Abstract:

The tunnel maintaining and management basic principle of early discovery and preventive maintaining, which can achieve good results with less work, is emphasized. In order to establish the preventive management system, 3 issues, i.e. requirements for tunnel functions and tunnel function management target establishment, checking and investigation methods for accurate information and determination of modeled tunnel variation causes and standards. Based on the experience of tunnel maintaining and management in Japan, the abovementioned 3 issues are introduced as follows: 1) For requirements for tunnel functions, safe transit should be guaranteed and the variation should be controlled within the service life of tunnel structures. 2) For checking and investigation methods for accurate information, the developing directions of checking and investigation methods for accurate information are less labor, standardization, high speed and electronization; the investigation and measuring methods, i.e. tunnel measuring trolley, monitoring system, highspeed borehole drilling system, ground penetrating radar and 3D laser scanning device, for tunnel surface degradation, surface defect, internal defect, hollows behind lining, clearance displacement and deformation are introduced. The checking results are regarded as estimation of structure durability. [JP2]3) For determination standards and models of tunnel variation types and variation strength, the basic views of unconsideration of tunnel service life, service life prediction before carrying out treatments and methods, integrity estimation and countermeasures for preventive management, are introduced. It is emphasized that the tunnel maintaining and management methods and system in China should be removed; and a new type of tunnel maintaining and management system for China should be developed.

Key words: tunnel, mining method, preventive management, maintaining management, tunnel function, variation, investigation, judge standard