落石冲击下电力构筑物的破坏机理及防护措施研究

As the western China has relatively dense water power, many huge hydroelectric power stations are set in that region. The construction of those power stations should be adjusted to the particular terrain like mountain or canyon. Usually, the transformer substations as well as switching stations, which used for power transmission, are located next to the powerhouse at the foot of mountains. Thus, these buildings are especially vulnerable to the rockfall, which is both an unavoidable and challenging scientific problem. Rockfall impact is a collision problem about dynamic contact, which is crucial in many technology realms without convenient solutions. A common analytical model has not been established yet. This issue mainly depends on the theoretical and experimental analysis; also practical research project will be included. One aim of this issue is adopting engineering measures to prevent electrical equipments from being damaged by rockfall. The mechanism of rockfall impact will be discussed, as well as the variation of buffering effect of the cushions among different kinds of surface materials is investigated. Besides, a comprehensive assessment on the performance of the power structure against rockfall impact will be included. Based on the function of the studied structure, a new structural system is proposed, which possess the multiple protection features, good impact resistance and overall firm performance. Propose a dynamic analysis model anastomose the characteristic of the studied structure suffered rockfall impact, in addition the theory of assessment and methods concerning the vibration effect about the electrical equipment are presented. Ultimately, provide a scientific reference for the design both on the special structures of the rockfall impact and the control of vibration.

在水力资源相对集中的西部地区，大型水电站要充分利用高山峡谷地形兴建，电力输出的变电站、开关站往往只能建在紧邻水电站厂房的山脚下，落石对其构成了严重的威胁，考虑落石冲击影响是不可回避且富有挑战性的科学问题。落石冲击是一个动力接触的碰撞问题。动力接触的碰撞问题在许多技术领域既十分重要又难于求解，到目前为止，研究者尚未建立通用的分析模型。本课题拟采用理论分析与试验研究为主，再结合实际工程调查的研究方法。考虑以工程措施防护落石对电气设备的危害。对落石的冲击作用机理进行研究，探讨不同表面垫层材料的缓冲效果；全面评估电力构筑物抗落石冲击的性能；针对所研究结构使用功能，提出具有多重防护功能、良好抗冲击及整体牢固性能的结构体系。提出符合研究结构特点的落石冲击下动力分析模型及对电力设施振动影响的评估理论及方法。为防护落石的构筑物的抗冲击设计及减振控制设计提供科学依据。

崩塌滚石灾害是我国山区常见的一种自然地质灾害，对其危害范围内的公路、桥梁、隧道、电力构筑物等及人类活动造成严重的威胁。滚石灾害具有突发性、随机性、速度快、能量高、影响范围大、危害严重、监测预警及防治困难等特点。“5.12”汶川大地震后，滚石灾害活动性明显增强，而我国滚石灾害基础基础研究十分薄弱，开展落石冲击试验研究十分必要和紧迫。传统棚洞结构是在钢筋混凝土棚洞板上覆盖一定厚度的砂砾石垫层，吸收滚石冲击能量以减轻冲击荷载对防护结构的冲击力。然而，传统棚洞在设计上存在以下的缺陷：其一，顶部覆盖砂砾石垫层自重较大，下部基础需要设计较大体量，极大增加了工程投资；其二，对于落石的清理和垫层的修复、更换都较为困难。本课题组在上述情况下，开展了以下几方面研究：（一）大量搜集整理国内外关于落石冲击防护工程方面的研究成果，避免闭门造车。（二）采用有限元法、离散元法等数值仿真模拟手段进行理论分析，为后续试验工作的开展提供一定参考。（三）落石冲击试验研究。（1）在室外搭建落石冲击试验平台；（2）开展不同落石冲击能量情况下，钢筋混凝土棚洞板的破坏机理试验研究，探讨落石与承灾体的动力相互作用机理，探索冲击能量对承灾体变形破坏的定量影响；（3）开展不同落石冲击能量情况下，各类外墙保温材料垫层（如：岩棉、PEF板、玻璃棉板、硅酸铝板、EPS板、XPS板等等）的缓冲效果试验研究。（4）设计研发新型落石冲击防护装置。其中设计了S型钢和彩钢板组合垫层、Ω型钢筋缓冲装置、U型钢带缓冲装置、新型PVC-U管缓冲支座。（5）借鉴终点弹道学领域成果，设计并研究了芳纶纤维布、碳纤维布、大理石瓷砖分别作为钢筋混凝土板抗冲击背板材料及面板材料的防护效果。（6）开展砂砾石垫层和土垫层及废旧轮胎组合情况下，钢筋混凝土棚洞板的缓冲效果试验研究。综上所述，希望本课题组研究成果能为滚石防护工程提供一些借鉴参考。