摘要
采用标准试验方法,研究锂渣掺量(0、10%、20%、30%)及再生粗骨料取代率(30%、50%、70%、100%)对预拌掺锂渣再生混凝土立方体抗压—劈裂抗拉强度的影响规律。结果表明,掺入适量锂渣,尤其在后期,锂渣能够与水泥水化产物发生二次水化反应,对再生混凝土的强度有一定提升,但掺入过多,则会产生反作用。再生粗骨料最佳取代率在50%左右。若取代率过大,由于再生骨料存在自身缺陷,会对强度产生较大负影响。通过试验数据及回归分析,拟合出预拌掺锂渣再生混凝土劈裂抗拉强度与立方体抗压强度之间的关系式。经对比发现,计算值与试验结果契合度较高。
The influence of lithium slag content(0,10%,20%,30%)and recycled coarse aggregate replacement rate(30%,50%,70%,100%)on the cube compressive strength and splitting tensile strength of recycled concrete with pre-mixed lithium slag was studied by standard test method.The results show that when lithium slag is added,especially in later stage,lithium slag can react with cement hydration products for two times,and the strength of recycled concrete will be improved.However,too much incorporation will produce counteraction.The optimum replacement rate of recycled coarse aggregate is about 50%.If the substitution rate is too large,the regenerated aggregate has its own defects,which will have a greater negative impact on the strength.Through experimental data and regression analysis,the relationship between splitting tensile strength and cube compressive strength of recycled concrete mixed with lithium slag is fitted,and it is found that the agreement between the calculated value and the test result is higher.
引文
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