| With the rapid expansion of the scale of shield tunnel construction,the safety of its construction and operation periods will play a decisive role in evaluating the technical level of tunnel construction.The enhancement of the study on disaster prevention and reduction of tunnel is an effective measure to improve the safety of tunnel structures and reduce the risk of casualties and economic losses.Therefore,the study of the mechanical properties of tunnel lining under high temperature load is very necessary.The study of mechanical properties of shield tunnel lining under high temperature conditions and the analysis of its stress,deformation law and damage characteristics can provide a theoretical basis for the design,construction and maintenance of shield tunnels.However,the current research on the mechanical properties of tunnel under high temperature conditions are mostly limited to numerical method.There is still a lack of easy-to-operate and reliable test equipment,perfect test standards,and reasonable and effective test methods.Therefore,it is necessary to develop a shield tunnel ring structure test device that can apply thermal-mechanical coupled loads.Based on the results of previous studies and the theoretical knowledge of related disciplines,this paper has developed a device capable of realizing the experimental study of the shield tunnel under thermal-mechanical coupled loads.The specific work is as follows: Firstly,the study outline to divide the experiment device system into static loading system and temperature loading system was determined with reference to the previous research results.Secondly,the reasonable ranges of the central angle of test load were studied based on the numerical analysis.The whole static loading system can flexibly change the test loading mode.Meanwhile,the experimental method to build temperature loading system was proposed according to specific experimental device of tunneling rings.Finally,the design and building processes of that loading system were described based on the testing experiments.In order to verify the effectiveness of the experimental device,the testing experiments of experiment device of shield tunneling rings have been carried out.The test results show that the device can apply thermo-mechanical coupling load,and the loading method is simple,the data input and output are basically consistent with the theoretical and numerical analysis results,and the specific measures for further optimization of the device are proposed.In summary,the experimental device for shield tunneling rings under thermal-mechanical coupled loads developed in this paper provides an effective test equipment and test method for studying the mechanical properties of the tunnel lining structure at high temperature,and the failure process.It lays a foundation for the development of related research,and the research results have guiding significance for follow-up experimental research. |
