Effects of shear connectors on plate-reinforced composite coupling beams of short and medium-length spans

Abstract

Experimental studies on the newly proposed design of plate-reinforced composite (PRC) coupling beams have been carried out. Previous results have demonstrated the useful application of this design in coupling beams of medium span-to-depth ratios (l/ h) under both inelastic seismic and elastic wind loading. This paper presents further experimental studies on five PRC coupling beams, which investigated the importance of shear connectors on plate/reinforced concrete composite action. Three medium-length (l/ h = 2.5) and two short (l/ h = 1.17) PRC coupling beams, each containing a vertically embedded steel plate, were tested under reversed cyclic loading. While one short beam was welded with expanded metal meshes on the plate surfaces, others were welded with shear studs on the plates in the wall regions and/or the beam spans. Results showed that the expanded metal meshes did not work effectively, and while the shear studs in the beam span only slightly increased the beam capacity, those in the wall regions contributed considerably in improving inelastic beam performance.

A unified design approach for plate-reinforced composite coupling beams

“…The design procedure of PRC coupling beams described in this section is applicable to normal practical ranges of span/depth ratios (1 ≤ l/h ≤ 4) and plate depth/beam depth ratios (0.95 > h p /h > 0.8) which are in line with the previous experimental and parametric study [12][13][14][15][16].…”

“…The performance of deep PRC coupling beams was found to be comparable to that of diagonally reinforced coupling beams, while the former can be designed for large capacities by simply providing a thicker plate without facing the problem of steel congestion [15]. The shear studs in the wall regions contributed considerably in improving inelastic performance while those in the beam span could only slightly increase the beam capacity of PRC coupling beams [14]. To ensure desirable inelastic performance of PRC coupling beams, the embedded steel plate has to be effectively anchored in the wall piers by providing shear studs on the plate surfaces in the wall regions.…”

“…Eight half-scale PRC coupling beam specimens with span/depth ratios of 2.5 and 1.17, respectively, had been tested [12][13][14][15] to quantify the strength, deformability, energy dissipation, shear stud force distributions and internal plate forces. The excellent shear capacity, very good energy absorption and deformability of PRC coupling beams were demonstrated experimentally.…”

“…To ensure desirable inelastic performance of PRC coupling beams, the embedded steel plate has to be effectively anchored in the wall piers by providing shear studs on the plate surfaces in the wall regions. Design models of simplified bearing stress distribution in the plate anchorage were proposed [13,14]. Nearly one hundred non-linear finite element models of hypothetical PRC coupling beams with different ratios of clear span length to overall depth 1 ≤ l/h ≤ 4 and steel plate depth to overall beam depth 0.95 > h p /h > 0.8 were analyzed [16,17] behaviours of shear studs in the embedded beam region and in wall regions.…”

Deformability evaluation of high-strength reinforced concrete columns

“…In the past, numerous researchers have conducted cyclic reversed loading tests on RC columns to assess their seismic performance by displacement ductility factor (Ahn and Shin, 2007;Baczkowski and Kuang, 2008;Xiao et al, 2008;Youm et al, 2007) or displacement as well as curvature ductility factor (Bayrak and Sheikh, 1998;Ho and Pam, 2003a;2003b;Li et al, 1991;Watson and Park, 1994) which is the ratio of the ultimate to the yield value of the respective parameter. Some theoretical analyses were also carried out to investigate the flexural ductility of RC beams and columns (Bai et al, 2007;Bai and Au, 2009;Ho et al, 2003;Kwan et al, 2002;Lam et al, 2009;Su et al, 2006;. In addition to ultimate curvature and ultimate displacement, ultimate rotation of the member is also important in the design of earthquakeresistant structures.…”