Safe Blasting in Cement Limestone Quarries

(East and South-East Cairo)

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Abdel-Khalik A. S.[1], Zahran A. A.*, Albert R. N.[2],

Tantawi M. M.[3], Abdel-Hafiz S. S.[4]

ABSTRACT:

Blasting operations in quarries near to urban and residential areas are the source of many problems. This paper gives the solution of these problems. It summarizes some of the results obtained from a thesis related to four main quarries of relatively high annual production located East and South-East Cairo, namely: Egyptian Cement Company (ECC), Tora Cement Co. (TCC), National Cement Co. (NCC) and Helwan Cement Co. (HCC).

Blasting distance (R) and quantity of explosives per delay (Q) were related to the main damage criteria, namely: peak particle velocity (V), acceleration (a), energy ratio (ER), sound level (SL) and magnitude (m) in Richters.

Eighty blasting records of ECC quarry as well as 100 blasting records of Helwan observatory (HLW) were treated. Then, through computer modeling, propagation equations were derived to determine critical as well as safe limits of blasting in terms of Q and R.

Finally, the SL criterion was selected for use as the best criterion (having the least Q and the best correlation factor), to construct zoning maps of Q and R East and South-East Cairo (scale 1: 50000).

[1]  Tabbin Institute for Metallurgical Studies (TIMS)

[2]  Helwan National Institute of Astronomy and Geophysics (HLW)

[3]  University of Assiut

[4]  Ministry of Interior (MOI)