本文選題：爆炸沖擊波 + 鋼管混凝土柱�。� 參考：《長安大學(xué)》2013年博士論文

【摘要】：建筑結(jié)構(gòu)除了承受靜動荷載以外，也可能遭受到由于爆炸恐怖襲擊、偶然燃?xì)獗ǖ雀鞣N因素引發(fā)的爆炸沖擊荷載。鋼管混凝土結(jié)構(gòu)由于其具有受力合理、承載力高、抗震性能好、施工方便、經(jīng)濟效益顯著等優(yōu)勢而在土木工程中得到廣泛應(yīng)用。研究該結(jié)構(gòu)在爆炸沖擊荷載下的動態(tài)響應(yīng)具有非常重要的理論意義及工程應(yīng)用價值。本文采用理論分析、試驗研究和數(shù)值模擬相結(jié)合的方法，對爆炸沖擊波與鋼管混凝土柱相互作用，爆炸荷載作用下鋼管混凝土柱的動態(tài)響應(yīng)、破壞模式和破壞機理等方面展開系統(tǒng)的研究。主要的研究工作和結(jié)論如下： （1）對鋼管混凝土柱構(gòu)件進行了2發(fā)3柱在不同藥量、不同比例距離下的靜爆試驗。測得柱迎爆面和背爆面柱的柱頂、柱中、柱底的超壓分布，以及振動加速度和最終位移，為準(zhǔn)確預(yù)測作用在鋼管混凝土柱上的爆炸荷載和評估鋼管混凝土柱的破壞形態(tài)及破壞機理提供試驗依據(jù)。試驗結(jié)果表明，對于剛度較大的結(jié)構(gòu)構(gòu)件來說，受迎爆面負(fù)壓區(qū)、背爆面的影響很小，可以忽略不計，僅考慮迎爆面的正壓區(qū)作用效應(yīng)；當(dāng)爆炸場中的反射環(huán)境較為簡單時，測量柱迎爆面反射超壓時，可以通過測量自由場中的反射超壓近似得到；并且得到了試驗爆炸荷載作用下相應(yīng)的鋼管混凝土柱的破壞形態(tài)。 （2）研究了爆炸沖擊波與鋼管混凝土柱之間的相互作用。通過試驗結(jié)果中的鋼管混凝土柱迎爆面的超壓分布，與已有的經(jīng)驗超壓公式進行比較，選擇TM5-1300中的各爆炸特征參數(shù)，為本文爆炸荷載的預(yù)測依據(jù)，為研究爆炸荷載作用下鋼管混凝土柱動態(tài)響應(yīng)提供可靠的爆炸荷載預(yù)測。 （3）建立爆炸沖擊波及其與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，采用流固耦合法，通過選取合理的材料模型、沙漏控制方法、邊界條件等因素，建立爆炸沖擊波與鋼管混凝土柱相互作用的數(shù)值模型。通過與試驗結(jié)果的對比，，驗證數(shù)值方法的正確性，并進行了參數(shù)分析。研究結(jié)果表明，含鋼率對爆炸波與柱相互作用的影響并不明顯，截面形狀和截面尺寸對爆炸波與柱相互作用的影響較為突出，相同的爆炸環(huán)境下，圓形截面柱迎爆面的爆炸荷載強度低于方形截面柱。 （4）基于等效單自由度體系對鋼管混凝土柱的動態(tài)響應(yīng)進行理論分析，引入圓形鋼管混凝土柱等效迎爆面的概念，采用延性系數(shù)計算出了等效體系在三角形脈沖荷載下的最大動位移，并通過與試驗的對比驗證了理論計算的可靠性。 （5）建立鋼管混凝土柱在爆炸荷載作用下動態(tài)響應(yīng)的數(shù)值模擬方法。并將數(shù)值模擬結(jié)果、試驗結(jié)果、理論計算結(jié)果進行對比分析。并通過大量的數(shù)值模擬，進行參數(shù)分析，結(jié)果表明，隨比例距離的增大，柱中點的水平最大位移和殘余位移明顯減小，并且衰減很快，當(dāng)比例距離大于0.3m/kg1/3時，可忽略比例距離對柱中水平位移的影響；降低加載速率和減小截面尺寸，能夠有效的降低鋼管混凝土柱在爆炸荷載下柱中的水平位移；提高混凝土和鋼材的抗壓強度、增大含鋼率，均能在一定程度上提高鋼管混凝土柱的抗爆性能；當(dāng)方形截面柱邊長等于圓形柱直徑時，相比圓形柱截面，盡管方形鋼管混凝土柱有近似于兩倍的慣性矩，但是方柱的截面不利于爆炸荷載的繞射，其迎爆面積相當(dāng)于圓柱等效迎爆面的四倍，因此，圓形截面柱有較強的抵御爆炸荷載的能力。 （6）鋼管混凝土柱在爆炸荷載作用下的破壞模式分別為：“高峰值低持時”的沖量荷載作用下，易發(fā)生剪切破壞；“低峰值高持時”的準(zhǔn)靜態(tài)荷載作用下，易于發(fā)生彎曲變形；而在動力荷載的作用下，鋼管混凝土柱傾向于發(fā)生彎剪破壞。
[Abstract]:In addition to building structures subjected to static loads, may also suffer due to the terrorist attacks of explosion, explosion shock loading caused by gas explosion and other various factors. Concrete filled steel tubular structure because of its reasonable stress, high bearing capacity, good anti-seismic performance, convenient construction, obvious economic benefit and advantages in civil engineering widely application. It has very important theoretical significance and engineering application value to research on dynamic response of the structure under blast loading. This paper uses the method of theoretical analysis, experimental research and numerical simulation on the combination of the explosion shock wave and concrete filled steel tube column interaction, the dynamic response of CFST columns under blast load, start system the study on the failure mode and failure mechanism. The main research work and conclusions are as follows:
(1) on the STCC component of 2 rounds of 3 columns in different dosage, different ratio of distance under static explosion test. The measured column blasting top surface and the back surface of the explosion, column, overpressure distribution at the bottom of the column, and the vibration acceleration and final displacement, to provide the experimental basis for accurate prediction the role in concrete filled steel tubular column on concrete filled steel tube column explosion load and evaluate the failure mode and the failure mechanism. The experimental results show that the structure stiffness of large, the face of blasting pressure area, the back blasting effect is small and can be ignored, only consider the blasting effect when the positive pressure zone; reflect the environment in the explosion field is relatively simple, measuring column face of blasting reflection overpressure, through reflection measurements in the free field pressure approximation; and the failure modes of concrete filled steel tubular columns corresponding test under explosion load.
