Field cores from typical cracking locations were tested by the semi-circular bending test and the digital image correlation method to evaluate the anti-fatigue performance of different asphalt pavements. Test results ...Field cores from typical cracking locations were tested by the semi-circular bending test and the digital image correlation method to evaluate the anti-fatigue performance of different asphalt pavements. Test results were analyzed by different fatigue models. Causes of fatigue cracking for different pavement sections were determined by extraction and sieving test results. It is found that the ranking （from high to low） in terms of the anti-fatigue performance for field cores is the crumb rubber modified asphalt mixture, densegraded modified asphalt mixture, continuous graded asphalt treated base, gap-graded stone asphalt concrete, and half open-graded asphalt macadam. Compared with the half opengraded asphalt macadam, the fatigue life of the crumb rubber modified asphalt mixture improves by 2. 0 to 3. 8 times. Fatigue lives of different mixtures and distress ratios of actual pavements can be accurately predicted by the dissipated energy density ratio. Causes of fatigue cracking vary with mixture types.展开更多
In order to study the application of gyratory compaction molding method in emulsified asphalt cold recycled mixture and optimize the relevant technical parameters, the study was carried out according to splitting stre...In order to study the application of gyratory compaction molding method in emulsified asphalt cold recycled mixture and optimize the relevant technical parameters, the study was carried out according to splitting strength, stability and water stability test;the design of the experiment involved changing gyration number, emulsified asphalt and water content, molded specimen temperature and other factors to analyze the volume parameters, mechanical properties and water stability. The results show that both the maximum dry density and dry and wet splitting strength ratio(DWSSR) of emulsified asphalt cold reclaimed mixture are improved by the rotary compacting method, while the porosity and the optimal dosage of water are reduced. Furthermore, with the increase of compaction times, the porosity and splitting strength index both change exponentially. DWSSR and porosity are consistent with quadratic functions. The use of gyratory compaction for 70 times at 25 °C and the optimum dosage of emulsified asphalt can be determined based on the splitting strength ratio. The high-temperature stability and water damage resistance of the pavement can be improved by the use of rotary compacting method effectively, and the early strength and road performance are higher than the regulatory requirements.展开更多
To evaluate the effects of Crumb Rubber Modifiers (CRMS) on basic engineering properties (i.e. Marshall, tensile strength, and compressive strength) of stone matrix asphalt mixtures, the ASTM testing and procedures we...To evaluate the effects of Crumb Rubber Modifiers (CRMS) on basic engineering properties (i.e. Marshall, tensile strength, and compressive strength) of stone matrix asphalt mixtures, the ASTM testing and procedures were employed. Results of the evaluation were used to quantify the effect of CRM source and CRM content on engineering properties at testing temperatures of 25 ℃ and 60 ℃. Statistical models were developed, which represent the nature of effects on performance-related properties of stone matrix asphalt mixtures.展开更多
基金The National Natural Science Foundation of China(No.51308303)the Natural Science Foundation of Jiangsu Province(No.BK20130980)+1 种基金Qing Lan Project,the Practice Innovation Training Program Projects for the Jiangsu College Students(No.201410298024Z)the Scientific Innovation Research of College Graduates in Jiangsu Province(No.SJLX15_0418)
文摘Field cores from typical cracking locations were tested by the semi-circular bending test and the digital image correlation method to evaluate the anti-fatigue performance of different asphalt pavements. Test results were analyzed by different fatigue models. Causes of fatigue cracking for different pavement sections were determined by extraction and sieving test results. It is found that the ranking （from high to low） in terms of the anti-fatigue performance for field cores is the crumb rubber modified asphalt mixture, densegraded modified asphalt mixture, continuous graded asphalt treated base, gap-graded stone asphalt concrete, and half open-graded asphalt macadam. Compared with the half opengraded asphalt macadam, the fatigue life of the crumb rubber modified asphalt mixture improves by 2. 0 to 3. 8 times. Fatigue lives of different mixtures and distress ratios of actual pavements can be accurately predicted by the dissipated energy density ratio. Causes of fatigue cracking vary with mixture types.
基金Projects(51708048,51704040)supported by the National Natural Science Foundation of ChinaProject(17C0050)supported by the Scientific Research Project of Hunan Provincial Department of Education for General Scholars,China+1 种基金Project(kfj160103)supported by the Open Fund of State Engineering Laboratory of Highway Maintenance Technology(Changsha University of Science&Technology),ChinaProject supported by the Open Fund of Guangxi Key Lab of Road Structure and Materials,China
文摘In order to study the application of gyratory compaction molding method in emulsified asphalt cold recycled mixture and optimize the relevant technical parameters, the study was carried out according to splitting strength, stability and water stability test;the design of the experiment involved changing gyration number, emulsified asphalt and water content, molded specimen temperature and other factors to analyze the volume parameters, mechanical properties and water stability. The results show that both the maximum dry density and dry and wet splitting strength ratio(DWSSR) of emulsified asphalt cold reclaimed mixture are improved by the rotary compacting method, while the porosity and the optimal dosage of water are reduced. Furthermore, with the increase of compaction times, the porosity and splitting strength index both change exponentially. DWSSR and porosity are consistent with quadratic functions. The use of gyratory compaction for 70 times at 25 °C and the optimum dosage of emulsified asphalt can be determined based on the splitting strength ratio. The high-temperature stability and water damage resistance of the pavement can be improved by the use of rotary compacting method effectively, and the early strength and road performance are higher than the regulatory requirements.
文摘To evaluate the effects of Crumb Rubber Modifiers (CRMS) on basic engineering properties (i.e. Marshall, tensile strength, and compressive strength) of stone matrix asphalt mixtures, the ASTM testing and procedures were employed. Results of the evaluation were used to quantify the effect of CRM source and CRM content on engineering properties at testing temperatures of 25 ℃ and 60 ℃. Statistical models were developed, which represent the nature of effects on performance-related properties of stone matrix asphalt mixtures.
