【摘要】：隨著國民經(jīng)濟的不斷發(fā)展，由于燃氣泄漏、易燃易爆品堆置不當(dāng)、電器老化而引發(fā)的爆炸發(fā)生幾率逐漸增大，致使建筑結(jié)構(gòu)受到爆炸沖擊作用的可能性隨之增大。同時，由于全世界范圍內(nèi)恐怖襲擊時有發(fā)生，爆炸對于建筑結(jié)構(gòu)的威脅正與日俱增。要使結(jié)構(gòu)在爆炸沖擊荷載作用下有著較好的抗爆性能，避免結(jié)構(gòu)破壞，柱本身的抗爆性能起著非常重要的作用。復(fù)式空心鋼管混凝土柱具有承載力高、塑性好、抗彎剛度大的特點，被廣泛用做工程結(jié)構(gòu)中的重要受力構(gòu)件。因此研究復(fù)式空心鋼管混凝土柱的爆炸沖擊破壞效應(yīng)，進而建立其損傷評估方法具有重要的理論意義和工程應(yīng)用價值。本文采用試驗研究和數(shù)值模擬方法對爆炸荷載下復(fù)式空心鋼管混凝土柱的動態(tài)響應(yīng)和損傷評估進行系統(tǒng)研究，具有重要的理論意義和工程應(yīng)用價值。主要的研究工作和創(chuàng)新成果包括以下幾個方面： （1）研究了爆炸沖擊波與復(fù)式空心鋼管混凝土柱相互作用的數(shù)值模擬方法�；陲@式動力學(xué)程序ANSYS/LS-DYNA，采用ALE流固耦合的加載方式建立了考慮地面反射的爆炸荷載下鋼管混凝土柱、空氣及炸藥的有限元數(shù)值模型；進一步研究討論了空氣有限元網(wǎng)格劃分對數(shù)值模擬結(jié)果的影響。結(jié)果表明網(wǎng)格尺寸大小對沖擊波傳播的波形和傳播時間均有較大影響。沖擊波壓力峰值隨著網(wǎng)格尺寸的增加呈下降趨勢，網(wǎng)格密度越大，沖擊波壓力峰值與試驗采集壓力峰值越接近； （2）設(shè)計完成了兩發(fā)鋼管混凝土柱爆炸試驗。通過對測點壓力及柱宏觀變形的分析，結(jié)果表明在折合距離為1.1m/kg1/3的第一發(fā)試驗條件的爆炸荷載作用下，柱產(chǎn)生的變形屬于彈性變形，沒有塑性變形產(chǎn)生，柱仍有著良好的承載能力；在折合距離為0.14m/kg1/3第二發(fā)試驗條件的爆炸荷載作用下，復(fù)式空心鋼管混凝土柱迎爆面柱中發(fā)生了明顯的塑性彎曲變形。柱迎爆面柱底肋板上緣柱表面有一條細微未貫通裂縫存在。結(jié)果表明柱端部節(jié)點強度與構(gòu)件整體強度協(xié)調(diào)對提升復(fù)式空心混凝土柱的抗爆性能尤為重要； （3）研究了復(fù)式空心鋼管混凝土柱各參數(shù)對爆炸沖擊波與結(jié)構(gòu)柱的相互作用以及作用于柱上爆炸荷載規(guī)律的影響。通過參數(shù)分析，，結(jié)果表明增大空心率可以使柱核心區(qū)混凝土承受的壓力減小，從而在一定程度上改善復(fù)式空心鋼管混凝土柱的抗爆性能；即使正壓的作用時間一致，圓截面產(chǎn)生的壓力值也要低于方截面，因此圓截面抗爆性能要優(yōu)于方截面；提高混凝土強度等級對改善復(fù)式空心鋼管混凝土柱的抗爆性能影響不大；折合距離變化對復(fù)式空心鋼管混凝土柱的動態(tài)響應(yīng)和抗爆性能有較大影響。柱迎爆面位移峰值的增加率隨著折合距離的減小而迅速增加，壓力峰值的增加率遠大于折合距離的降低率，折合距離越小時，柱迎爆面壓強變化也相應(yīng)越敏感； （4）建立了基于復(fù)式空心鋼管混凝土柱中彎曲撓度變形量的超壓—沖量損傷準(zhǔn)則。在進行大量數(shù)值模擬試算的基礎(chǔ)上，建立了基于本文的復(fù)式空心鋼管混凝土柱損傷等級分界線，即P-I曲線。并擬合建立了P-I曲線數(shù)學(xué)表達式。同時將所得公式推廣到一般情況，建立了以迎爆面柱中撓度為指標(biāo)的復(fù)式空心鋼管混凝土柱彎曲變形損傷評估準(zhǔn)則。
[Abstract]:With the continuous development of the national economy, the probability of explosion caused by the improper stacking of the gas and the combustible and explosive products and the aging of the electric appliance gradually increases, so that the possibility of the building structure being impacted by the explosion is increased. At the same time, the threat of the explosion to the construction structure is increasing as a result of the terrorist attacks worldwide. The structure has a good anti-explosion performance under the action of an explosion impact load, so that the structure is avoided, and the anti-explosion property of the column itself can play a very important role. The composite hollow steel tube concrete column has the characteristics of high bearing capacity, good plasticity and high bending rigidity, and is widely used as an important force component in the engineering structure. Therefore, it is of great theoretical significance and application value to study the explosion impact failure effect of compound hollow steel tube concrete column, and then to set up its damage evaluation method. In this paper, the dynamic response and damage assessment of the composite hollow steel tube concrete column under the explosion load are systematically studied by means of the experimental research and the numerical simulation method, which is of great theoretical significance and engineering application value. The main research work and innovative outcomes include the following aspects: (1) The numerical simulation of the interaction between the blast shock wave and the composite hollow steel pipe concrete column is studied. Methods: Based on the explicit dynamic program ANSYS/ LS-DYNA, the finite element numerical model of the steel tube concrete column, air and explosive under the explosion load of the ground reflection is established by the loading mode of the ALE flow-solid coupling, and the numerical simulation