肯斯瓦特泄洪洞进水塔静动力分析及安全性评定
发布时间：2018-10-24 14:04
【摘要】：我国是一个多地震的国家,许多水利枢纽工程处于高烈度的危险区内。尤其是“5.12”汶川特大地震后,拟修建和已修建的水利枢纽工程中的进水塔抗震问题引起工程界的高度重视,那么研究进水塔的静动力分析及安全性评定是必不可少的。本文采用有限元分析方法,选择肯斯瓦特水利枢纽的泄洪洞进水塔工程为研究对象,做了以下主要工作:(1)分析岸塔式进水塔研究的现状、进展及研究的方法。(2)依据设计图纸和相关资料,建立三维有限元模型;研究了五种静力工况下泄洪洞进水塔应力、位移分布,并对结果进行分析及稳定性评价。(3)在地震荷载作用下,进行了模态分析、地震反应谱分析及时间历程分析;并对相应的结果进行对比分析及稳定性评价。(4)用附加质量理论研究了泄洪洞进水塔结构含水振动特性,并和无水情况下对比,分析相应的结果及稳定性评价。(5)用功率谱密度方法对泄洪洞进水塔进行动力分析,从概率角度对进水塔安全性进行评估。对全文的研究分析,得出以下主要结论:(1)在五种典型工况下结构的水平位移较大且变化不大,竖直位移较小,满足安全性能要求。在正常水位下事故闸门关闭时,闸门处的局部第一主应力和第三主应力都比较大,混凝土的抗拉难以满足要求,需对局部加强与改善。(2)结构在地震反应谱作用下,顺流激励最大拉应力和垂流方向激励最大拉应力都较大,应对产生应力的局部应作加强处理。(3)对特定地震波作用下的时间历程响应分析与反应谱分析结果相吻合,这说明两者计算方法的可靠性。(4)在含水振动的条件下,结构的位移和应力都有大幅度的增长。所以在考虑动水压力作用的条件下,必须对结构进行加固处理。(5)结构在地震荷载作用下开裂的概率比较大,所以必须对结构进行适当的配筋或采取一些加固手段进行处理,以保证结构在强震下不发生垮塌。(6)计算结果的自相关加速度PSD谱比速度PSD谱和位移PSD谱更加清楚的显示了参与振动的结构频率,可用于精细检测结构物振动所含有的频率。通过对肯斯瓦特泄洪洞进水塔静动力分析及安全性评定的研究,所用的研究方法可为勘测、设计单位及施工单位等提供参考。为类似泄洪洞进水塔结构的抗震稳定性设计、校核、预测提供参考依据。
[Abstract]:China is a country with many earthquakes, and many hydro-junction projects are in high intensity dangerous areas. Especially after the "5.12" Wenchuan earthquake, the aseismic problem of intake tower in the water conservancy project to be built and built has attracted great attention in the engineering circle, so it is necessary to study the static and dynamic analysis and safety evaluation of the intake tower. In this paper, the finite element analysis method is used to select the intake tower project of the flood discharge tunnel of the Keneswatt Water Conservancy Project as the research object. The main works are as follows: (1) analyzing the present situation of the research on the coastal tower intake tower. (2) based on the design drawings and related data, the three-dimensional finite element model is established, and the stress and displacement distribution of the intake tower in five kinds of static conditions are studied. The results are analyzed and evaluated. (3) Modal analysis, seismic response spectrum analysis and time history analysis are carried out under the action of earthquake load. The corresponding results are compared and evaluated. (4) the characteristics of the water bearing vibration of the intake tower structure of the flood discharge tunnel are studied by the theory of additional mass, and compared with that in the case of no water. The corresponding results and stability evaluation are analyzed. (5) the power spectral density method is used to analyze the dynamic characteristics of the intake tower and the safety of the tower is evaluated from the point of view of probability. The main conclusions are as follows: (1) under five typical working conditions, the horizontal displacement of the structure is large and little change, and the vertical displacement is small, which can meet the requirements of safety performance. When the emergency gate closes under normal water level, the local first principal stress and the third principal stress at the gate are both relatively large, and the tensile resistance of concrete is difficult to meet the requirements. (2) under the action of seismic response spectrum, the structure needs to be strengthened and improved. The maximum tensile stress in downstream excitation and the maximum tensile stress in vertical direction should be strengthened. (3) the results of time history response analysis and response spectrum analysis agree well with the results of response spectrum analysis. This shows the reliability of the two methods. (4) under the condition of water vibration, the displacement and stress of the structure increase by a large margin. Therefore, under the consideration of dynamic water pressure, the structure must be strengthened. (5) the probability of structure cracking under earthquake load is relatively high, so the structure must be properly reinforced or treated with some reinforcement measures. In order to ensure that the structure does not collapse under strong earthquake. (6) compared with velocity PSD spectrum and displacement PSD spectrum, the autocorrelation acceleration PSD spectrum shows the frequency of the structure participating in the vibration more clearly, and can be used to detect the frequency of the vibration of the structure. Through the study of static and dynamic analysis and safety evaluation of the intake tower of the Kenswart flood discharge tunnel, the research methods used can provide reference for survey, design unit and construction unit. It provides reference basis for seismic stability design, check and forecast of similar flood discharge tunnel intake tower structure.
