No abstract

<p>The problem of bridge fires is growing. Because of a bad experience in Poland, it was decided to improve fire resistance of long span bridge structures, and of cable-stayed bridges in particular. Statistics shows that fire is a real threat to this kind of structure. They also confirm that the worst results of fire are for those with an orthotropic deck rather than with a concrete one. The basic problems to solve are how to predict fire resistance of a particular bridge and how to ensure safety and structural integrity of the bridge structure. Taking into account the fact that bridge standards do not include information relating to fire protection, and fire standards do not determine rules for design, construction and maintenance of such structures, there are no regulations for this problem. Fire scenarios are devoted to buildings, but the thermo-structural behavior of bridges is different.</p>

No abstract

<p>The problem of bridge fire is growing. Because of bad experience in Warsaw, Poland local government decided to prove fire resistance of all bridge structures across Vistula river which pass through the city. One of such bridges is six spans continuous truss – 400 m long - with double deck: upper is concrete highway deck and lower is timber tramway deck. Possibility of occurrence of fire on tramway bridge with timber deck inclined the owner of the bridge to exchange whole deck and sleepers in particular. Because the load capacity of the bridge was drew out it was not possible to apply steel or concrete sleepers. Therefore the owner decided to fit up synthetic wood sleepers. To be sure that this kind of sleepers mounted on the bridge is safe special research program was introduced. The results of investigation proofed good structural material properties and good fire resistance of sleepers. Proposal of new structural solution of the bridge is also given.</p>