【作者】 高笑娟； 李达； 雷居强；

【Author】 GAO Xiaojuan;LI Da;LEI Juqiang;School of Civil Engineering,Henan University of Science and Technology;

【机构】 河南科技大学土木工程学院；

【摘要】 通过对洛阳市轨道交通1号线史家湾站在基坑开挖施工前的抽水试验,在土层中埋入分层沉降观测点,测试水位下降时土层沉降值,与经验公式计算沉降值进行对比分析。测试结果表明:卵石层中土层沉降随着水位下降基本上呈线性增大,滞后性表现不明显;由于卵石层的压缩模量大,土层的沉降量较小,在预定的降水深度下,沉降值不会对管线造成不利影响,但是对于级配不良存在管涌条件的卵石层,土中细颗粒流失造成的空洞和坍塌现象可能会对管线及周围建筑造成不利影响;利用经验公式计算所得的沉降值与实测值比较接近,可以用于基坑开挖前降水引起的沉降量的预估。更多还原

【Abstract】 The deformation law of stratified settlement was studied through the stratified settlement points set in the soil in subway station in rail transit based on the pumping test.Settlement calculation values with experience formula are compared with the measure values.The results show that the soil settlement changes linear with the water level without hysteresis.Because of the high modulus of compression of boulder bed,the settlement value is very small and has little effect on the pipes around foundation ditch under predicted precipitation depth.But the piping phenomenon must be attracted attention with the construction dewatering process.The fine grained soil between the coarse-grained soil may be carried off with the construction dewatering process.The voids in the soil may lead to soil collapse and effect on the normal use of buildings and pipelines near the foundation pit.The stratified settlement of the calculated value is close to the measured value and the theoretical calculation method may be used to prediction the settlement of dewatering.更多还原