Applied Mechanics and Materials Vols. 587-589

Abstract: In this Paper, by Using the Finite Element Method, the Shrinkage Stress of Semi-Rigid Asphalt Pavement Structure was Analyzed. the Result Shows the Shrinkage Stress is the Key Factor Resulting in the Cracking of Semi-Rigid Base. the Dry Shrinkage Stress is Caused by the Subbase Frictional Resistance Preventing the Dry Shrinkage of Semi-Rigid Base, so it can be Assumed that the Dry Shrinkage Stress is Distributed Evenly in the Total Base. Meanwhile the Distribution Characteristics of Stress along Road Length, the Distribution Characteristics of Stress along Road Depth, the Effect of the Rate of Water Loss on Shrinkage Stress, the Effect of Temperature Difference on Temperature Shrinkage Stress, the Effect of Pavement Length on Shrinkage Stress and Dry Shrinkage Stress and Temperature Shrinkage Stress were Analyzed. the Resule would Provide the Basis for Structure Design and Material of Semi-Rigid Base.

Abstract: In recent years, Taiwan launched railway reconstruction projects to promote urban renewal and rural development. As the area of reconstruction projects is adjacent to the railway in operation, there are hidden risks to construction personnel and safety of the railway operations. The composite pier engineering method can improve construction safety and reduce risk. This paper presents a case study and discussion on risk management to provide the lesson learn for reference.

Abstract: In order to study the effectiveness of new type modified asphalt additive SBP on pavement performance of asphalt mixture, the experiments were carried out to evaluate the mixing and compaction temperature, high-temperature stability and water stability of SBP modified asphalt mixture. The high-temperature stability of the SBP modified asphalt mortar was studied by DSR. The heating temperature of mineral aggregate and the asphalt mixture mixing temperature and compacted temperature were determined by three different temperature asphalt mixture SCB test, which were got SGC (Superpave Gyratory Compactor). The wheel tracking test of asphalt mixture was carried to evaluate the high-temperature stability and freeze-thaw split test were studied the water stability. Through the wheel tracking test and water stability test in harsh condition, the high-temperature stability and water stability was evaluated again. It can be concluded that SBP can improve the pavement performances of asphalt mixtures.

Abstract: In order to make a better convergence of old and new roadbed,according to treatment technology about highway reconstruction project of new and old roadbed lap,we introduced the four good construction technology detailedly used in the construction process. Four kinds of processing technology can significantly reduce differential settlement caused by road diseases,and strengthen the widening subgrade integrity.The results show that the appropriate cutting slope and excavation steps, a good degree of compaction, the rational use of geosynthetic materials, the use of the use of high quality packing can make the new and old roadbed integrity, achieve good effect of design and construction and reduced the incidence of disease.

Abstract:

Cold recycle mixture with emulsified asphalt is a material which is economical, environmental and energy saving. Now it is widely applied to road recycling engineering, while there is no unified standard for its molding and curing methods. The orthogonal test shows that cold recycle mix with emulsified asphalt can get the better technical indicators after the molding and curing methods. At first, each side 50 times compaction after mixture putting into mold. Then put specimen side in the 60°C wind drying oven at least 40 hours. Next take the specimen out and compact each side 25 times immediately. Finally put specimen side on the ground at least 12 hours at room temperature, and then take the test-piece from the mold for test.

Abstract: In order to solve current airfield asphalt road surface high temperature performance evaluation index defective problem, through the hamburg wheel tracking test, general rutting test and uniaxial penetration to test three gradation mixture, and comprehensive analysis of dynamic stability, creep slope and the shear strength index. So suggest using dynamic stability and hamburg wheel tracking creep slope, rutting depth combination evaluation mixture at high temperature performance advantages and disadvantages.

Abstract: In practice of maintenance and repair project in the western plateau railway as the background, from maintenance and repair mechanism, detection method, line disease effect and other aspects, this paper studied the characteristics of the CWR in plateau permafrost region in-depth, analyzed the key problems of CWR maintenance and repair in permafrost region systematically, and put forward the corresponding solutions to meet the CWR maintenance requirements in plateau permafrost region.

Abstract: This paper analyzed temperature field and temperature stress of cement concrete pavement under periodic variable low temperature using finite element method modeling technique in ABAQUS. And discussed the effect of wind speed, surface thermal conductivity coefficient on temperature field. Cracking and warping at the joint of concrete panel was simulated to analyze pavement deformation and mechanical characteristics. Results show that at lower temperature, concrete face will appear horizontal longitudinal displacement, causing the appearance of cracking; and warping effect will appear at the concrete panel, leading to concrete pavement void. It is revealed that dowel bar has not occurred plastic deformation, that is, bending strength meets the requirements.

Abstract: The pressure on the wagon body is generated for stochastic vibration of train or vehicle. The value and variation of this dynamic pressure are great significance in the study of the fatigue strength of the wagon body. This paper reviews the various influencing factors of the pressure distribution and also summarizes its simulation and prediction method based on the sufficiently literature reading.

Abstract: Study on nanomodified asphalt is a hot and new topic in the field of pavement’s material research. Reviewed the application of nanomaterial and technology in asphalt pavement and elaborated the nanomodified asphalt’s composition. To make a clear understanding of nanomodified asphalt’s properties, it also analyzed the nanomodified asphalt’s formation mechanism. Based on the analysis of nanomodified asphalt, we put forward several most promising research direction in this field.