Abstract: 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.

Key words: permeable material, iron tailings sand, nano-modified, epoxy resin, silane coupling agent, mechanical property, water permeability coefficient