高速铁路隧道基底混凝土结构的随机损伤模型

发布时间：2018-03-31 14:26

本文选题：高速铁路　切入点：隧道基底　出处：《中国铁道科学》2017年01期

【摘要】：基于热力学原理与能量耗散原理,针对高速铁路隧道基底混凝土结构"拉—压—拉—压"反复受力特点,定义双标量损伤变量,引入硬化函数,建立混凝土受拉、受压条件下基于修正弹塑性亥姆霍兹自由能的随机损伤本构模型。在有效应力空间,根据塑性力学正交法则推导损伤变量的演化法则;在概率密度演化方程求解的基础上,建立"弹性预测—塑性修正—损伤修正"数值分析算法,并进行程序二次开发,实现对随机损伤本构模型的求解。通过与混凝土单轴拉伸、单轴压缩室内试验结果对比,验证所建立随机损伤本构模型的准确性和适用性。该模型既可在均值意义上反映混凝土受拉、受压的应力—应变关系,也可以在概率意义上模拟其离散范围,较为全面地反映了混凝土受力行为的非线性与随机性;可用于计算分析隧道基底混凝土结构的损伤演化规律及损伤疲劳寿命。
[Abstract]:Based on the principle of thermodynamics and energy dissipation, the double scalar damage variable is defined, and the hardening function is introduced to establish the tension of concrete.A stochastic damage constitutive model based on modified elastoplastic Helmholtz free energy under compression condition.In the effective stress space, the evolution rule of damage variable is derived according to the orthogonal rule of plastic mechanics, and the numerical analysis algorithm of "elastic prediction-plastic correction and damage correction" is established on the basis of solving the evolution equation of probability density.The second program is developed to solve the stochastic damage constitutive model.The accuracy and applicability of the proposed stochastic damage constitutive model are verified by comparing the results of laboratory tests with concrete uniaxial tension and uniaxial compression.It can be used to calculate and analyze the damage evolution law and damage fatigue life of the concrete structure of tunnel base.
【作者单位】：中国铁道科学研究院研究生部;中国铁道科学研究院铁道建筑研究所;中国铁道科学研究院;
【基金】：国家自然科学基金高铁联合基金重点资助项目(U1434211) 中国铁路总公司科技研究开发计划重大项目(YS2016G-02) 铁道科学技术研究发展中心科研项目(J2014G004) 中国铁道科学研究院国际合作项目(2015YJ143);中国铁道科学研究院科技开发基金资助项目(2015YJ039)
【分类号】：U459.1

【参考文献】