Shear behaviour and load capacity of short reinforced concrete beams exposed to chloride environment

Abstract

The effect of corrosion of reinforcement on the behaviour of deep, reinforced concrete beams was investigated. Long-term corrosion (27 years) in an accelerated climate process using a chloride environment close to natural corrosion resulted in a high level of heterogeneous loss of cross section on both longitudinal reinforcement and transversal reinforcement (stirrups). Control beams of the same age kept in a non-aggressive environment were also tested as controls. Tension reinforcement did not have special anchorage since the rebars had straight edges. For deep beams, the behaviour during bending tests involved a combination of arch action and beam action, which could be affected by corrosion in different ways, such as anchoring capacity, stirrup corrosion and resulting transversal cracks and loss of cross section in the tension reinforcement. Nevertheless, and despite the high corrosion level of the steel bars, the ultimate capacity of deep beams was only slightly decreased. The changes in load transfer mechanism and failure mode could explain these results.

Effect of different material constitutive models in estimating the residual moment capacity of RC beams subjected to natural corrosion

“…The 19 RC beams were taken from 13 different collaborative groups who were involved in the project (Castel et al. , 2000; Dang et al. , 2016; Dang and François, 2014; François et al.…”

“…The data from Laboratoire des Mat eriaux et Durabilit e des Constructions (LMDC) were obtained from a long-term experimental program that started in 1984 in Toulouse, France. The 19 RC beams were taken from 13 different collaborative groups who were involved in the project (Castel et al, 2000;Dang et al, 2016;Dang and François, 2014;François et al, 2013;Khan et al, 2012Khan et al, , 2014Kreit et al, 2011;Vidal et al, 2007;Yu et al, 2015;Zhang et al, 2009;Zhu et al, 2013Zhu et al, , 2015Zhu and François, 2016). The beams have undergone a series of continuous spraying and wetting-drying cycles for 3-27 years before subjecting them to a three-point loading system.…”

A FEM-based model to study the behaviour of corroded RC beams shear-repaired by NSM CFRP rods technique

“…The four tested RC beams were compared to other two beams; one is corroded A2CL2-A and the other is control tested by Dang et al (31), Figure 5 shows the load-deflection curves for all short beams tested experimentally. The shear strengthening increased the shear capacity for the control beams, while the response of the corroded beams due to shear strengthening depends on the pattern and the intensity of steel corrosion.…”

“…Load-deflection curves for all beamsThe difference in the yielding capacity of the shear repaired control beam A1T-SB and the shear repaired corroded beam A1CL3-SB refers to the 12% loss in cross section found at the middle of the corroded beam A1CL3-SB (the load-induced crack occurs at mid-span), while the decrease in the yielding capacity for non-shear repaired corroded beam A2CL2-A in comparison with non-shear repaired beams (Control, A1T-B and A1CL3-B) refers to the 10% loss in cross section found at the edge of the corroded beam A2CL2-A (the same edge of diagonal shear crack)(31).Experimental results showed also that shear strengthening with NSM CFRP rods technique changed the mode of failure from diagonal crack failure close to support due to slipping of tensile re-bars at anchorage (for non-shear-repaired beams A1T-B and A1CL3-B), to large flexural crack at mid span followed by concrete crushing (for shear-repaired beams A1T-SB and A1CL3-SB) as shown infigure 6. Experimental modes of failure for all tested beams It is also noteworthy that for shear-repaired beams A1T-SB and A1CL3-SB, many splitting cracks occurred at the mid-way of the beam's width as shown in figure 7 , these splitting cracks were clear to notice at the bottom of the beam and at the beams edges near the supports.…”

Effects of Corrosion on Compressive Arch Action and Catenary Action of RC Frames to Resist Progressive Collapse Based on Numerical Analysis

“…It has also been observed that corrosion of stirrups leads to the degradation of confined performance of core concrete [38]. Many studies have shown that the contribution of corrosion stirrups to the bearing capacity and ductility of beams [39][40][41] or columns [42][43][44] is reduced due to the corroded stirrups, which fails in confining the core concrete. Therefore, the weakening effect of confinement to the core concrete due to corroded stirrups should also be considered in numerical simulation [37].…”