通过分析当前大坝安全监测系统存在的问题,指出了基于SaaS(软件即服务)的大坝安全在线监控系统建设的必要性.在需求分析基础上进行了系统功能设计及研发,系统在多座水电站进行了推广应用,开创了基于工程安全大数据的服务新模式,提升了水库大坝安全管理水平.
随着信息化技术发展,传统纸质方式的水工巡视检查工作逐渐转变为巡检管理系统(模块).目前巡检系统仍存在巡检对象未抽象分类、缺陷未对象化、巡检App功能简单等问题.针对以上问题提出优化设计方案,并应用于雅砻江流域大坝安全信息管理系统的巡检模块,主要包括Web端和移动端(App),具有查看任务、巡视检查、结果记录和查询、缺陷跟踪和查询等功能.本系统借助水工巡检信息化管理手段,优化现行流域大坝系统中有关水工巡检信息管理模式,能够进一步提升大坝安全管理信息化技术水平.
结合设计审查,系统梳理了小型水库安全监测设计存在的典型问题,包括部分设计单位能力不足、重要设计内容缺项漏项、设计相关的基础信息不全、已有安全监测设施利用不合理、设计未联系工程实际、监测项目本末倒置等.提出从高度重视设计工作、加强指导与培训、强化设计审查、特别关注除险加固与新建小型水库的安全监测设计等方面加强安全监测设计质量管理.
国内土石坝大多建于20世纪五六十年代,受当时技术、施工条件影响,许多水库存在大坝渗漏的安全隐患,或多或少需要防渗加固处理.以大连市驼山乡龙泉水库为例,探讨高压喷射灌浆在土石坝防渗中的应用.
以某病险水库溢洪道除险加固工程为例,分析了现状溢洪道存在的主要问题,复核了溢洪道宽顶堰泄流能力、泄槽段边墙高度、底板抗冲能力及边墙稳定性.根据实际存在的主要问题提出了具体的加固设计方案,为溢洪道的除险加固提供了技术依据,也为类似工程提供了经验参考.
防洪闸门的运行常受到流激振动的影响,尽管对特定闸门类型的物理特性有所了解,但要判断非预期条件下闸门的动态行为仍然具有挑战性.笔者提出了一种混合建模系统,将机器学习与基于物理的建模相结合以预测振动,从而应对可能出现的紧急情况.闸门响应数据由传感器获取并存储在数据库中,对于淹没流条件下的闸门,根据闸门开度和折合流速划分安全和不安全情况.利用基于流固耦合的有限元模型向系统数据库提供补充数据.该系统为闸门控制和防洪管理提供了安全有效的参考建议.
某抽水蓄能电站下水库面板及趾板混凝土施工期出现了较多裂缝,裂缝以深层缝、渗水缝为主,裂缝长度1.1～13.2 m,裂缝宽度0.03～1.12 mm,其中面板裂缝基本为规则横向,趾板裂缝垂直于趾板延伸方向,有极少数斜向裂缝、X型裂缝、Y型裂缝,初步分析裂缝的产生主要与混凝土干燥收缩、温度变形、基础约束等因素有关.针对Ⅰ～Ⅳ类不同类型的裂缝,分别采用了表面封闭、封缝无损贴嘴+表面封闭、切线槽化学灌浆+表面封闭、凿槽封缝后化学灌浆+表面封闭等不同方法进行处理.蓄水前压水试验检查结果表明,裂缝处理效果良好,缝内填充密实,裂缝隐患得到有效消除.蓄水运行后未见明显渗漏,下水库运行状况稳定.
台风对我国的大坝运行安全存在巨大的影响,尤其对东南沿海一带台风频发区域的大坝.台风对大坝的影响程度主要由风力等级决定.目前中国气象局已实现台风路径和台风四个象限不同风力等级半径预报.建立关注大坝的地理坐标信息库,实时获取台风预报信息,计算台风未来不同风力等级的影响范围,依据关注大坝所处风力等级影响范围,实现分级预警.通过计算机编程实现上述功能,快速找到可能遭受台风破坏的大坝,为大坝遭遇台风实现快速预警.
运营期间,水工建筑物缺陷在复杂水环境下逐渐暴露,尤其是门槽二期混凝土,其缺陷修复处理影响了电站运营收益和电站及下游建筑物的安全,国内外对运营期非泄水水下修复施工的成功案例较少.以湖南修山水电站拦污栅门槽二期混凝土为例,通过拦污栅闸门反力架,形成模板支撑体系,根据不同槽深灌注细石自密实水下不扩散混凝土和采用水下环氧砂浆批荡方法,对发电期水下门槽二期混凝土进行了修复.该技术还成功推广应用于湖南安江水电站进口门槽二期,可为其他类似项目提供借鉴.
