【摘要】 磷酸镁水泥因具有快速硬化、早强等特点,常被作为混凝土的修补材料,但其突出的脆性问题限制了它在修补工程中的应用。本研究采用玻璃纤维对磷酸钾镁水泥进行增韧,探索了玻璃纤维对磷酸镁水泥力学性能的改善情况,并运用扫描电镜、X射线衍射仪对水化产物及微观形貌进行分析。研究结果表明,玻璃纤维可以明显提高磷酸钾镁水泥的力学性能,且随着玻璃纤维掺量的增加(低于1.2%)磷酸钾镁水泥的抗折、抗压强度不断增长;但当掺量超过1.2%时,玻璃纤维对磷酸钾镁水泥抗折强度改善作用减低,并对抗压强度产生不利影响。随着纤维长度的增长,磷酸钾镁水泥抗折强度逐渐降低,但对抗压强度影响较小,当纤维长度为6mm时,抗折强度提高,有利于此胶凝材料水化产物的生成及后期强度的发展。经硅烷偶联剂的混合液进行表面改性预处理的玻璃纤维更有利于提高纤维与磷酸镁水泥的结合力。更多还原

【Abstract】 Magnesium phosphate cement is commonly used as repairing material in concrete construction,due to its outstanding properties such as rapid hardening and early strength.However,its outstanding brittleness problem restricted its application.Glass fiber was used in this work to toughen the magnesium potassium phosphate cement(MKPC),and the effect of fiber glass on the mechanical properties of MKPC was investigated,coupled with X-ray diffraction(XRD)and Scanning electron microscope(SEM)method for phase identification and microstructure analysis.The results show that,the flexural and compressive strength of MKPC increased with incorporation of the glass fiber.The flexural and compressive strength increased with the increasing dosages of the glass fiber(less than 1.2%).However,the improvement on the flexural strength by the glass fiber deceased and adverse effect was observed on the compressive strength,with the dosages of the glass fiber more than 1.2%.The flexural strength of MKPC decreased with raising the length of the glass fiber,but subtle effect on its compressive strength.It is favorable for the flexural strength with a length of6 mm of the glass fiber.Short glass fiber could contribute to improve the hydration of MKPC,advancing the production of hydration and its late-stage mechanical properties.The bond strength between the glass fiber and MKPC was strengthened with the glass fiber treated by silane coupling agent on the surface.更多还原