A Review of Numerical Methods for the Analysis and Design of Soft Ground Tunnels

摘要

The last two decades have witnessed a steady fall in the cost of digital computers and also an increase in computing power (both speed and storage) of the machines available. A parallel development has taken place in the application of numerical methods (using those same computers) to all branches of engineering. The scope of this review is the degree of success that can be expected when various numerical methods are applied to problems associated with soft ground tunnelling. The view taken here of what constitutes a numerical method is rather wider than the view likely to be taken by a numerical analyst or computer scientist. For the purposes of this review any method of analysis which is made more convenient by the use of a digital computer is a numerical method. Thus the review discusses some methods which are analytical rather than numerical. The first reason for this is (as has just been suggested) a computer would be used to tabulate numerical results from some analytical solution (e.g. obtained via the theory of elasticity). The second reason is related to a particular view of numerical modelling: the results of such analysis should lead to a simpler view of the problem. Although a numerical model may contain an elaborate set of assumptions the engineer should examine the results to determine the dominant physical processes and hopefully a simpler (analytical) model of the situation.