| Deck overlay of long span bridge has become a tough technique problem in highway construction, along the development of highway in China. Although some success has been obtained in deck overlay of long span bridge in China, there are still some kinds of serious distress, such as high temperature rutting, fatigue crack, delamination. Especially big bridge is key hinge for traffic network. There is a high demand on life and reliability for deck overlay of long span bridge. It is very pressing to solve these problems to guide engineering practice, in that there are a number of long span bridges in construction or in plan, and many in need of repair in China. Bridge deck overlay is a complex and comprehensive subject including bridge structure, overlay structure, overlay material and binding course material. Deck overlay of long span concrete bridge is studied systematically, based on engineering of deck overlay of Yamen Bridge in Guangdong province in this dissertation. Yamen bridge is a long span prestressed concrete cable-stayed bridge with double tower and single cable plane. There is a higher demand on durability of Yamen bridge deck overlay, in that traffic has to be closed down in rehabilitating for the structure character of single cable plane. First, three levels methods mechanics analysis of deck overlay is made to understand the stress state and performance requirement of mechanics. I. On the assumption that bridge deck and overlay are continuous and deform in harmony, whole bridge deformation action upon deck overlay under the load of symmetrical vehicle, asymmetrical vehicle, and temperature are analyzed separately through three dimensions finite element method. II. Local deformation and strain state of bridge deck are analyzed through submodelling method. And the performance requirement of overlay under bridge deck local deformation is analyzed in contrast with common pavement structure. The methods of bridge deck local deformation analysis are summarized through comparing the results of submodelling and independent beam section methods. III. The stress state and distribution rule of inner bridge deck overlay are analyzed in details through computing the local bridge deck overlay model. Binding course's key function is analyzed through comparing the stress characters of deck overlay with continuous binding course and slip binding course. And the necessity to enforce anti fatigue performance of surface course asphalt mixture is analyzed. According the results of bridge deck overlay mechanics analysis, experimental study is made to binding course, key part of deck overlay of long span bridge. Experiment models of bevel shear, direct shear and direct pull are deigned. And four kinds of binding course material in common use are appraised through shear and direct pull tests. The constitution and influence factor of binding course are defined based on test results. Character and applicability of methods for appraising binding course performance are summarized at the same time. Influence of glass fiber grid on binding course is analyzed through comparing performance of the binding course with glass fiber grid or without glass fiber grid. And the influence of overlay mixture grade on binding course is analyzed through comparing performance of binding courses in different grade mixture deck overlays. At last, performance of modified asphalt is appraised according PG standard of SHRP. Fatigue performance of SMA (stone mastic asphalt) is compared with common AC asphalt using APA (asphalt pavement analyzer). And the fatigue performances of modified asphalt mixture and basic asphalt mixture are compared using APA. The excellent anti-fatigue performances of modified asphalt and SMA are summarized through these contrastive tests. The conclusions of bridge deck overlay mechanics analysis and tests in this dissertation have been applied in engineering practice. And these conclusions also can be theory reference for design and standardization of bridge deck overlay.
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