Composite Dowels in Bridges - Efficient Solution

Abstract

The bridges are vital structures for the transport infrastructure; it is a fact that, in the last decades, composite bridges became a well-liked solution in many European countries as a cost-effective and aesthetic alternative to concrete bridges. Their competitiveness depends on several circumstances such as site conditions, local costs of material and staff and the contractors experience. Beside the classical solution, the new ones with efficient design and construction improve and consolidate the market position of the steel construction and steel producing industry. These bridge solutions combine many important aspects: reduced costs, fast and simple erection, durability and robustness, low maintenance costs and an appealing aesthetical aspect. Another feature is the robustness of composite bridges. The robustness of a structure has to be defined as being the capacity of the system to keep its structural integrity for any kind of action that may occur during its service life. The present tendency in composite bridges consists in simplifying the structure as much as possible. Continuous shear connection using a cut steel strip is a solution for composite beams. With the introduction of the composite dowel the possibility is given to develop new construction methods for bridges. The paper will include interesting aspects regarding the dimensioning of the structure and technological features and also aspects related to the efficiency, robustness and fatigue behavior of the joints with composite dowels in bridges. The behavior of the dowels has a theoretical background based on laboratory investigations. The Romanian railway and highway infrastructure is presently involved in a large operation of renewal and modernization. The solution was recently introduced in Romania for three highway bridges of medium spans.