Zhang Tingting, Zhang Jingbin, Zhao Yang, Ai Hongmei
Faculty of Infrastructure Engineering, Dalian University of Technology, Dalian 116024, China.
Materials (Basel). 2023 Oct 12;16(20):6668. doi: 10.3390/ma16206668.
The magnesium silicate hydrate system (MgO-SiO-HO) possesses issues such as susceptibility to cracking, brittleness, and poor volumetric stability, which hinder its development and practical use in engineering applications. This study aimed to enhance the properties of the MgO-SiO-HO system by incorporating glass fiber as a reinforcing material. The mechanical properties, shrinkage properties, and properties during accelerated aging were tested at different content levels of glass fiber. Additionally, the reaction mechanism and microscopic morphology were characterized using microscopic testing methods. The results revealed that the addition of glass fiber improved the mechanical properties of the MgO-SiO-HO system; meanwhile, with an increase in fiber content, the mechanical properties showed an initial increase followed by a decreasing trend. With a glass fiber content of 0.6%, the system exhibited a flexural strength of 7.9 MPa at 28 d, a compressive strength of 42.5 MPa at 28 d, and a 27.2% increase in splitting tensile strength compared to the control group. At a fiber content of 0.9%, the flexural toughness steadily increased, reaching a maximum value of 2.238 N·m, which is 5.41 times greater than that of the control group. Moreover, the incorporation of glass fiber effectively inhibited the shrinkage of the MgO-SiO-HO system. Accelerated aging experiments confirmed that the glass fiber in the MgO-SiO-HO system did not undergo significant deterioration or corrosion, thereby maintaining long-term stability. These findings have important theoretical and practical significance for the application and development of the MgO-SiO-HO system.
水合硅酸镁体系（MgO-SiO-H₂O）存在诸如易开裂、脆性大以及体积稳定性差等问题，这些问题阻碍了其在工程应用中的发展和实际应用。本研究旨在通过加入玻璃纤维作为增强材料来改善MgO-SiO-H₂O体系的性能。在不同玻璃纤维含量水平下测试了其力学性能、收缩性能以及加速老化过程中的性能。此外，使用微观测试方法对反应机理和微观形态进行了表征。结果表明，加入玻璃纤维改善了MgO-SiO-H₂O体系的力学性能；同时，随着纤维含量的增加，力学性能呈现出先增加后下降的趋势。当玻璃纤维含量为0.6%时，该体系在28 d时的抗折强度为7.9 MPa，抗压强度为42.5 MPa，与对照组相比劈裂抗拉强度提高了27.2%。当纤维含量为0.9%时，抗折韧性稳步增加，达到最大值2.238 N·m，是对照组的5.41倍。此外，加入玻璃纤维有效地抑制了MgO-SiO-H₂O体系的收缩。加速老化实验证实，MgO-SiO-H₂O体系中的玻璃纤维没有发生明显劣化或腐蚀，从而保持了长期稳定性。这些发现对MgO-SiO-H₂O体系的应用和发展具有重要的理论和实际意义。
