微型注浆钢管桩在高铁站场软基加固中的应用研究

对新建鲁南高铁站场软土地基采用微型注浆钢管桩进行加固,探讨了软土地基微型注浆钢管桩加固方案及其施工技术;为评价站场软基微型注浆钢管桩加固效果,开展微型注浆钢管桩成桩施工过程中现场监测试验,通过埋设监测元件获得加固区邻近区域土体的变形分布与发展规律。结果表明在微型注浆钢管桩成桩过程中,地表纵向水平位移变化比较小,地表竖向位移无明显变化,产生的深层横向水平位移和纵向水平位移都较小;并且在成桩过程中,各测试断面的孔隙水压力随地下水位的下降而略有降低,没有出现明显的超孔隙水压力。这些结论证明采用微型注浆钢管桩加固站场软基是成功的,可以进一步推广使用。

Application Research of Micro Grouting Steel Pipe Pile in Soft Foundation Treatment of High-speed Railway Station

The soft soil foundation of newly-built Lunan high-speed railway station is reinforced by micro grouting steel pipe pile.The reinforcement scheme and construction technology were discussed.Field monitoring test was carried out in order to evaluate the reinforcement effect of micro grouting steel pipe pile on soft foundation of station yard.The deformation distribution and development rules of the soil near the reinforcement area were obtained by embedding monitoring elements.The results show that under micro grouting steel pipe pile forming,the change of longitudinal horizontal displacement of the surface is relatively small,the surface vertical displacement has no obvious change,and the deep horizontal displacement and longitudinal horizontal displacement are small.And in the process of pile forming,owing to the decrease of groundwater level,the pore water pressure of each test section slightly decreases,and excess pore water pressure does not appear.These conclusions prove that it is successful to use micro grouting steel pipe pile to reinforce station soft foundation,and it can be further promoted to use micro grouting steel pipe pile to reinforce soft foundation.