Applied Mechanics and Materials Vols. 256-259

Abstract: Water erosion was the main pavement disease, and the erosion resistibility of synchronous pavement surface dressing composite structure was evaluated. Specimens’ immersion corrosion tests in still water, vibration water and under the scouring condition were carried out for the research on the corrosion resistance. It is observed that corrosion resistance and scour resistance performances are significantly reduce with the water temperature and immersion time. The diseases of composite synchronous surface dressing are increased beyond 48 hours immersion time. Finally, it is observed that the performance of corrosion resistance decrease significantly when the running speed higher than 60km/h.

Abstract: Plenty of cultivated land has been used for highway construction. Thus Land-saving mode in road construction has drawn more and more attentions. However, inappropriate land-saving mode may result in some kinds of risks during highway's service life. Based on road risk, this paper discusses land-saving mode of Congo (Brazzaville) Highway One (Phase Ⅱ), trying to reach the balance between the two after accomplishing literature review and analyzing the prediction of traffic flow. The result shows that, the project should choose the mode such as proper construction scale and high bridge & tunnel ratio, rather than small turning radius and low roadbed.

Abstract: The use of modified asphalt binders has become much more common over the past two decades. Many types of modifier have been used in paving asphalts to enhance the performance of asphalt pavements in a wide range of climates and loading conditions. Among various asphalts binder modifiers, the recycled crumb rubber has been used very successfully for many years. Generally in production of CRM binder, mixing and compaction temperature is determined by measuring of binder viscosity. The ordinary method used for viscosity measurement of unmodified binder leads to a very high Mixing and Compaction Temperature (MCT) for CRM binder. The aims of this paper are to identify, develop and give some recommendations on a reliable laboratory approach for blending of CRM with binder, as well as introducing appropriate laboratory test methods for optimisation of MCT of crumb rubber modified binder asphalt.

Abstract: Through the crush value test and combustion method test to analyze the relationship between needle flake content and crush value，and analyze the affection to the status of broken at compaction procession .Through the use of static pressure, gyratory compaction and Marshall compaction this three different molding methods of rubber asphalt mixture specimen shape.At the same time, analyze the variation of volume parameters and combination with the methods of specimen trimming to analyze its porosity distribution. At the same time, forming the sample volume parameters and combination of slices to analyze the porosity distribution of three different ways. The same time, through combustion method to analyze the impact of molding methods on rubber asphalt mixture's compaction characteristics.

Abstract: To discuss basalt fiber adding quantity to the influence of Marshall test results of asphalt mixture. Through the Marshall test, the changing regulation of marshal indexes of various grading asphalt mixture with different basalt fiber adding quantity were studied respectively, and comparative analysis of Marshall index with xylogen fiber polyester and fiber asphalt mixture were done. The results show that the improvement effects for Marshall index are remarkable by addition of fiber, and compared with polyester fiber and xylogen fiber, the improvement effects of basalt fiber is better.

Abstract: he experimentation was to study the effect to cement concrete surface flexural strength by simulating the different natures and thickness of cement mortar, The slump was defined as 20mm and 70mm, on behalf of the low plasticity of concrete and plastic concrete, the three conditions of the surface mortar thickness 25mm, 15mm and 5mm was to simulate the different thickness of mortar extracted during concrete construction,which adopted three different mortar ratio and mortar consistency, the concrete specimens with the 150*150*550mm steel mould were made from concrete and the surface layer of mortar,the specimen surface as a curved flat was to determine the surface flexural tensile strength.The results show that: the surface flexural strength of concrete is affected by the components,natures and thickness of cement mortar, the higher the surface mortar strength is, the higher concrete surface bending strength is.

Abstract: Engineering must maintain and repair the whole track bed daily and timely. Considering the different geographical conditions of the construction, soil conditions and the different construction methods and other factors, engineering methods adopted are not the same reinforcement. Mainly three categories: the repair of minor cracks in the surface of the coating law, pressure grouting which has a good condition of strength and durability, grooving repair methods. This paper focuses on various types of reinforcement construction methods for comparison.

Abstract: In order to find out the loading mechanism of Fly-Ash-Flushed-by-Seawater base asphalt pavement under heavy load and verify reasonable road pavement structure, this paper analysed the road model under different axel load with ABAQUS. The influence of structural stress and the road asphalt pavement deflection in different road structural parameters were shown in the paper. The result indicates that the structural stress and the deflection under heavy load are greater than they are under the standard load. When the vehicle is over load by 100％, the tensile stress of subbase is close to the allowable tensile stress. The structure of Fly-Ash-Flushed-by-Seawater base asphalt pavement can be designed to adapt to the over load traffic of Yingkou by adjusted the structural parameter in a certain range.

Abstract: It was identified in previous research that errors in theoretical damage much associated with the influence function calculation. Thus, this paper present the efficient prediction of primary response due to dynamic vehicle loading using influence function and peak influence function approach. In order to provide the realistic loading condition, dynamic road response model with idealised loads representative by mathematical quarter-truck model with two degree of freedom was excited by a random road surface profile which equally spaced points along the simulated road with various different speeds. Consequently, the simplified computational approach (peak influence function method) was identified only a few points gave a small different compare with the influence function method for along the longitudinal distance. In order to identify the impact of both methods, further implementation was done to calculate fatigue damage (horizontal tensile strain at the bottom of a bound layer) or rutting damage (vertical compressive strain at the top of the subgrade layer) predicted by constant load moving at varies speed. It was found that the differences in response are particularly small and increased steadily as the increasing of the vehicle speed. It was conclude that the simplify calculation was able to predict stresses and strains sufficiently accurately and identified relatively small errors into the pavement damage prediction. Hence the simplification in particular much reduced the computation time sufficiently and minimized the computer resources significantly.

Abstract: In domestic asphalt pavement micro-surfacing technology is a new kind of pavement maintenance technology. Starting with the micro-surfacing technology application effect, we analyzed the micro-surfacing technology characteristics and application conditions. We also analyzed and discussed the application prospect, strive to provide a technical reference for promotion and application of micro surfacing technology.