Investigation of Confined Masonry Using Non-standard Quality of Concrete and Reinforcement

Abstract

Masonry structure is a common type of residential house in several regions. A significant number of guidelines were issued to enhance the resistance of such house against earthquakes. The International Association for Earthquake Engineering (IAEE) published a Guideline for Non-Engineered Earthquake Resistant Construction. Referring to this guideline by adjusting to local conditions, the Indonesian Ministry of Public Works has developed a guideline on how to build dwellings, especially for houses made of bricks masonry, confined by reinforced concrete (RC) frames. However, despite the availability of the guidelines, field observation on masonry construction practices shows that the qualities of concrete are still inadequate, and the steel reinforcement configurations were different compared to those on the guidelines. An experimental study was conducted to obtain the effect of concrete quality disparity and reinforcement configuration of the RC frame on the brick masonry wall performance. The wall specimens made of brick masonry were loaded cyclically, from the top of the wall in the plane direction up till failure. The test results suggest that the nonstandard quality of concrete contributes no significant effect on the stiffness, strength, deformation ability, and ductility of the walls. Early damage of all specimens occurs in the bottom end of the RC column before reaching the load capacity. Strong anchorage is needed by continuing the longitudinal column reinforcement to the foundation of the wall.