Applied Mechanics and Materials Vols. 97-98

Abstract: In order to study the rutting problem of asphalt pavement, this paper sets up a three-dimensional model of asphalt pavement with finite element. By analyzing the mechanical response of high-modulus asphalt concrete at different layers, this paper finds out the layer set of high-modulus asphalt concrete. At the same time, it further analyzes the influence of the modulus’ size and thickness of the high-modulus asphalt concrete on the load-carrying capability of road structure. The results show that high-modulus asphalt concrete can significantly restrain rutting problem and the recommend ideal modulus is between 2000MPa and 2500MPa; the ideal thickness ranges from 5cm to 7cm.

Abstract: For adopting to the difficult terrain and restricted conditions, a probability of using the concept of inverted function into interchange linear to optimized design is built, which use the inverted function y=a/x as the interchange right-turn ramp linear. This function can be corresponded to the vehicle trajectory, decrease the area and cut the cost of interchange compared with the ordinary way“spiral-circle-spiral”.By the analysis of how to use this function linear to be ramp, this paper get the way to set the ends of the ramp by circular curve or spiral curve. And this paper also take application example to illustrate the specific solution of how to use the inverted function to set the interchange right-turn ramp.

Abstract: With the aggravation of high grade highway asphalt pavement destructions, it becomes particularly important to maintain pavement performance and enhance road economic efficiency. The asphalt pavement preventive maintenance technology is an effective technique to extend pavement services and maintain pavement performance. In this paper, we combine the decay model of pavement performance with assets value evaluation idea and establish an analytical method about preventive maintenance technology based on assets evaluation. An example of hot asphalt overlay is also presented, it is found that preventive maintenance techniques can reduce the attenuation of road infrastructure assets value and maintain pavement performance efficiently.

Abstract: Based on the indoor shear test stimulation of the interface bonding force status of concrete bridge deck waterproof layers, conduct systematically analysis of various factors and regulations in layer shear resistance, in terms of asphalt spraying amount, gravel spreading type, bridge panel interface treatment conditions and environmental temperature, etc, to propose various technical measures for improving the shear resistance performance between rubber-asphalt waterproofing adhesive layers thus provide experimental basis and data support for the practical applications and construction quality. Research concludes that: in order to give full play to the shear resistance performance between rubber-asphalt waterproofing adhesive layers, the shear resistance and bond performance in high temperature state must be strictly controlled, the spray volume and spray temperature should be controlled at 1.8~2.2 kg/m2 and 190~200 °C.Meanwhile, the spreading gravels should be clean with preheating treatment, the diameter ranging from 2.36 mm to 4.75 mm; the spraying volume should be about 10kg/m2. In addition, the bridge panel surface coarseness should be controlled within a reasonable context, when the anti-sliding value is between 45 to 55, the maximum value of interlayer shear resistance strength appears.

Abstract: The subject Introduced the analysis method of the black-spot, established the black-spot discriminant model, And gave its algorithm. According to the characteristics of China's traffic flow, we develope black-spot database, so that the work of the black-spot identification can be quickly carried out。The Road black-spot traffic accidents describes the road sections which have significantly higher accident rate than the average level . Road black-spots identification, analysis and processing are widely considered to be the most efficient way to prevent traffic accidents. The identification of Road accident black-spots is the concern of road design, road safety review, operation management, and security studies , The research studies of road black-spot identification,and determines risk road sections, so that countermeasures can be put forward, and we can achieve the goals of design improvement, strengthen management, improvement of road safety operation environment, decrease of the number of traffic accidents and improvement of the whole road traffic safety performance.

Abstract: In order to solve problems such as environmental contamination, large resource consuming, and the inflammability of present asphalt mixture, a warm-mix agent was chosen and fire retardant was added to asphalt to modify its characteristics. The anti-flaming and warm-mix asphalt has been produced in the orthogonal experiment, and its road property and anti-flaming property lived up to expectation. The experiment shows that under the condition of a lower temperature (15-20°C lower than the the mix temperature), the rutting resistance of the anti-flaming and warm-mix SBS modified asphalt , but its low temperature property and water sensitivity decreased. This asphalt has excellent anti-flaming characteristic, and thus it can decrease the property loss in case of fire.

Abstract: In this paper, the influence of compound mineral admixture on cement mortar’s performance is studied. The optimum compound proportion of compound mineral admixture and the suitable substitution amount can be obtained. The analysis work is carried out on the additive effect of compound mineral admixture. It is shown that the mineral admixture has many advantages, such as improving the performance of cement mortar, making full use of waste, reducing the cost and environmental protection.

Abstract: A calculation method of wheel-rail multi-point contact based on the elastic contact model is introduced. Moreover, the simulation calculation of vehicles passing through branch lines of No.18 turnouts is carried out. The result showed that the acute change of wheel-rail normal force caused by the transfers of wheel-rail contact point between two rails can be avoid by wheel-rail multi-point contact method, and the transfers of wheel-rail normal force between two rails is smoother. The validity of wheel-rail multi-point contact method is verified.

Abstract: Digital Channel has been an imperative need for the channel, yet few literatures about it are presented. This paper proposes a method to block the channel according to the contours and the banks, delete the data of the seabed on the basis of scope of bank and seabed, by using radial basis function to interpolate the data of seabed and adds them to the corresponding blocks. Finally dynamic Delaunay triangulations constrained by seabed edges within updating blocks are obtained.

Abstract: It applies flight dynamics and vibration principle to create vibration model of aircraft landing gear considering aircraft tire damping, and get the equation of analytical solution based on the impact on airfield pavement roughness. It studies the relationship between dynamic load coefficient and time and speed and roughness. For a special aircraft, it gives the allowable level for pavement roughness based on the influence of pavement and passengers comfort.