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Abstract: The evaluation of existing structures, in particular bridges, is becoming increasingly important. In particular for railway bridges, service loads and stress cycles accumulated under traffic loads, and the consequent ageing of existing structures, lead to the need for an assessment of their remaining fatigue life, in order to decide on retrofit or structure replacement. In this context, a 12.4 m span railway bridge near Sacile, Italy, with a common structural scheme for railway bridges, about ninety years old, was taken out of service, transported to a structural laboratory and subjected to both material characterization, monotonic and high-cycle fatigue shear tests. Materials exhibited a yield strength and a tensile strength of about 322 and 421 MPa, respectively, and the hot-spot critical details resulted in the riveted connections of the shear diaphragms that carried the rails. Other material properties that affected the fatigue endurance in a favorable way, and are not taken explicitly into account in structural Codes, were determined. As a result, the equating of riveted shear splices with splices jointed with non-preloaded bolts has been shown, and Eurocode 3-1-9 [EN 1993-1-9. Eurocode 3: Design of steel structures — part 1-9: Fatigue, Brussels: CEN; 2005] design rules have resulted on the safe side, even though no specific category of riveted details has been found to be available. [Copyright &y& Elsevier]

The Anca Dual Fit hip stem (Cremascoli Wright, Milan, Italy) is a partially cemented stem developed to overcome the drawbacks of both cemented and uncemented fixations. Its design was based on the hypothesis that partial cementing would ensure the primary stability necessary to allow bone ingrowth on the cement-free stem surfaces. At the same time, the limitation of the cement to the proximal regions would prevent stress-shielding by increasing proximal load transfer. After finite element (FE) simulations and in vitro primary stability assessment, an analysis of the long-term stability of the Anca Dual Fit stem was necessary to conclude the preclinical testing. Three stems were implanted in composite femurs and subjected to testing for 1 x 10(6) cycles, each cycle reproducing the activity of stair climbing. The simulation was designed so as to replicate the physiological loading in a simplified, yet relevant way for this test. Various measurements were collected before, during and after the test in order to give exhaustive information on the response of the implant to long-term, cyclic loading. The present study confirmed the positive results of previous investigations, and proved that the Anca Dual Fit stem has excellent long-term stability; therefore successful clinical outcomes are predicted. [ABSTRACT FROM AUTHOR]