Modeling and design of concrete hinges under general loading

Abstract

Despite their successful applications in practice for over a century, the design of concrete hinges still entails considerable modeling uncertainty. Their dimensioning still relies on semi‐empirical recommendations originally proposed for admissible stress design, based on limited experimental data and generalized with engineering judgment. This presumably results in overly conservative designs in many cases, particularly when applied with modern design codes based on partial safety factors. This paper addresses these issues by revisiting the analytical modeling for one‐way Freyssinet concrete hinges under general loading based on approaches compatible with current design codes. A cross‐sectional analysis with confined concrete properties is proposed for the behavior under axial forces and bending moments, where the strength of the triaxially compressed concrete in the hinge throat is determined with a discontinuous stress field. The hinge resistance to shear forces is investigated with failure mechanisms inspired by failure modes observed in experiments. Based on the shear strength, a simple approach to estimate the torsional resistance of the throat is proposed. Remarks are also made on the analysis of combined actions. The predictions of the proposed models are validated against a wide range of test data, including a series of recently conducted own experiments. Overall, the proposed models agree better with the available experimental data than the existing approaches, potentially allowing for a more efficient design of new and assessment of existing concrete hinges.

Large‐scale experiments on concrete hinges under general loading

“…A comprehensive comparison with experimental data from the literature and current and newly-developed analytical models is presented in a follow-up paper. 23 • cemsuisse, the association of the Swiss cement producers, for partially funding this work (project number 201703).…”

“…A comprehensive comparison with experimental data from the literature and current and newly‐developed analytical models is presented in a follow‐up paper 23 …”

“…In the following sections, the experiential campaign is described in detail, the obtained results are presented and discussed, and the findings are finally summarized in the conclusions. The authors are currently establishing mechanical models for the observed behavior, which are compared to the experimental data and current design rules in a separate publication 23 . The experimental and theoretical outcomes resulting from this research project will not only improve the understanding and modeling of concrete hinges, but also of other related structural members such as longitudinal joints between segmental tunnel linings 24 …”