. The load on the slab is carried by the short span in one direction. 1(a)], in which the structural action is essentially one-way, the loads being carried in direction perpendicular to the supporting beams or walls. The procedure of the design of two-way slabs will have all the six steps mentioned in sec. Fanella, which appeared in the October 2001 edition of Structural Engineer magazine. Computer analysis of two-way slab. usually slabs • When shear reinforcement isrequired e. This types of slabs are mostly used in the floor of. 1_452 the professional development series is a unique oppor- analysis and design of post-tensioned, two-way slabs for example, an 8-inch-thick slab is typical for a. 3 Example 2 - Rectangular Two-Way Slab Designed to AS 3600-2000 Using 500PLUS design Slabs, Slabs,. Determination of Two way slab thickness: Case 1 : interior and edge beams are exist. Reinforcement implementation, static and dynamic analysis For reasons regarding behaviour, safety and economical design, the two-way slab is far more efficient than the equivalent one-way slab. example and guide for modeling a 2D post-tensioned two-way slab frame in the PT mode of the program. 3—Crack control in reinforced two-way action structural slabs and plates. We can distinguish two basic condi-. For those who do not know what are the des ign requirements of a slab. Flat Slab Design [PDF Document]. 14: Bending moment coefficients for two-way restrained slab (Ref. practice, many slabs do not meet these restrictions, for example for round or triangular slabs, slabs with large openings, slabs supported on two or three edges only (as shown in fig. two-way reinforced concrete slab example. Detailing and design of earthquake resistant buildings made of reinforced concrete. Design the slab, following the provisions of the ACK Code. The stages of the example, 1. Assume partitions cannot be damaged by deflections. This document is highly rated by Civil Engineering (CE) students and has been viewed 973 times. The Construction and Design of Concrete Slabs on Grade D. View Design of two-way slabs(D. It can be used by both practicing Engineers and students. Two-way slabs (for m=l l /l s <2) The most common solution for slab systems. In this article, I will discuss how to design One way slab with example. all milld steel reinforcement shall conform to astma-15-62-2t for reinforcing bars 12 ; 280. 54 Russell Road, London Job Ref. A system where a two way slab is continuous with a one way slab or vice versa is called a mixed slab system. Two-Way Slab Design Based on ACI 318-11 using Finite Element Method. Load Paths, One and Two Way Slabs | Structural Concepts and Design - Duration: 10:34. Can be used for larger spans with relatively higher cost and higher deflections One-way joist system suitable span 6 to 9m with LL= 4-6KN/m2. 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. Main features of the spreadsheet 1. ; A Middle strip is a design strip bounded by two column. Title Reinforced Concrete Slab Design Using The Empirical Method Publication No. This appendix presents design examples of the retrofitting techniques for elevation, dry floodproofing, wet. Design Example of a Building IITK-GSDMA-EQ26-V3. Brown' (pdf) About The Author. Depending on the boundary condition and the properties of the slabs, methods of finding bending moment is expressed in the BS 8110 Part 01 as follows. Slabs are usually used in floor and roof construction. The concrete floor slab system shown below is for an intermediate floor to be designed considering partition weight = 20 psf, and unfactored live load = 40 psf. wSD = 20 psf wLL = 80 psf f'c = 4000 psi fy = 60,000 psi span. TN404_slab_shear_050611 SHEAR DESIGN IN FLOOR SLABS1 Bijan O Aalami2 1 - ONE-WAY AND TWO-WAY SHEAR Tests have shown that concrete exhibits greater resistance to shear, when the geometry of its support is square, and of about the same dimensions as slab thickness Fig. Chapters 1. Professor Emeritus. Plan View of Floor System Assume partitions will not be damaged by deflections. Previously known as Method 3 of the 1963 ACI Code. Effective depth of slab in y-direction d y = 250 - 25 - (16/2) = 217 mm. OPTIMUM COST DESIGN OF REINFORCED CONCRETE SLABS USING « 543 continuous slab that depends on the type of slab supports. This problem is. I am third year student persuing B. This spreadsheet is an extremely efficient tool and allows to quickly design two way slabs to aci code. ANALYSIS AND DESIGN OF TWO-WAY SLABS 3. Example Load Distribution Problem 7 The floor system of a library consists of a 6-in thick rein-forced concrete slab resting on four floor steel beams, which in turn are supported by two steel girders. Bending will take place in the two directions in a dish-like form. The design of waffle slabs is the same as that of ribbed slabs, with the difference being that waffle slabs have ribs spanning in both directions, and the coefficients used for analysing the slab is similar to those used for two-way restrained slab. example and guide for modeling a 2D post-tensioned two-way slab frame in the PT mode of the program. 