None way slab design example aci 318 pdf download

Bending will take place in the two directions in a dishlike form. 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. For example, the minimum slab thickness for a twohour fire rating is 4. Two way slab design by direct design method as per aci 31811. 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. Chapter 3 design of rectangular beams and oneway slabs. Download building code requirements for structural. Standard precast concrete box culverts are typically fabricated in 6 foot sections. A complete metric companion to aci 318318r has been developed, 318m318rm.

Technical note 2 parabolic stressstrain curve with the maximum stress at fc and maximum strain at 0. In this post, i will go over the third example in our course that covers the analysis and design of reinforced concrete oneway slabs. The material presented herein is an update of a previous report from aci 352r. If you continue browsing the site, you agree to the use of cookies on this website. Plan view of floor system assume partitions will not be damaged by deflections. This tenth edition of the classic pca publication has been updated to reflect code changes introduced in the latest version of building code requirements for structural concrete, aci 31808, and commentary, aci 318r08. To comply with aci 318, should a designer check punching shear stress with the simultaneous biaxial moments reported by such a model. Deflection of two way slab could be calculated by using available methods to make sure that the deflection will not. Using the minimum depth for nonprestressed beams in table 9.

One way slab is normally designed for gravity load only. This method was the prevalent methodology up until the 1971 edition of the aci code, and the evaluation is accomplished using service loads. One way slab aci code concrete download the design spread sheet here. The program covers wide range of twoway slab systems and can be used for more complex slab layouts.

The corner beams are 400 mm wide and intermediate beams are 350 mm wide. This table gives guidance on the minimum thickness of nonprestressed beams or oneway slabs. Twoway slab design based on aci 31811 using finite. Equivalent tensile stress design appendix 5examples using shrinkagecompensating concrete, p. The cross section of a continuous oneway slab is shown in the figure below. Minimum thickness of two way slab as per aci 31811 for.

Aci 31802 was adopted as a standard of the american concrete institute november 1, 2001 to supersede aci 31899 in accordance with the institutes standardization procedure. The ddm can be utilized for twoway slab design only if the criteria in aci 318. Distinction of twosystems from oneway systems is given by aci 31814 r8. Some of the most important changes are found in chapter 18, earthquake resistant structures, and chapter 19, concrete. One way slab design spreadsheet according to aci civil. With the advent and popularity of finite element analysis software, engineers can create sophisticated models of twoway slabs supported by columns. Structural design highlights of aci 31819 part 2 of 2. Aci design factors for calculating shear and moment in slab limitation. Generally castin place floor slabs acting as thin deep beams to. Continuous one way slab design and analysis for reinforced. User is given the option to override the code value. Download building code requirements for structural concrete aci 31811 and commentary pdf for free. The maximum allowable hypothetical tensile stress for oneway slabs and beams depends on the selection of design in one of the three classes of uncracked. Organizational changes organization of aci 31811 the organization of aci 31811 followed a framework that was started with aci 31871.

Design of reinforced concrete as per aci 318 11 14,794 views. Load transfer in a oneway slab, b twoway slab nilson fig. The goal of this reinforced concrete design example is to design a simply supported reinforced concrete oneway slab subjected to. Analysis and design of slabs two way civil engineers pk. Twoway slab design based on aci 31811 using finite element method 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 twoway slab. Aci 31814 building code requirements for structural concrete. Twoway slab analysis and design aci 318 states that a slab system shall be designed by any procedure satisfying equilibrium and geometric compatibility, provided that strength and serviceability criteria are satisfied. 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. All design examples in this text have been revised to reflect the new notation and terminology, load and strength reduction factors, and the unified design provisions for. Aci documents are available in print, by download, on. American concrete institute presents a pdf ebook on building code requirements for structural concrete aci 31811 and commentary. Design examples are provided to show the basis and use. Placement of reinforcement in the slab section designed in flexure. 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.

