土石坝砾石土心墙孔隙水压力变化分析  

Analysis of the Change of Pore Water Pressure in Gravel Soil Core of Rockfill Dam

作　　者：耿瑜平[1] 蓝树猛[1] 

机构地区：[1]黄河勘测规划设计有限公司,河南郑州450003

出　　处：《人民黄河》2016年第1期98-101,共4页Yellow River

摘　　要：土石坝心墙作为坝体主要防渗结构,在施工期产生的孔隙水压力幅度、消散水平及初蓄期的防渗性能对大坝的初蓄和运行安全有着重要的影响。对某高土石坝砾石土心墙孔隙水压力监测资料的分析表明,砾石土心墙在施工期产生的孔隙水压力幅度与上覆土压力、土体饱和状态和渗透系数有密切关系,孔隙水压力消散水平与库水位变化幅度关系不大,主要与材料特性相关。初蓄期由于心墙土体未完成固结,库水位快速抬升,心墙易加速沉降,从而降低土体强度产生水力劈裂,因此心墙土石坝在初蓄期应严格控制库水位抬升过程,加强心墙中部孔隙水压力及下游侧渗透水压力监测,这对确保大坝的安全具有重要意义。The core-wall is the main anti-seepage structure in rockflll dam. The amplitude and dissipation rate of the pore water pressure produced in construction period,and early storage period anti-seepage performance of core-wall have an important impact on the dam security in early storage and operation period. Based on the monitoring data of pore water pressure of gravel soil core-wall of a high rockfill dam,the analysis show that,there is a close relationship between the pore water pressure amplitude which is produced in the construction period and the soil pressure,soil saturation degree and coefficient of permeability,but there is little relationship between the changes of reservoir water level and dissipation of pore water pressure,which is mainly related to the material properties. In the early storage period,because the soil of core-wall does not complete the consolidation,fast uplift of reservoir water level will cause larger deformation speed of the core-wall,the reduction of soil strength and hydraulic fracturing. The control of the reservoir water level rising,enhancement of monitoring of the pore water pressure in the core-wall and the seepage water pressure at the downstream side of core-wall,have great significance to the dam security.

关 键 词：土石坝 心墙 孔隙水压力 消散 水力劈裂 

分 类 号：TV641.1[水利工程—水利水电工程]