Microtremor Test in Heidaigou Mining Area and Its Analysis
During the mining process of the Heidaigou open-pit coal mine,strong surface vibration was generated due to the use of large doses of thrown blasting.Since the mining area is covered with tens of meters of loess,studying the amplification effect and predominant frequency of the loess covered site in this area has important theoretical and practical significance for coal mining design.Firstly,based on the field survey,we selected the bedrock surface and loess site of No.1 mining area of Heidaigou Open-pit Coal Mine to carry out microtremor tests,and obtained the acceleration time history of the bedrock and loess site.The test data was analyzed by Fast Fourier Transform and Single Point Spectral Ratio.The results show that the magnification factor of the loess site in this area is about 2.7 times,and the predominant frequency is about 2.3Hz.Secondly,a FLAC one-dimensional soil column model is established based on the actual measured data of the site,and the acceleration time history of the bedrock is used as the input to calculate the micro-vibration response of the loess site.The calculated results are basically consistent with the results of the microtremor test.
万方数据
维普
