Experimental investigation on a non-seismic precast RC beam-column exterior joint under quasi-static lateral cyclic loading

Abstract

Beam-column joints were detected as the weakest link in existing RC momentresisting frames. The failure of beam-column joints, especially the exterior joint in a precast RC building commenced the collapse of the whole structure. Precast RC beam-column joints which were not designed in accordance with the seismic Code of Practice worsen the damage when subjected to seismic loading. This paper presents experimental work on a full-scale precast RC beam-column exterior joint with corbels when subjected to quasi-static lateral cyclic loading. The specimen was tested under reversible lateral cyclic loading up to a ±1.0% drift. Two numbers of cycles were applied for each drift level. Cracks, gap opening and closing, and spalling of concrete were monitored in successive twocycle intervals of drift. The experimental observation showed that the cracks start to occur at +0.3% drifts and no damage was observed at the corbels. At ±1.0% drift, the specimen experienced major damage at the column above the joint and also at the monolithic cast-in-place area. The specimen exhibits a captive column damaged because of the weak column-strong beam condition of the specimen. Poor detailing of reinforcement and link spacing led to unconfined concrete inside the column. The wide link spacing measured as 190 mm centre-to-centre was unable to cater for a larger load, especially lateral loading from an earthquake. In this study, it can be concluded that a precast beam-column exterior joint experienced severe damage if not designed in accordance with the seismic Code of Practice. The stiffness degradation, displacement ductility and equivalent viscous damping for the tested specimen are also discussed in this paper.

Behavior of RC Eccentric Corner Beam-Column Joint under Cyclic Loading: An Experimental Work

“…The yield displacement definition of experimental work is considered according to Ghani and Hamid [14] as shown in Figure 14. It was considered as the most practical definition for the yield displacement for the reinforced concrete structures.…”

Seismic Performance of Interior Beam-Column Joint With Fuse-Bar Designed Using Ec8 Under In-Plane Lateral Cyclic Loading

“…Previous research had highlighted that most of the RC structures components which have been designed such as beam-column joint with corbel, wall-slab connection, tunnel form building and precast shear-key wall performed poorly under in-plane lateral cyclic loading [1,2,3,4]. In order to improve the performance of beam-column joint in RC moment-resisting frames, fuse-bars which acting as energy dissipater will be installed inside the beam-column joint.…”

“…Most of existing RC buildings in Malaysia were designed in accordance to British Standard (BS 8110) which did not have any provision and guidelines for earthquake loading at all. Experimental works had been conducted for tunnel form building [1], non-seismic precast RC beam-column joint [2], wall-slab joints of Industrialized Building System (IBS) [3] and precast shear-key wall panel [4] which designed according to BS8110. The experimental results showed that the structural components performed poorly under in-plane and out-of-plane loading with low ductility.…”

Seismic Behavior of Tunnel Form Building under Lateral Cyclic Loading

“…Layssi has studied the poor seismic response of shear walls and then repaired and retrofitted damaged walls using CFRP fabrics [11][12][13]. Others studies on shear walls and precast walls have been conducted in order to determine the seismic behavior of low-ductility precast walls under in-plane lateral cyclic loading [14][15][16][17]. Recently, strengthening techniques for non-ductile reinforced concrete shear walls using externally bonded CFRP sheets under in-plane seismic loading have been investigated [18,19].…”