Abstract:
RCC columns are common in low or medium rise masonry buildings and bridges. These old masonry buildings, bridges and other structures have outlived their durability due to continues environmental effects or these are being used for purposes other than those for which these were originally designed. This has placed higher loads on slabs, columns, beams and foundations. Moreover the existence of many old masonry buildings in the earthquake prone regions is also a serious hazard to life and property. Due to economic constraints, the old distressed structures are being used with complete disregard to loss of human lives.
There are several types of masonry structural elements within a building, among which column is the most vulnerable to environmental effects and earthquake damages. Columns are primarily designed to carry the vertical loads, however, in case of any seismic activity they also experience horizontal loads from the ground movements. Column failure can lead to collapse of structure and result in loss of life and property.
Ferrocement is a highly versatile form of reinforced concrete, constructed of hydraulic cement mortar and reinforced with closely spaced layers of continuous and relatively small diameter wire meshes. Because of the excellent mechanical properties, ferrocement has a wide range of applications in civil works. Among the potential fields, the most recommended is, the field of rehabilitation and repair of old distressed structures. Encasement by ferrocement can be used to increase the load carrying capacity, as well as moment resistance of RCC columns.
In Pakistan most of the old structures including bridges and old cultural heritage are made of brick masonry columns, which have lost their durability and do not fulfill the present ACI safety provisions. This research work investigates the possibility of using ferrocement as a retrofit/ strengthening material for such columns. The potential encouraging results from this research work can lead to a viable and economical solution for these old distressed masonry structures by enhancing their useful life and increasing the safety.
