This work modified recycled aggregates (RAs) by soaking them in a nano-silica (NS) suspension and evaluated the modification effects on recycled aggregate concrete (RAC). Firstly, different soaking times were studied based on the surface microhardness and the penetration depth of NS particles in the RA. Secondly, mechanical properties (e.g., compressive strength and microhardness of interfacial transition zones) and durability properties (e.g., steel corrosion and corrosion-induced cracking) were tested. The 1-h soaking modification was selected as the optimal soaking time. The nano-modification improved the protection of steel and the resistance to corrosion-induced cracking, which was believed to be related to the improvement of the ITZ properties according to the microhardness test results.

这项工作通过将再生骨料（RAs）浸泡在纳米二氧化硅（NS）悬浮液中进行了改性，并评估了其对再生骨料混凝土（RAC）的改性效果。首先，根据表面显微硬度和NS颗粒在RA中的渗透深度研究了不同的浸泡时间。其次，测试了机械性能（例如，界面过渡区的抗压强度和显微硬度）和耐用性（例如，钢腐蚀和腐蚀引起的开裂）。选择1-h浸泡时间作为最佳浸泡时间。根据显微硬度测试结果，纳米改性改善了钢的保护性和耐腐蚀诱发的开裂性，这被认为与改善ITZ性能有关。