三峡大坝水平位移回归监测建模分析

Regression Modeling for the Monitoring of Horizontal Displacement of Three Gorges Dam

利用三峡大坝顺河向水平位移及坝体测温监测资料,建立坝顶水平位移回归模型.模型回归系数显著性高,预测效果好.从回归模型定量分析可知,坝顶顺流向水平位移主要影响因素为库水位,其位移值占总量80％～90％,次之为坝体温度值,约占总量10％ ～ 18％.通过几年水平位移监测,大坝变形状态正常,监测数值在设计范围内,与水力荷载有很好的线性关系,温度影响与建筑物结构相对符合力学物理规律.时效位移值很小,说明坝体及基础相当稳定,没有大的不可逆变位.通过对因子的选取和相关分析,取用坝体代表性部位温度值来作为温度因子是可行和方便的选择,这为后期监测管理和后续砼结构设计提供参考性的范例.

A regression model of dam crest＇ s horizontal displacement was established using the monitoring data of horizontal displacement （along the river flow direction） and temperature of the Three Gorges Dam.The model prediction result is very good with highly significant regression coefficients.Through quantitative analysis,it＇s found that dam crest＇ s horizontal displacement in the flow direction is mainly affected by reservoir water level,making up 80％-90％ of the entire displacement; and temperature of the dam body is the second largest influencing factor,accounting for 10％-18％.Years of displacement monitoring data shows that the deformation of the dam is normal within the design range,in a good linear relationship with hydraulic load.The relation between temperature and dam structure conforms well with physical mechanics laws.Displacement caused by ageing is very small,which reveals that the dam body and foundation are quite stable,with no irreversible deformation.It＇s also found that taking the temperature at dam＇ s typical parts as the temperature factor is feasible and convenient.The research provides reference for following monitoring management and concrete structure design.