EFFECT OF RC CONFINING ELEMENTS ON STIFFNESS OF ADOBE MASONRY STRUCTURE

Abstract

Adobe construction in rural areas is quite common due to locally available material. In developing
countries, the adobe construction is increasing due to its thermal and acoustic properties. Different types of structures
have been built in ancient times from earth. From heritage point of view, the adobe construction is of great importance
but we cannot ignore its disadvantages due to its mechanical properties such as lower strength of masonry units, lack of
resistance to wind and rain. Adobe masonry has shown poor performance in past earthquake. The reason behind that
was lower shear and tensile strength. Due to its massive weight of wall and excessive weight from roof, it attracts large
forces during ground shaking which it cannot resist and fail abruptly. People are unaware and they are regularly
constructing these structures in their areas where seismic hazard is high. To improve the seismic capacity of these adobe
structures different schemes had been developed, but in this research we have used Reinforced Concrete (RC)
components as confining elements to improve its performance during earthquake. Two models have been tested on shake
table, one with vertical columns and beams and the other model with only beams at different level along the height of
wall. Comparison of Lateral strength of structure in term of base shear coefficient and stiffness has been made. Addition
of vertical columns has increased structural stiffness and structural strength 3.50 times and 5 times respectively that of
model with beams only.