| Abstract: | ![]()
Particularities in the Design of Semi‐integral Prestressed Concrete Bridges An alternative bridge construction of increasing importance – illustrated by the example of the Fahrbach valley bridge near Aschaffenburg which is part of the autobahn A3. The integral construction method offers smaller concrete bridges, and increasingly concrete bridges of middle construction lengths, the optimum solution in many cases. A construction without joints or bearings allows low‐maintenance, robust and aesthetical structures. With the static analysis and constructive design of integral structures, the interactions between the superstructure, substructure and subsoil are solved by means of an optimization framework. In order to verify the feasibility of a semiintegral construction, the example of the currently under construction Fahrbach valley bridge is outlined here. Basic considerations are taken into account and their relevance for the design and execution planning is investigated. Recommendations, design aids and relevant boundary conditions for semi‐integral bridges are derived from this investigation. In particular the foundation has a significant influence on the design and the deformation behavior of the overall system. The loadings resulting from external actions (dead weight and traffic loads etc.) require a very stiff foundation. This contrasts the demands of temperature and the varying settlements of supports etc., which require an increasing flexibility of the foundation to manage the constraints. Hence, a realistic characterization of the soil properties of the subsoil is necessary for the static verification by consideration of lower and upper limit values. |
