功能性渗蓄生态建筑材料的制备及性能研究

为促进海绵城市建设及固体废弃物资源化,利用铜尾矿、膨润土为填充料,再生烧结砖作骨料,以水泥为胶凝材料,制备同时具有“吸、蓄、渗、净”等功能的渗蓄生态建筑材料。采用正交试验对材料配合比进行优化设计,并研究在最优配合比基础上该材料的植物生长及水质净化效果。试验结果表明:铜尾矿、膨润土用量分别为15.0%和7.5%,水灰比W/C取0.90时,材料28 d抗压强度＞4.0 MPa,渗透系数＞4.0 cm/s,吸水率＞21.0%;采用泥浆覆盖法培养出的碱茅和四季青效果较好,可分别作为水利工程和海绵城市建设的最优选择;经材料净化后,悬浮物(SS)、化学需氧量(COD)、总磷(TP)和氨氮(NH₃-N)等杂质浓度分别降低约53.3%,29.6%,51.9%,25.6%,且培养植被后对水溶性杂质的净化效果更强,经材料吸附的磷、氨氮等部分物质对植被生长更有利。

Preparation and Properties of Functional Eco-material

In the light of sponge city construction and solid waste resource utilization, we prepared ecological building material using copper mine tailings and bentonite as filler, recycled sintered bricks as aggregate, and cement as cementitious material. The material has functions of absorption, storage, infiltration and purification. We further optimized the mix proportion of the material through orthogonal experiment and investigated the plant growth and water purification effects of the material at optimum mix ratio. Results demonstrate that with a 15% and 7.5% dosage of copper mine tailings and bentonite, respectively, and a water cement ratio at 0.90, the functional eco-material boasts a 28-d compressive strength over 4.0 MPa, permeability coefficient greater than 4.0 cm/s, and water absorption more than 21.0%. The material also has good effect in cultivating Puccinellia distans Parl. and folium Ilex chinensis by mud mulching method, which can be used for water conservancy project and sponge city construction respectively. Filtered by the material, SS, COD, TP, and NH₃-N reduces by 53.3%, 29.6%, 51.9%, and 25.6%, respectively. The purification effect of the material after plant cultivation is stronger for water-soluble impurities. Theoretically, substances such as TP and NH₃-N adsorbed by the material are more beneficial to vegetation growth.