Problem Assignment - Perforated Masonry Shear Walls
A perforated shear wall is subjected to horizontal wind loads at the first and second levels as shown in Figure 1. The wind loads may reverse from the direction shown in the figure. In addition, each base-story pier carries an unfactored dead load of 5.0 kips and an un-factored live load of 3.0 kips.
The wall is constructed using a single wythe of 8" concrete masonry units that are laid in running bond and are fully grouted. Prism compressive strength is measured to be equal to 2000 psi. Type S mortar with masonry cement is used. The wall is constructed in a region where the 2016 MSJC code is applicable.
For each of the two piers, determine demand-to-capacity (D/C) ratios for shear and flexure for the following cases.
(a) unreinforced masonry per Allowable Stress Design (D/C = applied stress/allowable stress)
(b) reinforced masonry per Strength Design (D/C = applied forces/force capacities)
For Part (b), consider that the piers are reinforced with two #5 Grade 60 reinforcing bars in the vertical direction as shown in the wall cross sectional views, and #4 horizontal bars at 32" spacing.
