The Application Of Dynamic Compaction Method In Foundation Treatment And The Parameter Study

After dynamic compaction method was proposed for the first time since 1968, the theory research and engineering application at home and abroad, but is not yet formed a set of generally accepted theoretical design and calculation method.Combined with the engineering geological conditions of one project in Handan, a detailed analysis of the dynamic compaction method to deal with the foundation, the reinforcement mechanism of the system construction, the design parameters of the dynamic compaction method, and the study, on the basis of detecting effects are simulated and analyzed various influence factors of dynamic compaction treatment effect.(1) In this paper, through the analysis of the dynamics of soil consolidation theory and the theory of shock wave pressure, the effect mechanism of dynamic compaction method to reinforce foundation has carried on the deep discussion.Combined with a project in Handan area, detailed study of the dynamic compaction method design steps, the determination method and its parameters for trial ramming, through static load test to detect the effect after dynamic compaction, meet the needs of the project, on the basis of engineering with ram, tested up to the foundation treatment effect.(2) The use of the geotechnical software FLAC3 D numerical simulation in this engineering example, through to click in the process of tamping ramming heavy volume, observation of changes of stress, strain and the plastic zone and the consolidation process, by changing the fall away from the size of the to analyze different when a foundation is improved with the tamping can change law of general tamping can choose a little short of reinforcement effect, too big and will increase the cost, in view of the silty clay or artificial filled soil tamping can increase to 1000 kn m., its influence depth of about 1 m.(3) Analyze the results of numerical simulation shows that the point of ramming its maximum vertical displacement of foundation soil, the tamper hole around the center of the soil as ramming the farther the distance of the smaller amount of ram sink, tamping for 3000 kn m. when the level of influence range is based on ramming point as the center circle, 3 m in diameter than the distance when there is almost no change, therefore, should be reasonable arrangement of tamping point spacing, neither too much spacing between the tamping points can not get effective reinforcement of soil, and not too small cause waste of resources.(4) Along with the increase in number of tamping soil plasticity change more and more small, soil consolidation effect is not tamping the more the better, tamping times less, reinforcement effect is not obvious, tamping times too much will cause the waste of resources, determine the optimal number of passes to avoid resource waste, the engineering optimum tamping times for 7 times.In this paper, the design theory and numerical simulation of the dynamic compaction method for more in-depth research, research in the future the theoretical research and engineering application of dynamic compaction method has certain reference significance.