8PECK R B. Deep excavations and tunneling in soft ground[C]// Proceedings of the 7th International Conference on Soil Mechanics and Foundation Engineering. Mexico: [s. n.], 1969:225 - 281.
9MAIR R J, TAYLOR R N, BRACEGIRDLE A. Subsurface settlement profiles above tunnels in clays[J]. Geotechnique, 1993, 43(2): 315 - 320.
10LEE K M, ROWE R K, LO KY. Subsidence owing to ttmneling I estimating the gap parameter[J]. Canadian Geotechnical Journal,1992, 29(6): 929- 940.