Advanced computational methods versus analytical and empirical solutions for determining restraint stresses in bottom-restrained walls

The distribution of restraint stresses in bottom-restrained walls is a desired information for the efficient design of wall-like concrete members which are eccentrically restrained at the bottom of the wall. Practical examples are retaining walls, bridge abutment walls or tank walls, for which the results can be used in order to assess the risk and intensity of harmful separating cracks over the wall height.
Different solutions exist for the determination of these stress distributions, ranging from advanced computational methods over analytical and semi-analytical solutions up to empirical approaches. Advanced computational methods are mainly used in science or for rather complex tasks, whereas standard tasks in practice were preferably designed with analytical or semi-analytical solutions. The approaches given in guidelines and regulations are primarily based on analytical and semi-analytical solutions which are sometimes combined with empiricism, in order to represent the practical observation accordingly.
The aim of the present contribution is twofold. On the one hand, the general applicability as well as commonalities and differences of the investigated solutions were demonstrated by using them for the analysis of the same design task. On the other hand, a parametric study was carried out in order to assess the dependence of their prediction quality on changing geometrical conditions.
Altogether it was found that advanced computational methods and analytical or semi-analytical solutions showed a good agreement for common design tasks. Solutions with empirical modifications, however, were proved to be less satisfying from engineering perspective due to predefined parameters or mechanically inconsistent modifications. On the contrary, thermomechanical 3D modelling is recommended for all cases with a pronounced sensitivity against eigenstresses. Overall, this contribution may serve as a decision guidance to choose the suitable solution for a specific design task as well as a basis for the discussion on possible disagreements between different solutions.