Seismic Design of Confined Masonry Walls
J. Bariola and C. Delgado
Appears on pages(s):
bending; confined concrete; deformation; masonry walls; models; shear strength; standards; stiffness; strength; Design
The objective of this paper is to present models for the design of confined masonry structures based on the available experimental data. In particular, this study deals with in-plane response of masonry walls subjected to lateral forces, with emphasis on aspects of initial stiffness, strength, and deformation capacity. The experimental information used in this work comprises tests performed at the Structures Laboratory of the Catholic University of Peru. Results indicate that stiffness can be calculated considering a wall cross section inertia using the transformed cross section concept with the appropriate moduli of elasticity for concrete and masonry. Bending strength can be estimated reasonably well, assuming for the cross section (1) a rectangular compressive stress distribution, (2) zero strength under tension, and (3) a linear strain distribution. Unit shear strength could be safely calculated as 0.5 f'm, where f'm is the characteristic compressive strength of masonry. It is observed that confined masonry can develop drift values larger than 0.5 percent of wall height, which is comparable to that of reinforced masonry. Deformation capacity is observed to increase for increasing wall horizontal reinforcement ratio and column horizontal and vertical reinforcement and to be reduced with increasing axial load.