Interaction between karst-subsidence foundation and subgrade in Lou-Xing freeway and its treatment methods

Based on analysis of environmental geological conditions and disaster-forming mechanism karstic ground subsidence is considered as a result of common function of water cone forming caused by forced drainage, earth-cave forming induced by karstic mine mud-burst, devaluing of shear strength of cover layer caused by occasional heavy rainfall and so on.

Research purposes: The discussion on karst ground collapse in the engineering construction of the high speed railway is carried out to find out a relatively economic,rational and reliable karst collapse regulation principle.

The authers apply the method of grey system model to research into the division and prediction of Karst ground collapse.

The karst surface collapse in Wuhan happened at the intersection between the NE first terrace binary-structured deposits of Yangtze River and carbonate in the core of E-W syncline.

This paper analyzed the formation mechanisms of karst collapse in this region, and put forward corresponding countermeasure to prevent and control the karst collapse from the three aspects-organization, policy and technology.

Karst collapse is usually caused by overdrafting karst groundwater.

Taking Tai\'an as an example,the forming mechanism of karst collapse is discussed in this paper.