昆明轨道交通4号线岩溶发育特征及治理措施

滇池盆地地质条件复杂，多处分布可溶岩，岩溶问题突出，对昆明轨道交通工程影响很大。轨道交通工程岩溶的勘察需经过多阶段采用综合勘察技术才能查清其特征、性质及危害。经勘察及分析，昆明轨道交通4号线大河埂站-大塘子站段、呈贡东站（含）-昆明火车南站段岩溶弱发育，联大街站-呈贡东站区间、白龙潭停车场及出入段线岩溶中等发育，金鼎山站-小菜园站段岩溶强烈发育。4号线为覆盖型岩溶，岩溶主要发育于基岩面下15m范围，并以0.5~3.0m洞高的充填型溶洞为主，钻孔平均遇洞率21%，平均线岩溶率3.29%。综合将岩溶区划分为稳定区、次不稳定区和不稳定区。岩溶治理应针对不同的工程类型和岩溶特征采取相应的处理原则和工程措施。岩溶治理一般采用注浆加固措施，对于埋深较小的岩溶可采取开挖揭露回填注浆进行加固处理，桩基需穿过岩溶置于下部稳定地层中。文章对昆明地区轨道交通岩溶勘察及治理具有一定指导作用。

KARST CHARACTERISTICS AND GOVERNANCE MEASURES IN KUNMING METRO LINE 4

The geological conditions of Dianchi Basin are complex, and soluble rocks are distributed in many parts of the basin and the edge of the basin. The Karst problem is prominent and has a great influence on metro. The investigation of Karst in metro needs to be carried out through multiple stages using comprehensive survey technology to find out its characteristics, properties and hazards. After investigation and analysis, the Karst weak development of the Dahegeng Station of Kunming metro Line 4~Datangzi Station Section, Chenggong East Station(including)~Kunming South Railway Station Section, Liandajie Station~Chenggong East Station Section, Bailongtan parking lot and the Karst middle development of the entrance and exit section line, The Karst section of Jindingshan Station~Xiaocaiyuan Station developed strongly. Line 4 is covered Karst. Karst mainly develops in the 15m range below the base rock surface, and is dominated by filled caves with a height of 0.5~3.0m. The average hole rate of boreholes is 21%, and the average line Karst rate is 3.29%.The Karst area is divided into stable area, sub-unstable area and unstable area. Karst management should adopt corresponding treatment principles and engineering measures for different engineering types and Karst characteristics. Karst treatment generally adopts grouting reinforcement measures. For Karst with a small buried depth, excavation to expose backfill grouting can be used for reinforcement treatment. The pile foundation needs to pass through the Karst and be placed in the lower stable strata. This paper has some guidance for the Karst survey and treatment of metro in Kunming.