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Abstract On the basis of the main factors affecting the test of ground shock induced by explosion，the empirical formulae of ground shock parameters are deduced by means of dimensional analysis. With the data of field tests in sandy clay，the attenuation curves of peak stress which is an important parameter of ground shock at different scaling depths of burst(SDOB) are drawn out. It can be concluded from the curves that the SDOB，ranging from －0.20 m/kg1/3 to 1.00 m/kg1/3，has great influence on peak stress of ground shock；and the tendencies of attenuation curves of peak stress at different SDOB are in concert. That is to say，the empirical formulae of peak stress at different SDOB have the same attenuation exponent；and the attenuation coefficient of empirical formulae will enlarge with the increasing SDOB. When the SDOB are close to 0.80 m/kg1/3，the space between the attenuation curves of peak stress of ground shock is already very small，which indicates that SDOB have no obvious effect on the parameters of ground shock after it reaches 0.80 m/kg1/3. When two explosions at different SDOB in one medium produce the same ground shock magnitudes in the same scaling distance，the relationship between the explosive charge with different depths in the yield of above two explosions is defined by“DOB coefficient of equivalent yield”. According to the attenuation law of peak stress，the prediction method of ground shock parameters in free field at different SDOB in sandy clay has been given with DOB coefficient of equivalent yield，which provides the computing method of explosion load for the antiknock study and structure design during underground construction.
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Received: 15 April 2011
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2011, Vol. 30 
