基于Burgers模型的温拌胶粉沥青胶浆低温流变特性

Low-Temperature Rheological Properties of Warm-Mixed Crumb Rubber Asphalt Mortar Based on Burgers Model

摘要:

为了研究热氧老化作用对SDYK表面活性剂型温拌胶粉改性沥青胶浆（SWCRM）和EM降黏剂型温拌胶粉改性沥青胶浆（EWCRM）低温流变特性的影响，对热氧老化后的SWCRM、EWCRM以及热拌胶粉改性沥青胶浆（HCRM）进行弯曲梁流变（BBR）试验.以劲度模量（S）与蠕变速率敏感指数（m）的比值S/m及基于Burgers模型的松弛时间（λ）和低温综合柔量参数（J_c）为指标，分析老化作用对3种沥青胶浆低温流变特性的影响.结果表明：3种沥青胶浆热氧老化后的低温流变性能均减弱；采用Burgers模型研究沥青胶浆的低温流变性能是合理的；J_c能很好地描述沥青胶浆的低温流变性能；在-18 ℃时， EWCRM的S/m值和J_c值相较于HCRM分别下降了12.72%、8.58%，SWCRM的S/m值和J_c值相较于HCRM分别下降了30.09%、20.71%，说明温拌剂的加入会改善沥青胶浆的低温流变性能，且SDYK的改善效果优于EM.

Abstract:

In order to study the effect of thermo-oxidative aging on the low temperature rheological properties of SDYK surfactant warm mix crumb rubber modified asphalt mortar （SWCRM） and EM viscosity reducer warm mix crumb rubber modified asphalt mortar（EWCRM）， the bending beam rheological （BBR） test was carried out on SWCRM， EWCRM and hot mix crumb rubber modified asphalt mortar （HCRM） after thermo-oxidative aging. The effects of aging on the low temperature rheological properties of three kinds of asphalt mortar were analyzed by using S/m（S is stiffness modulus， m is creep rate sensitirity index）， relaxation time λ based on Burgers model and low temperature comprehe compliance parameter J_c as indexes. The results show that the low-temperature rheological properties of the three asphalt mortars are weakened after thermal oxidative aging. It is reasonable to study the low temperature rheological properties of asphalt mortar by Burgers model. J_c can well describe the low-temperature rheological properties of asphalt mortar. At -18 ℃， the S/m value and J_c value of EWCRM decreases by 12.72 % and 8.58 % compared with HCRM. And the S/m value and J_c value of SWCRM decrease by 30.09% and 20.71 %. It follows that the addition of warm mix agent will improve the low temperature rheological properties of asphalt mortar， and SDYK is better than EM.