考虑含水率对强度参数影响的巷道围岩蠕变损伤模型

    Creep damage model of roadway surrounding rock considering the influence of water content on strength parameters

    • 摘要: 为了研究含水率对岩石蠕变特性的影响,开展不同含水率作用下岩石的蠕变特性试验,分析含水率对岩石长期强度和蠕变特性的影响,在此基础上进一步分析含水率对强度参数劣化的影响,基于损伤力学建立一种新型的岩石蠕变损伤本构模型,采用试验数据对建立的模型参数进行识别,进而验证所建立模型的合理性与正确性。结果表明:对于衰减蠕变而言,含水率越大,衰减蠕变时间越短且可以更快地进入稳定蠕变变形阶段;对于稳定蠕变变形而言,高含水率可能使得岩石更易发生稳定变形;而在加速蠕变变形方面,高含水率条件会促进岩石变形速率的加快。考虑含水率对强度参数影响的巷道围岩蠕变损伤模型在描述岩石蠕变全过程曲线方面表现出色。模型曲线与试验曲线之间的相关性系数均高于0.93,这表明所提出的蠕变损伤模型在描述岩石蠕变行为方面具有高度的正确性。该模型不仅能够准确描述岩石在衰减和稳定蠕变阶段的特性,还能够较为精确地描述其加速蠕变的情况,这有助于全面理解岩石的蠕变行为。

       

      Abstract: In order to study the influence of water content on the creep characteristics of rock, the creep characteristics test of rock under different water content is carried out. The influence of water content on the long-term strength and creep properties of rock is analyzed. On this basis, the influence of water content on the deterioration of strength parameters is further analyzed. A new creep damage constitutive model of rock is established based on damage mechanics. The model parameters are identified by experimental data. Then, the rationality and correctness of the established model are verified. The results show that for the decay creep, the greater the water content, the shorter the decay creep time and the faster it can enter the stable creep deformation stage. For stable creep deformation, high water content may make rock more prone to stable deformation. In terms of accelerated creep deformation, high water content conditions will promote the acceleration of rock deformation rate. The creep damage model of roadway surrounding rock considering the influence of water content on strength parameters is excellent in describing the whole process curve of rock creep. The correlation coefficient between the model curves and the test curves are higher than 0.93. This indicates that the proposed creep damage model is highly correct in describing the creep behavior of rock. This model can not only accurately describe the characteristics of rock in the attenuation and stable creep stage, but also describe its accelerated creep more accurately, which helps to fully understand the creep behavior of rock.

       

    /

    返回文章
    返回