摘要
采用土工离心模拟技术研究4种不同土质的上覆土层在地下断裂时的性状反应,分别模拟基岩垂直位错与水平位错两种基岩断裂形式,其最大模拟位错量分别达4.5,3.0m,由此获得以下试验结果:(1)当基岩断裂位错时,张性的正断错位比水平错位对上部土层的开裂影响要大;(2)上部覆盖为单一的软–中等强度的土层比粗细相间沉积的土层影响要大;(3)当断裂位错1~3m时,土层开始出现裂缝,其破裂高度均在20m以内;当断裂位错增大到4.5m时,土层破裂向上发展,但均在30m以内。本文的分析与结论对于场地断裂工程抗震评价及有关规范的修订具有参考价值和指导意义。
By means of the geotechnical centrifuge technology, the four different overburden soils are studied by simulating vertical and horizontal faults, whose maximum bedrock offsets are 4.5 and 3.3 m, respectively. The results show that: (1) when bedrock fracture occurs, the influence range inside overburden soils produced by vertical fault (down fault) is greater than that produced by horizontal fault (strike slip fault); (2) the influence degree inside single middle strength soft soil is greater than that inside the cross bedding's sedimentary soils composed of coarse and fine grained soil layers; and (3) under way of bedrock offset 1-3 m, the fracture inside overburden soils appears and all fracture heights are less than 20 m. When the bedrock offset becomes great enough to 4.5 m, the fracture expands inside overburden soils but the fracture heights are all within 30 m. It shows that the centrifuge test results have significant references to both the evaluation of countermeasure against faults in engineering practice and the revisions of some design regulations.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2005年第11期1868-1874,共7页
Chinese Journal of Rock Mechanics and Engineering