3m at ve moments and as T. The service live load is 100 psf, and 4000 psi concrete is specified for use with steel with a yield stress equal to 60,000 psi. The terms are used interchangeably. The one-way slabs are presented in Section 9. DEFLECTIONS. This paper deals with the problem of optimum design of reinforced concrete (twoway ribbed) waffle slabs using genetic algorithms. Concrete slabs are commonly divided into the following types: • Beamless slabs Beamless slabs are supported only on columns and are applied mostly in large industrial and public buildings. The slab is designed as two way When the ratio of long span to short span is less than 2, then the slab is known as a slab spanning in two directions or two-way slab. Apr 25, 2020 - PPT - Design of Two way Slab Civil Engineering (CE) Notes | EduRev is made by best teachers of Civil Engineering (CE). Waffle slabs can be described as the equivalent of 2-way solid slabs especially when the spans are large, and ribbed system is to be adopted. Unless otherwise noted, all referenced table, figure, and equation numbers are from these books. nice user-friendly interface 2. 9 provides A. m BB 8 l M wl 22 12 A-A 2 1 kN-m, kN. Dutta , IIT Bhubaneswar. In this paper the cost optimization of reinforced concrete two-way slabs under uniformly distributed load with the nonlinear programming approach has been presented and it is a continuation of the. A slab is supported four direction however to taken the ratio b/w length to breadth than the ratio is greater than or equal two ( ly/lx >2) the slab is designed as one way slab. Structural Redesign Two way slab / Drop panels In order to simplify the design of the slab and columns, there was an assumption that shear walls would resist 100% of the The following is an example of a rebar plan in one direction. 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. 5 Kn/m Wall load = 2 Kn/m Live load = 2 Kn/m Total U. The two-way slab on beams, analyzed as separate elements, appeared overdesigned with unnecessarily high safety factors. The stages of the example, 1. The example presented here is for Two-Way Post-Tensioned Design. Type of slab is strongly affected by architectural and construction considerations. The two classifications are one-way slab and two-way slab. Flat Slab Design [PDF Document]. 2 Non-prestressed one-way construction - 9. 85 for f c’ ≤ 4,000 psi, and decreases by 0. Design of Slab (Examples and Tutorials) by Sharifah Maszura Syed Mohsin Example 1: Simply supported One way slab A rectangular reinforced concrete slab is simply-supported on two masonry walls 250 mm thick and 3. The ratio of the total costs was found to be within the range (1. Required reinforcement is displayed in a very. CHAPTER 6—SERVICEABILITY CONSIDERATION. Main features of the spreadsheet 1. Fundamentals of Post-Tensioned Concrete Design for Buildings - Part One covers related topics such as punching shear for two-way slabs and moment transfer at the column. 3m at ve moments and as T. 2—Deflection analysis. A slab is supported four direction however to taken the ratio b/w length to breadth than the ratio is greater than or equal two ( ly/lx >2) the slab is designed as one way slab. European Commission Joint Research Centre Institute for the Protection and Security of the Citizen Contact information Address: Joint Research Centre, Via Enrico Fermi 2749, TP 480, 21027 Ispra (VA), Italy. , and unfactored live load = 100 psf. 1(1) Crack Control of Slabs Part 1: AS 3600 Design 7. The concrete floor slab system shown below is for an intermediate floor to be designed considering partition weight = 20 psf, and unfactored live load = 40 psf. Design example: a simple two-way post-tensioned plate for. Herein the introduction to direct design method. submitted to the faculty of the SCHOOL OF MINES AND M ETALLURGY OF THE UNIVERSITY OF MISSOURI in partial fulfillment of the work required fo r t h e Degree of MASTER OF SCIENCE IN CIVIL E N G I N E E R I N G Rolla, Missouri Approved by. 14: Bending moment coefficients for two-way restrained slab (Ref. RCC Dog-legged Staircase design Excel Sheet. Rectangular Beams and One-way Slabs Page 3 of 9 Design of Rectangular Beams and One-way Slabs (Continued) a = β1 c Where β1 = 0. Slabs can be designed by Direct Design Method known as DDM and another method for design is Coefficient Method which is the easier one. In this article, I will discuss how to design One way slab with example. Per ACI 318 13. Chajjas and verandahs are a practical example of one way slab. Beams, see Lecture 3 • Punching shear requirements e. The execution of the design will be explained with reference to an example. 