Ingeniería e Investigación
Print version ISSN 0120-5609
RESTREPO MEJIA, Juan Carlos and TAKEUCHI TAM, Caori Patricia. Studying boundary elements behaviour using masonry walls built with high-resistance bricks. Ing. Investig. [online]. 2006, vol.26, n.2, pp. 10-19. ISSN 0120-5609.
This research was aimed at studying the behaviour of masonry walls built with and without boundary elements at both ends when subjected to monotonic and cyclic lateral loads. The walls were designed to have the greatest resistance, following NSR-98 recommendations (normas Colombianas de diseño y construcción sismo resistente), except for shear reinforcement. XTRACT software was used for finding axial load cf bending moment and curvature cf bending moment curves. One monotonic test and two cyclic tests were performed for each type of wall. Experimental results from the walls lateral load cf displacement curves were used for determining their ability to dissipate energy on an inelastic range (R force-reduction factor for seismic loads) and displacement and curvature malleability. It was found that walls built without boundary elements suffered shear failure with cracks in a stepped configuration along the bricks edge. The type of failure for walls built with boundary elements was shear failure in the central panel with cracks in a stepped configuration, in addition to compression failure at the edge of the boundary elements with vertical cracks on the lower part of the wall and at the contact between the wall and the boundary element. Comparison with two other studies carried out at the Universidad Nacional showed similar cyclic behaviour, regardless of the clay bricks strength. The R values obtained for both types of walls were lower than the recommended values given by NSR-98. It was determined that walls having boundary element have greater displacement malleability than walls without boundary elements.
Keywords : boundary element; structural masonry; cyclic test; monotonic test; maleability; energy dissipation ability.