深竖井突水风险动态评估与施工许可机制研究

Study on the dynamic assessment of water inrush risk and the construction license mechanism of deep shaft

为控制深竖井施工突水灾害,通过理论研究与实例分析,建立了基于地质勘察、施工因素和动态反馈信息有机结合的三阶段评估方法,采用综合赋值法对深竖井突水影响因素进行权值分析,建立了深竖井施工许可机制。结果表明,不良地质、地下水、断裂破碎带、导水通道、超前地质勘察是影响深竖井突水风险的主要因素,其次为围岩级别、开挖支护、监控量测、宏观征兆,岩层产状、隔水层厚度、应力水平、管理水平和微观前兆对深竖井突水影响较小。三阶段评估包括初次评估、二次评估和动态评估,初次评估是基于地质勘察、施工前的准备,二次评估是对施工组织合理性的评价,动态评估是基于动态反馈信息进行施工方案动态调整的评估方法。基于动态评估建立的施工许可机制实现了信息的共享,综合了业主、监理和施工单位的意见并及时进行施工方案的修正,是规避和控制风险的有效途径,为相关工程提供指导。

In order to control water inrush risk of deep shaft,through statistical and theoretical analysis of relevant engineering projects,three-stage assessment is proposed based on geological investigation,construction and dynamic feedback information.Factors＇weights are studied based on composite valuation method.The construction license mechanism of deep shaft is established.Analysis results show that unfavorable geology,underground water,fracture zones,water guiding passage and geological prediction are the main control ingredients of water inrush risk.Surrounding rock mass classification,excavation and supporting,monitoring measurement,macroscopic geological precursory information are the minor significant factors;attitude of rock formation,thickness of water resisting layer,stress level,management level and microcosmic precursory information are the least important elements.The three-stage risk assessment method includes preliminary,secondary and dynamic assessment of water inrush risk.Preliminary assessment is based on geological investigation and preparation before construction.Secondary assessment isevaluation of rationality of the construction organization.Dynamic evaluation is the evaluation of dynamic adjustment based on dynamic feedback information.Construction license mechanism that combined with ideas of owners,supervisors and construction units realizes information sharing and provides guidance for the related projects.It is an effective way to avoid and control water inrush risk of deep shaft.