MEASUREMENT AND ANALYSIS OF THE EFFECT OF GROUND VIBRATIONS INDUCED BY BLASTING AT THE LIMESTONE QUARRIES OF THE EGYPTIAN CEMENT COMPANY

ABSTRACT- Ground vibrations and airblasts are part of the output of the blasting operations. which have an impact on the environment. When their levels are high, they can cause human annoyance, discomfort, and even cause damage to nearby structures. Hence, measuerment of ground vibrations and airblast levels and use of published damage criteria are necessary to judge the design of the blasting operations if it complies with the safe regulated levels or it does not. The Egyptian Cement Company (ECC) plant is located about 3 km north of km 93 Elmaadi-Elsukhfla road (about 70 km South West of Suez). The objective ofthis paper is the measurement and evaluation of the level of groundvibrations and airblast over pressures induced by blasting at the limestonequarries of the ECC. This objective has been attained through extensive plan of measurements. Fifteen blasts covering all the working faces, have been monitored using nine modem seismographs. Measurements have included the maximum magnitudes of the three mutually perpendicular components of the peak particle velocities, airblast over pressure levels as well as recording complete wave traces of vibrations. Also, effect of the explosive initiation method on ground vibrations and airblasts has been investigated. The ivestigation has been carned out for different charge weights at various distances. These measurements and records have been analized to provide propagation laws for ground vibrations and airblasts. These propagation laws are important for the quarry manager and engineer to predict the level of ground vibration and airblast before carrying out the blast