Reliability-based resistance of RC element subjected to membrane action and their sensitivity to uncertainties. (1st July 2021)

• Record Type: Journal Article
• Authors: Botte, Wouter; Droogné, Didier; Caspeele, Robby
• Is Part Of: Engineering structures. Volume 238(2021)
• Publication Date: 2021-07-01
• Subjects: Reinforced concrete -- Membrane action -- Sensitivity analysis -- Design resistance; Structural engineering -- Periodicals; Structural analysis (Engineering) -- Periodicals; Construction, Technique de la -- Périodiques; Génie parasismique -- Périodiques; Pression du vent -- Périodiques; Earthquake engineering; Structural engineering; Wind-pressure; Periodicals; 624.105
• DOI: 10.1016/j.engstruct.2021.112259
• Languages: English
• ISSNs: 0141-0296

Abstract

Highlights: Three different types of RC elements subjected to membrane action are investigated. Resistances are determined by variables not involved in traditional design. Resistance in case of multiple failure modes based on mixed-lognormal distribution. ECOV and lognormal distribution provide good results in case of one failure mode. Abstract: Traditional design of reinforced concrete structures is usually based on small deformation theories whereas in order to assess the ultimate load bearing capacity of RC structures against progressive collapse significant deformations should be taken into account. The alternate load paths facilitated by membrane action which develop under large deformation can activate a significant strength reserve, redistribute the loads and hence limit the damage progression in the structure. Up to date, no uniform approach is available on how to incorporate these membrane effects in the structural design or verification procedures against progressive collapse. In this article, sensitivity analyses were performed to investigate the effect of the stochastic nature of membrane action on the load bearing capacity for three distinct RC elements, i.e. a beam, one-way slab and two-way slab. It was found that variables which are usually not explicitly taken into account by traditional design methods, such as the axial restraint stiffness and ultimate reinforcement strain have a significant influence on the resistance of the considered elements. Subsequently, the design resistance of the elements was assessed using a probabilistic method and the ECOV method. It was found that the ECOV method and the probabilistic method considering a lognormal distribution provide similar results in case one observes a single failure mode for which the variability of the resistance is limited. In case of multiple failure modes and a large variability of the resistance, a mixed lognormal distribution proved to enable a more accurate design resistance estimation.