Effects of fillet weld to large-size stud shear connector in full-depth precast bridge deck panel

Abstract

Resistance of large size headed stud shear connectors 31.8 mm (1¼″) diameter for full-depth precast concrete bridge deck panel with steel girders depends on various factors. One important factor is the weld connection between studs and a steel girder. This research presents two main welding effects: (1) beveling shape of the base stud and (2) layers of fillet weld, which could result to effective composite actions. Three groups of specimens were tested varying among three different beveling sizes, and 2 or 3-layer of fillet weld. The first group (S1-N0) contains studs without beveling, the second (S2-N5) and third (S3-N10) groups consist of studs with 5 mm and 10 mm bevel cut widths in 45-degree, respectively. Each was subjected to shear force from the hydraulic jack until failure or bending limit. The studs in S2-N5, both 2 and 3-layer of fillet weld, could obtain maximum shear resistance up to 56.8 kN (5.8 Ton-force). The large relative displacement (up to 56 mm) was carried on the studs in S1-N0 in both 2 and 3-layer of fillet weld. The stiffness (Load/displacement ratio) of the S3-N10 group were about 5% higher than those without beveling in the S1-N0 and S2-N5 group, which were about 3.56 kN/mm (0.4 Ton-force/mm). In terms of failure mode, tearing out at the bottom of the shank studs was appeared in some samples in the S2-N5 and S3-N10 groups, but in the S1-N0 group.