Search

The simplified method of the equivalent compression flange represents an illustrative and easy‐to‐use engineering model for lateral torsional buckling. The basic concept of the verification procedure has existed since its introduction in the 1950s. It is still frequently used today for preliminary design and application cases where the solution of the 'correct lateral torsional buckling problem' is complex and time‐consuming. To adapt the method to the current state of the art, it was further developed in the framework of the Eurocode 3 evolution. This 'new' method is part of the second generation of Eurocode 3, Part 1‐1 and is valid for classes 1 to 3 cross sections in major axis bending. The method must be adapted for use in other contexts and for specific applications. Applying the equivalent compression flange verification method to the structural fire design of building structures must consider the temperature‐dependent material properties of steel and their impact on the stability behaviour. Moreover, typical applications for bridge structures, runway beams, and H‐piles in combined walls require additional consideration of class 4 cross sections and various combined loadings, e. g., N–M interaction behaviour. This article presents theoretical studies on extending the simplified method of the equivalent compression flange to meet these demands. Finally, the application of the verification method is demonstrated in working examples. [ABSTRACT FROM AUTHOR]

Timber–concrete composite (TCC) structural systems are characterized by the combination of timber and concrete, which are connected to transmit shear forces between the two elements. In addition, to achieve an efficient connection, the slip between the two materials should be limited. Therefore, the load-carrying capacity, the stiffness, and the failure mode of TCC connections are important for the behavior of the composite element. This work aims to investigate the influence of test conditions on TCC connections using shear tests to determine the mechanical properties of connections. Therefore, it is essential to understand the influence of the configuration of the specimens (symmetric as push-out tests or asymmetric as inclined tests), the type of interface between the timber and concrete, and the test procedure (static or cyclic load protocol) on the resulting load-carrying capacity, stiffness, and failure modes. This paper reviews experimental tests conducted on TCC shear connection specimens, using various configurations to assess the influence of the test specimen configuration, material interface, and testing protocol on the determination of the mechanical properties. [ABSTRACT FROM AUTHOR]

Fatigue strength of concrete decks for large composite bridges In the support area of large composite bridges, tensile stresses occur in the concrete deck slab due to the negative bending moment of the main girders, leading to cracks in the concrete deck. Transverse steel cantilever beams are arranged under the deck at the transverse frame spacing in order to support e. g. prefabricated concrete elements, so that the deck slab predominantly spans in the longitudinal direction. Cyclic transverse forces due to local wheel loads caused by high variable traffic loads must then be transferred to the cross girders via the cracked concrete slab, as a result of the tensile loading. Up to now, no tests have been carried out to determine the fatigue strength of the cracked concrete deck slab. Based on tests from the literature (whereby so far only well documented tests without longitudinal tensile loading have been available) and own experiments (with longitudinal tensile loading), a database has been developed which formed the basis for the derivation of S‐N‐lines and which allowed the evaluation of the influence of specific parameters on the fatigue strength. Since the fatigue strength of reinforced concrete elements without shear reinforcement is dependent on the static load‐bearing capacity, the influence of the scatter of the static shear capacity on the fatigue strength is discussed in particular. Based on the results and the current state of standardization, a design concept for the fatigue strength of the concrete deck slab is presented. [ABSTRACT FROM AUTHOR]