In view of the disadvantage that the mechanical properties of cement-based composites can be significantly reduced by incorporating waste rubber powder in situ, the surface modification methods of the original rubber ...In view of the disadvantage that the mechanical properties of cement-based composites can be significantly reduced by incorporating waste rubber powder in situ, the surface modification methods of the original rubber powder by coupling agent KH560, sodium hydroxide, polyvinyl alcohol (PVA), methyl hydroxyethyl cellulose ether (MHEC) and tetraethyl orthosilicate (TEOS) as precursors were adopted respectively. The modification of waste rubber powder was studied by Change rate of mortar strength of cement-based composite mortar mixed with waste rubber powder. The results show that the hybrid modification method using tetraethyl orthosilicate as precursor has better ef-fect. When 5 phr ethyl orthosilicate is added, the compressive strength and flexural strength of cement-based composite mortar can be increased by 31.7% and 28%. Scanning electron microscopy (SEM) results show that the surface of waste rubber powder with good modification effect has many pro-trusions and flake-like porous structures which are beneficial to its bonding with cement-based materials.展开更多
玄武岩纤维(BF)合理的长度及掺量对水泥基复合材料的工作性能及力学性能有显著影响。试验对比研究了长度为3、6、9 mm BF,当掺量为0.2%、0.4%、0.6%、0.8%时,BF水泥基复合材料的流动度及抗折、抗压性能的变化,并探讨了试块在7 d、14 d...玄武岩纤维(BF)合理的长度及掺量对水泥基复合材料的工作性能及力学性能有显著影响。试验对比研究了长度为3、6、9 mm BF,当掺量为0.2%、0.4%、0.6%、0.8%时,BF水泥基复合材料的流动度及抗折、抗压性能的变化,并探讨了试块在7 d、14 d热稳定性能的变化。结果表明,BF越长,掺量越高,BF水泥基复合材料流动度显著下降。与空白试块的流动度267 mm相比,掺0.8%9 mm BF水泥基材料的流动度下降至207 mm。水泥基中加入合理掺量与长度的BF时,能显著提高水泥基复合材料的抗拉、抗压强度。当长度为9 mm BF掺量小于0.4%时,BF水泥基复合材料的抗折、抗压强度综合性能最优。此外,BF水泥基复合材料在7 d和14 d具有类似的热降解行为,且14 d试块的热稳定性优于7 d试块的热稳定性。同样龄期下,与空白试块相比,BF水泥基试块的热稳定性明显提升。展开更多
文摘In view of the disadvantage that the mechanical properties of cement-based composites can be significantly reduced by incorporating waste rubber powder in situ, the surface modification methods of the original rubber powder by coupling agent KH560, sodium hydroxide, polyvinyl alcohol (PVA), methyl hydroxyethyl cellulose ether (MHEC) and tetraethyl orthosilicate (TEOS) as precursors were adopted respectively. The modification of waste rubber powder was studied by Change rate of mortar strength of cement-based composite mortar mixed with waste rubber powder. The results show that the hybrid modification method using tetraethyl orthosilicate as precursor has better ef-fect. When 5 phr ethyl orthosilicate is added, the compressive strength and flexural strength of cement-based composite mortar can be increased by 31.7% and 28%. Scanning electron microscopy (SEM) results show that the surface of waste rubber powder with good modification effect has many pro-trusions and flake-like porous structures which are beneficial to its bonding with cement-based materials.
文摘玄武岩纤维(BF)合理的长度及掺量对水泥基复合材料的工作性能及力学性能有显著影响。试验对比研究了长度为3、6、9 mm BF,当掺量为0.2%、0.4%、0.6%、0.8%时,BF水泥基复合材料的流动度及抗折、抗压性能的变化,并探讨了试块在7 d、14 d热稳定性能的变化。结果表明,BF越长,掺量越高,BF水泥基复合材料流动度显著下降。与空白试块的流动度267 mm相比,掺0.8%9 mm BF水泥基材料的流动度下降至207 mm。水泥基中加入合理掺量与长度的BF时,能显著提高水泥基复合材料的抗拉、抗压强度。当长度为9 mm BF掺量小于0.4%时,BF水泥基复合材料的抗折、抗压强度综合性能最优。此外,BF水泥基复合材料在7 d和14 d具有类似的热降解行为,且14 d试块的热稳定性优于7 d试块的热稳定性。同样龄期下,与空白试块相比,BF水泥基试块的热稳定性明显提升。
