公路工程

大量实践表明，高水压岩溶隧道施工发生突涌危害性极大。云南省华丽高速公路营盘山特长隧道属于典型的高压富水岩溶隧道，突泥涌水灾害频发，施工处治难度大、安全风险极高。针对施工过程中遭遇的前所未有的隧道出口端188持续性大规模突涌淹井事件和进口端916、924重大突涌，进行理论研究、方案制定、实践检验与过程总结，提出应对策略和关键技术：1）针对安全岩柱厚度的确定，要采取多种理论进行分析对比，优先采用塑性区贯通准则理论取值2-3倍的安全系数，并结合现场超前试钻探进行综合确定，把握安全合理和经济高效的原则；2）针对188持续性大规模突涌淹井，采取“搁置斜井、正洞高压泄水、分阶段实施、稳步逼近斜井水体”的正洞分阶段高压泄水方法，完成最终泄水，攻克淹井长达两年的降排水难题；3）针对长时间浸水的洞身淹没段的处治，采取“分段分层清渣+临时护拱加固+径向注浆加固，循环作业，逐步推进”的处治措施，安全穿越涌水段。针对初支浸泡和挤压变形处治，采用“台车法”换拱，“微爆破+破碎锤+风镐”三者配合，快速完成换拱处治；4）针对916和924顽固性涌泥涌渣处治，采取横洞迂回，越过不良地质段，正常掘进并反向处治，实现正常掘进。

Extensive practice has shown that the occurrence of sudden surges during the construction of high water pressure karst tunnels poses great harm. The Yingpanshan Extra-long Tunnel on the Huali Expressway in Yunnan Province is a typical high-pressure and water-rich karst tunnel， with frequent mud and water inrush disasters， difficult construction and treatment， and extremely high safety risks. In response to the unprecedented large-scale surge flooding event at the exit end 188 of the tunnel and the major surges at the inlet ends 916 and 924 encountered during the construction process， theoretical research， scheme formulation， practical testing， and process summary were conducted to propose response strategies and key technologies: 1) For the determination of safe rock column thickness， multiple theories should be adopted for analysis and comparison， with priority given to using the plastic zone penetration criterion theory with a safety factor of 2-3 times， and combined with on-site advanced trial drilling for comprehensive determination， grasping the principles of safety， rationality， and economic efficiency; 2) In response to the continuous large-scale surge flooding of the 188 well， the method of "shelving the inclined shaft， high-pressure discharge from the main tunnel， phased implementation， and steadily approaching the inclined shaft water body" was adopted to complete the final discharge and overcome the drainage problem of the flooded well that lasted for two years; 3) For the treatment of the submerged section of the tunnel body that has been submerged for a long time， the treatment measures of "segmented and layered slag removal+temporary arch protection reinforcement+radial grouting reinforcement， cyclic operation， gradually advancing" are adopted to safely cross the water inflow section. For the treatment of initial immersion and compression deformation， the "trolley method" is used to replace the arch， and the combination of "micro blasting+crushing hammer+air pick" is used to quickly complete the arch replacement treatment; 4) For the treatment of stubborn mud and slag surges in 916 and 924， a transverse tunnel detour was adopted， crossing the unfavorable geological section， normal excavation was carried out， and reverse treatment was carried out to achieve normal excavation.