防腐涂层厚度对水泥砂浆抗硫酸盐侵蚀性能的影响

Influence of Anti-corrosion Coating Thickness on Sulfate Attack Resistance of Cement Mortars

摘要:

为进一步明确防腐涂层厚度对水泥基材料防护效果的影响，研究了不同厚度涂层的水泥砂浆在硫酸盐侵蚀下抗折强度的变化规律，并采用核磁共振、扫描电镜、X射线衍射仪等技术分析了水泥砂浆的侵蚀状态，结合涂层抗渗性及黏结强度，阐明了涂层厚度对水泥砂浆抗硫酸盐侵蚀性能的影响机理。结果表明：水泥砂浆的抗硫酸盐侵蚀性能随着涂层厚度的增大呈现先上升后下降的趋势；在本文试验条件下，当涂层厚度为90 μm时，水泥砂浆抗折强度损失率、表面损坏等级和孔隙劣化程度均最低，防腐涂层防护效果最佳。

Abstract:

To further clarify the influence of anti-corrosion coating thickness on the protective effect of cement-based materials， the variation regularity of flexural strength of cement mortars with different thicknesses under sulfate attack was investigated. The attack state of the cement mortars was analyzed by nuclear magnetic resonance， scanning electron microscopy， and X-Ray diffraction. Combined with impermeability and bond strength of the coatings， the influence mechanism of coating thickness on the sulfate attack resistance of cement mortars was elucidated. The results reveal that the sulfate attack resistance of coated cement mortars first increases and then decreases as the coating thickness increases. Under the experimental conditions of this study， the lowest flexural strength loss rate， surface damage grade， and pore deterioration degree are exhibited by the cement mortar with a coating thickness of 90 μm. The optimal protective effect is achieved by the anti-corrosion coating with a thickness of 90 μm.