SBS改性沥青热储存稳定性评价

Evaluation of Heat Storage Stability of SBS Modified Asphalt

采用8种成品SBS改性沥青,根据《公路工程沥青及沥青混合料试验规程》(JTJ 052-2000)中T0661的方法,分别对其进行热储存离析试验;并且采用AR-2000型动态剪切流变仪对不同品牌的成品SBS改性沥青及热储存离析试验上、下部试样进行动态剪切试验,以获取SBS改性沥青动态力学温度谱。试验表明,仅以离析试验上下部软化点差值小于2.5℃来评价SBS改性沥青储存稳定性是不全面的,SBS改性沥青在储存中会产生软化点的升高或衰减,这些同样会导致沥青的使用性能的不稳定性。在温度扫描下损耗因子tanδ是否出现平台区,即是否形成空间网络结构与SBS改性沥青的储存动力稳定性的好坏没有必然的联系。

Eight kinds of SBS modified asphalts are studied comparatively with the T0661 method described in ＂Standard test methods of asphalt and bituminous asphalt mixtures for highway engineering＂（JTJ052-2000） and every kinds SBS modified asphalt and hot storage segregation tests top and bottom sample are taken dynamic sheer test with Dynamic Sheer Reheometer AR-2000 in order to get the dynamic mechanics temperature spectrum of SBS modified asphalt.Based on the analysis of experiment data,it is found that evaluating the storage stability only by the standard that △t is no more than 2.5℃ would be insufficient and unreasonable.The SBS modified asphalt in store will produce softening point rise or attenuation,and these will also lead to using properties instability.The platform area of loss factor tanδ whether appearing or not is not necessarily associated with the SBS modified asphalt storage stability stand or fall.