Description
Steel structures, such as bridges, must be continuously maintained. Due to increasing traffic loads, design and execution shortcomings, many steel bridges are subject to various types of damage, such as cracks. To address these problems, it is necessary to perform maintenance, typically by removing these cracks by re-welding. During this repair process, the affected bridge needs to be closed to traffic in order to prevent crack movement during the welding. Due to this closure, traffic is diverted to alternate routes, increasing the traffic loads on those routes, which, unfortunately leads to additional damage and subsequent welding work and costs for these alternate structures. Therefore, the primary goal is to establish a method that allows welding work on steel structures while traffic is flowing. In order to achieve this, measurements were first conducted at a representative steel bridge to derive gap opening parameters of amplitude and frequency for welding tests under cyclic loading. Subsequently the weld quality and the fatigue performance were quantified. The weld quality and the fatigue strength were comparable to standard requirements, so that welding under service conditions is possible under certain aspects.
In this paper, it will be presented which crack monitoring techniques can be used to quantify the gap opening. A repair strategy for butt joints is presented, along with data on the fatigue strengths achieved. It is also shown how this repair process can be documented in a digital twin framework.
