Applied Mechanics and Materials Vols. 744-746

Abstract: This paper established a three-dimensional model of asphalt pavement by finite element analysis method, studied the effects of vehicle braking on the asphalt pavement, and analyzed the mechanical law of asphalt pavement through comparing the stress of pavement asphalt when the vehicle is in uniform motion or braking condition. The results show that the vertical stress, vertical displacement and horizontal shear stress of the asphalt pavement increase significantly while the vehicle is under the braking condition. In every asphalt pavement structure layer, the maximum horizontal shear stress under vehicle braking condition are all about four times to that of under vehicle uniform motion, so it’s necessary to significantly improve the shear strength of the asphalt pavement in these sections which often bear automobile braking force.

Abstract: The pavement performance study of bituminous mixture at surface course is very important. This paper focused on comparing the pavement performance of AC-l6C, AC-l6F, Super-12.5 and SMA-16 bituminous mixtures. First the gradations and material we used were illustrated. Then the dynamic stability, water stability and texture depth of these bituminous mixtures was tested. After comparing the test data, we found that the SMA-16 bituminous mixture has the best comprehensive pavement performance and it is most suitable for the surface layer bituminous mixture of freeways in Chinese Hubei Province. Super-12.5 and AC-l6C is applicable too, but AC-l6F is improper in this region.

Abstract: Survey data show the problem of weak foundation existing in an accommodation highway. There are many methods to treat the soft foundation, and different methods have different expenses, effects and construction periods. Through the deep comparison of four foundation treatment programs, dynamic compaction method is taken for the design, and the detection result shows that the treatment effect reaches the engineering requirements.

Abstract: In this paper, the problems existing in highway landscape design is studied on. The quantitative analysis index system of highway landscape design is set up, which is made up of diversity indices, spatial indices, sensitivity indices. The method of determining these indices is analyzed. In sensitivity indices, landscape sensitivity index and visual acuity index are set up based on the dynamic and static characters of highway landscape.

Abstract: In order to analyze the dynamic response of asphalt pavement under vehicle load, the random characteristic of pavement roughness was considered and the vehicle was simplified into 1/2 model with four freedom degrees when establishing the dynamic load model. Then the sequence of the random dynamic load coefficient was obtained by developing a MATLAB program based on the incremental Newmark-β method. Based on the plane strain assumption, a two-dimensional layered finite element model of asphalt pavement was established by ABAQUS software. Then the dynamic load coefficient was used to modify tire pressure that would be applied on the ABAQUS model. Then dynamic response rule of the model and how it was effected by vehicle speed were studied under random load. The results show that under the condition of random load, dynamic response of the pavement structure exhibiting a fluctuation trend as vehicle speed increases and the dynamic response characteristics of each point is different.

Abstract: Characterized with efficient, accurate and non-contact measurement, and the fast and three-dimensional visualization features, using 3D terrestrial laser scanning technology in track static detection has attracted widespread attention. Based on the structural characteristics of the railway line, use Geomagic software and Cyclone software in the pre-processing stage, remove the noise and redundancy, package the data after registration, get the initial line model finally. In the data extraction stage, combined with professional needs, respectively research the data extraction of track pitch and direction, and the bed section, from line, plane, and body. Which have provided a good research idea for using 3D terrestrial laser scanning technology in track static detection, acceptance, and some other aspects.

Abstract: Combined with the test data from track inspection car in some section of Lan-Xin railway, the paper researches the application of TQI in guiding line maintenance and repair. Analyze the changing trends of rail operation quality according to the statistical data, put forward calculation method of the average line deterioration index to the particular section, predict the track quality life and the maintenance cycle, and reasonably arrange the maintenance and repair time during line overhaul. By accurately using the value of TQI to guiding line maintenance and repair, rationally plan the best time of maintenance and repair, ensure the line in equilibrium and steady state.

Abstract: This paper studied the performance of SBS modified Karamay asphalt and asphalt mixtures for the purpose of widely applies it to Xinjiang highway. The effects of the different compositions of equal density modifier on modified asphalt and the compatibility of the matrix asphalt with its modifier were investigated by adjusting the content of reclaimed rubber and SBS polymer. Experiment results indicate that modified asphalt has the best performance when the modifier particles consist of 48.6% SBS polymer, 43.2% reclaimed rubber and 8.2% adjuvant. It is shown that the applying of modifier particles can improve the performance of Karamay modified asphalt and HMA (Hot Mix Asphalt) dramatically.

Abstract: Highway landscape road will enhance coordination and harmony with the environment; effectively reduce driver fatigue, so that it remains adequate attention to driving a vehicle, thereby reducing traffic accidents, guarantee safe and smooth road. Highway landscape sequence, spatial form of roadside structures and roads with a minimum length of the curve between studied. Highway Greening emphasize ecological function should be considered, landscaping features, combined with a wide range of perfect coordination function surrounding environment, transport and other ancillary facilities function.

Abstract: In order to deeply reveal the high temperature stability of asphalt mixture, rutting test was implemented to evaluate the high temperature stability of asphalt mixture, and the evaluation index is dynamic stability. The effect of asphalt type, degree of compaction, gradation type and nominal maximum aggregate size on rutting test results was studied respectively. The results showed that: modified asphalt can improve the high temperature stability of asphalt mixture effectively; the anti-rutting performance of asphalt mixture reduces gradually with decrease of the degree of compaction; the anti-rutting performance of SAC-16 is greater than that of AC-16; and the anti-rutting performance of asphalt mixture is improved with increase of the nominal size of aggregate.