Test On Bearing Characteristics Of Root Anchorage And Simulation Analysis

The root foundation is a new type of bionic foundation.Due to the compaction and stress diffusion of the pushing root key,the contact surface between the foundation and the soil is increased,and the soil around the foundation is fully mobilized to bear the load force,which can effectively improve the bearing capacity of the foundation.Because the bearing mechanism of the root foundation and its surrounding soil is very complex,in order to deeply understand its bearing capacity characteristics,it is necessary to study its load transfer mechanism in practical engineering application by using a variety of methods.Based on the field test of anchorage construction of Chizhou Changjiang River Bridge Qiupu River Super Large Bridge,this paper analyzes the measured data and combines the results of numerical simulation The main research contents are as follows:(1)In the practical engineering application of the root anchorage,by installing the steel bar meter at different positions of the main reinforcement in the pile body of the root foundation,the stress change of the pile body in the process of the construction of the anchor can be tested,and the stress distribution law of the pile body of the root foundation in the engineering practice can be obtained.(2)Based on the design parameters of geotechnical engineering and the calculation formula of bearing capacity given by relevant projects,the total bearing capacity of root foundation and constant section pile foundation is calculated,and the calculation results are compared,which shows that the bearing capacity of root foundation is increased by9.7% compared with that of constant section pile foundation.By calculating the bearing capacity of the pile with constant cross-section,it can not bear the upper anchorage load,which further explains the necessity of applying the root foundation to the project.(3)The finite element software is used to simulate and compare the root foundation and the equal section pile foundation under the same working condition,and it is concluded that the root foundation is superior to the common pile foundation in displacement and settlement,axial force of pile body,etc.By comparing the measured stress value with the simulated stress value,the reliability of the experimental data can be verified,and the soil stress around the root foundation can be further studied.It can be concluded that with the increase of load,the soil stress around the root key changes significantly,and its role in improving the bearing capacity appears.