压坡体对土石坝抗震性能的影响及地震安全性评价  

Influence of slope-compaction zone on rockfill dam seismic performance and earthquake safety evaluation

作　　者：邹德高[1,2] 屈永倩 高东红 杨智凯 刘京茂[1,2] 王辉 ZOU Degao;QU Yongqian;GAO Donghong;YANG Zhikai;LIU Jingmao;WANG Hui(State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China;School of Infrastructure Engineering,Dalian University of Technology,Dalian 116024,China;Shanghai Investigation Design&Research Institute Corporation Limited,Shanghai 200434,China)

机构地区：[1]大连理工大学海岸和近海工程国家重点实验室,辽宁大连116024 [2]大连理工大学建设工程学院,辽宁大连116024 [3]上海勘测设计研究院有限公司,上海200434

出　　处：《人民长江》2025年第3期164-171,共8页Yangtze River

基　　金：国家自然科学基金项目(52192674,52109151);水利部重大科技项目(SKS-2022101);西藏自治区重点研发计划项目(XZ202201ZY0017G)。

摘　　要：目前一大批抽水蓄能电站正在规划和建设,由于环保的要求,大量的弃渣料堆积在土石坝坝坡形成压坡体。由于缺少相应规范指导,压坡体普遍采用坝体标准进行抗震安全评价,经常导致强震区工程的压坡体难以满足要求而进行过度设计,丧失了经济性,研究强震下土石坝压坡体影响机制及评价方法具有重要意义。针对超强地震区的土石坝工程,考虑大坝-无限地基动力相互作用,开展了全弹塑性的动力强非线性变形分析以及等价线性动力分析和时程稳定分析,研究了压坡体对坝体地震反应的影响机制,提出了压坡体地震安全评价方法。结果表明:压坡体对坝坡的法向压力明显大于顺坡向剪切力,压坡体有利于减小坝体地震变形;压坡体孔隙率变化对坝体地震变形基本没有影响,无需提高压坡体碾压标准;压坡体抗滑稳定最小安全系数对应的是不影响坝体安全的浅层无害滑面,建议采用大坝整体变形或穿过坝体的有害滑面稳定性(安全系数及滑移量)进行压坡体地震安全评价。研究成果为强震区土石坝压坡体的抗震设计和安全评价提供了支撑。Numerous pumped storage power stations are currently in the planning and construction phases.Owing to environmental protection requirements,substantial waste slag accumulates on dam slopes of rockfill dams,forming slope-compaction zones as referred in below context.The absence of specific standards for this zone leads to the application of general dam body standards for assessing seismic safety,often resulting in over-design and economic inefficiency,particularly in regions prone to severe earthquakes.Therefore,it is of considerable engineering significance to investigate influence mechanisms and evaluation methodologies of the slope-compaction zone under strong seismic conditions.Considering dam-foundation interactions,analyses such as elastoplastic dynamic response,equivalent-linear analysis,and time history stability assessment are conducted for a rockfill dam located in an area susceptible to extremely strong earthquakes.The impact of the slope-compaction zone on the integrity of the dam is investigated,and a method for evaluating its seismic safety is proposed.Findings reveal that the normal pressure exerted by the slope-compaction zone on the dam′s slope significantly exceeds the shear forces along the slope,thereby aiding in reducing seismic deformation of the dam structure.Moreover,the porosity of the slope-compaction zone does not influence seismic deformation,suggesting that enhancements to construction standards in this zone are unnecessary.The minimal safety factor for the dynamic stability of the slope-compaction zone only refers to a superficial,non-threatening sliding surface that does not threaten the dam′s safety.It is recommended that either the overall deformation of the dam or the stability(safety factor and slip deformation)of critical sliding surfaces through the dam body be used to assess the seismic safety of the slope-compaction zone.The research provides support for the seismic design and safety evaluation of rockfill dams with a slope-compaction zone in areas prone to strong earthqu

关 键 词：土石坝 压坡体 地震响应 地震安全性评价 抽水蓄能电站 

分 类 号：TV641[水利工程—水利水电工程]