300 m级超高堆石坝心墙砾石土力学特性试验研究  

Experimental study on mechanical properties of core wall gravel soil of 300-m super high rockfill dam

作　　者：孟敏强 杨星 余挺 金伟 刘汉龙[2,4] MENG MinQiang;YANG Xing;YU Ting;JIN Wei;LIU HanLong(College of Water Resources and Architectural Engineering,Northwest A&F Universit,Yangling 712100,China;Key Laboraoyof New Technoogyfor Construction of Cities in Mountain Area,Chongqing University,Chongqing 400045,China;Power China Chengdu Engineering Corporation Limied,Chengdu 610072,China;School of Civil Engineering,Chongqing University,Chongqing 400045,China)

机构地区：[1]西北农林科技大学水利与建筑工程学院,杨凌712100 [2]重庆大学山地城镇建设与新技术教育部重点实验室,重庆400045 [3]中国电建集团成都勘测设计研究院有限公司,成都610072 [4]重庆大学土木工程学院,重庆400045

出　　处：《中国科学：技术科学》2023年第11期1834-1846,共13页Scientia Sinica(Technologica)

基　　金：国家自然科学基金优秀青年基金项目(批准号:51922024);国家自然科学基金青年基金项目(批准号:52108343);中国博士后面上项目(编号:2021M702689);山地城镇建设与新技术教育部重点实验室开放基金项目(编号:LNTCCMA-20210105);重庆市自然科学基金(杰出青年基金)项目(编号:cstc2019jcyjjqX0014)资助。

摘　　要：坝体的变形协调控制一直是高堆石坝设计和施工中的核心问题之一.对于300 m级超高堆石坝,由于国内外设计和施工经验较少,且用于300 m级超高堆石坝心墙防渗料的砾石土与一般砾石土力学特性存在较大差异,已有的研究成果尚不能有效指导工程实践.基于此,本文以两河口超高堆石坝心墙砾石土为研究对象,结合室内试验和现场试验结果,研究300 m级超高堆石坝心墙砾石土相关力学特性.结果表明,两河口超高堆石坝心墙砾石土具有较高压实度,其自身抗渗性能较好,可满足工程设计技术要求;通过压缩系数及压缩模量可知,所研究的心墙砾石土为低压缩性土;心墙砾石土峰值强度随围压的增大而增大,峰值摩擦角随围压的增大而减小,所得到的邓肯模型参数可为后续两河口超高堆石坝数值计算提供参考;现场试验表明两河口超高堆石坝心墙砾石土具有较高的承载力和抗剪强度,其渗透系数满足设计技术要求.本文通过相关室内试验及现场试验验证了砾石土作为300 m级超高堆石坝心墙防渗料的可行性及可靠性,研究成果可为300 m级超高堆石坝设计和工程建设提供相关试验及理论依据.The coordinated deformation control of dams has always been one of the key issues in the design and construction of high rockfill dams.Design and construction experiences for 300-m super high rockfill dams are limited both at home and abroad.The mechanical properties of gravel soil used as core wall impermeable material of 300-m super high rockfill dams are different from the general gravel soils.Existing studies cannot guide the engineering practice effectively.This study conducted laboratory and field tests on the core wall gravel soils of the Lianghekou super high rockfill dam to study relevant mechanical characteristics of core wall gravel soil of 300-m super high rockfill dams.The results show that the core wall gravel soils of the Lianghekou super high rockfill dam have a high compaction degree and good impermeability,which can satisfy the technical requirements of engineering design.The core wall gravel soil being studied has low compressibility according to the compression coefficient and compression modulus.The peak strength of core wall gravel soil increases with an increase in the confining pressure,and the peak friction angle decreases with increasing confining pressure.The obtained parameters of the Duncan model can serve as a reference for the numerical analysis of the Lianghekou super high rockfill dam.The field test results also show that the core wall gravel soil of the Lianghekou super high rockfill dam has a higher bearing capacity and shearing strength.Its permeability coefficient meets technical design requirements.This study verifies the feasibility and reliability of gravel soil as an impermeable material for the core wall of 300-m super high rockfill dams through laboratory and field tests.This study's findings can provide a relevant experimental and theoretical basis for the design and engineering construction of 300-m super high rockfill dams.

关 键 词：超高堆石坝 心墙砾石土 渗透 压缩 强度 试验研究 

分 类 号：TU4[建筑科学—土工工程]