瀑布沟堆石坝砾石土心墙施工期孔隙水压力特征与分析  

CHARACTERISTICS AND ANALYSIS OF PORE WATER PRESSURES IN GRAVELLY SOIL COREWALL OF PUBUGOU ROCKFILL DAM DURING CONSTRUCTION PERIOD

作　　者：郑俊[1] 邓建辉[1] 杨晓娟[1] 陈向浩[1] 吕洪旭[1] 黄秋香[1] 

机构地区：[1]四川大学水力学与山区河流开发保护国家重点实验室,四川成都610065

出　　处：《岩石力学与工程学报》2011年第4期709-717,共9页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家重点基础研究发展规划(973)项目(2010CB226802;2010CB732005);国家自然科学基金资助项目(51079093)

摘　　要：土石坝施工期孔隙水压力长消过程十分复杂,以瀑布沟心墙监测资料为基础,分析施工期砾石土心墙的孔隙水压力特征及其形成机制,并与小浪底坝和鲁布革坝监测资料进行对比分析。研究结果表明:瀑布沟心墙施工期孔隙水压力长消主要有4种模式,即滞后响应型、即时响应型I、即时响应型II、不响应型;即时响应型II是最主要的长消模式;渗压计响应滞后的实质是渗压计周围土料从非饱和状态过渡到饱和状态的过程;渗透系数是影响渗压计是否滞后的决定性因素;即时响应型I长消模式是心墙局部含水量偏高的结果,施工过程中应尽量使心墙含水量均匀,避免产生即时响应型I长消模式;填筑速率对滞后响应型和即时响应型II孔隙水压力的长消影响显著,而对即时响应型I孔隙水压力长消影响不显著。因此,设计和研究砾石土心墙坝应高度重视砾石土的不均质性。The growth and dissipation process of pore water pressure in rockfill dams during construction period is very complex.Based on the monitoring data of Pubugou corewall,the characteristics and forming mechanism of pore water pressure during the construction period are analyzed.In addition,the comparative analyses between Pubugou dam,Xiaolangdi dam and Lubuge dam are made.The results show that：（1） The growth and dissipation modes of pore water pressure in Pubugou corewall during the construction period contain four modes which are delay-response mode,immediate-response mode I,immediate-response mode II and no-response mode.（2） The immediate-response mode II is the main growth and dissipation mode.（3） The essence of delayed response of piezometers is the process that the soil around the piezometers changes from nonsaturated state to saturated state.（4） The permeability coefficient of soil is the determinant factor of the delay response of piezometers.（5） The immediate-response mode I is the result of the more high water content in local corewall;so,in order to avoid the immediate-response mode I,the water content of corewall should keep uniformity during the construction period.（6） Filling rate has significant effects on pore water pressure of the delay-response mode and immediate-response mode II;and the effect on the immediate-response mode I is not obvious.The heterogeneity of gravelly soil should be paid high attention during the design and research stages of rockfill dams of gravelly soil corewall.

关 键 词：土力学 孔隙水压力 长消模式 砾石土心墙 不均质性 施工期 监测 

分 类 号：TU43[建筑科学—岩土工程]