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 cross-sectional dimensions = 18 in. In this paper the cost optimization of reinforced concrete two-way slabs under uniformly distributed load with the nonlinear programming approach has been presented and it is a continuation of the. 13 and the Elastic Frame Method presented in this chapter. Flat Slab Design [PDF Document]. In addition, already. For the example building, the storey numbers are defined as follows:. CHECKS ON SLABS. The one-way slab is deflected in one way direction. 5 Composite construction Many comments apply to all four sections. The method of Marcus 4. pdf), Text File (. According to the way loads are transferred to supporting beams and columns, slabs are classified into two types; one-way and two-way. Inroduction When the ratio (L/S) is less than 2. Example for finding : for fig. Section Civil & Geotechnical Engineering 1 Calc. The 2012 edition of the Reinforced Concrete Design Manual [SP-17(11)] was developed in accordance with the design provisions of ACI 318-11, and is consistent with the format of SP-17(09). 85 f c’ x b). c) Limiting crack width under increased (design/service) loads or sus-tained loads. 00075tc(12), where tc is the concrete cover. 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. A 2 2Area 2 A' c 2 2 Post-Tensioned Concrete Design Table 1-1 List of Symbols Used in the ACI 318-08 Code cp Area enclosed by the outside perimeter of the section, in A g Gross area of concrete, in A 2 l Total area of longitudinal reinforcement to resist torsion, in A o Area enclosed by the shear flow path, sq-in A oh Area enclosed by the centerline of the outermost closed. PARTITIONING A TWO-WAY SLAB Size of the Model Edge Restraint Springs • •. 75 2 (18 14) ( ) 248. Equilibrium frame method. College of Engineering. Design the two way slab beam supported floor system if it is intended to be used for office building ,assume the partition wall load to be 2 ⁄ I2 Use C25/30 S400 Cover 25 mm Solution. INTRODUCTION In reinforced concrete construction, slabs are used to provide flat, useful surfaces. b) Corrosion of the reinforcement. 2, two-way slabs are designed based on "column strips" and "middle strips". To paraphrase the code: A Column strip is a design strip with a width on each side of a column centerline equal to 0. Net and PTPlus. The program is developed around the robust computational core of two popular programs – PTData. Steel will be more in shorter direction. DEFLECTIONS. , edge beam dimensions = 14 in. Here are the steps for the Design Procedure for One Way Slab in steps. Project: Flat Slab Analysis & Design, In accordance with BS8110:PART 1:1997 Job Ref. Example: Generally all the Cantilever slabs are one Way slab. The behavior of the software has not changed for these examples. The unit weight of reinforced concrete is assumed to be 24 kN/m3. Essential spreadsheet for two way slab design. Direct Design Method alias DDM as well as Coefficient Method are used to design the slabs. Complete Analysis & Design of a Slab on Grade Structure - Analyses uniform thickness finite Slab on Grade with free ends, supported by a vertical subgrade modulus and subjected to a Wall Load, Point Load and Uniform Pressure. There are many methods that are used to analyze two-way slabs and the precision of these methods vary depending. 