Study On Road Performance And Low Temperature Characteristics Of Basalt Fiber SMA-13

With the rapid development of China’s economy,the number of expressways opened to traffic has continued to rise.The highways have successively issued a variety of disease problems.The problem of rutting in the early stage of highway construction is relatively serious,resulting in the consideration of anti-rutting performance when selecting the pavement structure and pavement materials.However,there is insufficient research on the performance of pavement materials under low temperature environment.In particular,seasonally frozen areas have large temperature differences.When asphalt pavements have a low temperature or a large temperature difference,low-temperature cracks may occur due to the nature of the materials.Cracks not only affect the comfort of driving,but also seriously affect the service life of the pavement structure.Many scholars at home and abroad have conducted extensive research showing that the addition of high-performance fiber materials in the asphalt mixture can significantly improve the performance of the asphalt mixture in high-temperature and low-temperature environments.In recent years,chopped basalt fiber has attracted much attention due to its excellent performance,but domestically Foreign scholars have no systematic research on the low temperature performance of basalt fiber to asphalt mixture.With reference to relevant research,this paper focuses on the road performance and low-temperature characteristics of basalt fiber SMA.This article combines the Jilin Provincial Transportation Science and Technology Project "Damage characteristics and mechanism analysis of basalt fiber asphalt concrete under coupling of water and temperature".In the related research foundation of the research group,Firstly,the effect of basalt fiber on the physical properties of SMA asphalt mixture was studied.then the road performance test was adopted.High-temperature creep tests were performed to analyze the influence of basalt fiber on its viscoelastic properties,and the performance of the mixture was analyzed by the model.Finally,the low-temperature characteristics of basalt fiber asphalt mixture were comprehensively evaluated by low temperature bending test,low temperature splitting test,low temperature shrinkage coefficient,low temperature relaxation modulus and freeze-off temperature of the mixture.Relying on scientific research projects,trial road sections were laid.The specific work carried out in this paper is as follows:1.According to previous research of the research group,it is shown that the best performance is obtained when the basalt fiber length is 6mm and the fiber content is 0.4% in BF-SMA-13.Under the premise of maintaining the same porosity,the differences in grading and oil-cement ratio between BF-SMA-13 and lignin fiber SMA-13 were analyzed.The road performance of BF-SMA-13 at room temperature and high temperature was evaluated by water stability test,rutting test,high temperature uniaxial compression creep test and indirect tensile dynamic modulus test.2.In order to evaluate the mechanical properties of basalt fiber SMA-13 at low temperatures,trabecular bending tests at low temperatures from-30 to 10°C and low-temperature splitting tests were performed.It shows that basalt fiber can increase the strength and stiffness modulus of asphalt mixture at low temperature.The low temperature shrinkage coefficient test shows that the basalt fiber SMA-13 has a low coefficient of low temperature shrinkage.The trabecular low temperature relaxation test was performed at 0°C,and the low temperature relaxation modulus-time curve of BF-SMA-13 was obtained through the conversion relationship between creep compliance and relaxation modulus.Basalt fiber can increase the stress relaxation rate of the mixture and shorten the stress relaxation time.3.Through The Thermal Stress Restrained Specimen Test(TSRST),it was found that BF-SMA-13 had a lower freeze-off temperature,lower conversion point temperature and higher freeze-break stress.and was consistent with the results of relevant basic low-temperature tests.The Thermal TSRST results are consistent with the results of the relevant basic low-temperature test.Considering the low temperature shrinkage coefficient,splitting tensile stiffness modulus,splitting tensile strength and low temperature relaxation modulus of the mixture,Estimating Cracking Temperature of BF-SMA-13 Asphalt Pavement Using Temperature Stress Prediction Models Proposed by Hills and Brein4.Relying on scientific research projects,laying BF-SMA-13 test section on Changshuang Highway.BF-SMA-13 has no special requirements for production and construction machinery,and easy to construct.Through construction quality inspection and one-year tracking visit,it can be seen that BF-SMA-13 asphalt pavement has good road performance.