高吸水性树脂(SAP)对沥青黏度及力学性能的影响  

Effect of super absorbent polymer(SAP)on viscosity and mechanical properties of asphalt

作　　者：吴昊[1] 孙雨轩 宋卫民[1] 詹易群 WU Hao;SUN Yuxuan;SONG Weimin;ZHAN Yiqun(School of Civil Engineering,Central South University,Changsha 410075,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075

出　　处：《中南大学学报（自然科学版）》2022年第10期3948-3958,共11页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(51778638,52008405)。

摘　　要：高吸水树脂(SAP)具有极强的吸水和保水能力,吸水后的SAP在沥青中具有发泡降黏的作用。为了探究吸水后的SAP对沥青胶浆的降黏效果,采用不同掺量的SAP等体积替代矿粉。首先,采用红外光谱试验分析SAP与沥青的相互作用机理;然后,探究SAP替代不同掺量的矿粉(10%,20%,30%和40%,体积分数)并预先吸收不同质量的水时沥青胶浆黏度的变化情况,在此基础上进行动态剪切蠕变试验以及低温弯曲试验探究SAP改性沥青的高、低温性能;最后,通过沥青与集料黏附性试验探究SAP对沥青胶浆与集料黏附性的影响。研究结果表明:SAP与沥青以物理共混状态存在;用吸水后的SAP替代矿粉有很好的降黏效果,但SAP替代量超过30%、吸水量超过SAP自身质量的3倍后对降黏的作用不再明显;当SAP等体积替代矿粉不超过10%时,沥青胶浆的高温稳定性能有一定提升,低温抗裂性能有所下降,但当SAP等体积替代矿粉超过10%时,沥青胶浆的高温稳定性能有所下降,下降幅度均低于15%,低温抗裂性能有所提升;SAP的加入不会对沥青胶浆与集料之间的黏附性产生影响。Super absorbent polymer(SAP)has strong water absorption and retention capacities,and water-absorbing SAP has the function of foaming and reducing viscosity of asphalt.In order to explore the viscosity reduction effect of SAP after water absorption on asphalt mastic,SAP was used with different dosages to replace hydrated lime in equal volume.Firstly,infrared spectrum test was conducted to analyze the interaction mechanism between SAP and asphalt.Then,viscosity test was performed to explore volume fraction of the asphalt mastic viscosity when SAP substituted different amounts of hydrated lime(10%,20%,30%,40%,volume function)and pre-absorbed different amounts of water.On this basis,dynamic shear creep test and low temperature bending test were carried out to verify the high and low temperature behaviors of SAP-modified asphalt.Finally,the adhesion test was conducted to explore the effect of SAP on the adhesion between asphalt mastic and aggregate.The results show that SAP and asphalt exist in a physical blending state.The replacement of hydrated lime with water absorbing SAP has good effect on viscosity reduction,but the viscosity reduction is no longer obvious when the replacement amount is larger than 30%and the water absorption is more than three times of the mass of SAP.The high temperature stability performance of asphalt mortar is improved when the equal volume of SAP is not more than 10%of the hydrated lime,and the low temperature cracking performance is reduced.However,the high temperature stability performance decreases after 10%SAP inclusion,and the decrease rate is less than 15%.The low temperature cracking performance is promoted.The inclusion of SAP has no effect on the adhesion between asphalt mastic and aggregate.

关 键 词：高吸水树脂(SAP) 降黏作用 流变性能 低温性能 

分 类 号：U414[交通运输工程—道路与铁道工程]