纳米碳酸钙改性再生混凝土抗压性能研究

Research on the Compressive Properties of Recycled Concrete Modified by Nano-CaCo_(3)

以再生粗骨料取代率、纳米改性为主要影响因素,通过抗压试验及有限元方法分别探究纳米改性再生混凝土的宏观与细观力学性能。研究结果表明:混凝土抗压强度随再生粗骨料取代率增大而降低,纳米CaCO_(3)可以提高混凝土3 d、7 d、28 d强度,适宜掺量为1%;而通过细观分析得到纳米CaCO_(3)改性可加强砂浆和粗骨料砂浆界面过渡区,同时有限元计算得到的力学性能与试验结果较为吻合,可为工程应用提供理论依据。

Taking the substitution rate of recycled coarse aggregate and nano-modification as the main influencing factors,the macro-and micro-mechanical properties of nano-modified recycled concrete are studied by compressive test and finite element method respectively.The results show that:the compressive strength of concrete decreases with the increasing replacement rate of recycled coarse aggregate;nano-CaCO_(3) can improve the strength of concrete at 3 d,7 d and 28 d,and the suitable dosage is 1%;based on the finite element method,the finite element analysis shows that NC modification can strengthen the interface transition zone of mortar and coarse aggregate mortar,meanwhile,the mechanical properties obtained from the finite element calculations are in good agreement with the test results,which can provide a theoretical basis for engineering applications.