86,644 research outputs found
Notch stress intensity factors and fatigue behaviour of steel and aluminium welded joints
No full textWeld bead geometry cannot, by its very nature, be precisely defined. Parameters such as bead
shape and toe radius vary from joint to joint even in well-controlled manufacturing operations.
In the Notch Stress Intensity Factor (N-SIF) approach the weld toe region is modelled as a sharp
V-shaped corner and local stress distributions in planar problems can be expressed in closed
form on the basis of the relevant Mode I and Mode II N-SIFs. Initially thought of as parameters
suitable for quantifying only the crack initiation life, N-SIFs are shown able to predict also the
total fatigue life, at least when a large part of the life is spent as in the propagation of small
cracks in the highly stressed region close to the notch tip. A large amount of experimental data
reported in the literature for steel and aluminium welded joints is used here to demonstrate the
applicability of the N-SIF-based approach
Conceptual approach to the structural design of graduate theses in the Faculty of Architecture
No full textComplete trauma disruption of the left hepatic duct: endoscopic treatment after failure of surgical repair
No full textNo Abstract
EFFECT OF HOT-DIP GALVANIZATION ON THE FATIGUE BEHAVIOUR OF WELDED STRUCTURAL STEEL
No full textThis paper investigates the effect of a galvanizing coating on the fatigue strength of S355 structural steel. While in the literature some results from fatigue tests made on unnotched specimens can be found, very few results are available dealing with notched components and, at the best of authors’ knowledge, no results are available dealing with welded joints and bolted connections. The aim of the present paper is to partially fill this lack of knowledge. A comparison is carried out, between hot dip galvanized fillet welded cruciform joints made by S355 structural steel and not treated welded joints characterized by the same geometry, sub- jected to a load cycle = 0. In addition a large amount of bolted connections have been tested
Fatigue strength of welded joints: a synthesis based on generalised stress intensity factors and local strain energy
No full textFatigue Strength of Welded Joints: a Synthesis based on Generalised Stress Intensity Factor and Local Strain Energy
No full textFATIGUE TESTS ON RIVETED CONNECTIONS
No full textTo estimate the fatigue strength of riveted joints represents a problem of primary importance both for the re-analysis of old bridges and the assessment of relatively recent structures. Even if the riveted solution is going to be progressively substituted by bolted and welded solutions, the behaviour of riveted members remains a matter of considerable economic importance. Technical specifications available in the Standards in force give to engineers engaged in fatigue design problems a reference curve relating to only one detail and the recommended values appear to be very different. In particular, recent re-analysis reported in the literature showed that the value suggested by the Eurocode 3 for shear splices that use non pre-loaded high strength bolts is strongly non-conservative when applied to riveted connections taken from old bridges. The paper presents the results of fatigue tests carried out on 3 different riveted joints and compares them to the design curves reported by some European and American Standards in force
Fatigue behaviour of bonded anchors subjected to tensile loads
No full textFollowing recent studies on the fatigue behaviour of noise barriers for high speed railways for train transits, threaded rods bonded with epoxy resin for column base plate anchorage had to be qualified. A fatigue test campaign was carried out at Fischer Laboratories in Denzlingen (Germany) on M20 and M30 (8.8 Grade) threaded rod samples embedded in concrete by means of FIS EM epoxy resin. The tests considered also threaded rods (M16 and M30, 8.8 Grade) not directly embedded in concrete, but in pre-cast corrugated pipes having a diameter constant and equal to 40 mm.
The results were found to be very satisfactory as far as the resin performance was concerned. In fact, under tensile loads carried out under a nominal load ratio R 0, all fatigue failures took place in the threaded rods, under the nut, notwithstanding the embedment length was that suggested by technical manuals for static loading. Some typical fracture surfaces relating to medium and high cycle fatigue regime are documented.
A statistical re-analysis has been carried out considering also other data, either obtained at Fischer laboratories from analogous threaded applications or taken from the literature. A new scatterband is provided for threaded rods with diameter equal to or less than 20 mm
- …
