TIME-DEPENDENT TUNNEL CONVERGENCE .2. ADVANCE RATE AND TUNNEL SUPPORT INTERACTION

Abstract

A time-dependent model of tunnel convergence for tunnelling in a viscoelastic rock mass is proposed in the accompanying paper (this issue, pp. 469-475) to model the excavation-construction process during tunnelling in a rock mass with rheological properties. In this paper, a parametric study based on this model is presented to investigate the effects of the tunnelling advancing and support installation, respectively, on the tunnel convergence and on the support-pressure. Furthermore, a non-linear optimization procedure is suggested to calibrate the required model parameters from the in situ measured tunnel-convergence data. Discussion on the proper application of the proposed model and the optimization calibration are also included.