Papers by Author: Biao Ma

Abstract: Using the finite element method, influences of vehicle load, subgrade fillings and compactness on the subgrade work zone were analyzed, of which the traffic load impacts most. Considering the traffic and mechanical character of the subgrade, it is determined that the appropriate subgrade work zone depth of rural highway is 1.0m. As a result, applying proper work zone depth plays an important role in the construction cost of rural highway.

Abstract: Directly mixing the PCM to asphalt mixture may adversely affect mixture performance. By the experiment of SEM, the diffusion-absorption circle testing and the DSC, the micro-morphology and the adsorption characteristics to PCM of four carriers and the thermal properties of the composite shape-stabilized phase change materials (CSPCM) were analyzed. The results showed that the activated carbon, the floating bead and the white carbon black have more developed porous structure. The white carbon black has the best effect on the adsorption of PCM. The shape-stabilized PCM prepared by the physical adsorption method has the leakage problem. The CSPCM with the white carbon black carrier has the best heat storage capacity. The white carbon black is the best carrier of PCM for asphalt mixture.

Abstract: It provides a new way to solve the worldwide the low-temperature cracking and high temperature rutting distresses of the asphalt pavement, by mixing the composite shape-stabilized phase change material (CSPCM) to asphalt mixture. The effect of CSPCM on the temperature of asphalt mixture is analyzed by the monotonic cooling test, the monotonic heating test and the outdoor simulating cycle test. The results of monotonic cooling and heating tests indicate that mixing CSPCM into asphalt mixture can increase the temperature of asphalt mixture during cooling process and decrease the temperature of asphalt mixture during heating process. It has a temperature damping effect as well. The results of outdoor simulation test shows that mixing CSPCM into asphalt mixture decreases the maximum temperature of the bottom of the specimen and increases the minimum temperature of the bottom of the specimen. It cannot change the critical temperature occurring time of the bottom of the specimen. The test results indicate that mixing CSPCM into asphalt mixture could actively adjust the working temperature of asphalt mixture, prolong the ideal temperature of asphalt mixture and improve asphalt mixture’s adaptability to the changing environment.

Abstract: Both the government and the firms are concerning about the development of cyclic economy for highway projects construction. However, the huge investment risks and technology spillover are primary obstacle for developing and research of energy saving and emission reduction. This paper introduces the theory of the dynamic game of complete information to analyze how the government provide sufficient subsidy and make preferential policy to promote the firms to do it for their own interests. According to the establishment of sub-game perfect Nash equilibrium under non-corporative conditions, it indicates clearly that the most effective measures to make sure the firms to develop cyclic economy is that the government should maintain the highest rate of subsidies to the first firm who is willing to developing the energy saving technology.

Abstract: Mixing the phase change material (PCM) into asphalt mixture could change the thermo physical properties of asphalt mixture. Asphalt mixture with PCM can remain in the ideal working temperature range for a relatively long time. However, the PCM easily leaks from asphalt mixture in the process of using. To solve this problem, the carrier-adsorbed packing method is applied to modify PCM in this paper. Different carriers and packaging materials are used to prepare three kinds of composite shape-stabilized phase change energy storage material (CPCM). Their microscopic characteristics and thermo physical properties are analyzed by scanning electron microscope and differential scanning calorimetry, respectively. The results show that the gel of silicon incompletely packed the macropores of activated carbon and the clustered silica, and the ethyl cellulose completely coated the clustered silica whose particle size increases and particle surface forms a compacted thin film. The phase transition temperature and latent heat of CPCM with silica are higher than CPCM with activated carbon. The PCM absorption of silica is greater than the PCM absorption of activated carbon. The mass fraction of CPCM packed by the EC is larger than the CPCM packed by the gel-sol method. The results indicate that the carrier-adsorbed packing method can effectively solve the problem of PCM leaking from asphalt mixture. The CPCM prepared with silica and ethyl cellulose is the most suitable for asphalt mixture.

Abstract: Concrete interlocking block pavement is characterized of preferred durability, easy construction and maintenance and low construction cost. It can be widely applied in the rural highway. Based with the project of rural highway in Tongchuan Shaanxi province, the paper studies the mechanism of interlocking blocks, design of the pavement, and construction technology for field application. After one year service for open traffic, the interlocking block pavement is shown to have fascinating economy and service performance for the rural road.

Abstract: Mixing the composite phase change material (CPCM) to asphalt mixture is a new way to solve the worldwide problem of the low-temperature cracking and high temperature rutting of the asphalt pavement. Asphalt mixture with CPCM can remain in the ideal working temperature range for a relatively long time. This paper analyzes the influence of the contents of CPCM on its road performance by laboratory testing. The study shows that mixing CPCM to asphalt mixture had little effect to the optimal asphalt content. For CPCM prepared by polymer shape-stabilized method, the high-temperature stability and the water stability of asphalt mixture increases firstly and then decreases the low-temperature anti-cracking stability decreases firstly and then increases with the increasing of CPCM. For CPCM prepared by carrier-adsorbed packaging process, the high-temperature stability decreases, low-temperature anti-cracking stability decreases firstly and then increases, the water stability increases firstly and then decreases with increasing of CPCM. The results indicate that CPCM has significant influences on its road performance. The optimal content of CPCM is around 0.3%.

Abstract: The application of Phase Change Material (PCM) to asphalt mixture can lighten the temperature-dependent disease of the asphalt pavement and improve the usability as well as extend the operating life of it. We choose agreeable PCM with comprehensive consideration to the technical requirement of its application in the construction industry and the characteristic of asphalt mixture. Through simulating temperature experiment, we make a conclusion that incorporate the carrier accompanied PCM into asphalt mixture can reduce the increasing rate and cooling rate of the mixture, which shows that PCM can put into use of adjusting the asphalt mixture operating temperature, softening the negative influence of ambient temperature variation on asphalt mixture.