Block shear strength in thin-walled lean duplex stainless steel fillet welded connection with base metal fracture

Effects of material property and thickness on block shear strength in lean duplex stainless steel welded connections

“…From aforementioned finding, this study recommended equation (8) using Mises yield criterion. In addition, as a series of parametric study, for 3.0 mm thick welded connection of material properties same with 1.5 mm thick lean duplex stainless steel plate, it was also confirmed that the average effective tensile stress distribution in the critical tensile section of block shear was close to 1.25 times the material tensile strength (Fu) due to the stress triaxiality by higher constraint effect of thickness direction (Cho et al, 2022a). However, it can be noted that the effective tensile stress factor may be different from 1.25 presented in equations (4) and (5) because the material tensile strength (Fu) and tensile strength-yield stress ratio (Fu/Fy) of the 3.0 mm thick duplex stainless steel in this study are different from those of 1.5 mm thick one.…”

“…Welded connections were planned to fail by base metal not weld metal or heat affected zone referring to literature (Ke et al, 2018d). In order to investigate the block shear rupture strength of the base metal rather than the welded metal part in the weld connections of cold-formed lean duplex stainless steel (STS329FLD in Korean Industrial Standards (KS) (2015c), corresponding to ASTM UNS S32101 and EN 1.4162), a material tensile test has been performed by Cho et al (2021b; 2022a). To ensure the reliability of experimental results, two specimens for each series were manufactured and tested.…”

“…Thus, the prediction accuracy of the base metal block shear fracture strength of the lean duplex stainless steel by recommended equations considering material tensile strength difference and stress triaxiality effect is improved. In near future, based on the experimental results and the developed analysis results by authors (Cho et al, 2021b, 2022a), it is required to reconfirm the tensile stress and shear stress factor at the block shear critical section discussed in this study and to verify the validity of the recommended block shear strength equation, performing additional parametric analysis according to the difference in plate thickness and material strength except those treated here.…”

“…This study focused on the base metal block shear fracture of lean duplex stainless steel (STS329FLD) welded connections with different plate thickness and test material properties. Experimental and numerical studies on the lean duplex stainless steel (STS329FLD) welded connections (SD1.5 series specimens) with 1.5 mm thick plate and base metal block shear have been conducted by authors (Cho et al, 2022a). As a result.…”

“…Experimental and numerical studies on single-shear and double-shear bolted connections with two and four bolts made of cold-formed lean duplex stainless steel (STS329FLD) simple tensile tests have been performed (Kim et al 2020b, 2021f). Welded connections of base material block shear fracture made of cold-formed duplex stainless steel with 1.5 mm (Cho et al, 2022a) and 3.0 mm (Cho et al, 2021b) thick plates produced in Korea were tested under monotonic tensile loading and finite element analysis model including ductile damage simulation using nonlinear analysis software, ABAQUS was established. Two papers recommended the block shear equations of lean duplex stainless steel welded connection with base metal fractures, respectively for 1.5 mm and 3.0 mm thick specimens.…”