Study On Risk Management In The Large-scale Tunnel Project During Construction

There are always a great number of uncertainties in tunnel construction dueto its characteristics, which feature complicated conditions and inadequateinfrastructural information, as well as limitation of methods, project duration andcost. These uncertainties, usually having a long impact throughout the wholeproject, result in incorrect invest strategy, thoughtless construction scheme,delayed completion, risk of personnel safety, financial loss, disorderedconstruction procedure and inefficiency, and are referred to risk factors ofengineering projects. Researches on related issues fall into the category of riskmanagement. During the construction of a tunnel, the process will be inevitablyaffected by a wide range of uncertain factors, giving rise to uncontrollability ofschedule, quality and cost, studies on which are focused on supersized tunnels.Authors consulted a great sum of literature and this paper is based on thefoundation of theoretic study and the Nanjing Weisan Road Cross-river TunnelProject (N Tunnel), investigating the accuracy and credibility of engineeringgeological survey, serviceability and reliability of design of shield machines andconstruction difficulties and accidents.Risk identification, analysis and evaluation have their own application scope,strength and weakness, and accordingly there are different measures to cope withthem. In engineering practice, proper methods and reasonable measures should bechosen in the light of the specific situation of the project. Based on the N Tunnelproject, this paper adopts classification method, decomposition of initial riskmethod and apriority method to identify risks, applies Fuzzy Analytic HierarchyProcess (FAHP) to risk analysis and evaluation, and applies comprehensivedecision-making method and dynamic control method to risk control, proposingcorresponding control measures for considerably high risk factors.This paper aims to equip engineering technicians with the capability ofidentifying risks of tunnel projects and estimating degree of risks more accurately, and to present improved risk analysis methods. The outcome of this paper canoffer technical support to risk and safety control on tunnel construction and sitemanagement, and be a good reference for similar projects.