Modeling Technology and Stability Analysis of the Complex Bell-Shape Caverns
(1 Faculty of Geosciences and Environmental Engineering of Southwest Jiaotong University, Chengdu 610031; 2 State-Province Joint Engineering Laboratory of Spatial Information Technology for High-Speed Railway Safety, Chengdu 610031; 3 China Railway Academy Co. Ltd., Chengdu 610031)
Abstract：
Three-dimensional modeling technology is key to the numerical analysis of the stability of large irregu? lar cavern groups using Flac3D. Based on the multiple soft coupling technique, the rapid modeling of the complex irregular caverns of Changyu in Wenling of the Zhejiang Province is realized by comprehensive use of AutoCAD, Surpac, Surfer and Matlab programs under the condition of only using the main parameters of the cavern structure, such as the topographic map, center coordinate of the cavern bottom, tunnel height and tunnel span. A model that is 624m long, 480 m wide, 336 m high and has 6 irregular caverns is modeled with 16 m, 8 m, 4 m, and 2 m sized grids.Under the accuracy requirements, the calculation is completed in only 2.5 hours, improving the calculation speed greatly. The calculation and analysis show the cavern group is stable, but the force state of the surrounding rock at the bottom and the central diaphragm wall is not conducive to stability. Traditionally, there are three kinds of measures for enhancing the stability of the cavern structure during cavern excavation: partial removal of the surrounding rock at the bottom, storing water in the rock pit and partial removal of the rock mass at the central diaphragm.
2017, Vol. 54 