Category: Masonry Structural design

This book was developed from a set of masonry course notes used for many years in a semester-long, undergraduate and graduate course in masonry engineering at The University of Texas at Austin. It covers the design of masonry structures using the 2009 International Building Code, the 2008 Masonry Standards Joint Committee Code and Specification, and other documents referenced by those standards. The book is intended for an undergraduate or a graduate course in masonry as part of a civil engineering or architectural engineering curriculum. It can also be used for self-study and continuing education by practicing engineers. It emphasizes the strength design of masonry, and also includes allowable-stress design.

Category: Masonry Structural design Required Details for Reinforced Bearing Walls and Shear Walls

Bearing walls that resist out-of-plane lateral loads, and shear walls, must be designed to transfer lateral loads to the floors above and below. Examples of such connections are shown in Figs. 6.30 through 6.34. These connections would have to be strengthened for regions subject to strong earthquakes or strong winds. Section 1604.8.2 of the 2009 IBC has additional requirements for

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Category: Masonry Structural design Additional Comments of the Design of Reinforced Shear Walls

Reinforced masonry shear walls, like unreinforced ones, are relatively easy to design by either strength or allowable-stress approaches. Although shear capacities per unit area is small, the available area is large. With either strength or allowable-stress approaches, it is rarely necessary to use shear reinforcement. In this sense, the best shear design strategy for shear walls is like that for

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Category: Masonry Structural design Minimum and Maximum Reinforcement Ratios for Flexural Design of Masonry Shear Walls by the Strength Approach

Minimum Flexural Reinforcement by 2008 MSJC Code The 2008 MSJC Code has no global requirements for minimum flexural reinforcement for shear walls. Maximum Flexural Reinforcement by 2008 MSJC Code The 2008 MSJC Code has a maximum reinforcement requirement (Sec. 3.3.3.5) that is intended to ensure ductile behavior over a range of axial loads. As compressive axial load increases, the maximum

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Category: Masonry Structural design Example of Strength Design of Reinforced Clay Masonry Shear Wall

Consider the masonry shear wall shown in Fig. 6.26. Design the wall. Unfactored in-plane lateral loads at each floor level are due to earthquake, and are shown in Fig. 6.27, along with the corresponding shear and moment diagrams. Assume an 8-in. nominal clay masonry wall, grouted solid, with Type S PCL mortar. The total plan length of the wall is

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Category: Masonry Structural design Strength Design of Reinforced Shear Walls

Introduction to Strength Design of Reinforced Shear Walls In this section, we shall study the behavior and design of reinforced masonry shear walls. The discussion follows the same approach used previously for unreinforced masonry shear walls. Design Steps for Strength Design of Reinforced Shear Walls Reinforced masonry shear walls must be designed for the effects of: 1. Gravity loads from

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Category: Masonry Structural design Minimum and Maximum Reinforcement Ratios for Out-of-Plane Flexural Design of Masonry Walls by the Strength Approach

The strength design provisions of the 2008 MSJC Code include requirements for minimum and maximum flexural reinforcement. In this section, the implications of those requirements for the out-of-plane flexural design of masonry walls are addressed. Minimum Flexural Reinforcement by 2008 MSJC Code The 2008 MSJC Code has no requirements for minimum flexural reinforcement for out-of-plane design of masonry walls. Maximum

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Category: Masonry Structural design Example of Strength Design of Masonry Walls Loaded Out-of-Plane

Once we have developed the moment-axial force interaction diagram by the strength approach, the actual design simply consists of verifying that the combination of factored design axial force and moment lies within the diagram of nominal axial and flexural capacity, reduced by strengthreduction factors. Consider the bearing wall designed previously as unreinforced, shown in Fig. 6.19. It has an eccentric

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Category: Masonry Structural design Example of Interaction Diagram by the Strength Approach (Spreadsheet Calculation)

Construct the moment-axial force interaction diagram by the strength approach for a nominal 8-in. CMU wall, fully grouted, with fm′ = 1500 lb/in.2 and reinforcement consisting of #5 bars at 48 in., placed in the center of the wall. The effective width of the wall is 6t, or 48 in. The spreadsheet and corresponding interaction diagram are shown in Fig.

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Category: Masonry Structural design Strength Interaction Diagrams by Spreadsheet

To calculate strength interaction diagrams using a spreadsheet, we first calculate the position of the neutral axis corresponding to the balance point (Fig. 6.15). For values of c less than that balanced value, the steel will yield before the masonry reaches its maximum useful strain. Combinations of axial force and moment corresponding to nominal capacity can then be calculated, as

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Category: Masonry Structural design Example of Moment-Axial Force Interaction Diagram by the Strength Approach (Hand Calculation)

Construct the moment-axial force interaction diagram by the strength approach for a nominal 8-in. CMU wall, fully grouted, with fm′ = 1500 lb/in.2 and reinforcement consisting of #5 bars at 48 in., placed in the center of the wall. Compute the interaction diagram per foot of wall length. For the case of a wall with reinforcement at mid-depth, the reference

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