超热老化温度对浇注式改性沥青力学性能的影响规律

Influence Rule of Epithermal Aging Temperature on Mechanical Performance of Modified Gussasphalt

通过对4种超热老化温度下(190、210、230、250℃)浇注式改性沥青常规力学性能(软化点、针入度、延度)和流变力学性能的变化规律进行研究,研究结果表明:随着超热温度的提高,浇注式改性沥青低温和疲劳性能衰变明显,250℃时的低温延度只有190℃时的50%。若以劲度模量300 MPa时的开裂温度作为临界温度,250℃时的临界开裂温度比190℃时约高4℃。而随着超热温度的提高,改性沥青的高温性能则明显提高,车辙因子成倍数提高,因此改变超热温度对浇注式改性沥青力学性能影响显著。

The change regularities of conventional mechanical performances （softening point, penetration, ductility） and rheologieal mechanical performances of modified gussasphalt at 4 epithermal aging temperatures （190, 210, 230, 250 ℃ ） were studied. The results show that （1） the higher the epithermal aging temperature, the more obvious the low-temperature and fatigue performance decay of modified gussasphah; （2） the low temperature ductility at 250 ℃ is only one half of that at 190 ℃, and if taking the cracking temperature in 300 MPa stiffness modulus as critical temperature, the cracking temperature at 250 ℃ is 4 ℃ higher than that at 190 ℃; （3） with the rise of epithermal aging temperature, the high temperature performance of modified gussasphah noticeably increases and rutting factor increases several times, so the change of epithermal temperature has a noticeable influence on the mechanical performance of modified gussasphah.