冲击碾压处理滨海粉细砂地基试验研究

Experimental Research on Treatment of Silty fine Sand Foundation with Impaction and Grind Method（IGM）

摘要:

依托海南省某滨海旅游公路，利用标准贯入试验、重型动力触探试验等原位测试和压实度、弯沉等检测结果，以及地下水位、孔隙水压力和地表沉降等实时监测数据，对滨海粉细砂地基进行冲击碾压的试验研究，探讨冲击碾压处理滨海粉细砂地基的有效性以及合理的施工工艺.研究结果表明，采用冲击碾压有效处理粉细砂地基的关键在于以浅层饱和粉细砂地基中超静孔隙水压力消散率至少达到70%作为实施下一轮次冲碾的控制标准.合理的施工工艺不仅能有效提高粉细砂地基强度，而且可消除浅层粉细砂地基的液化.冲击碾压后，2 m深度范围内粉细砂地基土的压实效果显著.

Abstract:

Based on a coastal tourism highway of Hainan Province， an experimental research was made into the treatment of silty fine sand foundation with impaction and grind method (IGM). In situ tests (SPTs, DPTs), compaction test, deflection test and real time monitoring data of groundwater level, pore water pressure and surface settlement were adopted to discuss the effectiveness and construction technology of the silty fine sand foundation with the impact roller compaction method. The results show that the key to an effective treatment of silty fine sand foundation with impaction and grind method is to take the excess pore water pressure dissipation rate at least 70% in saturated silty fine sand shallow foundation as the control standard of next round of the impact roller compaction. The reasonable construction technology not only can effectively improve the strength of silty fine sand foundation, but also can eliminate liquefaction shallow silty fine sand foundation. After the treatment, the subsoil up to the depth of 2 m is well improved.