兰州地铁穿黄隧道施工风险分析与控制措施

Countermeasures and Risks Analysis in the Construction of Yellow-River Tunnel in Lanzhou Subway

以兰州地铁1号线一期工程穿黄隧道的特点为基础,采用风险评估矩阵法R=P×L与德尔斐(Delphi)法、信心指数法从定性角度对穿黄隧道工程地质条件、盾构设备、施工管理等风险进行了识别、分析和评价,再采用层次法(AHP)从定量的角度对穿黄隧道施工各风险因素进行权重计算,通过定性和定量两种方法结合评定出了隧道开挖面失稳、刀盘被卡等风险因素的风险等级以及其造成的损失对工程建设的影响程度,并根据评估结果提出了相应的风险控制措施。研究表明只有准确的评价风险等级,才能制定安全经济的响应措施,有效的规避风险,使得工程建设顺利进行,同时也降低了工程成本,加快了工程进度。

Based on the geological conditions, surrounding environment and engineering characteristics of the Yellow- river crossing tunnel project for line 1 of Lanzhou Subway, this paper qualitatively analyses the potential risks of construction in the shield boring period from geological-conditions, shield-equipment and construction management, and researches the risk level of ten risk factors such as shied cutter-head trapped and excavation-face instability as well as their effects on the safety of the project by means of disaster risk evolution matrix method （R=PxL）. ＂Delphi ＂method and ＂confident-index＂ method, and the weight calculation of the risk factors of the construction of the Yellow River tunnel are carried out quantitatively by using Analytical Hierarchy Process （AHP）, the corresponding countermeasures for the risks so as to reduce the risk of construction in the shield boring on the basis of the analytical results. The research findings only evaluate the risk level accurately, and then work out safe and effective response measures, effectively avoid risks, so that the project construct smoothly, but also reduce the cost of the project, to speed up the progress of the project.