强震动条件下的水电站大坝反应特征研究

发布时间：2018-08-24 17:55

【摘要】：我国水力资源十分丰富,水力发电是我国重要的电力资源之一,但我国也是一个地震多发的国家,尤其是水电资源丰富的西南地区,地震活动非常频繁,水电工程基本都处在地震高烈度区。水电站大坝是水电工程的1级建筑物,具有重要的功能和非常高的安全要求,为此,国家能源局规定已建成大型水电工程应进行大坝强震动监测。强震动监测是大坝监测的重要内容,通过在大坝等水工建筑物和场地布置监测地震活动的台阵,记录强震时建筑物监测部位和场地的地震反应信息,进而评估大坝在强地震过程中的安全性。论文以董箐水电站面板堆石坝为研究对象,以强震动监测数据为基础,采用Seismosignal软件对291条样本数据进行波形错点剔除、基线校正、滤波去噪等预处理和数值积分、频谱分析等常规处理,得到每个样本的加速度峰值和振幅谱峰值,分析研究了不同震源方位和不同震级强度下大坝主要监测点的反应规律;同时分析了大坝不同部位监测点的反应规律,结论如下:(1)震源方位反应特点:震源在右岸时,左坝肩、坝腰、坝脚地震反应基本一致,震源在左岸时,左坝肩较坝腰、坝脚反应明显。(2)不同震源和震级条件下,坝顶中部的地震反应最强,同时,地震反应随高程呈现放大效应。(3)对各监测点各分量研究表明南北向分量(本文近似顺河向)参数较其它分量大,说明库水的动荷载作用对其影响较大。(4)大坝不同位置的地震反应特征除与监测位置、高程有关外,震级和震中距是主要影响因素,震源与大坝的方位关系也会产生重要影响。(5)大坝强震动特征的研究成果可为大坝抗震设计、日常安全观测提供参考资料。
[Abstract]:China is rich in hydropower resources and hydropower is one of the important power resources in China. However, China is also a country prone to earthquakes, especially in the southwest of China, where hydropower resources are abundant, and seismic activities are very frequent. Hydropower projects are basically in high seismic intensity areas. The hydropower dam is the first grade building of hydropower project, which has important function and very high safety requirement. Therefore, the State Energy Bureau stipulates that the dam strong vibration monitoring should be carried out in the large hydropower project. Strong motion monitoring is an important part of dam monitoring. Seismic response information of monitoring site and site of buildings during strong earthquakes is recorded by arranging seismic array in hydraulic structures and sites such as dams. Then the safety of the dam during strong earthquakes is evaluated. Taking Dongqing concrete face rockfill dam as the research object, based on the strong vibration monitoring data, the paper uses Seismosignal software to eliminate the waveform error point, the baseline correction, the filtering and denoising and so on, and the numerical integration. The acceleration peak and amplitude spectrum peak of each sample are obtained by conventional processing such as spectrum analysis. The response law of main monitoring points of dam under different source azimuth and different magnitude is analyzed and studied. The results are as follows: (1) when the source is on the right bank, the seismic response of the left abutment, the dam waist and the dam foot is basically the same. When the source is on the left bank, the left abutment is smaller than the dam waist. (2) under the condition of different source and magnitude, the earthquake response of the middle part of dam top is the strongest, at the same time, The seismic response is magnified with elevation. (3) the study of the components of the monitoring points shows that the parameters of the north-south component (approximate river direction in this paper) are larger than those of the other components. It shows that the dynamic load of reservoir water has a great influence on it. (4) the seismic response characteristics of different positions of the dam are mainly affected by magnitude and epicentral distance, except for the monitoring location and elevation. The relationship between the earthquake source and the location of the dam will also have an important impact. (5) the research results of the strong vibration characteristics of the dam can provide reference materials for the seismic design and daily safety observation of the dam.
【学位授予单位】：贵州大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TV312

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