Search results for "Welded joint"
showing 8 items of 8 documents
Experimental test results vs. analytical prediction of welded joint strength in hybrid steel trussed concrete beams (HSTCBs)
2013
The aim of the paper is to provide practical guidelines for the design of welded joints of steel truss for encased composite steel–concrete beams. The results of experimental tests are presented and interpreted. The steel truss is made of a steel plate acting as the bottom chord, made of S355 structural steel, coupled with steel rebars which form the upper chord, and steel inclined web rebars (V-reverse) welded to the two chord elements, both of them made of steel B450C. Butt welded joints of web bar to bottom steel plate and fillet welding joints of inclined web bars to top chord bars were tested, as they are different from the ones which are normally used due to the coupling of different …
Re-analysis of fatigue data for welded joints using the notch stress approach
2010
Abstract Experimental fatigue data for welded joints have been collected and subjected to re-analysis using the notch stress approach according to IIW recommendations. This leads to an overview regarding the reliability of the approach, based on a large number of results (767 specimens). Evidently, there are some limitations in the approach regarding mild notch joints, such as butt joints, which can be assessed non-conservatively. In order to alleviate this problem, an increased minimum notch factor of Kw ⩾ 2.0 is suggested instead of the current recommendation of Kw ⩾ 1.6. The data for most fillet-welded joints agree quite well with the FAT 225 curve; however a reduction to FAT 200 is sugg…
Fatigue Design of Cruciform Joints including V-notch Effect at the Weld Toe
2014
Abstract The present paper proposes a new and more accurate fatigue life prediction model for fillet welded joints in steel subjected to constant amplitude loading. With the traditional fracture mechanics approach, the greatest difficulty when computing the fatigue life of a welded detail is to determine the initial crack size a0. The classical way to determine the stress intensity factor K (SIF) is by using the following formula Where σ is the applied stress, a is the crack size and g(a/T) the geometrical correction factor which has been determined by Gurney function or similar solutions. This approach is not accurate for short crack because of the singular V-notch behaviour close to the c…
Defect characterization in Al welded joints by non-contact Lamb wave technique
2006
Abstract The use of air-coupled sensors to detect flaws in Al welded joints and the advantage of Lamb wave for their characterization has been proved. Ultrasonic waves were generated by a pulsed laser and by contact angle-beam transducer, and received by an air-coupled capacitive transducer. Laser-based configuration was used to quickly locate the defect, whereas the angle-beam contact probe configuration to characterize it thanks to the dispersive behavior of Lamb waves. Guided waves allow inspection of the complete thickness with only one scan, permitting to detect and to size both internal and surface defects; their high flexibility in the measurement is due to the various parameters cha…
Indagine sperimentale su nodi di tralicci in acciaio di travi reticolari miste
2009
Results of experimental tests on welded joints of steel truss of encased composite steel-concrete beams are presented. The welding of the inclined web bars to top bars, both of steel type B450C, and to bottom steel plate, the latter made of S355 steel type, are tested. Two analytical expressions for prediction of welding strength are derived: the one based on a resistance criterion and the other based on a limit domain of the welding section. Guidelines for choosing the effective dimensions of the fillet weld, necessary to determine the strength, are provided. A high precision digital scanner is used to validate the suggested guidelines to determine the geometrical characteristics of the fi…
Travi reticolari miste- Problemi locali nella trasmissione degli sforzi
2009
Experimental test results on the local behavior of the typical Italian typology of hybrid steel-to-concrete beam are presented and discussed in order to provide insight on transfer mechanism between different components of the beam. Preliminarily, in order to investigate on the bearing capacity of the welding and on the local instability problems that can arise in the trusses before concrete casting, tensile tests on specimens reproducing different types of welded joints, and push-out tests on bare specimen have been performed. Then, the transfer mechanism between steel trusses and concrete is investigated by means of push-out tests carried out also in displacement controlled mode. Results …
Stress transfer mechanism investigation in hybrid steel trussed-concrete beams by push-out tests
2014
Abstract Results of push-out tests carried out on Hybrid Steel Trussed–Concrete Beams (HSTCBs) before and after the concrete casting are presented and interpreted. Firstly, in order to check the ability of weldings before casting, tensile tests were performed on specimens reproducing different types of welded joints. Simplified design formulae were used to predict their ultimate strength. Secondly, results obtained by push-out tests on specimen representative of the beam before and after the concrete casting are presented and discussed. Finally, simplified analytical models proposed by the current European building code were adapted to the specific typology to roughly predict the ultimate s…
Optimizing the Shape of Welded Constructions Made through the Technique “Temper Bead Welding”
2020
Welded constructions are subject to high stresses during operation. One solution for improving the behavior in exploitation of welded constructions in various cases is to use the welding technique “temper bead welding” (TBW). In the paper, the optimization of the geometry of the welded joints by the TBW technique was performed. Thus, corner welded joints made of S355 steel were analyzed. To make the welded joints, three layers of welding seams were deposited, and the intermediate layers were processed through cutting with various radii. To analyze the influence of the size of these rays on the behavior of welded constructions, a research program based on factorial experiences wa…