ABSTRACT

Mechanistic and microstructural characteristics of roller-compacted concrete (RCC) produced from recycled asphalt pavement (RAP) and geopolymer cement binder (GPC) were evaluated and compared with mixtures produced from ordinary Portland cement (OPC). It was found that RCC using geopolymer binder exhibited higher unconfined compressive strength, modulus of elasticity, and flexural strength as compared to the mixture containing ordinary Portland cement. It was also discovered that the mechanical properties of the developed concrete depend on mixture constituents: sodium hydroxide molarity, the ratio of sodium silicate to sodium hydroxide, curing temperature, and gradation of RAP. The experimental results showed that RCC using geopolymer binder exhibited compressive strength, modulus of elasticity, and flexural strength in the range of 8.4–21.1 MPa, 18.3–35.0 GPa, and 2.9–4.1 MPa, respectively. On the other hand, RCC using 12% OPC presented similar mechanical strengths of 13.2 MPa, 32.8 GPa, and 3.32 MPa, respectively. Regression analysis was also performed to establish the relationship between mechanical characteristics and various mixture constituents. Morphological and microstructural analysis proved the formation of geo-polymeric compounds. Based on the mechanistic characteristics, the developed roller-compacted RAP-Geopolymer concrete could be used as a strong pavement base in composite pavement system or wearing course of low volume roads.

摘要

对由再生沥青路面 (RAP) 和地质聚合物水泥粘合剂 (GPC) 生产的碾压混凝土 (RCC) 的力学和微观结构特性进行了评估，并与由普通硅酸盐水泥 (OPC) 生产的混合物进行了比较。结果发现，与含有普通硅酸盐水泥的混合物相比，使用地质聚合物粘合剂的 RCC 表现出更高的无侧限抗压强度、弹性模量和弯曲强度。还发现，开发的混凝土的机械性能取决于混合物成分：氢氧化钠摩尔浓度、硅酸钠与氢氧化钠的比率、固化温度和 RAP 的级配。实验结果表明，使用地质聚合物粘合剂的 RCC 的抗压强度、弹性模量和抗弯强度在 8.4-21.1 MPa 范围内，分别为 18.3–35.0 GPa 和 2.9–4.1 MPa。另一方面，使用 12% OPC 的 RCC 表现出相似的机械强度，分别为 13.2 MPa、32.8 GPa 和 3.32 MPa。还进行了回归分析以建立机械特性与各种混合物成分之间的关​​系。形态学和微观结构分析证明了地质聚合物的形成。基于力学特性，开发的碾压 RAP-地质聚合物混凝土可用作复合路面系统或低容量道路磨耗层的强路面基层。还进行了回归分析以建立机械特性与各种混合物成分之间的关​​系。形态学和微观结构分析证明了地质聚合物的形成。基于力学特性，开发的碾压 RAP-地质聚合物混凝土可用作复合路面系统或低容量道路磨耗层的强路面基层。还进行了回归分析以建立机械特性与各种混合物成分之间的关​​系。形态学和微观结构分析证明了地质聚合物的形成。基于力学特性，开发的碾压 RAP-地质聚合物混凝土可用作复合路面系统或低容量道路磨耗层的强路面基层。