This research aims at analysing the mechanical performance of concrete with recycled aggregates from concrete pavements. First, the characteristics of various natural and recycled aggregates used in the concrete were thoroughly analysed. The composition of the recycled aggregates was determined and several physical and chemical tests of the aggregates were performed. In order to evaluate the mechanical performance of recycled concrete, cube compressive strength and flexural tensile strength tests were performed. The effect of recycled aggregates on the strength of recycled concrete is related to the strength of recycled aggregates, the strength of natural aggregates, and the strength of old concrete. The strength of recycled concrete decreases with increasing water-cement ratio. However, due to the water absorption of the recycled aggregate, it has a certain inhibitory effect on the strength reduction. As the replacement rate of recycled aggregates increases, the optimal sand ratio decreases. The sand ratio is controlled between 32% and 38%, which is ideal for recycled concrete. With the increase of fly ash content, the 7 d strength of recycled concrete has decreased to some extent, but the 28 d strength has been slightly improved. In addition, for compressive strength and flexural tensile strength, the optimal content of fly ash is different.

中文翻译：

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混凝土路面再生骨料制成的混凝土的机械性能

这项研究旨在分析混凝土路面再生骨料的混凝土力学性能。首先，对用于混凝土的各种天然和再生骨料的特性进行了全面分析。确定了回收骨料的组成，并对骨料进行了一些物理和化学测试。为了评估再生混凝土的机械性能，进行了立方抗压强度和弯曲抗拉强度测试。再生骨料对再生混凝土强度的影响与再生骨料的强度，天然骨料的强度和旧混凝土的强度有关。再生混凝土的强度随着水灰比的增加而降低。但是，由于回收骨料的吸水性，对强度降低有一定的抑制作用。随着再生骨料替代率的提高，最佳砂比降低。砂比控制在32％至38％之间，非常适合再生混凝土。随着粉煤灰含量的增加，再生混凝土的7 d强度有所降低，但28 d强度有所提高。另外，对于抗压强度和弯曲抗拉强度，粉煤灰的最佳含量不同。但28 d强度有所提高。另外，对于抗压强度和弯曲抗拉强度，粉煤灰的最佳含量不同。但28 d强度有所提高。另外，对于抗压强度和弯曲抗拉强度，粉煤灰的最佳含量不同。