超高土石坝砾石土互层厚度动态调整工艺研究  

Study on dynamic adjustment process of gravel-soil interbedding thickness in ultra-high earth-rock dam

作　　者：张海龙 乔介平 方德扬 邱银宝 ZHANG Hailong;QIAO Jieping;FANG Deyang;QIU Yinbao(Yalong River Hydropower Development Co.,Ltd,Chengdu 610056,China)

机构地区：[1]雅砻江流域水电开发有限公司,四川成都610056

出　　处：《人民长江》2021年第2期132-136,共5页Yangtze River

摘　　要：超高土石坝常采用砾石土心墙结构以增强防渗体协调变形能力,砾石土互层厚度是决定砾石土砾石含量的重要指标。常规方法未考虑料源砾石含量差异的影响,砾石含量控制精度较低。基于砾石含量守恒原理,推导出砾石土互层厚度动态调整公式。以两河口水电站工程为例,通过对比试验论证了利用动态调整法确定砾石土互层厚度较常规方法更为精确。为减小动态调整法中因试验检测频次增加对工程的制约,基于敏感性分析原理,确定了料源砾石含量允许波动范围,并利用料场复勘、料源开采前检测、开采过程中由土料前层检测数据确定后层土料铺料厚度等手段,加强工序衔接。充分考虑冬雨季因素,灵活调整砾石土互层施工先后顺序,最大限度保障砾石土质量。相关方法及结论对工程施工具有一定的指导意义。Gravel-soil core wall structure is often used in ultra-high earth-rock dams to enhance the ability of coordinate deformation of seepage control body,and the gravel-soil interbedding thickness is an important index to determine gravel content of gravel-soil.In the conventional method,the difference of gravel content is not considered,which may lead to the low accuracy of gravel content control.In this paper,the formula of dynamic adjustment process of gravel-soil interbedding thickness was proposed by the conservation principle of gravel content,and it was verified that the dynamic adjustment method was more accurate than the conventional method by the comparative test of Lianghekou Hydropower Station.In order to reduce the restriction on the project progress caused by the increase of test frequency in the dynamic adjustment method,the allowable fluctuation range of gravel content was determined based on the sensitivity analysis principle,and the measures of re-exploration of material yard,pre-mining detection,and thickness of new layer being determined by detection data of pre-layer were used to strengthen the process connection.Finally,considering the factors of winter and rainy season,the construction sequence of gravel-soil interbedding can be adjusted flexibly to ensure the quality of gravel-soil.

关 键 词：砾石土心墙 砾石土互层厚度 砾石含量 敏感性分析 两河口水电站 

分 类 号：TV5[水利工程—水利水电工程]