Abstract:In order to study the rationality of double-layer foundation pit calculation model, based on the case of the double-layer foundation pit section in the open excavated section of Guishui River Tunnel in Yanqing-Chongli Expressway (Beijing Section), through the comparison of calculation results of the two different calculation models and combined with the monitoring measurement results of foundation pit, it is put forward that the outer foundation pit can be calculated separately during the calculation of double-layer foundation pit, and the influence of outer foundation pit should be considered in the calculation model of inner foundation pit. It is not possible to simplify to load considerations only. The reference is hoped to provide for the similar projects.