漳泽水库坝体沉陷与裂缝的产生及原因分析

Analysis of Causes on Settlement and Crack of the Dam Body of Zhangze Reservoir

漳泽水库泄水洞改建施工中,消力池基坑发生管涌,于1990 年7 月30 日中午发现坝体沉陷与裂缝。沉陷长70m ,0 +760 断面沉陷量最大。坝顶为509m m ,防浪墙为1 875m m(8 月到12 月)。共发现裂缝18 条,总长89-9m ,单缝最长6-8m ,最深2-2m ,最大缝宽1-5m m 。经分析认为产生沉陷与裂缝的主要原因有(1) 坝体质量差;(2) 消力池施工中基坑长期排水;(3)坝基沙层与轻亚粘土在管涌时被冲走,地基陶空,上部沉陷;(4) 施工期间长期通行载重汽车,振动碾碾压坝等,其中以(2)、(3)

When the reconstruction of sluice tunnel of Zhangze Reservoir was being carried on,piping occurred in its foundation pit of stilling basin,the settlement and cracks occurred then in dam body in the noon of July,30 th ,1990.The scope of settlement is 70m in length,the maximum settlement in dam top and wave wall are 1 509mm and 1 875mm(from August to December)respectively.The number of cracks is 18,total length being 89 9m.Of the single crack,the maximum length is 6 8m,maximum depth is 2 2m,and maximum width being 1 5mm.The result of analysis shows that the causes of the settlement and cracks are: (1)poor quality of dam body,(2)Long-time drainage in foundation pit in course of the reconstruction of stilling basin;(3)sand layer and loam layer under the dam are scoured by piping,and dam foundation is caved,and (4)the other causes.