黄河黑山峡大柳树坝址与小观音坝址岩体质量差异的原因探讨

RESEARCH ON REASON OF ROCKMASS DIFFERENCE BETWEEN DALIUSHU AND XIAOGUANYIN DAM SITES ON HEISHAN GORGE OF YELLOW RIVER

黄河黑山峡大柳树坝址与小观音坝址相距仅48 km,两坝址岩性均为变质长石石英砂岩夹千枚岩。大量的勘察资料表明两坝址的岩体质量有明显差别,本文从两坝址岩体的波速、岩体质量分级、坝基岩体渗透性等几个方面进行对比,阐明了两坝址岩体质量的差别,并指出地震动力破坏是造成大柳树坝址形成大范围松动岩体的主要原因,因此也是两坝址岩体质量差异的主要原因。

The Daliushu dam site and the Xiaoguanyin dam site are both located on the Heishan Gorge of Yellow River. There is just a distance of 48 km between them. They also share rockmass of layers of metamorphosed feldspar-quartz-sandstone and phyllite. Large quantities of research and investigation materials show obvious difference between their rock mass quality. After contrast analysis on the rockmass wave velocity,grading of rockmass quality and permeability of dam base rockmass,the difference of rockmass quality between the two dam sites is analysed,and it is pointed out that the seism-dynamical damage is the primary cause for the formation of large scaled relaxed rockmass. Thus it is also the primary reason for rock mass difference of the two dam sites.