Abstract:

The Xiamen Wuchun highway tunnel of which the span is 34.5 m and only 9 m buried depth, passing underneath an area over 95 sets of buildings within it, the geological condition and environment of the tunnel is very complicated; and the degree of difficulty being under construction is immense also. In order to solve the main security risks during tunnel construction, such as uneven settlement, deformation and destruction of building, we conducted comprehensive research approaches and adopted a set of comparatively perfect safety management system. Firstly, we simulated excavation and reinforce of tunnel construction by using numerical method, and get the deformation values on key construction step. Combining with experiences from other similar projects and national standard, we drew out the control standard values for security monitoring to guide the tunnel excavation and the building protection. Secondly, we carried out thoroughly monitoring to grasp the dynamical response of building, pipeline, ground surface, stratum, surrounding rock and lining of tunnel during construction to ensure security, and implement 24 h automatic monitoring to the key buildings. Thirdly, having built advanced network transmission system of security management, which include monitoring information management, forecasting system and the information announces system with LED display screen; the whole monitoring data and construction proceedings can be stored and processed in data base server, while can be browsed and inquired by the networked computer. Finally, based on the work of third-party monitoring, we built a kind of monitoring management system of III levels warning, which can announce the warning information and construction proceeding to all participant via intranet or LED screen in time.

Key words: shallow-buried large-span tunnel, security risk, intensive buildings, information management system, automatic monitoring