掺量和VA含量对EVA改性沥青性能的影响

Study on Influence of Amount and VA Content on Performance of EVA Modified Asphalt

为探索乙烯-醋酸乙烯共聚物(EVA)的掺量和乙酸乙烯(VA)含量对沥青性能的影响规律,制备了5%和10%两种掺量的EVA改性沥青,且每种掺量下EVA改性剂中的VA含量分别为18%、25%和32%,对制备的改性沥青分别进行常规指标测试、布氏黏度测试、流变测试和接触角测试。结果表明:简单或短时间搅拌无法使EVA在沥青体系内分散均匀,EVA与沥青的相溶性受VA含量的影响较大;EVA的加入使得沥青针入度降低、软化点提高、延度下降,体系温度敏感性下降;高VA含量不利于提升体系高温稳定性和黏聚性。

In order to explore the influence of the amount of ethylene-vinyl acetate copolymer(EVA)and the content of vinyl acetate(VA)on the performance of asphalt,two kinds of asphalt modified with 5%and 10%of EVA were prepared.The content of VA in EVA modifiers was 18%,25%and 32%for each blending amount.Tests on conventional indicators,Brinell viscosity,rheology and contact angle were conducted on the prepared modified asphalt.The results show that simple or short-time stirring cannot make EVA uniformly dispersed in the asphalt system,and the compatibility between EVA and asphalt is greatly affected by the VA content;The addition of EVA reduces the penetration of asphalt,increases the softening point,decreases the ductility,and reduces the system s sensitivity to temperature;high VA content is not conducive to improving the stability at high temperature and cohesiveness of the system.