| Asphalt pavement has become the mainstream road type due to its goodpavement and excellent road performance. With the increasing traffic volume andload, the road performance and service life has been affected by aging because ofenvironmental factors. UV-aging is an important element of asphalt aging, especialin west part of our country. Ultraviolet intensity is strong and the radiation time islong, UV-aging is a serious issue. Therefore, it is significant to improve the agingresistance of the asphalt binders in order to prolong the service life of asphaltpavements.This paper aims at manufacturing LDHs modified SBS asphalt and researchingthe properties of LDHs/SBS modified asphalt and asphalt mixtures, studying theinfluences of LDHs on the pavement performances and the aging resistance of themodified asphalt and asphalt mixture. These researches provide theoretical basis forthe application of the LDHs/SBS modified asphalt in the asphalt pavementengineering.LDHs/SBS modified asphalt can be made by double impeller stirrer with350r/min in165±10℃for2hours. Seen through the X-ray diffraction and opticalmicroscope, the structure of LDHs is dispersion in SBS instead of intercalation. Withthe addition of LDHs, softening point and viscosity value of LDHs/SBS modifiedasphalts increased, while both of ductility and penetration decreased, compared toSBS asphalts. Temperature sweep tests showed that the complex modulus andfatigue factor of LDHs/SBS modified asphalts was increasing, while phase anglewas decreasing with the introduction of LDHs. The results showed that LDHsimproved the high-temperature stability of the asphalt. Moreover，LDHs/SBS asphaltmixture volume performance has not been changed, as the increasing of LDHs,stability, splitting strength of mixture increased and flow value decreased. Hightemperature stability improved and water stability properties decreased after the firstincreases more than5%content. Low temperature performance and fatigue lifedecreased with the increase of LDHs, however, the reduction is within the prescribedscope of design with the content of less than6%. What`s more, studied the UV-aging of LDHs/SBS asphalt and mixture, theresult show that after UV-aging the changes of three major indexes of LDHs/SBS isless than that of SBS，and the AVI of LDHs/SBS is decreased with the addition ofLDHs. The complex modulus, fatigue factor and rutting factor of LDHs/SBSmodified asphalts ware increasing, while phase angle was decreasing with theintroduction of LDHs after UV-aging. The Infrared spectrum showed the agingdegree of LDHs/SBS modified asphalt is smaller than SBS. LDHs/SBS asphaltmixture air void and void in mineral aggregate increased where asphalt saturationdecreased after UV-aging. The stability of mixture decreased, splitting strength, hightemperature stability and water stability properties of mixture ware improved. Lowtemperature performance and fatigue life of LDHs/SBS mixture were superior toSBS mixture. It is indicated that LDHs can improved the UV-aging resistantperformance of mixture.Incorporation with LiPan highway engineering project, the LDHs/SBS asphaltroadbed construction. LDHs was mixed from the asphalt pump pool and the top ofasphalt horizontal tank in construction site. Manufacture the LDHs/SBS asphalt bythe asphalt shear transfer pump and the impeller in the asphalt horizontal tank.According the data of construction site and mixing station, LDHs/SBS asphaltmixture with good pavement and excellent road performance, paving smoothlywouldn’t affect the normal production and construction. |
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