(2) to investigate the interaction between shock wave and concrete filled steel tubular columns. Concrete filled steel tubular columns through the test results of the blast overpressure distribution of overpressure formula and the existing experience, choose the explosion characteristic parameters in TM5-1300, based on the prediction of blast loads, providing reliable explosion load the prediction for the research of response under explosion load dynamic steel pipe concrete column.
(3) establish a numerical simulation method of explosion shock wave and its interaction with the steel pipe concrete column. The explicit dynamic procedure based on ANSYS/LS-DYNA, using fluid solid coupling method, by selecting the reasonable material model, hourglass control method, boundary condition, a numerical model of explosion shock wave and concrete filled steel tube column interaction through the comparison. With the test results, verify the correctness of numerical method, and the parameters were analyzed. The results show that the influence of rate of steel of blast wave and column interaction is not obvious and the influence of section shape and section size of blast wave and column interaction is more prominent, the same explosive environment, the circular column of attack the explosion intensity of explosion load is below the square section column.
(4) the theoretical analysis of the dynamic equivalent single degree of freedom system of CFST column based on response, the equivalent of concrete filled circular steel tubular column blasting surface concept, ductility coefficient calculated by the equivalent system in the triangular pulse maximum displacement under load, and through the contrast test and verify the reliability of the theoretical calculation.
(5) the establishment of CFST columns under blast loading numerical simulation method. The dynamic response and the numerical simulation results and test results, the theoretical calculation results were compared and analyzed. Through numerical simulation, parameter analysis, results show that with increasing the ratio of the distance, the midpoint of the column level of maximum displacement and residual displacement decrease and decay quickly, when the ratio of the distance is greater than 0.3m/kg1/3, but ignoring the effect of the ratio of the distance of horizontal displacement of the column; reduce the loading rate and the size of section, can effectively reduce the horizontal displacement of CFST column under explosive load in the column; improve the compressive strength of concrete and steel, increasing with the the rate of steel, can improve the antiknock performance of concrete filled steel tubular columns in a certain extent; when the square section column is equal to the diameter of the circular column, compared with circular section column, as square steel The soil column has approximately two times of inertia moment, but the cross section of the square column is not conducive to the diffraction of the explosive load. The area of the blast hole is equivalent to four times that of the cylinder equivalent to the detonation surface. Therefore, the circular section column has a strong ability to resist explosion load.
(6) concrete filled steel tube column under explosion load failure mode are: "impulse load high peak low duration", prone to shear failure; quasi static loading is low to high peak ", prone to bending deformation; in dynamic loads, inclined concrete in place of steel pipe column bending shear failure.

【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)碩士學(xué)位論文 前1條

1 吳鵬;軸壓比對鋼管混凝土柱抗爆性能的影響研究[D];長安大學(xué);2014年

本文編號：1757984