85 f c’ x b). Reinforced concrete structures II - Two way slab Example Reinforced concrete structures II Page 1 Example 3. m BB 8 l M wl 22 12 A-A 2 1 kN-m, kN. 1(a)], in which the structural action is essentially one-way, the loads being carried in direction perpendicular to the supporting beams or walls. Determine moments at critical sections in each direction, normally the negative moments at supports and positive moment near mid-span. The recommendations derived from these and other studies vary from extremely light to extremely heavy. Reinforced Concrete Buildings Series Design Booklet RCB-2. This PDF file contains a chapter of 23 pages with various aspects of flat slabs including four example of flat slab design. Unless otherwise noted, all referenced table, figure, and equation. Design of Two-Way Floor Slab System 2. The yield line theory 6. Download Free DEMO Updated August 8, 2019 SoilStructure Slab on Grade Software simplifies the calculation of a […]. Tests of flat plate structures indicate that, in most practical cases, the capacity is governed by shear. 0 kN/m2 (excluding slab self-weight) and a variable action of 3. Accordingly, main reinforcement is required in the two directions. 0 k/ft M, kip-ft 38. Design of Slabs Step 1: Assume thickness of slab = 0. Example for finding : for fig. 3—Crack control in reinforced two-way action structural slabs and plates. floodproofing, and construction of a floodwall in a residential setting. 85 f c’ x b). 3 presents two parallel methods for calculating moments in two-way slab systems. Computer analysis of two-way slab. Design of Slab (Examples and Tutorials) by Sharifah Maszura Syed Mohsin Example 2: Continuous one way slab Figure 1 shows a clear area of 12 m x 8. 9m -Beam is designed as rectangular section of b=0. The direct design method is an approximate method used to analyze two way slabs. Modeling the building and obtaining the modal properties (mode shapes and fundamental. ONE WAY SLAB here i solve a probleam based on the one way slab, the diamentions are provided in the probleam 1st determine the aspect ration and with respect to the aspect ratio the type of slab. I am third year student persuing B. One way concrete slab bends or deflects in a direction perpendicular to the supporting. The service live load is 100 psf, and 4000 psi concrete is specified for use with steel with a yield stress equal to 60,000 psi. OPTIMUM COST DESIGN OF REINFORCED CONCRETE SLABS USING « 543 continuous slab that depends on the type of slab supports. Slab thickness of 7 in. txt) or view presentation slides online. In flat-plate floors, slab-column connections are subjected to high shear stresses produced by the transfer of axial loads and bending moments between slab and columns. 6 for the design of one-way slabs except that the bending moments and shear forces are determined by different methods for the two types of slab. The following example illustrates the design methods presented in ACI 318-05 and IBC 2003. The one-way slabs are presented in Section 9. A reinforced concrete slab is built integrally with its supports and consists of two equal spans, each with a clear span of 15 ft. 1(1) Crack Control of Slabs Part 1: AS 3600 Design 7. 2 Example 1: Ultimate Behavior of One-Way Spanning Slab Linear Elastic Analysis Methods such as moment distribution are linear elastic methods. Fig(2- ): Slabs supported at two edges or three. Accordingly, main reinforcement is required in the two directions. This is a part of his project 'Economic design of two way RCC slabs' under Prof S. Two edge supported slab is always one-way. 35 m in all other stories. Two-Way Slabs: Elastic Frame Method 14-1 INTRODUCTION A23. For the Direct Design Method moments are found using a simplified. Have enthusiasm in writing for the professional exam like FE, PE. Two Way Slab Design Spreadsheets to Eurocode 2 14 March 2018 Off By The Engineering Community Two-way spanning slabs For rectangular slabs with standard edge conditions and subject to uniformly distributed loads, normally the bending moments are obtained using tabulated coefficients. Cantilever Slab Design Calculation & Procedure Design of cantilever slab to Eurocode 2 Span of slab 1. The slabs are presented in two groups: one-way slabs and two-way slabs. Beams of width and depth are provided on all column lines; thus the clear-span dimensions for the two-way slab panels are. One-way slabs:. In this paper the cost optimization of reinforced concrete two-way slabs under uniformly distributed load with the nonlinear programming approach has been presented and it is a continuation of the. Two way slab 1. The basic design procedure of a two-way slab system has five steps. m BB 8 l M wl 22 12 A-A 2 1 kN-m, kN. The interior column has a section of 20" x 20" & carries dead & live load of 220 kips & 120 kips respectively. However, because the continuous two-way tendons had to be placed in a draped parabolic profile -near the top of the slab at the column lines, and near the bottom of the slab at midspan - the cables had to be placed in a basket weave pattern. CE 403, Fall 2015 Slab Design Example 1 / 5 (ACI 318‐11 Referenced) Design a one‐way slab for an interior bay of a multi‐story office building using the information specified below. 