Research on relationship between the development height of water conducted zones and the ratio of bedrock and mining under primary key stratum
According to the issue of varying development heights of water conducted zone with different ratios of bedrock and mining un-der primary key stratum(PKS),in order to determine the influence of the basic mining ratio under the PKS on the stability of the PKS and the development height of water conducted zones,a mechanical model of the overlying rock in the mining area was established on the basis of the theoretical model of the PKS,and the fracture mechanism of the key stratum was analyzed.Using UDEC numerical simu-lation software,two models for the variation of the ratio of bedrock and mining under the KPS were established.The conditions for the fracture of the KPS were analyzed,and the relationship between the height of the water conducted zone and the ratio of bedrock and min-ing under the KPS was studied.The research results showed that the height of the water conducted zone before and after the KPS was broken had different trends with the change of the ratio of bedrock and mining below the key stratum.The critical value of the ratio of bedrock and mining below the KPS when the KPS was broken was 7～10.When the ratio of bedrock and mining below the key stratum was less than 7,the KPS was located in the fractured zone.When the ratio of bedrock and mining below the key stratum was greater than 10,the main key stratum was located in the bending and sinking zone.
primary key stratum(PKS)water conducted zoneratio of bedrock and miningnumerical simulation
万方数据
维普
