School of Civil Engineering, Changsha University of Science & Technology, Changsha 410114, China.
School of Traffic & Transportation Engineering, Changsha University of Science & Technology, Changsha 410114, China.
J Nanosci Nanotechnol. 2020 Aug 1;20(8):5117-5122. doi: 10.1166/jnn.2020.18493.
To explore the evolution of cracks in the pre-disintegrated carbonaceous mudstone, wetting-drying tests were carried out on nano-CaCO₃ modified pre-disintegrated carbonaceous mudstone samples. The samples were prepared with aqueous solutions of different pH values. Scanning electron microscopy (SEM) was performed to clarify the mechanism of crack evolution of pre-disintegrated carbonaceous mudstone modified by nano-CaCO₃. The results showed that development of shrinkage and cracks was basically divided into three stages, i.e., the gestation stage, the rapid development stage and the stable stage. For the samples without nano-CaCO₃, the final crack rates and pore sizes of samples with pH = 3 and pH = 11 were larger than corresponding values of the sample with pH= 7. Moreover, final crack rate and pore size significantly decreased with the addition of nano-CaCO₃ suggesting that nano-CaCO₃ can effectively improve cracking resistance of pre-disintegrated carbonaceous mudstone.
为了探究预崩解碳质泥岩中裂纹的演化规律，对纳米 CaCO₃ 改性的预崩解碳质泥岩样品进行了干湿循环试验。采用不同 pH 值的水溶液制备了样品。利用扫描电子显微镜（SEM）阐明了纳米 CaCO₃ 改性预崩解碳质泥岩裂纹演化的机理。结果表明，收缩和裂纹的发展基本上可分为三个阶段，即孕育阶段、快速发展阶段和稳定阶段。对于不含纳米 CaCO₃ 的样品，pH = 3 和 pH = 11 时的最终裂纹率和孔径大于 pH = 7 时的对应值。此外，随着纳米 CaCO₃ 的加入，最终裂纹率和孔径显著降低，表明纳米 CaCO₃ 可以有效提高预崩解碳质泥岩的抗裂性。
