广清高速公路改扩建工程岩溶发育特征及碳酸盐岩溶蚀特性试验研究

广清高速公路改扩建工程项目线路有33 km是岩溶区，岩溶区内塌陷普遍存在。以新华高架特大桥桥位段为研究对象，从研究区的工程地质条件、水文地质条件、岩溶发育特征等入手，通过室内模拟溶蚀试验，探讨该工程沿线岩溶发育及塌陷产生的原因。研究发现:该区域岩溶强烈发育地区石灰岩裂隙发育，强度较低；多为微晶和生物碎屑灰岩；在地下水的作用下，极易发生溶蚀，且溶蚀速率较大；碳酸盐岩类岩石在静态水介质中的水岩反应过程，总体上表现出随时间的增加其溶蚀速率不断衰减的趋势。

Experimental Study on Karst Development Characteristics and Dissolution Characteristics of Carbonate Rocks in Guangzhou-Qingyuan Highway Renovation and Expansion Project

Guangzhou-Qingyuan highway renovation and expansion project has karst area of 33 km. And collapse is widespread in karst area. To explore the causes of karst and collapse around the project, we have analyzed the engineering geological conditions, hydrogeological and geological conditions, karst development characteristics at Xinhua viaduct bridge, and carried out the dissolution test of the rock. It is found that the limestones have a lot of cracks and a low strength in karst development area. Most of them are microcrystalline and bioclastic limestone. And dissolution occurs easily under the action of groundwater, with high speed rate. The dissolution velocity of carbonate rock in static water is becoming more and more small with the increase of time.