Retrofitting Solutions for Existing Open Ground Storey RC Buildings

In the last few decades with the increase in population and decrease in usable land, there has been an enormous rise in the construction of residential buildings with open ground storey (OGS) to facilitate vehicle parking. Such OGS are created by removing the infill walls in the first storey. However, during the past earthquakes many of such OGS buildings have suffered severe damage and sometimes complete collapse of the structure. This is because OGS buildings, in general, exhibit soft story irregularity. Although the design codes have recommended provisions to enhance the seismic capacity of the OGS buildings, such provisions are barely implemented during construction. In order to avoid casualties and economic losses, it is necessary to retrofit the existing OGS structures. In this work, an attempt is made to strengthen the OGS buildings using masonry infill walls and braces as the retrofitting solutions. The models are developed in Seismostruct and analysed using suitable analytical methods. The behaviour of OGS buildings with masonry and braces at selected locations is evaluated. Retrofitting solutions that provide enhanced seismic performance and maximum parking space are proposed.