WIT Press


Coupled Modeling Of Tunnel Face Stability Using Desai’s Theory And TFA

Price

Free (open access)

Paper DOI

10.2495/CMEM050381

Volume

41

Pages

10

Published

2005

Size

676 kb

Author(s)

J. Trčková & P. Procházka

Abstract

Coupled modeling of the behavior of structures (mutual comparison of experimental and numerical models) becomes a very powerful tool for assessment and design. In this paper we concentrate on the assessment of the tunnel face from an experimental and numerical point of view. The experiments start with scale modeling from physically equivalent materials, while the numerical method involves the finite element method with the constitutive law by Desai and transformation field analysis serves as a tool for improvement of the numerical model, which should soon be close to reality. 1 Introduction In this paper, coupled modeling based on a comparison of numerical models and experimental scale modeling is put forward. Possible time dependent behavior, creep for example, can be accurately obtained from the coupled modeling. The scale models are prepared from physically equivalent materials, while for numerical modeling classical 24 nodal point degrees of freedom finite elements are used. The comparative approach consists in the following idea. First, select subdomains with uniform distribution of eigenparameters, see [1], for example. Theoretically one can select as many subdomains as nodal points used in the computation. But in this case the calculation can exceed reasonable computational time and from the nature of the problem the subdomains can be estimated in advance to lower the number of free eigenparameters. Then, one can write the overall stress as a linear hull of stresses due to external load in a purely linear elastic medium and uniformly distributed eigenparameters in subdomains,

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