关键词: 沉管接头, 漏水, 模型试验, 红外监测

Abstract: In the application of immersed tube tunnel, water leakage has become a vital problem both in the construction and in the period of operation. For this reason, laboratory experiment is carried out to simulate the seepage of immersed tube tunnel joints of Hongkong-Zhuhai-Macau Bridge by building a full-scale model. By applying infrared technique to the contactless detection of invisible leakage water, monitoring system can collect data of infrared radiation image which is then analyzed with Matlab. Temperature jump method is adopted by analyzing the change of infrared signature, to make the judgment whether leakage happens behind OMEGA or not. Influencing factors on the judgment are analysed at the same time. Results of the experiment show that infrared techniques can be used to monitor sudden leakage of immersed tube joints with the temperature jump method. Relatively large temperature difference between sudden leakage water and structure of joints will lead to temperature jump on the surface of structure. The larger the temperature difference is, the less time system needs to make a judgment. The experiment provides a possible method for application of infrared technique in immersed tunnel and other projects. Feasibility of application of infrared technique in immersed tube joints is researched.

Key words: joints of immersed tube, leakage water, model test, infrared monitoring