纳米SiO2和聚丙烯纤维对煤矸石二灰混合料改性试验研究

为了研究纳米SiO₂和聚丙烯纤维对煤矸石二灰混合料力学性能及水稳定性能的影响,通过无侧限抗压强度试验、劈裂试验测得各组试件改性前后强度值,并对干湿循环后试件质量、强度值及声发射特性进行分析。结果表明:纳米SiO₂可以提高煤矸石二灰混合料的抗压强度,掺量为2.5%(质量分数)时效果最佳;同时加入纳米SiO₂和聚丙烯纤维可以进一步提升混合料的力学性能,掺加2.5%纳米SiO₂和0.15%(体积分数)聚丙烯纤维时煤矸石二灰混合料力学性能最好;掺加2.5%纳米SiO₂和0.10%(体积分数)聚丙烯纤维的煤矸石二灰混合料水稳定性能最佳。

ModificationofCoalGangueLime-FlyAshMixtureby Nano-SiO2andPolypropyleneFiber

In order to study the effects of nano-SiO₂ and polypropylene fiber on the mechanical properties and water stability of coal gangue lime-fly ash mixture, the strength values of each specimen before and after modification were measured by unconfined compressive strength test and splitting test, and the quality difference, strength value and acoustic emission characteristics of the specimens after dry-wet cycle were analyzed. The results show that nano-SiO₂ improves the compressive strength of the mixture, and the improvement effect is the best when the mass content is 2.5%. Adding nano-SiO₂ and polypropylene fiber at the same time further improve the mechanical properties of the mixture.The mechanical properties of coal gangue lime-fly ash mixture are the best when 2.5% nano-SiO₂ and 0.15% (volume fraction) polypropylene fiber were added. It is found that the water stability of coal gangue lime-fly ash mixture mixed with 2.5% nano-SiO₂ and 0.10% (volume fraction) polypropylene fiber is the best.