Applied Mechanics and Materials Vols. 361-363

Abstract: Semi rigid asphalt pavement, flexible base asphalt and composite base asphalt pavement are the main structure forms of asphalt pavement. The mechanical distributions are different in those structures. Based on elastic layer system, this paper took the Shell designing software BISAR3.0 as calculation tool to get the tensile strain of three kinds of models, the distribution of main mechanical response were compared with each other using the ORIGIN8.0. Then a comprehensive analysis was made based on the mechanical response distributions of the three structures. The results show that: flexible tensile strain and vertical strain in the bottom of asphalt layers of semi rigid base structure is the smallest, as it shows better performance. It proves that the design specification adopting now is not suitable for semi rigid base pavement

Abstract: To study the fatigue life of asphalt pavement under traffic loads, a 3-D finite element analysis (FEA) Visio-elastic road model was established on the layered theory with ANSYS software. The fatigue damage was calculated with the maximum horizontal tensile strain of asphalt layer bottom based on the fatigue fracture mechanics, when single axis went across. Then the fatigue life was obtained after the fatigue damage occurred in some degree by the Miners linear cumulative damage rule. The results show that it taken 3.4 years when the damage area reached 10% of wheel path area, and 4.5years when reached 45%; while the calculated result was 5.5 years by axial-load conversion method. The analysis shows that the fatigue life of asphalt pavement calculated by fatigue fracture mechanics rule has more significance in practice.

Abstract: This paper explains the method and theory of cost net present value, and uses this method to analyses the economic benefits on several pavement inter layer (emulsified asphalt seal coat, rubber modified asphalt and stress absorbing layer of fiberglass polyester paving mat) during the 15-year period, results showed that rubber modified asphalt and stress absorbing layer of fiberglass polyester paving mat is superior to emulsified asphalt seal coat.

Abstract: Based on Weibull distribution, the function of coldrecycled base material fatigue life reliability is deduced. The basic parameter of reliability function is determined according to colrecycled material fatigue test results. The coldrecycled base material fatigue life reliability under the function of standard axial load is acquired with relevant calculation formula of asphalt pavement design specifications, and the fatigue life reliability of test road is estimated. The results show that the pure coldrecycled material is suitable for pavement structure of light traffic only, and the equation of fatigue life reliability is applicable and feasible.

Abstract: through analyzing the speed of the vehicles running on the highway, including the running speed and possible speed of the vehicle, the factors affecting the vehicle speed are studied, some advices of the vehicles safe running are given.

Abstract: This paper indoors for a sample of No90 asphalt has finished the asphalt aging, penetration, viscosity test at different temperature and time, comparing the indoor test results with the indexes of asphalt road actual use, the indoor test result and actual use aging relationship in all life-span service, to provide a reference method for the evaluation of asphalt anti-aging properties and selection of asphalt.

Abstract: This paper studies the technique used to set baselines for slipform paving of cement concrete pavement, proposes ways to improve the setting of baselines for different types of roads, brings forward precision requirements for setting baselines and determines the tensile force requirements for steel wires of different diameters through experiments.

Abstract: With the development of local economy, the increase of urban population and the poor infrastructure in old urban area cant meet the development of the modern city. Small and medium-sized city traffic problems have gradually become the negative factors which hinder and restrict the city social economy development. As viewed from Hohhot, this article mainly aims at the urban road asphalt pavement damage condition, analyses the main damage types and puts forward to the renovation and maintenance programs.

Abstract: This paper evalates the compaction property of the asphalt mixture through the densification curve of the Superpave Gyratory Compactor, introduces four factors such as CEI、TDI、k1、k2 to reflect the compaction property of the asphalt mixture under construction and traffic load, and analyses the compaction extent of the asphalt mixture with different CA.Based on the performance demand and the construction techniques,this paper gives reasonable range of the Bailey parameters CA.

Abstract: 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.