振冲砂桩复合地基单桩最优桩间距的确定

FIELD TESTS ON RATIONAL SPACING BETWEEN VIBROFLOTATION SAND PILES

摘要: 通过现场振冲砂桩施工及标贯试验,围绕振冲砂桩复合地基砂桩的合理间距开展了试验研究。结果表明在本文各种试验工况中, 1.4m工况的桩间距为振冲砂桩施工的最优间距。分析认为对于振冲砂桩施工法而言,当地层条件、振动力、振动频率及施工工艺一定时,实际密实效果主要与桩间距有关。在与本文试验场地条件相似的场地进行振冲砂桩复合地基施工时,对于桩径为1m的砂桩,其设计桩间距至少应控制在1.6m以下。同时指出,由于振冲砂桩的制桩成本较小,因此在实际施工中应尽量采用小间距以获得更好的挤密效果。本文得出的结论为沙漠地区振冲砂桩复合地基的设计和施工提供了重要的参考依据。

Abstract: Based on the field SPT,the Rational Spacing between Vibroflotation sand Piles in Aeolian Sand of the Mu Us Desert is studied in this paper.The results show that the spacing of 1.4m was the most effective pile spacing.It is suggests that the compaction effects mainly depend on the pile spacing under the same conditions of sand layers,vibration force,vibration frequency as well as the construction technology.In the case of the tests in this paper,where the diameter of the tested sand piles is 1m,the pile spacing should be controlled within 1.6m.Considering the inexpensive of the sand pile construction,the small pile spacing is recommended based on the analysis of the tests.