凤滩大坝4号坝块坝基扬压力变化性态解析

基于凤滩大坝实测资料，对该坝4号坝块坝基扬压力的变化性态进行了定性分析，并结合逐步回归数学统计模型分析各环境量因子对坝基扬压力的影响程度，利用相关系数法和滞后模型分析扬压力滞后于库水位的滞后时间的变化，得出该坝块坝基地质性态的改变是引起扬压力异常的主要原因。文中所采用的相关系数法和滞后模型也可以应用到土石坝渗流分析、混凝土大坝各变形监测分析。

Analysis of Abnormal Uplift Pressure in No.4 Dam Block of Fengtan Dam

Based on observed data, this paper analyzes the abnormal uplift pressure in No. 4 dam block of Fengtan Dam qualitatively Then, by means of the stepwise regression mathematical statistic model, the influence of each environmental factor on the uplift pressure is analyzed. Finally, the lag time of uplift pressure behind the upper water level is analyzed by correlation coefficient method and lag effect model, and the results indicate that the change of geological condition of the foundation is the main cause of the abnormal uplift pressure. The correlation coefficient method and lag effect model adopted in the paper can also be applied to the analysis of seepage flow through embankment dams and deformation monitoring of concrete dams.