乳化沥青／地质聚合物复合材料的制备及力学性能研究

Study on Preparation and Mechanical Properties of Emulsified Asphalt/Geopolymer Composite Materials

本文研究了乳化沥青/地质聚合物复合材料的不同成型工艺、不同养护温度以及不同乳化沥青掺量对材料性能的影响。以复合材料的抗压强度、抗折强度和弹性模量为指标,并采用了SEM、XRD对试件断面以及样品进行了分析。结果表明复合材料最佳养护温为60℃,随着乳化沥青掺量的提高,复合材料的抗压强度有所降低,抗折强度先小幅升高,后下降并趋于一个平稳值,材料的弹性模量降低明显;通过断裂曲线,结合SEM、XRD,对复合材料的成型工艺和断裂机理进行了简单分析,可发现复合材料的断裂模式由原来的脆性断裂变为假塑性断裂模式。结果表明该材料具有凝结硬化时间合适、力学性能好,制备的复合材料最高抗压强度超过普通沥青混凝土、抗折强度可达17.9 MPa、弹性模量最低可至400 MPa。

This paper examines discrepant molding processes, different curing temperatures and admixture amount of emulsified asphalt that influence the composite properties of the Emulsified asphalt/Geopolymer composite materials. It selects the compressive strength, bending strength and modulus of elasticity as the indexes and analyzes the fracture surface of test specimens and samples in terms of scanning electron microscope （SEM） and X-ray powder diffraction （XRD）. According to the results, the best curing temperature of the composite materials is 60 ℃. The compressive strength of the composite materials decreases as emulsified asphalt admixture amount increases. Meanwhile, the bending strength undergoes a slight up and then tends to go down to a stationary value; the elastic modulus goes down conspicuously. It can thus infer a fracture mode that has changed from brittle fracture to fake plastic fracture mode through analyzing the molding process and fracture mechanism of the composite materials with regards to SEM, XRD and fracture curves. In conclusion, it turns out that this material contains the quality of suitable setting time and good mechanical performance. The highest compressive strength of composite materials overweighs the strength of bituminous concrete. Its bending strength can reach 17.9 MPa, elastic modulus of this material can be as low as 400 MPa.