Abstract:

The pretreatment for the contact surface of the composite structure in underground engineering by conventional roughening method is characterized by large construction difficulty and uneven shear groove setting. As a result, a prefabricated composite structure form is proposed. And then the finite element software ANSYS is used to analyze the forces of the wave, triangle and trapezoidal corrugated structure planes, and the results show that the trapezoidal structure plane is superior to the other two in terms of structural stress, interface pressure and contact surface slip; the trapezoidal structure plane is chosen for the static load test. The deflection, horizontal displacement and crack development of the cast beam and trapezoidal structure surface composite beam under different loading levels are analyzed by static load test; and the monitoring data show that: Under the same loads, the deflection increment of composite beam is less than the cast beam; and the composite beam stagnates during crack development stage, which can mitigate the crack go cross the composite surface, and further improve the bearing capacity of the structure.

Key words: underground engineering, deep and largescale foundation pit, composite structure, numerical simulation, static test