Experimental determination of the fatigue behavior of dowel strips in ortho‐composite slabs for road bridges

Abstract

In contrast to reinforced concrete and conventional composite bridges, the orthotropic steel deck slab offers a high load‐bearing capacity combined with a low dead weight. It is therefore ideally suited for slender and long‐span structures. However, the notch sharpness in the details and drastically increased traffic loads led to extensive fatigue damage and, as a consequence, often to premature repair or replacement work. With the ortho‐composite slab a lightweight and robust construction is currently being developed as an alternative. It combines the significant advantages of a low dead weight, long service life and economical production. The construction consists of a modified orthotropic stiffened steel plate and a thin, single‐layer reinforced in‐situ concrete. Composite dowel strips (CDS) with a clothoid shape are provided as shear connectors. In this paper, the experimental test program will be introduced. It comprises static push‐out tests on CDS in longitudinal and transverse directions as well as static and cyclic beam and segment tests. The focus lies on the test set‐ups, sample preparations, measurement concepts and the results of the so‐called beam tests. The investigations presented here were carried out as part of the AiF‐FOSTA research project P1265 [1].

Numerical investigations of the load‐bearing and fatigue behavior of orthotropic composite slabs for road bridges

“…The investigations create important foundations for the establishment of the innovative construction method as an economical and durable alternative. The papers [2] and [3] give an overview of the construction and the load bearing behavior of the OC-Slab, the paper [4] details about the experimental test program. This paper describes the numerical investigations carried out.…”

“…This corresponded to the smallest wheel contact area according to DIN EN 1991-2 [6]. A detailed description of the test set-up and the achievements can be found in [4].…”

“…The specimen had a length of 0.6 m in the direction of the roadway slab and a width that included two longitudinal stiffeners, the specimen dimensions were 0.6 x 2.1 m (Figure 2). Seesaw bearings were developed to simulate the support effect of the longitudinal stiffeners (see [4]). Their design was based on comparative calculations on a bridge segment.…”

“…The distance between the upper spherical bearings corresponds to the distance of the webs of the trapezoidal hollow stiffeners. The lower bearings were arranged so that the load distribution corresponds to that of a bridge segment with a local wheel load at midspan between two cross girders, [4]. The load was applied centrally through a 320 x 220 mm steel plate.…”

Orthotropic composite slabs for road bridges

“…1). More detailed information can be found in the research report and other publications (cf [1],[2].…”