Launching of the Vaux Viaduct

Environmental concerns played an important role in the planning of the last stretch of the A1 highway between Lausanne and Bern. Bridges and tunnels represent more than 72% of the length of this stretch of highway. One of the bridges is the Vaux Viaduct. This steel-concrete composite bridge, with launched main spans of 130 m, is another step of progress in composite bridge design and construction in Switzerland over the last three decades. The launching of the Vaux Viaduct required careful planning based on detailed calculations considering the patch-loading resistance and the complicated geometry of the bridges. These calculations allowed the most important parameters to be identified and subsequently monitored with view to keeping them within allowable limits. The monitoring of support reactions and adjustment of support levels during launching enabled the successful completion of the complex erection process.