Mechanical model for Inverted arch of highway tunnel in weak surrounding rock and dynamic design

Due to the lack of theoretical basis for the design of inverted arch, the inverted arch design of many tunnels is not reasonable, and the problem is more prominent in the design of the shallow buried tunnel. By analyzing the relationship between the soft foundation and the stability of tunnel structure, the method of determining the load of shallow buried tunnel is presented. With the construction technology of the inverted arch, the mechanical model of the three- hinged inverted arch is established, and the formula for calculating the reasonable arch axis and the internal force calculation formula are given. The design procedure of inverted arch in shallow buried tunnel is presented, and the idea of dynamic design is introduced into the design of the inverted arch.