Abstract Based on elastic mechanics, a nonlinear-cusp catastrophic model is built to research the safe distance between the working face and a concealed cave during excavation of a karst tunnel in accordance with catastrophe theory. Two models are established with the rock beam assumed to be an elastic beam with fixed and supported ends of unit-width and an elastic circular plate with fixed and supported periphery. Additionally, a formula is presented for the safe distance concerning catastrophe theory in a case where the working face is skewed or orthogonal to the karst cave with different sizes (i.e., the span of the karst cave is smaller or larger than the diameter of the tunnel),and the factors regarding the safe distance between the working face and the karst caves under the above different spatial states are analyzed. Based on a case study of the Shanghai-Kunming passenger dedicated line (the Guizhou section), it is determined that it is reasonable and feasible to use a cusp catastrophic model to describe the safe distance between the tunnel and concealed karst caves with different spatial states, and this model has certain guidance functions for the construction of karst tunnels.
Abstract：
Based on elastic mechanics, a nonlinear-cusp catastrophic model is built to research the safe distance between the working face and a concealed cave during excavation of a karst tunnel in accordance with catastrophe theory. Two models are established with the rock beam assumed to be an elastic beam with fixed and supported ends of unit-width and an elastic circular plate with fixed and supported periphery. Additionally, a formula is presented for the safe distance concerning catastrophe theory in a case where the working face is skewed or orthogonal to the karst cave with different sizes (i.e., the span of the karst cave is smaller or larger than the diameter of the tunnel),and the factors regarding the safe distance between the working face and the karst caves under the above different spatial states are analyzed. Based on a case study of the Shanghai-Kunming passenger dedicated line (the Guizhou section), it is determined that it is reasonable and feasible to use a cusp catastrophic model to describe the safe distance between the tunnel and concealed karst caves with different spatial states, and this model has certain guidance functions for the construction of karst tunnels.
SHI Hai- 1 Bai-Ming-Zhou- 1,
2 Xu-Zhao-Yi- 1 Tian- Gang
.Analysis of the Safe Distance between a Karst Tunnel and a Concealed Karst Cave Based on Catastrophe Theory[J] MODERN TUNNELLING TECHNOLOGY, 2016,V53(4): 61-69
2016, Vol. 53 