Karst Foundation Dynamic Treatment Research And Engineering Applications

With the development of highway construction in karst areas, the stability and deformation of embankment and foundation become prominent issues in engineering construction. The improvement of safety and reliability of highway in karst region is an important research problem in foundation treatment, therefore, Based on the significance of the dynamic compaction method for karsts cave in highway area, the dynamic compaction methods are introduced, and the stability of the cave is researched through the qualitative and semi-quantitative analysis according to the distribution of caves in engineering.The internal mechanism and the destruction ways are employed based on the distribution of caves in engineering.In the end, the experiment of engineering practice is studied, the studies which accumulates experience is employed for adopting strong compaction to deal with karst ground in the future. The main content is as follows:1. Based on extensive reading related books and scientific and technical literature both at home and abroad, the caves roof stability evaluation and consolidation mechanism and technical research are summarized up.2. Based on the collection and analysis of engineering background and engineering geological data of Loudi to Xinhua Highway of the 3th contract section, the actual shape and the distribution of the caves are analyzed, of their stability are detected with qualitatively interpretation to half quantitatively interpertation, the stress and deformation of caves and the surrounding rock and soil are also analyzed according to numerical simulation of the loads by the subgrade construction.3. Through the analysis and comparison of cave treatment programs, the purpose and requirements that dynamic treatment program need to achieve are pointed out. According to the hidden caves of the project, the main parameters of the dynamic compaction are designed.4. The best tamping energy is defined according to field experiment of engineering test section, the deformation of the foundation as well as the influencing depth and the scope under the effect of single and group tamping are studied, thus the reasonable parameter and technique are gotten with the method of cave foundation consolidation.5. The experiment and monitoring results were comparative analysised, according to the analysis effect with the method by DPT, the rationality and applicability of the dynamic consolidation method are verified.6. Based on the research of field test area, it provides guidance and reference for treating cave foundation areas of LX highway and the design and construction of similar engineering construction.