低速冲击荷载下低碳钢的损伤本构模型研究

发布时间：2018-03-09 15:40

本文选题：横向冲击　切入点：损伤　出处：《烟台大学》2017年硕士论文　论文类型：学位论文

【摘要】：钢结构建筑被称为“绿色建筑”,受到众多房地产开发商的青睐,并凭借自身独特的优点广泛应用于各种建筑中。钢结构在服役过程中会遭受车辆、船舶或者其他动力荷载的撞击,钢结构建筑受到撞击时会产生不可恢复的损伤。国内外关于钢结构受冲击性能以及钢材损伤本构模型的研究有很多,但关于冲击荷载和损伤对钢结构共同影响的研究却很少,因此冲击荷载下钢材的损伤本构模型还需进一步研究。本文对低速冲击荷载下低碳钢的损伤本构模型进行了研究,主要内容包括以下几点:(1)根据连续介质损伤力学理论、Lemaitre应变等价原理、Von Mises屈服准则、各向同性损伤理论等理论给出了静力荷载下低碳钢达到极限强度后的损伤本构模型。修正了原始的Cowper-Symonds模型,给出了冲击荷载下同时考虑损伤与应变率效应的Cowper-Symonds模型。进行了钢材静力拉伸试验和动力材性试验,将模型计算结果与试验结果进行对比,验证本文给出模型的正确性,并用文献中的数据进一步验证了模型的准确性。结果表明:本文给出模型的计算结果与试验结果较为接近,因此给出的模型是可行的。(2)进行了圆管的抗冲击试验,为验证本文给出的损伤本构模型是否可以应用在构件有限元模型中提供了试验依据。并对试验得到的抗冲击性能指标进行了分析。(3)运用ABAQUS有限元软件分别建立了圆钢管在不考虑损伤与考虑损伤状态下的有限元模型,并对比分析了不同状态下的有限元模拟结果与试验结果。结果表明:考虑损伤的有限元模拟结果与试验结果更接近,本文给出的损伤本构模型可以在构件有限元模拟中运用;为了进一步验证本文给出的本构模型的可靠性,根据文献中试验资料建立了考虑损伤的有限元模型,并将模拟结果与试验结果以及以前的模拟结果对比分析,得出本文给出的损伤本构模型是可靠的。
[Abstract]:Steel structures, known as "green buildings", are favored by many real estate developers and are widely used in various buildings by virtue of their unique advantages. Due to the impact of ship or other dynamic loads, steel structures will suffer irrecoverable damage when they are impacted. There are a lot of researches on the impact behavior of steel structures and the constitutive models of steel damage at home and abroad. However, there are few studies on the influence of impact load and damage on steel structure, so the damage constitutive model of steel under impact load needs further study. In this paper, the damage constitutive model of low carbon steel under low speed impact load is studied. The main contents include the following points: 1) according to the theory of continuum damage mechanics, we present the Von Mises yield criterion based on the Lemaitre strain equivalence principle. Based on isotropic damage theory and other theories, the damage constitutive model of low carbon steel under static load after reaching the ultimate strength is given. The original Cowper-Symonds model is modified. A Cowper-Symonds model considering both damage and strain rate effects under impact load is presented. The static tensile test of steel and the test of dynamic material properties are carried out. The results of model calculation and test are compared to verify the correctness of the model given in this paper. The accuracy of the model is further verified by the data in the literature. The results show that the calculated results of the model in this paper are close to the experimental results, so the model given in this paper is feasible. In order to verify whether the damage constitutive model presented in this paper can be applied to the finite element model of members, the experimental basis is provided. The finite element model of circular steel tube without considering damage and considering damage state, The finite element simulation results of different states are compared with the experimental results. The results show that the damage constitutive model can be used in the finite element simulation of the components. In order to further verify the reliability of the constitutive model presented in this paper, a finite element model considering damage is established according to the experimental data in the literature, and the simulation results are compared with the experimental results and the previous simulation results. It is concluded that the damage constitutive model given in this paper is reliable.
【学位授予单位】：烟台大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU391;TU317

【参考文献】