【摘要】：我國是一個多地震的國家,許多水利樞紐工程處于高烈度的危險區(qū)內(nèi)。尤其是“5.12”汶川特大地震后,擬修建和已修建的水利樞紐工程中的進(jìn)水塔抗震問題引起工程界的高度重視,那么研究進(jìn)水塔的靜動力分析及安全性評定是必不可少的。本文采用有限元分析方法,選擇肯斯瓦特水利樞紐的泄洪洞進(jìn)水塔工程為研究對象,做了以下主要工作:(1)分析岸塔式進(jìn)水塔研究的現(xiàn)狀、進(jìn)展及研究的方法。(2)依據(jù)設(shè)計(jì)圖紙和相關(guān)資料,建立三維有限元模型;研究了五種靜力工況下泄洪洞進(jìn)水塔應(yīng)力、位移分布,并對結(jié)果進(jìn)行分析及穩(wěn)定性評價。(3)在地震荷載作用下,進(jìn)行了模態(tài)分析、地震反應(yīng)譜分析及時間歷程分析;并對相應(yīng)的結(jié)果進(jìn)行對比分析及穩(wěn)定性評價。(4)用附加質(zhì)量理論研究了泄洪洞進(jìn)水塔結(jié)構(gòu)含水振動特性,并和無水情況下對比,分析相應(yīng)的結(jié)果及穩(wěn)定性評價。(5)用功率譜密度方法對泄洪洞進(jìn)水塔進(jìn)行動力分析,從概率角度對進(jìn)水塔安全性進(jìn)行評估。對全文的研究分析,得出以下主要結(jié)論:(1)在五種典型工況下結(jié)構(gòu)的水平位移較大且變化不大,豎直位移較小,滿足安全性能要求。在正常水位下事故閘門關(guān)閉時,閘門處的局部第一主應(yīng)力和第三主應(yīng)力都比較大,混凝土的抗拉難以滿足要求,需對局部加強(qiáng)與改善。(2)結(jié)構(gòu)在地震反應(yīng)譜作用下,順流激勵最大拉應(yīng)力和垂流方向激勵最大拉應(yīng)力都較大,應(yīng)對產(chǎn)生應(yīng)力的局部應(yīng)作加強(qiáng)處理。(3)對特定地震波作用下的時間歷程響應(yīng)分析與反應(yīng)譜分析結(jié)果相吻合,這說明兩者計(jì)算方法的可靠性。(4)在含水振動的條件下,結(jié)構(gòu)的位移和應(yīng)力都有大幅度的增長。所以在考慮動水壓力作用的條件下,必須對結(jié)構(gòu)進(jìn)行加固處理。(5)結(jié)構(gòu)在地震荷載作用下開裂的概率比較大,所以必須對結(jié)構(gòu)進(jìn)行適當(dāng)?shù)呐浣罨虿扇∫恍┘庸淌侄芜M(jìn)行處理,以保證結(jié)構(gòu)在強(qiáng)震下不發(fā)生垮塌。(6)計(jì)算結(jié)果的自相關(guān)加速度PSD譜比速度PSD譜和位移PSD譜更加清楚的顯示了參與振動的結(jié)構(gòu)頻率,可用于精細(xì)檢測結(jié)構(gòu)物振動所含有的頻率。通過對肯斯瓦特泄洪洞進(jìn)水塔靜動力分析及安全性評定的研究,所用的研究方法可為勘測、設(shè)計(jì)單位及施工單位等提供參考。為類似泄洪洞進(jìn)水塔結(jié)構(gòu)的抗震穩(wěn)定性設(shè)計(jì)、校核、預(yù)測提供參考依據(jù)。
[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.
【學(xué)位授予單位】：石河子大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2014
【分類號】：TV31

【參考文獻(xiàn)】

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1 何蘊(yùn)龍，陸述遠(yuǎn)，，段亞輝;重力壩地震動力響應(yīng)分析[J];世界地震工程;1998年03期

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