加筋褥垫层在灰土挤密桩复合地基中的应用

Study on Reinforced Cushion in Lime Soil Compaction Pile Composite Foundation

通过对建筑条形地基下的灰土挤密桩复合地基加筋褥垫层的现场试验,对桩顶、桩间土应力、三向土工格栅应变等项目进行了测试,得到了在桩土应力比、三向土工格栅应变随建设高度的变化过程线。通过现场试验表明,建筑条形地基下加筋褥垫层灰土挤密桩复合地基中,在不同位置桩顶应力、桩间土应力有不同的变化趋势;桩间土的变化趋势也有不同,在柱下、条形基础交接处中心达到最大值。通过柔性位移计对土工格栅的变形进行量测,得到土工格栅在纵向、横向、斜向的应变变化过程线,试验表明:不同位置的土工格栅的应变变化过程线差异较大,在柱下、条形基础交接处中心达到最大值。同一位置的3个不同方向应变变化过程线也有差异,柱下条形基础交接中心处斜向肋条受力最大。

Through the field test in the construction of lime soil foundation with compaction pile composite foundation reinforced cushion,the stress on top of the pile and on the soil between the piles and the strain of the triaxial geogrids were tested,and the variation curves of pile-soil stress ratio and the strain of triaxial geogrid with construction height were obtained.It is shown that in the composite foundation with reinforced cushion and lime soil compaction pile under the strip foundation,the stress at the top of the pile and the soil stress between the piles vary in different positions;the variation trend for the soil between piles is different also,and the maximum value is reached at the center of the transition between the column and the strip foundation.With flexible displacement meter the deformation of geogrid was measured in terms of geogrid strain in the longitudinal,transverse and inclined process line.The test showed that the strain variation in different position of the geogrid is different,and reaches the maximum in the column and the center bar based handover.In the same position,the three different directions of strain change process lines are also different,and the maximum stress is at the center of the transfer column strip foundation under oblique ribs.