Linwei He

Automatic yield-line analysis of slabs using discontinuity layout optimization.

The yield-line method of analysis is a long established and extremely effective means of estimating the maximum load sustainable by a slab or plate. However, although numerous attempts to automate the process of directly identifying the critical pattern of yield-lines have been made over the past few decades, to date none has proved capable of reliably analysing slabs of arbitrary geometry. Here, it is demonstrated that the discontinuity layout optimization (DLO) procedure can successfully be applied to such problems. The procedure involves discretization of the problem using nodes inter-connected by potential yield-line discontinuities, with the critical layout of these then identified using linear programming. The procedure is applied to various benchmark problems, demonstrating that highly accurate solutions can be obtained, and showing that DLO provides a truly systematic means of directly and reliably automatically identifying yield-line patterns. Finally, since the critical yield-line patterns for many problems are found to be quite complex in form, a means of automatically simplifying these is presented.

Automatic Yield-Line Analysis of Practical Slab Configurations via Discontinuity Layout Optimization

AbstractThe yield-line method provides a powerful means of rapidly estimating the ultimate load that can be carried by a reinforced concrete slab. The method can reveal hidden reserves of strength ...

Human-in-the-Loop Layout and Geometry Optimization of Structures and Components

Numerical truss layout optimization employs a ground structure which comprises a large number of potential structural elements from which an optimal subset is sought. The basic problem formulation can be solved via linear programming, which means that very large problems can be solved quickly. However, although layout optimization has been found to provide a highly effective means of identifying (near-)optimal truss layouts, these can be overly complex in form and hence unsuitable for practical use. To address this, a range of practical considerations can potentially be incorporated in layout optimization formulations directly (e.g. via the inclusion of nonlinear and/or nonsmooth terms). However, this will often greatly increase computational cost. Also, some practically important constraints are difficult to specify mathematically (e.g. aesthetic considerations). Furthermore, rather than being presented with a single ‘optimal’ design, designers often seek more flexible tools that allow them to interactively modify a design for a wide range of reasons.