Abstract

Defining the region which effected by the elastic reaction force of underground construction had the important meaning for the calculation of underground structure’s section force. The effective of elastic reaction force makes slight the working of underground structure, controling their deformation, increasing numeric value of axial force and decrease the value of bending moment of structure. For the previous time, by the experiment calculation, the angle which define the region had not effected by the elastic reaction force of ground foundation is: ϕ0 = π/4 . In this research, we build the code of Matlab programme to compute the underground construction by Finite element method, making a iterative calculation to define the ϕ0 angle with the purpose to define exactly the region of elastic reaction force of underground structure, at the same time, making a computation of section force value of the underground structure.