The construction methods of Yangtze river water intake project in Wuwei City include pipe jacking, trenching, borehole grouting pile and so on. The project has changed the water level and velocity conditions in nearby area, which has a certain adverse impact on the embankment seepage and stability of bank slope, but has no adverse impact on the overall and local stability of river regimes. In this regard, measures for embankment reinforcement, bank slope protection and foundation seepage prevention are put forward, and reasonable suggestions are put forward to further reduce the impact of flood.
Taking the emergency disposal of large-volume floating objects in Gaobazhou reservoir of Hubei province as an example, this paper introduces the event process and risk analysis of Gaobazhou hydropower station facing the accumulation of floating objects such as large-scale fish farming cages in the reservoir due to heavy rainfall in the Qingjiang river basin. As well, the effective practice of flotsam cleanup and emergency disposal of Qingjiang Company of China Three Gorges Corporation is summarized, for reference.
The formation and expansion of plastic relaxed zone is a hot issue in the research of surrounding rock stability of underground engineering. Combining elastic-plastic theory, engineering geophysical prospecting and monitoring data, the stress state and the deformation and failure characteristics of surrounding rock in plastic zone of large underground cavern are discussed, and the estimation method for plastic relaxed zone based on monitoring results from multi-point displacement meters is proposed. The results show that the distribution of deformation along the hole depth mainly accumulates in plastic zone. The depth and displacement of boundary points of plastic relaxed zone can be estimated by the hole depth-displacement curve. The estimation results are basically consistent with the calculation results of elastic-plastic theory, indicating that this study has certain reference value.
At present, it is difficult to record monitoring data when sluice are opened for flood discharge,especially in the case of dam deformation, the safety will be affected. Therefore, in order to understand the stability state of dam safety, a deformation monitoring system for reservoir dams based on 3D laser scanning is proposed. The working principle and equipment functions of the deformation monitoring system are introduced. The point-to-surface deformation comparison analysis mode is used to monitor dam deformation, and the source program is developed to realize the processing, comparative analysis and modeling of the integrated monitoring point cloud data. The intelligent machine system is applied to the actual monitoring of dam deformation. The results show that the system meets the design requirements in terms of stability, reliability, real-time and accuracy, resulting in higher data integrity rate.
Reasonable demonstration of impact from dam-break flood is of great significance to dam risk assessment and emergency management. When it comes to cascade dams failure, a 1D and 2D hydraulic coupling model is established to analyze the propagation of dam failure flood and the inundation of floodplain downstream the dam. Taking cascade hydropower stations on W river as an example, the impact of dam failure under two reservoir operation conditions in flood season and non-flood season, is considered in the model. The propagation of dam break flood is analyzed from aspects such as the peak discharge, maximum water level and timing of flood on typical section. On this basis, taking the maximum inundated depth of the flood plain as a representative index, dam failure flood risk level is divided and the flood risk map is drawn. The areas with high risk in case 1 and case 2 are 431.31 km~2 and575.76 km~2 respectively, indicating the great impact of dam break flood on downstream areas. The simulation results have important reference value for developing emergency plans as well as disaster prevention and mitigation.
The buried penstock with high head and large HD in Shisanling pumped storage power station has been in operation for more than twenty years, and the operation environment is complex, with high risk during filling and draining period. The analysis of the penstock filling and draining in 2017and 2018 was carried out. By reviewing the parameters related to the emptying condition, the monitoring data of structural stress and external water pressure during the operation period and the filling and draining period was analyzed. The comprehensive evaluation results showed that the penstock structure was in good operating condition.
During the debugging and operation of relay hydraulic hoist in Shuikou hydropower station,the automatic opening and closing action broke down. The reason may be that the unexpected opening of hydraulic single-direction valve with pressure pre-release function causes the pressure unloading of rodless cavity of no-load cylinder. The pressure drop at electro-hydraulic directional control valve port and oil return filter is calculated to obtain the pressure value at the control port of hydraulic single-direction valve. Base on analysis of the force on the hydraulic single-direction valve core, it is confirmed that the hydraulic single-direction valve would open in reverse direction. The solution is to reinstall the hydraulic single-direction valve without pressure pre-release under low pressure working condition.
From the point of view of responsibilities, interpretation of Regulation for Hydropower Dam Safety Emergency Management is performed through three aspects, namely the subject responsibility of dam safety emergency management, government-enterprise collaboration and information sharing as well as supervision and management responsibility, for reference.
2022年11月,国家能源局印发了《水电站大坝运行安全应急管理办法》(以下简称《办法》),这是《水电站大坝运行安全监督管理规定》(国家发改委23号令)最新配套规范性文件.《办法》的发布实施,标志着覆盖水电站大坝运行安全管理全过程的法规体系基本完备,形成了常态化监督管理和非常态化应急管理相衔接的水电站大坝运行安全监督管理机制.
