基于MSCR与测力延度试验的阻燃改性沥青高低温性能评价

Evaluation of High and Low Temperature Performance of Flame-retardant Modified Asphalt Based on MSCR and Force Ductility Test

为了评价阻燃SBS改性沥青的高温抗车辙性能,制备了七种包含不同阻燃剂不同掺量的SBS改性沥青,采用不同温度下多重应力蠕变恢复试验测试改性沥青在蠕变加载过程中的应力响应特征,以0.1和3.2 kPa两种应力水平下的不可恢复蠕变柔量J_(nr)和蠕变恢复百分率R作为阻燃改性沥青的高温抗车辙性能评价指标.为了评价阻燃SBS改性沥青的低温抗裂性能,采用测力延度试验分析阻燃改性沥青的拉伸特性及拉伸变化机理,提取拉伸柔量f、韧性比R作为阻燃改性沥青的低温抗裂性能评价指标.结果表明:添加14%有机阻燃剂AP428的SBS改性沥青的平均回复率最大,随温度改变量最小;添加14%有机阻燃剂APA428的SBS改性沥青的韧性比最大;无添加的SBS改性沥青的拉伸柔量最小.综上所述,应选择阻燃剂的种类为有机阻燃剂AP428,适宜掺量为沥青质量的14%.

In order to evaluate the high-temperature rutting resistance of flame retardant SBS modified asphalt,seven kinds of SBS modified asphalt with different flame retardants and different content were prepared.The stress response characteristics of modified asphalt during creep loading were tested by multiple stress creep recovery tests at different temperatures.The unrecoverable creep compliance Jnr and creep recovery percentage R under two stress levels of 0.1 and 3.2kPa were used as evaluation indexes of high temperature rutting resistance of flame retardant modified asphalt.In order to evaluate the low-temperature crack resistance of flame-retardant SBS modified asphalt,the tensile characteristics and tensile change mechanism of flame-retardant SBS modified asphalt were analyzed by force ductility test,and the tensile compliance F and toughness ratio R were extracted as the evaluation indexes of low-temperature crack resistance of flame-retardant modified asphalt.The results show that the average recovery rate of SBS modified asphalt with 14% organic flame retardant AP428 is the highest,and the change with temperature is the smallest.The toughness ratio of SBS modified asphalt with 14% organic flame retardant APA428 is the highest.The tensile compliance of SBS modified asphalt without addition is the smallest.The type of flame retardant should be selected as organic flame retardant AP428,and the appropriate dosage is 14% of the asphalt mass.