【摘要】 为了研究纳米TiO₂掺量（0、0.4%、0.8%、1.2%）和再生粗骨料取代率（25%、50%、75%）对再生混凝土抗碳化性能的影响，对各组再生混凝土试件进行了快速碳化试验，测得了再生混凝土在不同碳化龄期（3、7、14、28 d）的碳化深度，并对不同纳米TiO₂掺量和再生粗骨料取代率下的再生混凝土碳化深度进行了计算与分析。结果表明：再生混凝土碳化深度随碳化时间和再生粗骨料取代率的增大而增大；纳米TiO₂的掺入能有效提高再生混凝土的抗碳化性能，且不同再生粗骨料取代率下，纳米TiO₂的最优掺量均为0.8%。对试验所得数据进行回归分析，建立了纳米TiO₂再生混凝土碳化深度预测模型。对实测值与模型计算值进行了误差分析，可知该模型能较好地预测纳米TiO₂再生混凝土的碳化深度。更多还原

【Abstract】 In order to study the influence of nano-TiO₂ content（0, 0.4%, 0.8%, 1.2%） and recycled coarse aggregate（RCA） replacement ratio（25%, 50%, 75%） on the anti-carbonation performance of recycled aggregate concrete（RAC）, the rapid carbonation test was carried out. The carbonation depth of RAC at different carbonation ages（3 d, 7 d, 14 d, 28 d） was measured, and the effects of different nano-TiO₂ contents and RCA replacement ratios were analyzed. The test results show that the carbonation depth of RAC increases with the increase of carbonation time and the replacement ratio of RCA. The incorporation of nano-TiO₂ can effectively improve the anti-carbonation performance of RAC, and the optimal nano-TiO₂ content is 0.8% regardless of the replacement ratio of RCA. Regression analysis was carried out on the data obtained from the test, and the carbonation depth prediction model of NT/RAC was established. Through the error analysis between the measured value and the calculated value of the prediction model, it can be seen that the model can well predict the carbonation depth of NT/RAC.更多还原