Research on corrosion deterioration and failure process of shield tunnel segments under loads
Liu Sijin1 He Chuan1 Feng Kun1 An Zheli2
1. Key Laboratory of Transportation Tunnel Engineering of the Ministry of Education, Southwest Jiaotong University, Chengdu 610031, China;
2. China Academy of Railway Sciences, Beijing 100081, China
Abstract：In order to study the performance degradation of shield tunnel lining structure during the service period, based on the characteristics of shield tunnel lining under the long-term coupling effect of the water-soil load and the surrounding erosion environment, the stress states of shield tunnel segment were realistically simulated by the importing method of bending moment and axial force. Combined with the cofferdam-type electrochemical accelerated corrosion method, the test system which can achieve segment corrosion deterioration under loading conditions has been developed, and then the regularity of occurrence and development of corrosion deterioration of shield tunnel segments was analyzed under different conditions. The results show that: the fracture pattern of non-corroded segments reflects the main characteristics of transverse tensile cracks. In the accelerated corrosion stage, the corroded segments which are not loaded only produce corrosion crack along the reinforcement, and the crack width reflects the characteristics of the first increase and then tending to be stable; in addition, the concrete in corroded area tends to partially strip and dislocate under the combined effects of corrosion-induced expansion crack and tensile crack in the loading destruction stage. Crack propagation in segment under loading conditions is the result of the combined effects of corrosion of reinforcements and imposed loads, the collaborative occurrence and development of tensile cracks and corrosion cracks can be observed, leading to an obvious decrease in the bearing capacity of segments. The results can provide important reference and experimental data support for accurate evaluation on the long-term safety of shield tunnel in design reference period.
刘四进 何川 封坤 安哲立 . 受荷状态下盾构隧道管片锈蚀劣化破坏过程研究[J]. 土木工程学报, 2018, 51(6): 120-128.
Liu Sijin He Chuan Feng Kun An Zheli . Research on corrosion deterioration and failure process of shield tunnel segments under loads. 土木工程学报, 2018, 51(6): 120-128.
