干湿循环条件下建筑垃圾再生材料的抗变形能力研究

Study on the Deformation Resistance of Recycled Construction Materialsunder Dry-wet Cycles

依托某城市快速路工程建设,研究建筑垃圾用于路基材料的干湿循环特性,并结合工程中涉及的筑路材料和特性,研究干湿循环条件下建筑垃圾再生碎石的最大粒径及在水泥改性条件下对抗变形能力的影响。研究结果表明:随着干湿循环次数增加,抗变形能力逐渐减弱;随着最大粒径增加,再生碎石产生的累计塑性应变逐渐减少,且碎石较多的试样对干湿循环次数更敏感;水泥改良后的再生碎石,能有效地避免孔隙粒径和数量扩张,相对未经改良的再生碎石,水泥改良能降低28.1%~54.2%的累积塑性应变;表明水泥的掺入,能为再生碎石形成具有一定强度的网状结构,增加内部结构的稳定性,提高在干湿循环作用下的抗变形能力,可用于建筑垃圾筑路材料的改性。

Relying on an urban expressway construction project,it explores the dry-wet cycle characteristics of construction waste used for roadbed materials.And in combined with the construction materials involved in the projectand the material characteristics,it studies the maximum particle size of recycled aggregates from construction waste under dry-wet cycles and the effect of cement modificationon theresistance to deformation.The results of the research show that the deformation resistance gradually weakens with the increase in the number of dry-wet cycles;the cumulative plastic strain of recycled aggregates gradually decreases with the increase in the maximum particle size,and the specimens with more aggregates are more sensitive to the number of dry-wet cycles.In addition,the cement-modified recycled aggregates can effectively prevent the expansion of the pore size and number.Data shows that cement modification can reduce the cumulative plastic strain by 28.1%-54.2%.The results also suggest that the incorporation of cement can lead to a mesh structure with a specific strength of recycled aggregates,thereby enhancing the internal stability of recycled aggregates to show higher resistance to deformation in a dry-wet cycle environment.So cement can be used for the modification of construction waste into road construction materials.