13 and the Elastic Frame Method presented in this chapter. The following example illustrates the design methods presented in the PCA book "Simplified Design-Reinforced Concrete Buildings of Moderate Size and Height" third edition. This is because it's length to width ratio is (Long/Short) not big enough for loads to travel in the short direction onl. A tendon may contain one or more seven-wire strands. One-way slab design. This problem is. 2 Beams Rectangular beams, inverted L-beams, T-beams 44 3. To paraphrase the code: A Column strip is a design strip with a width on each side of a column centerline equal to 0. A slab is supported four direction however to taken the ratio b/w length to breadth than the ratio is greater than or equal two ( ly/lx >2) the slab is designed as one way slab. Rectangular Beams and One-way Slabs Page 2 of 9 Two Methods: 1. The direct design method. Direct design method is used for the structural analysi s and. CE 403, Fall 2015 Slab Design Example 1 / 5 (ACI 318‐11 Referenced) Design a one‐way slab for an interior bay of a multi‐story office building using the information specified below. 1_452 the professional development series is a unique oppor- analysis and design of post-tensioned, two-way slabs for example, an 8-inch-thick slab is typical for a. In this video deisgn of two way slabs has been covered using IS 456. Two-Way Slab Design Static Equilibrium of Two-Way Slabs Total Moment in both beams Full load was transferred east-west by the planks and then was transferred north-south by the beams; The same is true for a two-way slab or any other floor system where: 2 2 1 kN. In two way slabs, load will be carried in both the directions. system reported herein is small, since the one-way system is small. Main steel is only provided parallel to span. The load on the slab is carried by the short span in one direction. For those who do not know what are the des ign requirements of a slab. There are two types of slab classification based on the direction of bending occurs in these slabs. For complete rebar plans see appendix. Moment CoefficientMethod for two way slabs Direct DesignMethod for two way slabs Analysis and Design of Slabs Department of Civil Engineering, University of Engineering and Technology Peshawar, Pakistan Prof. Slabs may be classified into 2 types depending on ratio of larger side to shorter side, its recommended in IS 456 to design slabs having (ly/lx) ratio greater than 2 as one way slab and slabs having (ly/lx) less than 2 as two way slab. #2 Two 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. The edge column on the left has a section of 16" x 16" and carries dead & live load of 175 kips & 110 kips respectively. Sample Design Calculations. Member/Location. Member Design - Reinforced Concrete Two Way Spanning Slab BS8110 v2015. Essential spreadsheet for two way slab design. The two-way slab S1 is supported by four beams < project: slabs20> 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. 101,234 at University of Duhok. A detailed explanation will be given of the checksto be carried out, the aspects to be considered in the design and the construction procedures and sequences of a post-tensioned slab. 1_452 the professional development series is a unique oppor- analysis and design of post-tensioned, two-way slabs for example, an 8-inch-thick slab is typical for a. Per ACI 318 13. Computer analysis of two-way slab. Tests on three model slabs incorporating minimum reinforcement ratio, minimum depth and maximum bar spacing permitted by the Australian Concrete Structures Code showed satisfactory behaviour at service loads and ultimate loads despite the fact that bending. Direct design method is used for the structural analysi s and. 1—Minimum slab thickness. Part Two is an example-intensive course, with key concepts introduced along the way. In addition to the recommended procedures, other methods are described for the sake of completeness and to compare different methods of design. Before going to this topic, Please read it. 375 kn-m Ultimate Moment Mu = 1. They may be supported on two opposite sides only [Fig. Structural Redesign Two way slab / Drop panels In order to simplify the design of the slab and columns, there was an assumption that shear walls would resist 100% of the The following is an example of a rebar plan in one direction. Depending on the boundary condition and the properties of the slabs, methods of finding bending moment is expressed in the BS 8110 Part 01 as follows. We can distinguish two basic condi-. 