Full-Scale Test of the Early Performance of a Factory-Prefabricated Immersed Tunnel
1 School of Materials Science and Engineering, Tongji University 2 Department of Geotechnical Engineering, Tongji University 3 CCCC Fourth Harbor Engineering Institute Co., Ltd 4 Hong Kong -Zhuhai-Macao Bridge Authority
Abstract:
Due to large elements, complex structures and complicated construction technology, immersed tunnels are vulnerable to cracking under the influence of temperature and shrinkage and restriction during prefabrication, which are harmful to the serviceability and durability of the tunnel. This paper monitors the development of temperature and strain on the tunnel's key parts and compares relevant laws of temperature and strain development based on a full-scale test, using the immersed tunnel of the Hong Kong-Zhuhai-Macao Bridge Project currently under construction as an example. The results show that the immersed tunnel element structure will be subject to expanding and tensioning at the early age stage under a temperature rise induced by the hydration heat of concrete, then will shrink with the decrease of temperature after reaching the peak value; the element structure finally will be subject to compression because of autogenous concrete shrinkage.