Design and Analysis of Concrete Masonry and Precast ...

1 Lintel Design ManualDesign and Analysis of Concrete Masonryand Precast Concrete LintelsLintel Design ManualDesign and Analysis of Concrete Masonryand Precast LintelsNATIONAL Concrete Masonry ASSOCIATIONThe National Concrete Masonry Association (NCMA) is a not-for-profit organization whose mission is tosupport and advance the common interests of its members in the manufacture, marketing, research, and appli-cation of Concrete Masonry products. The Association is an industry leader in providing technical assistanceand education, marketing, research and development, and product and system innovation to its members andto the 2004 National Concrete Masonry AssociationiDISCLAIMERNCMA promotes the use of Concrete Masonry through the development and dissemination of technical infor-mation. This manual was compiled to assist the designer, builder, or owner in the preparation of constructingwith Concrete Masonry .

2 The discussion, Design tables, and Design philosophies are intended to assist architectsand engineers in the Design of Concrete Masonry and Precast Concrete lintels and to acquaint builders andcontractors with recommended construction methods and material presented does not cover all possible situations but is intended to represent some of the morewidely used Concrete Masonry Design and construction details and other pertinent information. Factors such asconstruction practices and building code requirements can vary significantly, even in the same locality. For thisreason, the information contained in the handbook is necessarily of a general nature when illustrating typicaldesign conditions, assumptions, and procedures. The actual Design of lintels, preparation of working draw-ings, and similar services are best accomplished by a qualified architect or engineer familiar with local condi-tions and code has been taken to ensure that the information included in this manual is as accurate as possible.

3 However,NCMA does not assume responsibility for errors or omissions resulting from the use of this manual or in its usewhen preparing plans or 2004 National Concrete Masonry AssociationNCMA Publication TR 91B, Second Printing 2012 ISBN 1-881384-19-7 NCMA Engineering and Research StaffRobert D. Thomas - Vice President of EngineeringJeffrey H. Greenwald, - Vice President of Research and DevelopmentR. Lance Carter, - Manager of Engineered Landscape ProductsDennis W. Graber - Director of Technical PublicationsJason J. Thompson - Structural EngineerPublished byNational Concrete Masonry Association13750 Sunrise Valley DriveHerndon, VA in the United States of AmericaiiTABLE OF CONTENTS PageList of of of 1 - 1-1 SECTION 2 - 2-1 SECTION 3 - Design of Arching 3-6 SECTION 4 - LINTEL Stress Design of Concrete Masonry Masonry Concrete 4-3 SECTION 5 - Design 5-1 SECTION 6 - LINTEL Design 6-1 SECTION 7 - 7-1 APPENDIX A - BEAM DIAGRAMS AND A-1 APPENDIX B - METRIC B-1 Lintel Design Manualiiiiva=depth of an equivalent compression zone at nominal strength, cross-sectional area of Masonry , cross-sectional area of steel, area of shear reinforcement, width of section, distance of cell where reinforcement is placed.

4 From extreme compression fiber to centroid of tension reinforcement, of reinforcing bar, distance between horizontal bars, depth of Masonry in direction of shear considered, of elasticity of Concrete , of elasticity of Masonry , of elasticity of steel, psi. fc=specified compressive of Concrete , psi. fm=specified compressive strength of Masonry , compressive stress of Masonry due to flexure only, tensile stress in reinforcing steel, shear stress in Masonry , shear stress due to Design load , yield strength of steel for reinforcement, to apex of triangle for arching action, of Masonry above lintel, height, of distance between centroid of flexural compressive forces and centroid of tensile forces todepth, of the distance between compression face and neutral axis to the effective depth, span length, live moment of Masonry , moment strength of a cross-section before application of strength reduction factor, moment of lintel, moment of reinforcing steel, of modulus of elasticity of reinforcement to modulus of elasticity of load .

5 =pounds per cubic =pounds per square load or seismic response modification factor as of reinforcement, spacing, OF NOTATIONSL intel Design Manualvt=thickness, shear strength provided by Concrete , strength provided by masory Masonry , shear strength of a cross-section before application of strength reduction factor, shear of lintel, strength provided by shear reinforcement, per unit length, lb/ft. =tension reinforcement yield strain factor. y=yield strain of reinforcement. mu=maximum usable compressive strain of Masonry . =strength reduction factor. =reinforcement OF NOTATIONS continuedFigureTitlePage2-1 Lintel and Bond Beam 2-23-1 Typical load 3-13-2 Arching 3-23-3 Lintel Design 3-33-4 Distribution of Concentrated load Over Running 3-43-5 Light Roof/Floor 3-53-6 Heavy Roof/Floor 3-63-7 Distribution of Concentrated load Over Stack 3-74-1 Effective Span 4-34-2 Detailing Limitations of Reinforcing 4-44-3 Construction Details.

