非黏性土的振动密实试验研究(英文)

Study on densification of the non-cohesive soils

通过室内模型和现场振冲试验,研究了无填料振冲加固细砂吹填土的适用性。在模型试验中,进行了孔隙水压力测试和静力触探试验,研究了孔隙水压力变化规律和振冲间距对振冲效果的影响。通过回归分析,得出了孔隙水压力消散的经验公式。另外在现场进行了单点振冲,双点振冲及三点振冲试验。室内模型试验和现场试验的结果表明,无填料振冲法可以应用在细砂的地基处理中,并可以取得很好的效果。

The vibrofloation method without gravel backfill was thought to be proper only for treatment of medium and coarse sand with less than 10% fine particles. Almost no practical project is concerning vibrofloation without backfill treatment of fine sand. In this paper, a laboratory model test was then held to achieve the related characteristics of the hydraulic fine sand. In this test a reduced scale model was set up, in which pressure gauges were embedded. Based on the test data acquired during and after vibroflotation, the formula of porewater pressure dissipation is established. A series of cone penetration tests (CPT) had been made in the test. The insitu tests of single,double and trivibrofloations were conducted under the guidance of model test. According to analysis of results and insitu test model,vibroflotation has been proved to be satisfactory for the improvement of fine sand. 