During rock excavation by blasting, part of explosive energy is exhibited in the form of elastic waves. These waves travelling in all directions, give rise to ground vibrations, which in excess may cause damage to the nearby structures and rock strata. This phenomenon is of more concern for construction projects where parallel excavation and concreting activity is executed. Gulpur hydropower project is a 102MW project located on Poonch River in Kotli Azad and Jammu Kashmir, Pakistan. The constraint of time enforced the construction team to carry out blasting and concreting activity side by side. To ensure that both activities were carried out mutually in a safe and progressive manner, a site specific attenuation curve was established. A set of almost 50 excavation blasts were recorded with their explosive charge and induced vibrations at varying scaled distances. This data was developed into a relationship between Peak particle velocity and Scaled distance. The capacity of any concrete to sustain damage against vibrations readily varies with respect to its strength and internal composition, which in turn is dependent upon several factors, like mix design, placement and curing method, and age of concrete. Hence to ensure the safety of concrete structures against blasting, the age of the concrete at the time of blasting was chosen as to be the governing factor to establish the safe vibrations limit for a concrete structure. The attenuation curve along with established safe PPV limits for the different ages of concrete helped establish guidelines which ensured the safe and timely execution of blasting activity at Gulpur hydropower project without any critical damage to the concrete.
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