Though nearly identical in format with the current aci 31805, the aci 349 version of appendix d has some differences that will be demonstrated in the examples. The other is known as the strength design method or ultimate strength design usd, and is the predominant design method used in the design of reinforced concrete structures. Ce 403, fall 20 oneway slab design 3 4 aci 31811 referenced pp 2 4 rating. Oneway and twoway slabs oneway slabs transfer the imposed. Designing a continuous one way reinforced concrete slab. Minimum thickness for two way slab construction designed as per methods provided by aci 31811 code namely, direct design method and equivalent frame method.

Aci 31811 code provides two methods for two way slab design one of which is direct design method. The following example illustrates the example building. Aci 31811 was adopted as a standard of the american concrete institute may 24, 2011, to supersede aci 31808 in accordance with the institutes standardization procedure and was published august 2011. Designing a simply supported reinforced concrete one way. The minimum thickness of slab is specified by aci 31811, section 9. Two way slab design as per method 3 minorchord2000 structural 24 oct 07 18. Design manual concrete american concrete institute. Design of reinforced concrete structures ii twoway slabs. These conclusions are further formatted to satisfy the aci code language, since they are to be implemented upon approval by the presiding committee, as a modificationaddition to the existing deflection control provisions of aci 318 section 9. Design an eight span floor slab considering 1 m wide strip. Twoway flat plate concrete slab floor analysis and design aci 31814. The concrete strength is 25 mpa and the reinforcement strength is 400 mpa. Determine beam shear strength of concrete by method of.

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. Modulus of elasticity of concrete is automatically calculated and displayed by the program using fc, wc, and the following relationship 3 of the code. The first step is to find the total slab thickness, h, with the aid of table 9. Rectangular beams and oneway slabs page 5 of 9 maximum permissible steel ratio, max an overreinforced beam will fail in a brittle manner while an underreinforced beam will. Reinforced concrete continuous beam analysis and design aci 31814. Two way slab design as per method 3 aci concrete code. Aci documents are available in print, by download, on cdrom. The tensile strength of concrete is neglected in flexural strength calculations aci sec. One way slab design spreadsheet according to aci become a vip member to see this content. Founded in 1904 and headquartered in farmington hills, michigan, usa, the american concrete institute is a leading authority and resource worldwide for the development, dissemination, and adoption of its consensusbased standards, technical resources, educational programs, and proven expertise for individuals and organizations involved in concrete. 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. Significant changes from the 2011 to the 2014 edition of.

Aci 318 provides two alternative methods for designing twoway slabs for concrete, the equivalent frame method. Oneway and twoway slabs university of asia pacific. Previous article minimum thickness of solid slab according to aci. Twoway slabs have two way bending unlike oneway slab. 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 twoway slab. Aci 31808 code requirements for design of concrete floor systems. Aci 31814 does contain a number of significant technical changes. Accordingly, main reinforcement is required in the two directions. There is a minimum of three continuous spans in each direction aci 318.

Aci 31811 defines stretch length as the length of anchor extending beyond the concrete, subject to tensile load. Shear wall design aci 31814 the program provides detailed output data for simplified pier section design, uniform pier section, and section designer pier section designcheck designcheck chapter 4. In twoway slabs shorter direction strip carry greater %age of load. Generally castinplace floor slabs acting as thin deep beams to. The output of the program for the slab in the example is shown in the following pages. The aim of this reinforced concrete design example is to design a continuous reinforced concrete oneway slab subjected to dead and live loads per aci code 31811. Type of slab is strongly affected by architectural and construction considerations. The format for each example follows the format of the aci design handbook, sp17, and provides a reference back to the code paragraph for each calculationprocedure. Finally, since shear reinforcement is not used in oneway slabs, the concrete must be able to resist the maximum shear force. One way slab design and analysis for reinforced concrete. Design of reinforced concrete structures ii twoway slabs 1 1. Use i wsd, ii usd to design the twoway slab shown below, carrying floor finish 30 psf, random wall 50 psf and live load 60 psf given.