硅藻土改性沥青在冻融循环下的基本性能及微观研究

Basic properties and microcosmic study of diatomite modified asphalt under freeze-thaw cycles

为了研究冻融循环作用对硅藻土改性沥青基本性能的影响,通过沥青的常规三大指标对硅藻土改性沥青、3次冻融循环后以及8次冻融循环后的硅藻土改性沥青进行试验,并利用电镜扫描和原子力显微镜进行对其进行观测。结果表明:经冻融循环作用后的硅藻土改性沥青感温性能下降幅度明显,对基质沥青的低温抗裂性影响较大,对硅藻土改性沥青的低温抗裂性影响较小,对硅藻土改性沥青的高温稳定性有所降低;电镜扫描结果表明由于冻融循环作用硅藻土颗粒吸形成较大的聚集体,从而间接的影响改性沥青的性能;原子力显微镜结果表明硅藻土改性沥青由于冻融循环导致结构被破坏,导致了硅藻土改性沥青的性能有所下降。

In order to study the effect of freeze-thaw cycle on the basic properties of diatomite modified asphalt,the diatomite modified asphalt,diatomite modified asphalt after 3 freeze-thaw cycles and diatomite modified asphalt after 8 freeze-thaw cycles were tested and observed by electron microscopy and atomic force microscopy.The results show that the temperature drop of diatomite modified asphalt after freeze-thaw cycle has a significant effect on the low temperature crack resistance of matrix asphalt,which has little effect on the low temperature crack resistance of diatomite modified asphalt.The stability of diatomite modified asphalt has been reduced.The results of electron microscopy showed that the diatomite particles formed a larger aggregate due to the freeze-thaw cycle,which indirectly affected the properties of the modified asphalt.The results of atomic force microscopy showed that the diatomite modified asphalt was damaged due to the freeze-thaw cycle The performance of diatomite modified asphalt has declined.