The Research On Theory And Experiment About Steel-Deck SMA Pavement Technology

The steel-structure girder has been widely adopted as the super structure of extra-long span bridges, because of its hypertension, gigantic-stiffness, light-weight and convenience of construction as well. In China, especially since the 1990s, steel-structures have been introduced into a lot of grand bridges which spanned over roaring rivers and surging seas. Steel decks, in other words, orthodox isomerism structures, are welded with various transverse and longitudinal reinforcing ribs. This results in the complexity of forces and deformatiort of the pavement layer above the deck. In addition, due to the good thermal conductivity of steel materials, the pavement layer upon the deck should have good thermal stabilities and low temperature deformation abilities.In terms of paving materials and erecting methods, the steel deck pavement systems adopted in the world can be generalized into four types:The first one is the Gussasphalt. Then is the Mastic Asphalt. Another one is the Stone Mastic Asphalt. And the last one is the Epoxy Asphalt.SMA has been widely applied in western countries such as European countries, Japan and America for its strong anti-track capability and well durability. It is still under experimental stage yet in China.In this paper, a high performance SMA system applied to steel bridge deck is put forth in allusion to the pavement project of the Wuhan Junshan Yangtze River Highway Bridge. It comprises steel slab, Zn coating layer, closing layer, adhesive, pre-mixed asphalt stone and dual layer SMA from bottom to top. It is based on the FEA results of the forces and deformation of the pavement layer by means of the ALGOR FEAS, according to this bridge's traffic and the ambient temperature varying range of the pavement layer. The ingredients of this type of SMA system, such as altering asphalt, aggregations, mineral powder and fiber, have been studied deeply. Various components have been compared in detail as well. Therefore, the appropriate component of this type of SMA was decided. Furthermore, several experiments aboutthe fatigue performance of the pavement and the SMA mixture's performance had been carried out. All these experimental results verify and vouch for the feasibility of the SMA system concerned above.