采用分级加/卸载方式对深井泥岩试件进行峰前/峰后单轴短时蠕变试验,得到了差异性较强的蠕变试验曲线。对峰前各级横向蠕变试验曲线的Ⅰ、Ⅱ阶段进行Burgers模型拟合,对峰后轴向/横向蠕变试验曲线暨再破坏后曲线进行Boltzmann函数拟合,得到相关性强的拟合函数并确定了待定系数。深井泥岩的峰后蠕变破坏强度达峰前常规蠕变破坏强度的95.72%,但维系时间短、可靠性低。深井泥岩于峰值后再承载至历史记忆值时,其总变形量明显增加、蠕变演变为变形主体,且其横向蠕变特性显著强于轴向蠕变特性,因此横向蠕变成为实际工程中围岩变形控制的重点。
Uniaxial short-term creep tests of front and rear ultimate strength for mudstone in deep site were carried out based on stage loading and unloading methods, creep curves with strong otherness were obtained. Fitting I and Ⅱ stage of ra6ical creep test curves missing ultimate strength by Burgers model and fitting axial or radical creep test curves and their extended parts rearwards the ultimate strength by Boltzmann function, functions with strong correlativity and coefficients are determined. Although creep strength ratio rearwards the ultimate strength to creep strength missing the ultimate strength may be up to 95.72~, but the state has lower reliability and can only hold for short time. When the loads acted on mudstone rearwards the ultimate strength approach its original standard, th~ complete deformation increases obviously and is mainly made up of creep strain. Therefore, restraining radical deformation may be important in actual engineering from traditional argument that radical creep features of rock should be more typical than its axial creep features.