【摘要】 研究目的:隧道数值模拟的应用已相当广泛,在数值建模过程中,如何从实际问题中提取出合理的边界范围,平衡计算精度和占用内存之间关系,选取较佳的结合点,是数值建模中重要的部分。文章结合某隧道的工程实际,从数值模拟分析的角度,分两倍洞跨、三倍洞跨、五倍洞跨和八倍洞跨四种围岩边界范围进行了数值模拟。通过比较其第一主应力、位移和塑性区等结果,提出一般情况下隧道围岩模型的边界范围取值。研究结论:不同边界范围对隧道其周围的应力场和位移场的分布影响不大;一般情况下,取3倍洞距边界范围对隧道进行数值模拟和结构设计,其分析结果和结构设计方案较为安全。更多还原

【Abstract】 Research purposes: The numerical simulation of tunnel has been widely used.In the numerical simulation process,how to choose the reasonable boundaries for the project and how to balance the relationship between the calculation precision and the occupation of the internal memory of the computer and how to choose the perfect combined pont are the important parts in the modeling for tunnel.This paper presents the four kinds of the numerical simulations of the two times tunnel span,three times tunnel span,five times tunnel span and eight times tunnel span for choosing the boundary range.The general boundary range of the surrounding rock model is offered based on the comparison of results of the first principal stress,displacement and plastic zone. Research conclusions:It is shown that the effect of different boundary ranges of tunnel on the surrounding stress field and displacement field can be ignored in simulation.It is also suggested that the boundary range of the three times tunnel is used for the numerical simulation and structure design,and it can get good analysis result and safe structure design.更多还原