Abstract Database :: SEISMIC EVALUATION AND RETROFITTING OF A WEAK 8 STORIED RC BUILDING IN BANGLADESH AND EFFECT OF MASONRY INFILL WALL

Many of the existing buildings in Bangladesh built before publishing the first building design code in 1993. Most of the buildings found to be non-engineered and also very low seismic capacity. In addition, reinforced concrete buildings with masonry infill is very common practice in Bangladesh. However, still the masonry infill is considered as nonstructural member having no contribution in seismic evaluation manual which was published based on JBDPA standard. The individual study aims at evaluation of RC framed building for both bare frame and considering masonry infill effect.

Three methods were utilized for seismic evaluation of building namely simplified evaluation, advanced simplified evaluation and second level screening. Simplified evaluation and second level screening were conducted for both bare frame and incorporating masonry infill effect. The reduction factor for the masonry infill due to opening proposed by different researchers were compared for second level screening. To numerate the strength index and ductility index of masonry infill some papers were reviewed to incorporate the effect with masonry infill in seismic evaluation.

It was found from the evaluation with simplified evaluation and second level screening the infill wall increased the seismic index significantly. The requirement for retrofitting was reduced when considering the masonry infill wall contribution. The three retrofitting techniques were taken into account namely RC wing wall installation, steel framed bracing and ferrocement. The unconventional retrofitting technique ferrocement was found to be the most cost effective among the three retrofitting techniques.

Keywords: Masonry infill, strength index, ductility index, seismic index, retrofit