Experimental cyclic behavior of reinforced concrete wall houses loaded in their weak direction

This research presents a study of the lateral capacity of the reinforced concrete houses constructed in Puerto Rico. These houses are built with a reinforced concrete roof slab and three reinforced concrete walls oriented in the same direction. The lateral loads applied in the direction perpendicular to the reinforced concrete walls are resisted by the frame action of the walls and roof acting in the weak direction of the walls and by partition walls, which are typically built of concrete blocks.; The experimental part of the study was focused in testing six full scale one story specimens comprised each of three reinforced concrete walls monolithic with the roof slab subjected to cyclic loading in the weak direction of the assembly. Five of the specimens contained concrete block walls in one of the bays. The concrete block walls were constructed under different configurations of the steel reinforcement and openings. The results demonstrated that the lateral resistances of the specimens were governed by different failure modes; among of them are: plastic hinges at the R/C wall ends, punching shear failure of R/C walls and roof slab, masonry corner crushing, toe crushing and shear failure of the piers. The lateral capacity and the energy dissipation of the specimens increased significantly when partition wall was included inside the frame.; The analytical part of the research included the development and the validation of simple analytical models of the full scale specimens. Once validated, the analytical models of each component of the house were used to construct a full house computer model. The full house computer model was used to perform seismic response predictions of the typical residential house subjected to a four earthquake motions in its weak direction. The results showed that this structure can withstand the seismic demand imposed by Uniform Building Code 1997 for Seismic Zone 3 and Soil Type Sd in the elastic regimen. Severe damage is expected when the earthquake records where scaled to peak ground acceleration (PGA) of 1.0g; 2.77 times the PGA established by UBC-1997.