西北干旱湿陷性黄土区增湿高能级强夯试验研究

研究目的:西北干旱湿陷黄土区土体含水量较低,一般在3%～8%之间,在现行规范的能级(8 500 kN.m)下直接进行强夯,影响深度比较小,都需要进行增湿处理。目前,采用高能级(大于10 000 kN.m以上)对西北干旱湿陷黄土地基进行强夯处理的案例较少,而采用增湿联合高能级强夯处理湿陷性黄土地基更是鲜有报道。为此,在国家建设大型储罐的基础上,开展15 000 kN.m直接高能级强夯和增湿联合15 000 kN.m高能级强夯试验对比研究,以期探索出一条适宜于西北干旱湿陷性黄土区增湿联合高能级强夯地基处理的施工工艺。研究结论:试验研究表明:在西北干旱湿陷黄土区直接进行15 000 kN.m高能级强夯、增湿联合15 000 kN.m高能级强夯消除湿陷的深度分别可达9.5 m、15.5 m,其强度参数均有近2倍以上的提高。通过这一试验,探索出一条适宜于西北干旱湿陷性黄土区增湿联合高能级强夯地基处理的施工工艺,可以为类似工程的地基处理提供借鉴。

Experimental Research on the High Energy Level Dynamic Compaction with Humidification Operation to Collapsible Loess in the Arid Region in Northwest China

Research purposes: The collapsible loess in the northwest arid area is relatively dry,and its moisture content is 3 to 8%,so it is generally believed that it is needed for humidification treatment with the energy level(below 8 500 kN·m)in the current specification standard to treat collapsible loess found directly because of the effect of poor compaction,relatively small effect depth.At present,it is less than that the dynamic compaction with more than high energy level(more than 10 000 kN·m) to collapsible loess in the arid region in Northwest China and it is hardly reported that the high energy level dynamic compaction combined with humidification operation to collapsible loess was carried out.Therefore,Contrast testing study on 15000 kN·m high energy level dynamic compaction to collapsible loess with 15 000 kN·m high energy level dynamic compaction with humidification operation in the arid region in Northwest China was performed based on the large oil storage tank projects constructed by the country on Collapsible Loess.And a suitable construction process on high energy level dynamic compaction combined with humidification operation in the northwest arid collapsible loess area will be hoped to probed. Research conclusions: The results by testing study showed that the collapsible depth to be eliminated under 15 000 kN·m high energy level dynamic compaction to collapsible loess directly and 15 000 kN·m high energy level dynamic compaction combined with humidification operation was separately up to 10 m,15 m,its strength parameters were nearly 2 times more improvement.A suitable construction process on high energy level dynamic compaction combined with humidification operation in the northwest arid collapsible loess area was probed by this experimental study and it is a reference for similar ground treatment project.