水岩作用下砂岩劣化损伤统计本构模型

发布时间：2018-04-17 15:03

本文选题：水岩作用 + 浸泡-风干循环　；参考：《岩土力学》2017年03期

【摘要】：水库蓄水运行后,库水位反复升降变化对库岸边坡岩土体来说是一种疲劳作用,水岩作用下边坡岩体力学性质的劣化将影响整个边坡的稳定。基于此,在前期浸泡-风干循环水岩作用试验数据分析基础上,根据水岩作用过程中砂岩三轴压缩试验应力-应变曲线的特点,借助连续损伤力学和统计理论,将浸泡-风干循环水岩作用的损伤效应耦合到损伤统计本构模型中,并重点考虑了压密段的影响,分段建立了水岩作用下砂岩的统计损伤本构方程。对比分析表明,所建立的分段统计损伤本构模型计算与试验曲线符合较好,说明所建立的统计损伤本构方程可以较好地反映砂岩在浸泡-风干循环水岩作用的损伤效应,在水岩作用过程中,本构模型第2段的Weibull分布参数m和F_0均逐渐减小,反映了水岩作用下砂岩脆性逐渐减弱,宏观强度逐渐降低的力学特性。研究成果对大量存在的库岸边坡长期变形稳定分析具有较好的参考价值,同时,相关分析方法也可以为类似试验提供参考。
[Abstract]:The repeated fluctuation of reservoir water level is a kind of fatigue action to the rock and soil on the bank of the reservoir after the water storage operation. The deterioration of the rock mass mechanical properties of the slope under the action of water rock will affect the stability of the whole slope.Based on this, based on the analysis of the experimental data of soaking and air-drying circulating water rocks, and according to the characteristics of stress-strain curves of sandstone triaxial compression tests during the process of water-rock interaction, the continuous damage mechanics and statistical theory are used.The damage effect of steeping-air drying circulating water rock is coupled to the damage statistical constitutive model, and the statistical damage constitutive equation of sandstone under the action of water-rock is established by stages, especially considering the influence of compaction section.The comparison and analysis show that the calculated results of the piecewise statistical damage constitutive model are in good agreement with the experimental curve, which indicates that the established statistical damage constitutive equation can well reflect the damage effect of sandstone under the action of soaking and air-drying circulating water rocks.In the process of water-rock interaction, the Weibull distribution parameters m and F _ 0 of the second section of the constitutive model are gradually reduced, which reflects the mechanical characteristics of sandstone brittleness weakening and macroscopic strength decreasing gradually under the action of water-rock.The results of the study have a good reference value for the long-term deformation stability analysis of a large number of reservoir bank slopes. At the same time, the relevant analysis methods can also provide a reference for similar tests.
【作者单位】：三峡大学三峡库区地质灾害教育部重点实验室;
【基金】：湖北省自然科学基金重点项目(No.2015CFA140) 国家自然科学基金资助项目(No.51309141,No.51679127,No.51439003)~~
【分类号】：TV223

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