Research On Crack Deterioration Of Long-span Bridges Deck Pavement

Deck paving is a technical problem in the construction of long-span bridges. The conditions and requirements of the application of surfacing are far more stringent than these of ordinary road pavements. Now more long-span steel bridges are constructed in our country, and more internal researchers pay attentions to the deck pavement cracking deteriorations problems. Making some mechanical researches on the paving structures and crack propagation would benefit paving design and provide theoretic indexes for the deck paving deteriorations researches.By investigating the crack deterioration on asphalt pavement of long-span bridges, the crack types and deterioration configuration were analyzed in this dissertation. The result shows that longitudinal cracks are the most deteriorations and the cracks extend furtherly without repairing in time.Considering the crack tip stress singularities, finite element analysis models using substance elements with 20 joints and singular element were established , comparing the force of deck pavement with cracks to the deck pavement without cracks. The research result shows that longitudinal crack propagation accelerates transversal crack creating , pavement mechanical state become worse when cracking occurs, and then the cracks extend furtherly.Using finite element analysis method, the influences of crack situation and several parameters on pavement mechanical state, and the crack propagation direction were analyzed. The research result shows that crack length and depth influence the extend speed and extend form, so repairs should be applied before the worst deteriorations occur, the depth and modulus of asphalt pavement also are the main factors that influence the crack extend. The research result can suppose the crack direction and find suitable structure to prevent the crack extend.