【学位授予单位】：石河子大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV31
本文编号：2291621
[Abstract]:China is a country with many earthquakes, and many hydro-junction projects are in high intensity dangerous areas. Especially after the "5.12" Wenchuan earthquake, the aseismic problem of intake tower in the water conservancy project to be built and built has attracted great attention in the engineering circle, so it is necessary to study the static and dynamic analysis and safety evaluation of the intake tower. In this paper, the finite element analysis method is used to select the intake tower project of the flood discharge tunnel of the Keneswatt Water Conservancy Project as the research object. The main works are as follows: (1) analyzing the present situation of the research on the coastal tower intake tower. (2) based on the design drawings and related data, the three-dimensional finite element model is established, and the stress and displacement distribution of the intake tower in five kinds of static conditions are studied. The results are analyzed and evaluated. (3) Modal analysis, seismic response spectrum analysis and time history analysis are carried out under the action of earthquake load. The corresponding results are compared and evaluated. (4) the characteristics of the water bearing vibration of the intake tower structure of the flood discharge tunnel are studied by the theory of additional mass, and compared with that in the case of no water. The corresponding results and stability evaluation are analyzed. (5) the power spectral density method is used to analyze the dynamic characteristics of the intake tower and the safety of the tower is evaluated from the point of view of probability. The main conclusions are as follows: (1) under five typical working conditions, the horizontal displacement of the structure is large and little change, and the vertical displacement is small, which can meet the requirements of safety performance. When the emergency gate closes under normal water level, the local first principal stress and the third principal stress at the gate are both relatively large, and the tensile resistance of concrete is difficult to meet the requirements. (2) under the action of seismic response spectrum, the structure needs to be strengthened and improved. The maximum tensile stress in downstream excitation and the maximum tensile stress in vertical direction should be strengthened. (3) the results of time history response analysis and response spectrum analysis agree well with the results of response spectrum analysis. This shows the reliability of the two methods. (4) under the condition of water vibration, the displacement and stress of the structure increase by a large margin. Therefore, under the consideration of dynamic water pressure, the structure must be strengthened. (5) the probability of structure cracking under earthquake load is relatively high, so the structure must be properly reinforced or treated with some reinforcement measures. In order to ensure that the structure does not collapse under strong earthquake. (6) compared with velocity PSD spectrum and displacement PSD spectrum, the autocorrelation acceleration PSD spectrum shows the frequency of the structure participating in the vibration more clearly, and can be used to detect the frequency of the vibration of the structure. Through the study of static and dynamic analysis and safety evaluation of the intake tower of the Kenswart flood discharge tunnel, the research methods used can provide reference for survey, design unit and construction unit. It provides reference basis for seismic stability design, check and forecast of similar flood discharge tunnel intake tower structure.
【学位授予单位】：石河子大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV31
【参考文献】
相关期刊论文 前1条
1 何蕴龙，陆述远，，段亚辉;重力坝地震动力响应分析[J];世界地震工程;1998年03期
本文编号：2291621
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