High excess static pore water pressure will rise in the core-wall of earth dam during the rolling construction period.For the high earth dam,the excess static pore water pressure produced in the core-wall of earth dam during construction can not be effectively dissipated,and the existing high pore water pressure will lead to the reduction of effective pressure in the core-wall,which influences the performance of core-wall and stability of the dam.Based on the monitoring data of a gravelly soil core-wall,the influences of core-wall filling building and reservoir storage on the pore water pressure formation and variation are analyzed.The calculation of pore water pressure dissipation in the core-wall is simplified to one-dimensional consolidation method of vertical compression and horizontal drainage,and it is applied to the calculation of pore water pressure dissipation in the core-wall under the condition that the core-wall filling building is completed and reservoir water level keeps constant. The reasonability of simplifying calculation is verified through the comparison of the tested and calculated data.It is found through the consolidation process of the core-wall that it will take 10 to 30 years when the degree of consolidation achieves 95%,and at each monitoring point achieves 70% at 10 years.%土石坝的碾压施工会在大坝心墙中产生较高的超静孔隙水压力.对高土石坝,施工期心墙内产生的超静孔隙水压力难以有效消散,使得心墙内长期存在较高的孔隙水压力,导致其有效应力降低,影响心墙的工作性态和大坝稳定性.以某砾石土心墙监测资料为基础,分析了心墙填筑及水库蓄水对孔隙水压力及其变化的影响.提出了一种计算堆石坝心墙孔隙水压力消散的简化方法,即竖向受压而水平排水的一维固结方法.将其应用于心墙填筑完成后库水位保持不变时段的心墙孔隙水压力消散计算,通过计算值与实测值的比较,验证了心墙孔隙水压力简化计算方法的合理性;并进一步计算了心墙测点的固结过程,发现其固结度达到95%所需的时间长达10~30 a,其中前10 a各测点的固结度均已达到了70%.
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