results of the air finite element mesh are further studied. The results show that the size of the mesh has a great effect on the wave and the propagation time of the shock wave. The peak of the shock wave pressure decreases with the increase of the grid size, and the higher the grid density, the higher the peak value of the shock wave and the peak pressure of the test. approach; (2) design of two steel-filled steel pipe concrete Through the analysis of the pressure of the measuring point and the macro-deformation of the column, the results show that under the action of the explosion load of the first test condition with the folding distance of 1.1 m/ kg1/3, the deformation of the column belongs to the elastic deformation, no plastic deformation is generated, and the column is still good The load-bearing capacity of the composite hollow-steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled steel-filled concrete column has obvious plastic deformation under the action of explosion loading with a folding distance of 0.14m/ kg@@ The column is bent and deformed. The surface of the upper edge of the column bottom rib of the column-facing surface of the column is provided with a fine cross-section. The results show that the strength of the end node of the column and the overall strength of the component can be used to improve the anti-explosion of the composite hollow concrete column. The interaction between the explosion shock wave and the structural column and its action on the column are studied in (3). Through the analysis of the parameters, the results show that the increase of the hollow rate can reduce the pressure of the concrete in the core region of the column, so as to improve the anti-explosion performance of the composite hollow steel tube concrete column to a certain extent, even if the action time of the positive pressure is consistent, the pressure generated by the circular section The value is also lower than that of the square section, so the anti-explosion property of the circular section is superior to that of the square section, and the strength grade of the concrete is improved, the impact resistance of the composite hollow steel tube concrete column can not be greatly influenced, and the change of the folding distance on the dynamic response and the resistance of the compound hollow steel tube concrete column The rate of increase of the displacement peak of the column to the detonation surface increases rapidly with the reduction of the folding distance, the rate of increase of the pressure peak is much larger than the reduction rate of the folding distance, the more the folding distance is, the pressure of the column to the detonation surface The more sensitive the change is, (4) the deformation of the bending deflection in the concrete column based on the compound hollow steel pipe is established. Based on a large number of numerical simulation tests, this paper establishes the compound hollow steel pipe concrete column damage based on this paper. Class boundary, that is, the P-I curve. The mathematical expression of P-I curve is given. At the same time, the formula is generalized to the general situation, and the compound hollow steel pipe concrete with the index of deflection in the column is established.
【學(xué)位授予單位】：長安大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2013
【分類號】：TU398.9

【引證文獻】

相關(guān)博士學(xué)位論文 前3條

1 都浩;城市環(huán)境中建筑爆炸荷載模擬及鋼筋混凝土構(gòu)件抗爆性能分析[D];天津大學(xué);2009年

2 師燕超;爆炸荷載作用下鋼筋混凝土結(jié)構(gòu)的動態(tài)響應(yīng)行為與損傷破壞機理[D];天津大學(xué);2009年

3 李天華;爆炸荷載下鋼筋混凝土板的動態(tài)響應(yīng)及損傷評估[D];長安大學(xué);2012年

本文編號：2508865