温州深厚软黏土流变模型识别及工程应用分析

Identification on Rheological Model for Thick Soft Clay in Wenzhou and Relevant Engineering Application

深厚软黏土隧道在运营期间的长期稳定性是困扰隧道安全运营的重要难题.本文以温州某区段深厚软土为研究对象,在理论分析的基础上,建殳了温州深厚软黏土的弹粘塑性本构模型。通过加拿大Sackville地区软黏土、温州软黏土和日本大阪软黏土的流变试验的试验数据,验证了模型的可靠性。通过流变试验数据与弹粘塑性本构模型的拟合曲线进行对比,发现建殳的本构模型能够很好地反映这三种软黏土的流变性能,采用此本构模型能够很好地描述软黏土的流变特性。最终以ABAQUS为平台,开发UMAT子程序——EVPMCC,建立深厚软土盾构隧道的有限元计算模型,对深厚软土盾构隧道的长期变形规律进行数值模拟研究,探讨了软黏土流变性长期变形的影响规律。本研究可以为深厚软土盾构隧道的设计、施工、监测、运营提供一定的理论依据。

The long-term stability of the thick soft clay tunnel is an important problem for the safe operation. In this paper, thick soft soil in wenzhou was selected as an object of research. On the basis of theoretical analysis, the elastic viscoplastic constitutive model of thick soft clay in Wenzhou was established. The reliability of the model was verified by rheological tests of the soft clay in the Sackville area of Canada, Wenzhou and Osaka in Japan. Through the comparison between the rheological test data and the fitting curve of the elastic-viscoplastic constitutive model, it was found that the constitutive model established could reflect the rheological properties of these three kinds of soft clay very well. Finally, ABAQUS was used as the platform to develop the UMAT subroutine, EVPMCC. The finite element model of thick soft clay shield tunnel was established by using EVPMCC, and the long-tenn deformation law on rheological properties of soft clay was studied. This study could provide a theoretical basis for design, construction, monitoring and operation of thick soft clay shield tunnel.