粉煤灰再生混凝土力学性能的试验研究

研究了再生粗骨料取代率和粉煤灰取代率对再生混凝土工作性能和力学性能的影响,并初步探讨了其影响机理。研究结果表明:再生粗骨料取代天然骨料为60%时,粉煤灰再生混凝土的抗压、抗折强度比基准粉煤灰混凝土低,但其强度降低值较小。粉煤灰的掺入,改善了再生混凝土的和易性,改善了水泥石与骨料的界面,显著提高了再生混凝土的抗折强度。再生粗骨料取代天然骨料为60%时,粉煤灰再生混凝土的3d抗折强度可达3.9MPa,28d抗折强度可达5.19MPa,粉煤灰再生混凝土可应用于水泥混凝土路面的快速修补工程中。

Experimental Study of Mechanic Performance of Fly Ash and Recycled Aggregate Concrete

It is investigated the influence of the rate of coarse aggregate replacement and the rate of fly ash replacement on mechanical property and workability of concrete,and the mechanism of action is researched at the preliminary step.The result indicated that,with 60% of coarse aggregate replacement,the compressive strength and flexural strength of recycled concrete with fly ash are little lower than the reference concrete of fly ash.The addition of fly ash improves the workability of concrete,ITZ,and obviously increase the flexural strength of recycled concrete.With 60% of coarse aggregate replacement,the flexural strength of recycled concrete with fly ash can reach 3.9MPa at 3 days,and can reach 5.19MPa at 28days,so the recycled concrete with fly ash can be applied in the rapid repair engineering of the cement concrete pavement.