Abstract In this study, based on the shield tunnel project underpassing the boulder section from Hengli Station to Wanqingsha Station along the southern line of Guangzhou Metro Line 18, the boulder prospecting and the preprocessing technology are studied. In this paper, a set of precise location and prospecting technologies are proposed, in which the HSP horizontal acoustic wave/seismic wave profile method and the virtual source method are jointly used to quickly detect the development range of boulder body, and the geological drilling method is used to determine vertical and transverse boundaries of the boulder. This reduces the geological drilling and prospecting work, and then the blasting of the boulder revealed by geological drilling is allowed. The results show that the proposed boulder prospecting method is advanced and reliable, and it is allowed to detect boulders in time, reduce the prospecting cost, and shorten the construction period; in this method, the design of blasting parameters are designed reasonably,and the boulder section is processed well; the average tunnelling speed in the boulder section after blasting along left and right lines is 34.63 mm/min, which is close to the average tunnelling speed in the conventional strata.
Abstract：
In this study, based on the shield tunnel project underpassing the boulder section from Hengli Station to Wanqingsha Station along the southern line of Guangzhou Metro Line 18, the boulder prospecting and the preprocessing technology are studied. In this paper, a set of precise location and prospecting technologies are proposed, in which the HSP horizontal acoustic wave/seismic wave profile method and the virtual source method are jointly used to quickly detect the development range of boulder body, and the geological drilling method is used to determine vertical and transverse boundaries of the boulder. This reduces the geological drilling and prospecting work, and then the blasting of the boulder revealed by geological drilling is allowed. The results show that the proposed boulder prospecting method is advanced and reliable, and it is allowed to detect boulders in time, reduce the prospecting cost, and shorten the construction period; in this method, the design of blasting parameters are designed reasonably,and the boulder section is processed well; the average tunnelling speed in the boulder section after blasting along left and right lines is 34.63 mm/min, which is close to the average tunnelling speed in the conventional strata.
LU Shaozhuang ZHAO Lu GUO Zhifeng
.Study on Precise Geophysical Prospecting and Processing Technique for Large-diameter Shield Tunnelling Through Coastal Boulder Strata[J] MODERN TUNNELLING TECHNOLOGY, 2023,V60(5): 195-204
2023, Vol. 60 