不同水泥掺量泡沫沥青冷再生混合料宏细观结构性能研究

Study on macrostructure and properties of foamed asphalt cold recycled mixture with different cement contents

通过室内试验研究了水泥掺量对泡沫沥青冷再生混合料抗松散性能、高低温性能和水稳定性的影响,并对泡沫沥青冷再生混合料的微观结构及宏细观空隙结构进行了分析。结果表明,掺加适量水泥可提高泡沫沥青冷再生混合料的粘结性及整体强度、显著提高泡沫沥青冷再生混合料的水稳定性;水泥水化产物显著改变了泡沫沥青冷再生混合料的微观空隙结构,减小了平均孔径和最可几孔径,从而显著提高泡沫沥青冷再生混合料的抗冻性。但随着水泥掺量的增加,泡沫沥青冷再生混合料的低温抗裂性能出现峰值,建议水泥掺量不宜超过2.0%。

Based on laboratory experiments,the effects of cement content on the anti-loose performance,high and low temperature performance and water stability of foamed asphalt cold recycled mixture were studied.The microstructure and macroscopic pore structure of cement-based foamed asphalt cold recycled mixture were revealed.The results show that the addition of proper amount of cement improves the cohesiveness and overall strength of the foamed asphalt cold recycled mixture,and significantly improves the water stability of the foamed asphalt cold recycled mixture.The cement hydration product significantly changes the microscopic distribution of the foamed asphalt cold recycled mixture.The void structure reduces the average void diameter and the most porous diameter,thereby significantly enhancing the freeze-thaw durability of the foamed asphalt cold recycled mix.However,as the cement content increases,the low temperature crack resistance of the foamed asphalt cold recycled mixture peaks.It is recommended that the cement content should not exceed 2.0%.