内掺渗透结晶材料对水泥混凝土耐久性影响研究进展

Research progress on influence of internally incorporated permeable crystalline materials on durability of cement concrete

摘要

【目的】水泥混凝土的耐久性对水利工程结构健康服役具有重要意义。渗透结晶材料通过沉淀/络合沉淀反应对水泥混凝土具有优异的增密抗渗作用，能够提升混凝土的耐久性以延长使用寿命。【方法】在介绍渗透结晶材料的组成与作用机理的基础上，分别从抗渗性、抗氯离子渗透性能、抗硫酸盐侵蚀性能、抗裂性、抗冻性和裂缝自修复性能等方面总结了内掺渗透结晶材料对混凝土耐久性的影响，探讨了渗透结晶材料的工程应用现状，并提出了渗透结晶材料未来研究发展的建议。【结果】结果表明：渗透结晶材料可以通过促进生成结晶物质，细化水泥混凝土的孔隙结构，从而提升抗渗性和抗氯离子侵蚀性能。在硫酸盐环境中，渗透结晶材料和硫酸根对钙离子具有抢夺作用，减少了石膏和钙矾石生成，降低了混凝土的侵蚀破坏。渗透结晶材料对混凝土的抗裂性和抗冻性也具有提升效果。目前渗透结晶材料在工程中的应用以外涂为主，内掺应用较少。【结论】根据当前研究现状，内掺渗透结晶材料对混凝土的体积变形和抗碳化性能的研究较少，未来可对此进行系统性研究。混凝土开裂是导致耐久性劣化的重要因素，可建立裂缝与耐久性之间的关系和模型，评价裂缝自修复对耐久性的影响。水泥混凝土的耐久性研究需要长期的试验，未来可以结合数据驱动手段实现结果预测，从而提高试验效率。

Abstract

[Objective] The durability of cement concrete is crucial for the health and service life of hydraulic engineering structures. Permeable crystalline materials can effectively densify the cement concrete and enhance its impermeability through precipitation/complexation-precipitation reactions, thereby improving concrete durability and extending its service life. [Methods] Based on the introduction to the composition and action mechanisms of permeable crystalline materials, the influence of internally incorporated permeable crystalline materials on concrete durability is summarized in terms of impermeability, chloride ion penetration resistance, sulfate erosion resistance, crack resistance, frost resistance, and self-healing performance of cracks. Current engineering application status of permeable crystalline materials is discussed, and recommendations for future research and development are proposed. [Results] The results show that permeable crystalline materials can enhance concrete impermeability and chloride ion erosion resistance by promoting the formation ofcrystalline substances and refining the pore structure of cement concrete. In sulfate environments, permeable crystalline materials compete with sulfate ions for calcium ions, reducing the formation of gypsum and ettringite and consequently mitigating concrete erosion damage. Additionally, these materials enhance crack resistance and frost resistance of concrete. Currently, the application of permeable crystalline materials in engineering is primarily external coating, while internally incorporated applications remain relatively rare. [Conclusion] Based on the current research status, studies on the influence of internally incorporated permeable crystalline materials on the volume deformation and carbonation resistance of concrete are scarce, indicating the need for systematic studies in the future. Concrete cracking is an important factor in durability deterioration. The relationships and models between cracks and durability can be established to evaluate the influence of crack self-healing on durability. Research on the durability of cement concrete requires long-term testing. In the future, data-driven method can be combined to achieve result prediction and thus improve testing efficiency.

关键词

水泥混凝土 / 渗透结晶材料 / 耐久性 / 工程应用 / 孔隙结构 / 抗渗性 / 影响因素 / 裂缝自修复性能

Key words

cement concrete / permeable crystalline materials / durability / engineering application / pore structure / impermeability / influencing factors / self-healing performance of cracks

基金资助

国家自然科学基金项目(52378280)