61m -For half middle strip: b= 3. Check List for Block / Brick work. The finite element method is commonly used to design the reinforcement in concrete slabs. 3 of ACI 318 allows the use of shear reinforcement for slabs and footings in the form of bars, as in the vertical legs of stirrups. If slab is supported on all four sides and R = (Shorter side / Longer side) < 0. Inroduction When the ratio (L/S) is less than 2. Unless otherwise. College of Engineering. Design of Slab(Two Way) Excel Sheet. Design Of Two Way Slab Example Pdf. 8—Slab shear reinforcement. There are many methods that are used to analyze two-way slabs and the precision of these methods vary depending. For a two way slab the ratio of ly/lx shall be ≤ 2. For the example building, the storey numbers are defined as follows:. m 88BB ll M wl M wl. This spreadsheet performs an analysis and design of two-way spanning reinforced concrete slab. The slab is designed as two way When the ratio of long span to short span is less than 2, then the slab is known as a slab spanning in two directions or two-way slab. The slabs are presented in two groups: one-way slabs and two-way slabs. flat slabs and pad foundations Shear There are three approaches to designing for shear: • When shear reinforcement is notrequired e. Here are the steps for the Design Procedure for One Way Slab in steps. c) Limiting crack width under increased (design/service) loads or sus-tained loads. CE 433, Fall 2006 Slab Design Example 1 / 6 Design a one-way slab for an exterior bay of a multi-story office building using the information specified below. #2 Two 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. The mesh designated 6 x 6 - W2. D = 130 mm d = 105 mm Loads on slab Self weight of slab = 3. pdf), Text File (. Two-Way Slab Design Static Equilibrium of Two-Way Slabs Total Moment in both beams Full load was transferred east-west by the planks and then was transferred north-south by the beams; The same is true for a two-way slab or any other floor system where: 2 2 1 kN. Load Paths, One and Two Way Slabs | Structural Concepts and Design - Duration: 10:34. below), and slabs carrying concentrated loads. D = 130 mm d = 105 mm Loads on slab Self weight of slab = 3. In flat-plate floors, slab-column connections are subjected to high shear stresses produced by the transfer of axial loads and bending moments between slab and columns. 2 Non-prestressed one-way construction - 9. Effective depth of slab in y-direction d y = 250 - 25 - (16/2) = 217 mm. Round slab thickness up to the nearest ¼". However, two-way slabs with bonded tendons are widely used in other parts of the world—notably, Asia, Europe, and Australia. Direct design method, that could have been named the direct analysis method because it determines or prescribes moments for different parts of the slab panel without the need to conduct structural analysis, is explained in the following sections. The yield line theory 6. A slab is supported four direction however to taken the ratio b/w length to breadth than the ratio is greater than or equal two ( ly/lx >2) the slab is designed as one way slab. Design of Slabs Step 1: Assume thickness of slab = 0. The recommendations derived from these and other studies vary from extremely light to extremely heavy. Design of Slab (Examples and Tutorials) by Sharifah Maszura Syed Mohsin Example 2: Continuous one way slab Figure 1 shows a clear area of 12 m x 8. This spreadsheet is an extremely efficient tool and allows to quickly design two way slabs to aci code. Fundamentals of Post-Tensioned Concrete Design for Buildings - Part One covers related topics such as punching shear for two-way slabs and moment transfer at the column. flat slabs and pad foundations Shear There are three approaches to designing for shear: • When shear reinforcement is notrequired e. Main features of the spreadsheet 1. CHECKS ON SLABS. Design of Two-Way Floor Slab System Comparison of One-way and Two-way slab behavior One-way slabs carry load. Concrete slabs are commonly divided into the following types: • Beamless slabs Beamless slabs are supported only on columns and are applied mostly in large industrial and public buildings. Excel Sheet to Design Slab - One Way and Two Way > Share: Rate: Previous Computational Methods for Fluid Dynamics by Ferziger. Design of Slabs Step 1: Assume thickness of slab = 0. Rooms (two way slabs) are continuous with verandah (one way slab). 