Applied Mechanics and Materials Vols. 361-363

Abstract: In order to realize a comprehensive effect assessment of highway construction of different levels, the thesis builds up a system of evaluating indicators in a meso-level, which consists of three criteria—land saving amount, function and service level and comprehensive return of land usage. Moreover, it nails down the standard value of the land saving index, and determines practical value of each index by taking the actual situation of HengShui-DaMing section in DaQing-GuangZhou expressway into consideration, then carries out non-dimensional treatment to the index and builds a comprehensive index model by employing the multi-factor evaluation method based on entropy method empowerment. Multi-factor composite index model is a feasible approach to assess the land saving effect of a certain highway construction project, thus realizing the definition and comparative evaluation of land saving level.

Abstract: Removed due to plagiarism.

Abstract: This paper used one kind of organic additive LEADCAP to reduce the compacting temperature of SBS WMA mixture, and compared the WMA mixture compacted by superpave gyratory compactor (SGC) with HMA mixture to determine the compacting temperature of WMA mixture. Rutting test, low temperature bending test, freeze-thaw indirect tension test, Hamburg Wheel-Track test and dynamic modulus were carried out to evaluate the road performance of WMA mixed with LEASCAP. The test result showed that the WMA mixed with LEADCAP had well performed high temperature stability, low temperature stability, water stability, rutting cracking resistance, and high dynamic modulus, the compacting temperature were 127 °C, and affectively reduced the compacting temperature of SBS WMA mixture.

Abstract: By adding Sasobit, DAT and BLT additives to reach the purpose of hot mix asphalt mixture construction temperature decreasing, achieve energy conservation and environmental protection. With an AC-13 SBS modified hot mix asphalt as reference, the high and low temperature performance and water stability of three energy-saving and environment-protecting road materials are evaluated through laboratory tests. The results show that compared with HMA, all the three kinds of energy-saving and environment-protecting road materials exhibited a significant increase by 8%-15% in high temperature stability. While the low temperature cracking resistance and anti-water damage performance of Sasobit mixture were decreased somewhat, little changes in these two aspects of the performance of the other two materials. Finally, analyses the economic benefits, and provide the basis for the choice of asphalt mixture cooling additives.

Abstract: Through research on precast assembling structural design and construction technology in cement concrete pavement maintenance engineering, this paper brings forward reasonable size for precast assembling slab in cement concrete pavement maintenance engineering to improve original precast assembling construction technology and brings forward effective improvement measures for original construction technical difficulties. And simultaneously, through making a comparison of socioeconomic benefits among precast assembling maintenance mode, cast-in-place ordinary concrete maintenance mode , cast-in-place early-strength concrete maintenance mode and cast-in-place reinforced concrete, uses that precast assembling maintenance technology is a cement concrete pavement quick maintenance technology with extremely high performance price ratio.

Abstract: Both thermal stress and load stress, which are caused by temperature change and traffic loading, are important parameters used in the analysis of the new asphalt pavement design. In order to study the stress of asphalt pavement of lean concrete base, first of all, threedimension finite element model of the asphalt pavement of lean concrete base is established. The main objectives of the paper are investigated. One is calculation for stress of asphalt surface, and the other is calculation for stress of lean concrete base. The results show that load stress of lean concrete base increases quickly with the increase of load. Thermal stress of lean concrete base increases with the increase of thickness of base. Asphalt surface is in the state of compression. Maximum shearing stress decreases with the increase of thickness of asphalt surface.

Abstract: Vibration and noise reduction was the trend of ballastless track, however, evaluation of different types of damping effect of the track was not easy to achieve. The orbit of the traditional vertical displacement of the components, to evaluate the damping effect of the acceleration was not accurate when the difference between the track structure larger. From the principle of energy conservation, the flexibility to select a long pillow, long pillow vertical, orbital plate of three ballastless track fragments, respectively, without the establishment of a vehicle - track couplin model, the vertical acceleration, the vertical track of the various components of displacement, acceleration, maximum kinetic energy was calculated out when train speed was 250km/h by numerical simulation methods. By analyzing the relationship between their body vertical acceleration and found that the largest track the existence of kinetic energy correlation between the changes in, made with the greatest kinetic energy damping effect as the track of one of the evaluation criteria, and it was easy to implement.

Abstract: At present designers take little account of the different requirements of pavement performance when determining the adding ratio of lignin fibers in Chinese SMA mixture. Basing on the high temperature performance the article studied the optimum fiber content of SMA-13 mixture through comparative tests of performance. First aiming at SMA-13 mixture with different fiber contents, the mix proportions were designed and asphalt contents were verified. Then the effect of fiber content on high temperature performance was indicated through three kinds of interrelated performance tests. At last other pavement performances of SMA-13 mixture were verified. Based on the test results, an optimum fiber content of 0.33% is recommended for the lignin fibers used in this SMA-13 mixture, with which mixture poses the best high temperature performance.

Abstract: In order to analyze load stress of roller compacted concrete base of asphalt pavement, first of all, threedimension finite element model of the flexible pavement is established. The main objectives of the paper are investigated. One is calculation for stress of roller compacted concrete base in asphalt pavement, and the other is analysis for relationship between load stress of roller compacted concrete base and parameters, such as thickness, modulus. The results show that stress, which is caused by load that is located in the middle of longitudinal joint of roller compacted concrete base of asphalt pavement. Maximum load stress decrease, decrease and increase respectively with increase of the surfaces thickness, bases thickness and ratio of bases modulus to foundations modulus.

Abstract: The stability evaluation of highway near a goaf is a key problem in highway construction projects. The goal of this research is to analyze the surface deformation of the highway No.108 in Baoshui area. Both Probability Integral Method (PIM) and Finite Difference Method (FDM) are used and compared to deal with this problem. The main aspects of this research consist of surface subsidence calculation and prediction of surface residual deformation. The results calculated by probability integral method and finite difference method are mainly in agreement,and they are in accord with surface deformation observation results of some sections. So these two kinds of method are proven to be effective in dealing this problem. Moreover, the surface residual deformation was predicted by using numerical simulation based on FLAC^3D. To ensure the highway No.108 security, backfill grouting should be carried out in the areas where collapse pits and ground fissure are found near the highway.