The behaviour of clothoid-shaped composite dowels: Experimental and numerical investigations

Abstract

Investigations leading to an evaluation of the ultimate strength of a clothoid-shaped continuous shear connection are presented. This paper follows a study by the authors, in which the behaviour of puzzle-shaped composite dowels was evaluated. Owing to its good fatigue, elastic and ultimate strength, the modified clothoidal dowel shape (MCL) is now most commonly used for the continuous connector. A method of evaluating the strength, stiffness and ductility of the dowel is described. The method is based on experimental studies and FE analyses of the dowel's steel part and concrete part. A mechanical model of the dowel's steel part, based on numerical analyses, is presented. Push-out tests were carried out on specimens differing in the thickness of connectors. The test results and the results yielded by other methods are compared and discussed. The research done by the authors provided the basis for the evaluation of the ultimate limit state (ULS) of composite dowels used in the construction of many road and railway bridges, and for the development of the current design rules.