3 STEP-BY-STEP DESIGN PROCEDURE FOR SLABS Step 1 Analysis Carry out analysis (follow Section 3. Chajjas and verandahs are a practical example of one way slab. face of the column as for flat plates, plates. 101,234 at University of Duhok. According to the way loads are transferred to supporting beams and columns, slabs are classified into two types; one-way and two-way. Example C6. Direct design method is used for the structural analysi s and. Section Civil & Geotechnical Engineering 1 Calc. 3 of ACI 318 allows the use of shear reinforcement for slabs and footings in the form of bars, as in the vertical legs of stirrups. Loads: Framing Dead Load = selfweight Superrimposed Dead Load = 25 psf partitions, M/E, misc. Design a rectangular combined footing to support two columns shown above. BASIC STEPS OF TWO WAY SLAB DESIGN : 1. Application of the yield line theory for more complex situations 8. Slabs are primarily categorized as either one way or two ways. in Civil Engineering in IIT Bhubaneswar. all reinforcement shall be 0. Matthew Stuart, P. Slab thickness: 14 cm. Definition: 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. This PDF file contains a chapter of 23 pages with various aspects of flat slabs including four example of flat slab design. 5m Variable load 4kN/mm2 Slab thickness 175mm Fck 25N/mm2 fyk 500N/mm2 Cover to the reinforcements 25mm Office building Slab loading. 9m -Beam is designed as rectangular section of b=0. In this article, I will discuss how to design One way slab with example. Fig(2- ): Slabs supported at two edges or three. Generally, reservoirs or under ground roads are not constructed every day like other structures. BEHAVIOR OF TWO WAY SLABS A rectangular slab supported on four edge supports, which bends in two orthogonal directions and deflects in the form of dish or a saucer is called two way slabs. 0 kN/m2 (excluding slab self-weight) and a variable action of 3. Chapter 18 - Concrete Slab Structures January 2019 18-8 18. 101,234 at University of Duhok. The design of waffle slabs is the same as that of ribbed slabs, with the difference being that waffle slabs have ribs spanning in both directions, and the coefficients used for analysing the slab is similar to those used for two-way restrained slab. (3) All Slab Design examples have been updated to report the slab design forces rather than the strip forces. 3m at ve moments and as T. Therefore slab is two way. Chajjas and verandahs are an practical example of one way slab. 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. Design example: a simple two-way post-tensioned plate for. 1_452 the professional development series is a unique oppor- analysis and design of post-tensioned, two-way slabs for example, an 8-inch-thick slab is typical for a. Basic Steps in Two-way Slab Design Choose layout and type of slab. 65 C = T ⇒ 0. Check List for Block / Brick work. usually slabs • When shear reinforcement isrequired e. m BB 8 l M wl 22 12 A-A 2 1 kN-m, kN. When a rectangular slab is supported on all the sides and the length-to-breadth ratio is less than two, it is considered to be a two-way slab. I am third year student persuing B. Unformatted text preview: Design of TwoTwo-Way Slabs Flat Plate Flat Slab One-Way One Way Joist Two-Way Joist Slab with Beams Steps in Slab Design • Choose the layout and type of slab: Architectural or construction consideration • Choose the slab thickness: Adequate for deflection/shear • Choose Ch th the method th d ffor d design: i Di Directt Design Method, Elastic frame analysis. 20 TWO-WAY SLABS Service (final) stresses Tension stress as multiple of (f'c)^1/2. This appendix presents design examples of the retrofitting techniques for elevation, dry floodproofing, wet. Slabs having supports on less than four sides can be designed as one-way. Accordingly, main reinforcement is required in the two directions. 1 Two Way Slab Problem Statement: Use the ACI 318 Direct Design Method to design an interior bay of a flat plate slab system of multi bay building. The design shear force can be reduced to account for the loads applied inside the outer perimeter. Design of stair case with central stringer beam. Dutta , IIT Bhubaneswar. 1 and rating requirements as stated in 17. 3 Columns Internal, edge and corner columns 72. Beams, see Lecture 3 • Punching shear requirements e. Bending will take place in the two directions in a dish-like form. Slab is one of the most famous part of a construction project. Thanks in advance.