WER-SBR复合改性活性乳化沥青性能研究

丁苯橡胶(SBR)活性乳化沥青可以活化旧路面的老化沥青,但是存在高温稳定性差以及黏附性不足等问题。为解决SBR活性乳化沥青性能上的不足,使用水性环氧树脂(WER)对其进行复合改性,通过修正低温蒸发法获取蒸发残留物,分析不同掺量WER对SBR活性乳化沥青基本物理性能、黏附性、流变性能、低温蠕变性能以及还原性的影响。结果表明:掺入WER之后,SBR活性乳化沥青的针入度大幅下降,软化点显著提高,延度下降;WER能够显著提高SBR活性乳化沥青的高温稳定性,但对其低温延展性有负面影响;SBR活性乳化沥青的黏附性显著增强;复合剪切模量(G^*)、车辙因子(G^*/sin δ)随WER掺量的增加不断提高,相位角(δ)随WER掺量的增加不断下降,表明高温抗车辙性能得到改善;劲度模量(S)和蠕变速率(M)则随着WER掺量增加分别呈增大和降低趋势;WER的掺入不影响SBR活性乳化沥青的还原性。根据试验数据,WER掺量应控制在10%~15%(质量分数)。

Research on Performance of WER-SBR Composite Modified Active Emulsified Asphalt

Styrene butadiene rubber (SBR) active emulsified asphalt can activate aged asphalt of old pavement. However, the engineering application is limited due to its poor high-temperature stability and insufficient adhesion. To solve the performance shortcomings of SBR active emulsified asphalt performance, waterborne epoxy resin (WER) was used for composite modification. The evaporation residue was obtained by the modified low-temperature evaporation method. The effects of WER dosage on the basic physical properties, adhesion, dynamic rheological properties, low-temperature creep properties and reducibility of SBR active emulsified asphalt were analyzed. The results show that with incorporation of WER, the penetration of SBR active emulsified asphalt decreases significantly, the softening point increases significantly, but the ductility decreases. WER can significantly improve the high-temperature stability of SBR active emulsified asphalt, but has an adverse impact on its low-temperature ductility properties. In addition, WER significantly enhances the adhesion of SBR active emulsified asphalt. The complex shear modulus (G^*) and rutting factor (G^*/sin δ) increase, while phase angle (δ) decreases with the increase of WER dosage, implying that the high-temperature rutting resistance of SBR active emulsified asphalt is improved. Furthermore, with the increase of WER dosage, the stiffness modulus (S) and the creep rate (M) of SBR active emulsified asphalt show an increasing and decreasing trend, respectively. The incorporation of WER has little effect on the reducibility of SBR active emulsified asphalt. Based on the experimental results, the dosage of WER should be controlled in 10%~15% (mass fraction).