再生混凝土冻融作用下强度损伤研究

Study on strength damage of recycled concrete under freeze-thaw action

再生混凝土替代粗骨料具有重要的经济及生态价值。通过试验研究再生混凝土在压缩时的力学性能以及在冻融循环作用下的强度损伤。通过压缩试验,分析再生取代率和硅粉掺量对再生混凝土的抗压强度的变化影响;通过冻融循环试验,研究不同再生取代率和不同硅粉掺量对再生混凝土试件抗冻耐久性的变化规律。研究发现,当混凝土再生取代率为50%、硅粉掺量为9%时,试件的抗压强度和抗冻耐久性能最好。

Replacing coarse aggregate with recycled concrete has important economic and ecological value.The mechanical properties of recycled concrete under compression and the strength damage of recycled concrete under freeze-thaw cycles are studied.Through unconfined compression test,the influence of recycled replacement ratio and silica fume content on the compressive strength of recycled concrete was analyzed.With the freeze-thaw cycle test,the change law of frost resistance durability of recycled concrete specimens with different replacement ratio and different content of Silica fume was studied.It is found that the compressive strength and frost resistance of the specimens are the best when the concrete regeneration rate is 50%and the content of silica fume is 9%.