盾构隧道与地层相互作用的模型试验设计

Scaled Model Test Design for Interaction between Shield Tunnel and Stratum

设计缩尺模型时,应使影响试验测试结果的主要因素满足相似关系,次要影响因素可以不满足相似关系,以最大限度地减小模型试验误差。当模型盾构隧道材料的弹性模量无法满足相似关系时,可以调整模型隧道的内径和管片厚度,使模型隧道横断面曲梁在相似的弯矩作用下产生相似的转角,以此作为管片厚度设计要求;模型隧道材料的密度可以不满足相似关系。开槽模型管片纵缝接头的转动刚度可控性良好,建议用于模型盾构隧道管片环。模型土的黏聚力与内摩擦角可以不满足相似关系;模型土的压缩模量与实际土体的压缩模量应保持相似关系,模型土取压应力(100/Cσ)kPa到(200/Cσ)kPa时对应的压缩模量。

In order to minimize model test error,during the design of a scale model,the major factors that affect the scale model test results should meet the similarity relationship,and the minor influence factors may not necessarily meet the similarity relationship.When the elasticity modulus of the model shield tunnel mate-rial is unable to meet the similarity relationship,the inner diameter and the thickness of the model shield tunnel segment can be adjusted to cause the cross-section curved beam of the model shield tunnel to generate a similar rotational angle under similar bending moment as the segment thickness design requirement.Besides,the density of the model shield tunnel material may not necessarily meet the similarity relationship.The rotational stiffness of the longitudinal joints of the grooved model segments demonstrates good controllability.The grooved model segment longitudinal joint is suggested to be used in model shield tunnel segment ring.The cohesive force and angle of internal friction of model soil may not necessarily meet the similarity relationship.However,the compression modulus of model soil and the compression modulus of the actual soil should maintain a similarity relationship.The test pressure of compression modulus of model soil is from（100/Cσ）kPa to（200/Cσ）kPa.