Method and system for determining ultimate support pressure of tunnel shallow-buried shield excavation face

The invention relates to the technical field of tunnel engineering, and discloses a tunnel shallow-buried shield excavation face limit support pressure determination method and system.The method comprises the steps that a numerical model of a shallow-buried shield is built, and a combined curved surface body model in the tunnel excavation process is built; constructing a first model based on the circular truncated cone region model, and constructing a second model of multi-layer soil and considering underground water level vertical soil pressure on the basis of the first model; constructing a third model based on the arc turning region model, calculating the internal energy loss power in the arc turning region model according to the third model, and calculating the internal force and external force power of the arc turning in the arc turning region model according to the third model; calculating the vertical pressure power in the circular truncated cone region model based on the second model, and calculating