6 Simple 4-74-4 Concrete Masonry Lintel 4-84-5 Precast Concrete Lintel 4-85-1 Masonry Wall 5-15-2 Interior 5-45-3 Residential 5-65-4 Warehouse 5-85-5 Lintel 5-9A-1 Simple Beam - Concentrated load at A-1A-2 Simple Beam - Concentrated load at Any A-1A-3 Simple Beam - Uniformly Distributed A-2A-4 Simple Beam - Uniform load Partially Distributed at One A-2A-5 Simple Beam - Triangular A-3A-6 Beam Fixed at Both Ends - Concentrated load at A-3A-7 Beam Fixed at Both Ends - Concentrated load at Any A-4A-8 Beam Fixed at Both Ends - Uniform A-4A-9 Beam Fixed at Both Ends - Uniform load Partially Distributed at One A-5A-10 Beam Fixed at Both Ends - Triangular A-5 LIST OF FIGURESviLintel Design ManualviiLIST OF TABLES viii Material Weights for 6 Inch Single Wythe Weights for 8 Inch Single Wythe Weights for 10 Inch Single Wythe Weights for 12 Inch Single Wythe Shear and Moment for Nominal 6 x 8 in.

7 Concrete Masonry Shear and Moment for Nominal 6 x 16 in. Concrete Masonry Shear and Moment for Nominal 6 x 24 in. Concrete Masonry Shear and Moment for Nominal 8 x 8 in. Concrete Masonry Shear and Moment for Nominal 8 x 16 in. Concrete Masonry Shear and Moment for Nominal 8 x 24 in. Concrete Masonry Shear and Moment for Nominal 10 x 8 in. Concrete Masonry Shear and Moment for Nominal 10 x 16 in. Concrete Masonry Shear and Moment for Nominal 10 x 24 in. Concrete Masonry Shear and Moment for Nominal 12 x 8 in. Concrete Masonry Allowable Shear and Moment for Nominal 12 x 16 in. Concrete Masonry Shear and Moment for Nominal 12 x 24 in. Concrete Masonry Shear and Moment for Nominal 6 x 8 in. Concrete Masonry Shear and Moment for Nominal 6 x 16 in. Concrete Masonry Shear and Moment for Nominal 6 x 24 in.

8 Concrete Masonry Shear and Moment for Nominal 8 x 8 in. Concrete Masonry Shear and Moment for Nominal 8 x 16 in. Concrete Masonry Shear and Moment for Nominal 8 x 24 in. Concrete Masonry Shear and Moment for Nominal 10 x 8 in. Concrete Masonry Shear and Moment for Nominal 10 x 16 in. Concrete Masonry Shear and Moment for Nominal 10 x 24 in. Concrete Masonry Shear and Moment for Nominal 12 x 8 in. Concrete Masonry Shear and Moment for Nominal 12 x 16 in. Concrete Masonry Shear and Moment for Nominal 12 x 24 in. Concrete Masonry Shear and Moment Capacity for Nominal 6 x 8 in. Concrete Masonry Shear and Moment Capacity for Nominal 6 x 16 in. Concrete Masonry Shear and Moment Capacity for Nominal 6 x 24 in. Concrete Masonry Design Manual Shear and Moment Capacity for Nominal 8 x 8 in.

9 Concrete Masonry Shear and Moment Capacity for Nominal 8 x 16 in. Concrete Masonry Shear and Moment Capacity for Nominal 8 x 24 in. Concrete Masonry Shear and Moment Capacity for Nominal 10 x 8 in. Concrete Masonry Shear and Moment Capacity for Nominal 10 x 16 in. Concrete Masonry Shear and Moment Capacity for Nominal 10 x 24 in. Concrete Masonry Shear and Moment Capacity for Nominal 12 x 8 in. Concrete Masonry Shear and Moment Capacity for Nominal 12 x 16 in. Concrete Masonry Shear and Moment Capacity for Nominal 12 x 24 in. Concrete Masonry Shear and Moment Capacity for Nominal 6 x 8 in. Concrete Masonry Shear and Moment Capacity for Nominal 6 x 16 in. Concrete Masonry Shear and Moment Capacity for Nominal 6 x 24 in. Concrete Masonry Shear and Moment Capacity for Nominal 8 x 8 in. Concrete Masonry Shear and Moment Capacity for Nominal 8 x 16 in.

10 Concrete Masonry Shear and Moment Capacity for Nominal 8 x 24 in. Concrete Masonry Shear and Moment Capacity for Nominal 10 x 8 in. Concrete Masonry Shear and Moment Capacity for Nominal 10 x 16 in. Concrete Masonry Shear and Moment Capacity for Nominal 10 x 24 in. Concrete Masonry Shear and Moment Capacity for Nominal 12 x 8 in. Concrete Masonry Shear and Moment Capacity for Nominal 12 x 16 in. Concrete Masonry Shear and Moment Capacity for Nominal 12 x 24 in. Concrete Masonry Shear and Moment Capacity for Nominal 4 x 8 in. Reinforced Concrete Shear and Moment Capacity for Nominal 6 x 8 in. Reinforced Concrete Shear and Moment Capacity for Nominal 8 x 8 in. Reinforced Concrete Shear and Moment Capacity for Nominal 16 x 8 in. Reinforced Concrete OF TABLES continuedINTRODUCTIONS ection 11-1 Openings in Concrete Masonry walls aretypically spanned by horizontal structural membersknown as lintels.