Damage accumulation and resistance decrease inevitably happen to bridge structures due to the effects of earthquakes, impact loads, wind load and corrosion during their service time. Once the damages of the key components accumulate to a certain level, they would spread promptly, causing the sudden destruction of the whole structure if not found and dealt with in time. So the structural damages would not only shorten the operation life of structure but also threaten the human lives and financial safety. Therefore, the technology of damage diagnosis of bridge structure holds supreme significance. This paper summarized the current research situation of the existing bridge diagnosis methods and analyzed the characteristics of each method through the reading and studying of the related material both domestically and internationally. Among those methods, only the diagnosis method based on load tests is the most direct and effective one for current bridge diagnosis, the diagnosis results of which shows higher reliability. And the structural dynamic characteristic method based on dynamic load tests could beautifully avoid the disadvantages of the static load tests, becoming the main development direction of rapid diagnosis of bridge. Furthermore, lastly it elaborated the analysis of the key problems of breaking through the development bottleneck of current rapid diagnosis methods of bridge, creating a solid foundation for the future research.

Based on ABAQUS software, a 3-D finite element model which content the nonlinear contact problems and contact-earth subgrade-monilithic was given to analysis the mechanical behavior of the monolithic roadbed. Mechanics behavior and deflection of the monolithic roadbed, deflection and compressive stress of earth subgrade evaluated in detail with respect to varied structure layer combination and materials parameters. The results indicate that the increase roadbed thickness can significantly reduce the monolithic roadbeds tensile stress, which can reach 1.042MPa. With the increase of the friction coefficient, level of tensile stress σdy, monolithic deflection Dd , the compressive stress σsz and deflection on earth subgrade were slightly reduced.

According to the test results of before and after the aging of asphalt performance,we analyse the dosage changes of the HALS anti ultraviolet ageing agent to improve SBS modified asphalt ultraviolet light resistance aging performance role. The test results show that GW-944 can better improve the ultraviolet resistance of asphalt aging performance, i.e., original sample asphalt have no other negative influence in a certain extent, and at the same time,also improve asphalt fatigue performance, low temperature performance and high temperature performance after the light aging, but the performance improvement needs to be in the right dosage range;Therefore,to the SBS modified asphalt we can use such ultraviolet aging agent for performance improvement,the research achievement for the airport asphalt pavement UV aging provide a technical basis for effective prevention and treatment.

The Aircraft Classification Number-Pavement Classification Number method is the main approach for evaluating the structure of the airport pavement. However, the weakness of exiting methods lies in the difficulty of obtaining the exact PCN of the airport from the Airports Authority. This paper investigated the attenuation behaviors of the pavement structure under the envrionment of aircraft operation, and then the improved evaluation method for airport pavement was presented. The improved method could provide the technical support for accurately judging the bearing capacity of the exiting pavement structure and supply the decision-making reference to the Airports Authority.

Based on the differences between the subgrade of tramcar with monolithic track-bed and the existing subgrade of railway, anew three-dimensional nonlinear finite element model is established in this paper. And then,the numerical analyses are conducted by considering weight load of track structure. The characteristics of mechanical response in the subgrade of tramcar with monolithic track-bed are found by finite analysis, which offers a reference for the future engineering, in terms of the design concept, design basis and theoretical support as well as the basis for decision making.