清江隔河岩大坝1998年变形分析

Deformation analysis about Geheyan Dam on Qingjiang in 1998

:1998年 8月 8日 ,清江流域超过了千年一遇的洪水标准 ,隔河岩大坝蓄水位高达 2 0 3 .94m,超出正常蓄水位3 .94m,对长江下游防洪渡汛起了巨大的作用。在进行隔河岩大坝 1998年变形监测资料分析中 ,选择 3条横线 (坝顶 2 0 6m高程、坝体 14 5 m高程和坝基 ) ,4条竖线 (右拱座 # 10坝段、拱冠# 15坝段、左拱座 # 2 1坝段和重力墩# 2 6坝段 )的分析路径 ,采用物理推断法对变形量大的测点作了特征值分析 ;针对呈多峰曲线型的监测数据 ,采用广义线性多项式逐步回归方法建立了变形模型 ;最后对大坝工作状况作出初步分析。

On August 8,1998,the discharge of Qingjiang drainage area was higher than that given by the standard of flood frequency 0.1%,then,the water level before Geheyan dam was 203.94m,i.e. 3.94m higher than normal water level,so the storage of flood volume played a great role in the flood prevention downstream of Yangtze River.In the analysis of deformation monitoring data in 1998,taking three transveral lines(through dam crest level 206m,dam body level 145m and dam foundation,respectively)and four vertical lines(through the right arch abutment of dam section No.10,the arch crown of dam section No.15 ,the left arch abutment of dam section No.21 and the gravity pier of dam section 26,respectively) as analytic paths,the analyses of characteristic values for the measured points of large deformation quantity were made using physical rational method;aiming at the monitoring data with the type of multi peak curves ,a deformation model was established using step by step regression method,which contains general linear polynomial expressions;at last ,a preliminary analysis on dam working status was done.