Safety analysis of temporary anchorage system for immersed tube in Shenzhen-Zhongshan Link  

作　　者：Lei Yan Jinning Yan Guoping Xu Shuanhai He Zechen Zhang 

机构地区：[1]School of Highway,Chang'an University,Xi'an 710064,China [2]Key Laboratory of Transport Industry of Bridge Detection Reinforcement Technology,Chang'an University,Xi'an 710064,China [3]CCCC Highway Consultants Co.Ltd.,Beijing 100088,China

出　　处：《Journal of Traffic and Transportation Engineering(English Edition)》2024年第4期797-813,共17页交通运输工程学报（英文版）

基　　金：supported by the National Key Research and Development Program of China(No.2021YFB1600300)。

摘　　要：In the construction of the Shenzhen-Zhongshan Link,a temporary anchorage system,distributed uniformly along the pipe wall,has been employed.To assess the safety and reliability of this system,a combined method utilizing numerical analysis and model experiments was applied to study the safety of the temporary anchorage system and the reliability of the tension rods.Firstly,an overall model of the caisson segment based on GINA rebound force was established to analyze the stress state of the entire system.Secondly,a comprehensive numerical analysis and model experiment verification were conducted for the single tensioning system,revealing its failure mode and safety margin.The results indicate that the tension rod systems are uniformly stressed at an average of 444 k N during underwater jointing,with a safety factor of 1.94.At this point,the maximum von Mises stresses appearing at the front plate corners and the lower edge of the U-groove,with stress values of 181.8 MPa and 172.4 MPa,and safety factors of 1.54 and 1.71,respectively.When the tension rod force reaches 940 k N,the tensioning system reaches its bearing limit,with initial yielding occurring at the front plate corners.Model experiments were conducted to verify the theoretical analysis results,under a test load of 444 k N,the stresses at the front plate corners and the lower edge of the U-groove were 159.6 and 195.9 MPa,respectively.As the test load increased to 940 k N,these stresses reached 390 and 389 MPa,exhibiting good agreement with the numerical analysis.Considering the uncertainty of loads and materials,a reliability analysis of the tension rods was conducted,yielding a reliability index of 4.34,meeting the secondary safety standard.Based on the comprehensive analysis,it can be concluded that the temporary anchorage system in the caisson segments of the Shenzhen-Zhongshan Link exhibits excellent safety margins.

关 键 词：Tunnel engineering Immersed tube structure Anchorage system Full-scale model test Load bearing performance Safety assessment 

分 类 号：U459.5[建筑科学—桥梁与隧道工程]