Method for testing mechanical property of uplift pile under deep excavation condition

Abstract

The invention relates to a method for testing mechanical property of an uplift pile under a deep excavation condition. The method comprises the following steps: (1) building a vertical tension mechanical model of a base-enlarged uplift pile by utilizing a numerical value analysis method, a centrifugal model test, a limit equilibrium method and a limit analysis method; (2) acquiring failure mechanism and load bearing characteristics of a uniform-section uplift pile and the base-enlarged uplift pile, and uplift bearing capability loss characteristics of the piles under excavation unloading based on the centrifugal model test and numerical simulation; (3) proposing three calculation methods of bearing loss of the uplift pile under a predicted deep excavation condition; and (4) determining a critical failure surface by utilizing an improved Monte-Carlo search technique, building a multi-block upper limit analysis method for a limit bearing capability of a base-enlarged uplift pile to obtain data of the mechanical property of the uplift pile under the deep excavation condition. Compared with the prior art, the method for testing the mechanical property of the uplift pile under the deep excavation condition, disclosed by the invention, has the following advantages of optimizing design and construction schemes, saving engineering investment, improving an analysis theory of the uplift pile and the like.

Description

technical field [0001] The invention relates to the mechanical properties of uplift piles under deep development conditions, in particular to a test method for the mechanical properties of uplift piles under deep excavation conditions. Background technique [0002] With the development of urban construction, the application of uplift piles is becoming more and more extensive. The fields of application mainly include construction projects such as housing construction, roads and bridges, offshore and coastal projects, and power transmission and transformation projects. However, so far, most of the research on uplift piles is based on the top of the piles buried on the surface or in a shallow underground position. For the largest underground substation project in Asia, the Shanghai World Expo 500kV large-scale underground substation project (hereinafter referred to as the Expo underground substation project), such a class of large-scale projects, is facing a new issue of uplift...

AI Technical Summary

Problems solved by technology

[0004] Previous studies have shown that the failure mode of medium and long uplift piles in the Shanghai area is often in the form of small-angle expansion. Theoretical Analysis and Experimental Research

At present, there is no systematic research based on the combination of field test results analysis, centrifuge model test, theoretical analysis and numerical simulation.