论文部分内容阅读
油砂是一种富含天然沥青的沉积砂。作为一种软化材料,油砂的蠕变性质较松砂和正常固结黏土等硬化材料更为复杂。通过开展油砂三轴蠕变试验,获得了不同应力和应变状态下油砂的蠕变特性;讨论了蠕变势与塑性势之间的关系,提出了等效变形过程的概念,分析等效变形过程的微观机制;讨论了蠕变速率与时间和不可恢复应变之间的关系,提出采用不可恢复应变作为内变量可以描述复杂条件下油砂的蠕变性质,并据此提出了油砂的内变量蠕变模型;应用临界状态理论,分析了硬化型和软化型土的蠕变性质;讨论了剪切带对密砂蠕变性质的影响。
Oil sands are a kind of sediment sand rich in natural bitumen. As a softening material, the oil cinder is more complicated than the hardened materials such as loose sand and normally consolidated clay. Through the triaxial creep test of oil sands, the creep characteristics of oil sands under different stress and strain conditions were obtained. The relationship between creep potential and plastic potential was discussed. The concept of equivalent deformation process was put forward and the equivalent The relationship between creep rate and time and non-recoverable strain is discussed. The creep property of oil sands under complex conditions is described by using unrecoverable strain as internal variable, and the oil sand’s The creep model of internal variable was established. The critical state theory was applied to analyze the creep properties of hardened and softened soils. The effect of shear zone on the creep properties of sand was discussed.