中文摘要：

Boom Clay为比利时第三纪细密黏土沉积物，其力学性质十分复杂，尤其是其显著的蠕变特性更需进行广泛的试验和深入的理论研究。通过室内固结和三轴蠕变试验，研究不同应力水平下的蠕变特性；建立以不可恢复应变为变量的不显含时间的分离型屈服面蠕变本构模型，避免了传统显含时间项的蠕变模型在土体经历加、卸载过程等复杂工况的实际计算中，具体蠕变时间确定的难题。将所建新型蠕变模型在 ABAQUS 软件中实现二次开发，并通过不同蠕变参数下的基本性能检验和蠕变试验的模拟，验证了所建模型的正确性和所编程序的可靠性。

英文摘要：

The Boom Clay is a kind of tertiary uniform and fine clay sediment. Because of its complicated mechanical characteristics,especially evident creep characteristic,a series of laboratory tests,including one-dimensional compression creep tests（CCT） and triaxial creep tests（TCT） have been conducted;and creep deformation characteristics of Boom Clay are researched under different pressures and different types of experiments. A separated yield surface creep constitutive model implicit time in formula with irreversible strain variable is established after theoretical analysis. It can avoid the difficulty of determining the creep times when resolving the actual calculation under complicated working condition by the traditional model with explicit time. Finally,the numerical implementation of the new creep constitutive model is implemented;and the creep test on Belgian Boom clay is simulated. The results show that the new constitutive model and the UMAT subroutine in ABAQUS have good calculation accuracy and good stability,which could effectively depict the nonlinear creep characteristic of Belgian Boom Clay.