Limits...
Investigation of Low Heat Accumulation Asphalt Mixture and Its Impact on Urban Heat Environment.

Xie J, Yang Z, Liang L - PLoS ONE (2015)

Bottom Line: The results also revealed that, compared to asphalt with 0% far-infrared radiant content, the asphalt material with a certain ratio of far-infrared radiation material had higher stability at high and low temperatures as well as good water absorption capacity.The Marshall stability of the specimen mixed with 6% far-infrared radiant was higher by 12.2% and had a residual stability of up to 98.9%.The friction coefficient of the asphalt mixtures with 6% and 12% far-infrared radiation material increased by 17.7% and 26.9%, respectively.

View Article: PubMed Central - PubMed

Affiliation: Department of Civil Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China.

ABSTRACT
This study is focused on investigating the effectiveness of low heat accumulation asphalt mixture and its impact on the urban heat environment. Infrared radiation experiments showed that the temperature of the asphalt mixture decreased with the increase in far-infrared radiant material. The results also revealed that, compared to asphalt with 0% far-infrared radiant content, the asphalt material with a certain ratio of far-infrared radiation material had higher stability at high and low temperatures as well as good water absorption capacity. The Marshall stability of the specimen mixed with 6% far-infrared radiant was higher by 12.2% and had a residual stability of up to 98.9%. Moreover, the low-temperature splitting tensile strength of the asphalt mixture with 6% far-infrared radiation material increased by 21.3%. The friction coefficient of the asphalt mixtures with 6% and 12% far-infrared radiation material increased by 17.7% and 26.9%, respectively.

No MeSH data available.


Related in: MedlinePlus

Relationship between pendulum value and infrared powder content.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4519290&req=5

pone.0133829.g007: Relationship between pendulum value and infrared powder content.

Mentions: The rut-simulation test was used to determine the longitudinal coefficient of friction of the test specimens. The test was carried out disregarding the impact of the external environment, size of the main road, road surface friction coefficient of roughness, and frictional properties of materials related to the asphalt. At the macro level, when the surface roughness was higher, the surface texture and friction coefficient were also high. At the micro level, a higher mix of textures in the aggregate resulted in a stronger asphalt mastic adhesion and higher friction coefficient. Fig 7 shows the fitted relationship between the longitudinal friction coefficient and the infrared powder content. It can be seen that the selected graded asphalt friction coefficient reached 0.735 (% pendulum value), which is higher than the road index value of 0.54. The friction coefficient was enhanced by the addition of infrared powder to the asphalt, increasing by 17.7% and 26.9% at 6% and 12% infrared powder contents, respectively, compared to the value at 0% infrared powder content. The reasons for the slight decrease in the depth of the surface structure and increase in the friction coefficient could be the following: 1. The asphalt mastic viscosity increases after the alkali treatment of the infrared powder, which increases the friction; 2. The strong performance of the infrared absorption powder dispersed in the asphalt ensures that the inside surface of the mixture does not overflow, which is beneficial to its anti-slide lasting stability properties. It was also found in a previous study that the alkaline treatment improves the adhesion of the asphalt material and that mineral aggregate in the asphalt surface produces chemical components, which rearrange to form the structure of the asphalt, increasing the viscosity and the friction coefficient [22]. Hence, the performance and long-term stability of the pavement are improved.


Investigation of Low Heat Accumulation Asphalt Mixture and Its Impact on Urban Heat Environment.

Xie J, Yang Z, Liang L - PLoS ONE (2015)

Relationship between pendulum value and infrared powder content.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4519290&req=5

pone.0133829.g007: Relationship between pendulum value and infrared powder content.
Mentions: The rut-simulation test was used to determine the longitudinal coefficient of friction of the test specimens. The test was carried out disregarding the impact of the external environment, size of the main road, road surface friction coefficient of roughness, and frictional properties of materials related to the asphalt. At the macro level, when the surface roughness was higher, the surface texture and friction coefficient were also high. At the micro level, a higher mix of textures in the aggregate resulted in a stronger asphalt mastic adhesion and higher friction coefficient. Fig 7 shows the fitted relationship between the longitudinal friction coefficient and the infrared powder content. It can be seen that the selected graded asphalt friction coefficient reached 0.735 (% pendulum value), which is higher than the road index value of 0.54. The friction coefficient was enhanced by the addition of infrared powder to the asphalt, increasing by 17.7% and 26.9% at 6% and 12% infrared powder contents, respectively, compared to the value at 0% infrared powder content. The reasons for the slight decrease in the depth of the surface structure and increase in the friction coefficient could be the following: 1. The asphalt mastic viscosity increases after the alkali treatment of the infrared powder, which increases the friction; 2. The strong performance of the infrared absorption powder dispersed in the asphalt ensures that the inside surface of the mixture does not overflow, which is beneficial to its anti-slide lasting stability properties. It was also found in a previous study that the alkaline treatment improves the adhesion of the asphalt material and that mineral aggregate in the asphalt surface produces chemical components, which rearrange to form the structure of the asphalt, increasing the viscosity and the friction coefficient [22]. Hence, the performance and long-term stability of the pavement are improved.

Bottom Line: The results also revealed that, compared to asphalt with 0% far-infrared radiant content, the asphalt material with a certain ratio of far-infrared radiation material had higher stability at high and low temperatures as well as good water absorption capacity.The Marshall stability of the specimen mixed with 6% far-infrared radiant was higher by 12.2% and had a residual stability of up to 98.9%.The friction coefficient of the asphalt mixtures with 6% and 12% far-infrared radiation material increased by 17.7% and 26.9%, respectively.

View Article: PubMed Central - PubMed

Affiliation: Department of Civil Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China.

ABSTRACT
This study is focused on investigating the effectiveness of low heat accumulation asphalt mixture and its impact on the urban heat environment. Infrared radiation experiments showed that the temperature of the asphalt mixture decreased with the increase in far-infrared radiant material. The results also revealed that, compared to asphalt with 0% far-infrared radiant content, the asphalt material with a certain ratio of far-infrared radiation material had higher stability at high and low temperatures as well as good water absorption capacity. The Marshall stability of the specimen mixed with 6% far-infrared radiant was higher by 12.2% and had a residual stability of up to 98.9%. Moreover, the low-temperature splitting tensile strength of the asphalt mixture with 6% far-infrared radiation material increased by 21.3%. The friction coefficient of the asphalt mixtures with 6% and 12% far-infrared radiation material increased by 17.7% and 26.9%, respectively.

No MeSH data available.


Related in: MedlinePlus