Discovered from the aspects of macroscopic genesis and microscopic genesis of damage mechanism were, in this paper, the fuzziness and randomness of damage evolution. So, it was deduced here that generalized damage functional should be set up under double mathematical coverages of fuzziness and randomness, by which generalized uncertain space was established. Initial stress field was formulated particularly in this paper to express non-linear damage field evolution. Accordingly, under plane strain state, anisotropic initial fuzzy-stochastic damage field submitting to β-probabilistic distribution was deduced on the basis of triple typical fuzzy damage distribution models, namely, half depressed distribution, swing distribution, and combined swing distribution. Meanwhile, by the help of initial fuzzy-stochastic damage effective tensor, offered comprehensively was fuzzy-stochastic numerical model on viscous-elasto-plasto initial damage-stress field. Furthermore, established here was critical damage vector algorithm, based on which damage effective tensor and fuzzy-stochastic effective elastic matrixes group were formulated under plane strain state. Viscous-elasto-plasto fuzzy-stochastic damage constitution model based on modified damage-Mohr-Coulomb failure criterion was in this paper deduced absolutely associated with general normal function of viscous-elasto-plasto strain-ratio evolution of damaged material. Fuzzy-stochastic damage increment functional was formulated on the basis of fuzzy attenuation algorithm model by the help of concentrating-damage vector, with which realized was the general expression on unloading model of viscous-elasto-plasto fuzzy-stochastic damage increment functional. Damage development and generalized reliability under phased implementation of typical foundation ditch excavation were studied deeply by the help of non-linear fuzzy-stochastic damage mechanics model under spatial discreteness and variation of material parameters, by which, it is discovered that fuzzy-stochastic damage-development model rationalizes damage field distribution according to material spatial strength dissipation and such complex macro-mechanical characteristics of geo-strueture as hardening, yielding, failure, re-distribution of vector field, and healing induced by micro-concentration, as well as rupture of material particle, were disclosed thoroughly in this paper studies. Thereby, the conclusions achieved is helpful for realization of overall analysis and accurate simulation on geo-engineering.%从损伤形成的宏、微观机理出发揭示了损伤演化的模糊性和随机特征,提出了损伤泛函成立于模糊、随机双层数学覆盖之下进而构建了研究广义损伤泛函的广义非确定空间.提出了非线性损伤发展所依据的初始应力场;基于三种典型模糊损伤分布:降半分布、秋千分布、组合秋千分布,提出了平面应变下服从随机β分布的各向异性初始模糊随机损伤场,并基于初始模糊随机损伤有效张量给出粘-弹-塑性初始损伤应力场的模糊随机数值模型.提出并构造了损伤矢量临界值算法并基于此推导了平面应变条件下的损伤有效张量及模糊随机有效弹性矩阵族;由损伤材料粘-弹-塑性应变率演化通式提出了基于修正:Mohr-Coulomb损伤破坏准则的粘-弹-塑性模糊随机损伤本构模型.就土方开挖的损伤增益特征,提出并构造了基于模糊衰减模型的模糊随机损伤增量方程,实现了对粘-弹-塑性模糊随机损伤增量方程卸载模型的全面阐述.考虑场内参数的空间离散及随机变异特征,借助本文提出的非线性模糊随机损伤力学模型,就某典型基坑工程开挖进阶过程中的损伤演变及广义可靠性进行了深入探讨,过程揭示了模糊随机损伤模型可以根据场内结构及材料强度耗散情况随时对损伤分布做出调整,以充分反映材料细观粒子间的凝聚或断裂造成的岩土结构宏观方面硬化-屈服-破坏-重分布-愈合等复杂力学性征,得到的规律性认识对于实现岩土工程全面化、精确化分析研究有重要意义.
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