铁尾矿砂基环氧树脂透水材料力学性能及界面特性研究

利用固体废弃物制备透水材料是海绵城市发展新方向,而力学性能差成为固废基透水材料应用的难点之一。为解决该问题,设计了一类用铁尾矿砂作为骨料,环氧树脂作为胶凝材料的聚合物透水材料,研究了环氧树脂含量对透水材料力学性能和透水性能的影响,并探讨了纳米SiO₂、TiO₂、Al₂O₃和硅烷偶联剂KH-560等有机-无机材料对透水材料力学性能的影响。结果表明:当环氧树脂质量分数为6%时,可以得到兼顾力学性能和透水性能的透水材料,抗压、抗折强度和透水速率分别为17.5 MPa、5.3 MPa和1.12 mm/s;同时,当纳米SiO₂、TiO₂、Al₂O₃的添加量分别为环氧树脂的3%、4%、4%(质量分数)时,对透水材料力学性能的提升分别为33.1%、30.5%、28.6%,其原因是纳米粒子在透水材料受压过程中会吸收树脂基体中的部分能量,抑制或消除树脂中微裂纹的扩散;当硅烷偶联剂KH-560的添加量为环氧树脂的0.9%(质量分数)时,透水材料的强度可提升36.5%。SEM和FTIR分析表明,硅烷偶联剂KH-560对改善铁尾矿砂与环氧树脂界面具有显著作用。该研究对研发高性能的固废基透水材料具有重要意义。

Mechanical Properties and Interface Characteristics of Iron Tailings Sand-Based Epoxy Resin Permeable Material

Manufacturing of permeable materials via solid waste is a potential direction in the development of sponge cities. However, the poor mechanical properties become one of the key difficulties for the application of permeable materials. In this study, polymer permeable material combined with iron tailings sand as aggregate and epoxy resin as cementitious material was designed. The effects of epoxy resin content on the mechanical properties and water permeability of permeable materials were investigated. Additionally, the effects of different organic-inorganic admixtures such as nano-SiO₂, TiO₂, Al₂O₃ and silane coupling agent KH-560 on the mechanical properties were discussed. The results show that when the mass fraction of epoxy resin is 6%, a high performance permeable material is obtained, the compressive strength, flexural strength and water permeability rates are 17.5 MPa, 5.3 MPa and 1.12 mm/s, respectively. When the addition amount of nano-SiO₂, TiO₂, Al₂O₃ is 3%, 4%, 4% (mass fraction) of epoxy resin, the improvement of the compressive strength is 33.1%, 30.5%, 28.6%, respectively. The reason is concluded that nanoparticles absorb part of the energy in the resin matrix during the compression of the permeable material, inhibiting or eliminating the diffusion of microcracks in the resin. When the addition amount of the silane coupling agent KH-560 is 0.9% of epoxy resin, the compressive strength increased by 36.5%.SEM and FTIR analysis show that silane coupling agent KH-560 has a significant effect on improving the interface between iron tailings sand and epoxy resins. This research provides significant guidance to development of high-performance solid waste-based permeable materials.