The Bolintxu viaducts span the homonymous valley, which is a highly-valued ecological area, by means of very shallow composite weathering steel-concrete arches, built vertically and then lowered to protect the valley during construction. The design of these viaducts was a great technical challenge. The use of the composite typology in the arches and their lowering-method construction, required the development of parametric design tools that allow a fast iteration of the calculation models as well as their 3D export. This allowed the use of BIM technology from the beginning of the project, making it possible to achieve the high accuracy requirements necessary for the execution.
Miguel et al. (Wed,) studied this question.