Constitutive model of anchorage interface and its application on timeliness analysis in underground engineering

Abstract

The creep property of anchorage interface is one of most important problems in analysing time effect of anchorage in underground engineering. In this paper, aiming at the defects of hard contact formulation in normal direction and discontinuity from bond to slip in tangential direction at anchorage interface when studying on the anchoring mechanism, a contact formulation which is an exponential softened pressure–overclosure relationship in normal direction and a continuous non‐linear constitutive model in tangential direction are proposed. The model solves the problem of converging difficultly and reflects the whole process of shear creep behaviour truly and reasonably because of its consideration of normal stress. By the further development of ABAQUS, the non‐linear creep model of anchorage interface is applied to analyse time effect of anchorage engineering. The main achievements are conducted as follows: anchor stress will increase with creeping effect of anchorage interface, and the location of anchorage peak stress will change and move towards the far end of anchor with the lapse of time. This paper provides the theory basis for deeply researching the reliability of anchorage in underground engineering.

Keywords:

• Tunnel
• Anchorage interface
• Constitutive model
• timeliness

This research work is financially supported by the National Natural Science Foundation of China (nos. 50720135906, 51009133 and 40772184).