关键词: 贝叶斯网络, 隧道, 围岩失稳, 风险预警, 专家系统

Abstract: Based on the concise analysis of the influence of support parameters to stability and deformation of surrounding rock mass in soft rock tunnel, Bayesian network and corresponding uncertainty reasoning principle has been introduced to develop an expert system for selection of support parameters of soft rock tunnel with large span. By combining prior knowledge of domain experts with work-site data recorder, the paper gets the posterior probability density of most nodes. The expert system is applied to compare several schemes about the support parameters of one tunnel. The field practices prove that the expert system has good applicability. The Bayesian network can reason the incomplete input information by using the prior knowledge of domain experts and work-site data recorder. The Bayesian network based expert system can not only be applied to making comparison and choice of the support parameters of soft rock tunnel, but also be applied to diagnosis of the collapse accident of soft rock tunnel.

Key words: Bayesian network, tunnel, surrounding rock instability, risk early-warning, expert system