block mass
6.Considering effect of damping ratio and frequency ratio to vertical amplitude of block foundation under dynamic action, this paper adopts calculating mode of mass-spring-damper and mass-spring to make account and analysis on the assumption of damping ratio and frequency ratio, then provides the range of damping ratio and frequency ratio by using two modes to calculate vertical amplitude of block foundation under dynamic action.
8.After the basic principles and analytic method of block theory have been introduced,they are used for the roof stability analysis of footwall houlage drift leved 570,in the stringerlode of Tongkeng Tin Mine Applying the block thery to the stability analysis of underground mines stope opening enriches rock mass structure analysis theory Besides,it opens up a new field, as an attempt,for the application of block theory,which is developing and improving continuously
