Study on Load-Slip Characteristic Curves of Perfobond Shear Connectors in Hybrid Structures

Abstract

Load-slip characteristic of shear connectors is the basis of connectors' stiffness inputting in finite element analysis and load transfer study of shear connector groups. Based on three series and 24 groups large-scale experiments of perfobond strip shear connectors (PBL) and depended on the cutting-edge measurement techniques of distributed optical fiber sensors, mechanic characteristics and important influence factors were analyzed thoroughly, corresponding formula for ultimate bearing capacity of PBL connectors was suggested. Further load-slip characteristics under elastic limit and ultimate bearing state were induced, load-slip curve expression of PBL connectors under static complete loading was derived. The results show that the elastic limit load of PBL connectors in hybrid structures is about 0.35 times the ultimate bearing load, the yield load is about 0.7 times the ultimate bearing load. The complete load-slip curve of a PBL connector consists of a straight line branch in elastic phase and a curve branch following logarithmic distribution in nonlinear phase.

Flexural behavior of preloaded reinforced concrete beams strengthened by prestressed CFRP laminates

“…For groups R-b1r1d0 and RF-b1r1d0, with a 20 mm diameter steel rebar at the 21 mm diameter hole and almost no concrete dowel surrounding the rebar, the transverse rebar was also sheared off directly at the plate/concrete interfaces. For groups R-b0r1d1, R-b1r1d1, RF-b0r1d1, and RF-b1r1d1, with a 20 mm diameter rebar inside concrete dowel passing through the 60 mm diameter hole, the transverse rebar presented a tension/ shear failure mode, similar to PBL embedded in conventional concrete that were previously observed and reported by Wang et al [6], Su et al [8] and He et al [22]. Fig.…”

“…Meanwhile, PBLs in hybrid girders have much stronger interfacial restraints and the interfacial bond at the contact surface between perforated plate and concrete is more significant as compared with those in the superimposed beams [6]. As sufficient quantity of PBLs are used to transfer the major shear forces between steel components and concrete in hybrid girders, the effect of local concrete at the end of the perforated plate is small and can be negligible [7][8][9].…”

“…(18) was modified from Eq. (7) which was developed for the evaluation of PBL with conventional concrete in steel-concrete joints, the related experimental results obtained by the third parties Wang et al [6], He et al [7], Su et al [8], Zheng [21], and authors' previous research [22] were introduced to assess the applicability of Eq. (18) to PBL using conventional concrete in steel-concrete joint in hybrid girders.…”

“…Wang et al [6] performed twenty-four push-out tests to study the mechanical behavior of PBL in hybrid girders. It was shown that the interface bond between perforated plate and surrounding concrete substantially increased due to the strong restraints on the plate resulted from the reinforcements in concrete blocks.…”

Numerical Simulation Study on Shear Behavior of Hat-shaped Shear Connector

“…In China, Zhang, Z. H. [6], Wang, W. A. [7], He, S. H. [8] et al studied a large number of model tests and finite element studies on PBL shear connectors.…”