PARAMETRIC MODELLING OF THE GEOLOGICAL CROSS SECTION FOR SHIELD TUNNEL DESIGN AND CONSTRUCTION

Abstract

Geological information is indispensable for the design and construction of underground structures, especially for large-diameter shield tunnels. The geological cross-section is expected to be accurately and efficiently modelled to provide sufficient geological information for decision-making. However, the existing methods are usually time-consuming, and the calculation results cannot be intuitively understood by engineers. To meet this demand, this study attempts to develop a parametric modelling approach for the geological cross-section of tunnelling construction. The proposed approach consisted of four steps. In the first step, the borehole records from the geological investigation are converted into the DataFrame format. Then, each point is assigned a soil type label and soil property parameter to form a data framework. In the third step, the cross-section is generated in mesh type and divided into two parts. Finally, the mesh models are rendered to visualize the stratum sequence and soil property distribution. The proposed approach is applied to Lianghu tunnelling construction in Wuhan, China, for verification. The results show that the 11 geological cross-sections with ground water surfaces can be automatically modelled within 25 seconds, including stratum sequence identification and ground pressure calculation. The calculation results could be successively used in the tunnel structural analysis. Therefore, the proposed approach potentially promotes a data-driven technology for underground engineering construction.