Abstract: The discontinuity layout optimization is a novel numerical method for upper bound limit analyses, proposed in 2007. It is widely used in analyzing the limit load and stability of geotechnical and plate/shell-like structures. In this method, a large number of nodes are introduced into the domain, the lines(2D)and surfaces(3D)formed by the nodes are considered as potential discontinuities. Based on the minimization of dissipated energy, the target function is built. The restraints equations are generated by geometric compatibility conditions, Mohr-Coulomb flow rules, and load/work conditions. Not only the limit load/factor of safety but also the activated discontinuities and displacement jumps are obtained. The method is theoretically clear, whose pre- and post-processing is easy for implementing and its computational efficiency is very high. However, there are only a few researches and applications about this method in China. This work is the first Chinese paper introducing DLO, which presents basic concepts, engineering applications especially in geotechnical and tunneling engineering of this method in details, which will hopefully promote its further developments in China.
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2019, Vol. 1 
