混凝土应力-应变曲线试验研究与随机损伤本构模型

发布时间：2018-01-22 05:12

本文关键词： 随机损伤本构模型统计分析普通混凝土纤维混凝土喷射混凝土力　出处：《西安建筑科技大学》2015年硕士论文　论文类型：学位论文

【摘要】：现有的非确定性本构模型主要针对普通混凝土,对纤维混凝土、喷射混凝土的研究较少,并且很少考虑到由于混凝土材料组成、施工工艺的不同对混凝土本构模型的影响,缺乏统一的混凝土本构模型。本文所建立的随机损伤本构模型可以通过分布函数的选择,以实现对不同类型混凝土的区别研究,进而建立了多种混凝土的统一随机损伤本构模型。本文分别对设计强度等级为C30的普通混凝土、钢纤维混凝土、聚丙烯纤维混凝土、喷射混凝土试件进行了轴心受压应力-应变曲线试验研究。通过试验分析了各组混凝土单轴受压的破坏过程和应力-应变曲线的特点;利用试验结果,对各组混凝土应力-应变曲线特征参数(包括峰值应力、峰值应变、弹性模量、极限应变)进行了统计分析,K-S检验结果表明,各类混凝土的应力-应变曲线特征参数均不拒绝正态分布、对数正态分布和Weibull分布,为建立随机损伤本构模型奠定了基础。根据平行杆模型原理,在应力-应变曲线特征参数统计分析的基础上,建立了能够针对多种混凝土的统一随机损伤本构模型,根据轴心受压试验结果确定了随机损伤本构模型的参数。并将正态分布模型、对数正态分布模型和Weibull分布模型的计算结果与试验结果进行了对比分析,研究结果表明,Weibull分布更适合普通混凝土和喷射混凝土的随机损伤本构模型;而对钢纤维混凝土和聚丙烯纤维混凝土的随机损伤本构模型则对数正态分布更好。
[Abstract]:The existing non-deterministic constitutive models are mainly for ordinary concrete, fiber reinforced concrete, shotcrete less research, and rarely consider because of the composition of concrete materials. The influence of different construction technology on concrete constitutive model is lack of unified concrete constitutive model. The random damage constitutive model established in this paper can be selected by distribution function. In order to achieve the difference between different types of concrete, the unified stochastic damage constitutive model of various concrete is established. In this paper, the design strength of C30 ordinary concrete, steel fiber concrete respectively. The axial compression stress-strain curves of polypropylene fiber reinforced concrete and shotcrete specimens were studied. The failure process of uniaxial compression and the characteristics of stress-strain curves of each group of concrete under uniaxial compression were analyzed. Based on the test results, the characteristic parameters of stress-strain curves (including peak stress, peak strain, elastic modulus, limit strain) of concrete are analyzed statistically and the results of K-S test show that. The characteristic parameters of stress-strain curves of all kinds of concrete do not refuse normal distribution, logarithmic normal distribution and Weibull distribution, which lays the foundation for the establishment of stochastic damage constitutive model, according to the principle of parallel bar model. Based on the statistical analysis of the characteristic parameters of stress-strain curves, a unified stochastic damage constitutive model for concrete is established. The parameters of the random damage constitutive model are determined according to the results of axial compression test. The results of the logarithmic normal distribution model and the Weibull distribution model are compared with the experimental results. Weibull distribution is more suitable for stochastic damage constitutive model of ordinary concrete and shotcrete. The random damage constitutive model of steel fiber concrete and polypropylene fiber concrete is better than the logarithmic normal distribution.
【学位授予单位】：西安建筑科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU528

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