Experimental study on seismic performance of post-fire reinforced concrete frames

Abstract

To investigate the post-fire seismic behaviour of reinforced concrete (RC) frames with different columnto-beam bending capacity ratios, four specimens were fabricated, which included a strong-beam-weakcolumn frame and a strong-column-weak-beam frame either under room temperature or after being exposed to fire. The fire test was conducted in a furnace chamber, followed by quasi-static tests under a low-frequency cyclic load. The crack patterns, hysteretic loops, plastic hinges, and failure modes were investigated in the loading process. The influence of two factors, i.e., the fire exposure and the columnto-beam bending capacity ratio, on the mechanical performance, ductility, stiffness degradation, and energy dissipation was compared and analysed. The experimental results indicated that the ultimate bearing capacity, the stiffness, the ductility factor, and the energy dissipation capacity of the RC frames decreased after fire exposure. The bearing capacity of the strong-beam-weak-column frame decreased even more seriously. Although the yielding displacements of the post-fire frames increased, their ultimate displacements decreased. In addition, the strong-column-weak-beam frame under room temperature failed in the form of beam-end plastic hinging, while after being exposed to fire, the failure mode changed to shear-bond failure in column.

Repair of Fire-Damaged Reinforced Concrete Flexural Members: A Review

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Experimental Study on Seismic Strengthening of Confined Masonry Walls Using RPC

“…e low cyclic reversed loading test was a widely accepted method to assess the seismic performance of structural members, such as frames, shear walls, and masonry walls [16,33,34]. e specimens were tested in the Disaster Prevention and Mitigation Laboratory of Shandong Jianzhu University, China.…”

C-FRCM Jacket Confinement for RC Columns under Impressed Current Cathodic Protection

“…Concrete is the most widely used building material in the world. However, reinforced concrete (RC) structures might face durability problems (Zhang et al 2017a;Li et al 2019), most of which are caused by the corrosion of steel rebars induced by chloride ions (Mehta 1991). The influence of steel corrosion on an RC structure has the following aspects: First, rusting causes the steel volume to expand, causing the concrete to crack (Rodriguez et al 1994); Second, when a rebar is corroded, the cross-sectional area of the rebar is reduced (Ahmad 2003); Third, the bonding performance of rebar and concrete is decreased by the corrosion (Fang et al 2006).…”