Coupled Modeling Of Tunnel Face Stability Using Desai’s Theory And TFA
Price
Free (open access)
Transaction
Volume
41
Pages
10
Published
2005
Size
676 kb
Paper DOI
10.2495/CMEM050381
Copyright
WIT Press
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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