SEISMIC PERFORMANCE ASSESSMENT OF CONFINED ADOBE MASONRY STRUCTURES

This paper presents shake-table tests which were performed on two 1:3 reduce-scaled adobe masonry models confined with vertical and horizontal bands. The model AM1 consisted of bands (tie beam) at sill, lintel and eave levels, and lightly reinforced concrete (RC) columns at the corners. The model AM2 was similar to AM1 except that RC columns at the corners were not provided in this model. The models were subjected to sinusoidal base motions for studying their seismic performance. The lateral force-deformation capacity curves for both the models were developed and were bi-linearized to compute the response parameters including stiffness, strength, ductility and response modification factor (R). Seismic performance levels of both the models were defined and their seismic performance assessment was carried out to evaluate their suitability in different seismic zones. The use of vertical columns in the AM1 model considerably increased its lateral strength as compared to the AM2 model. Although R factor of 2.0 has been recommended for both the models, seismic performance of the AM1 model was found better in all seismic zones due to high lateral strength of this model.