This volume contains the results obtained by a symposium which took place in Paris, France, on May 04-05, 1999, hosted by the International Union of Railways, UIC. This symposium was organised within the framework of the Brite/Euram project TRANSAERO. The TRANSAERO project bundles the expertise of three railway companies and eight universities and research institutions in Europe to improve the physical understanding of the time-dependent effects of sidewind forces, train passing and pressure waves in tunnels. The goal was to find efficient and economically satisfying solutions to these...