【摘要】 为明确棉花秸秆在地聚物中的作用,对8组棉秆粉煤灰基地聚物(C-FAG)试样进行了物理性能和力学性能试验,并用扫描电镜(SEM)观察C-FAG断面。分析了养护条件、棉秆处理方式、棉秆掺量对地聚物密度、吸水率、表面情况、受压破坏形态、断面特征、抗压和抗折强度的影响。结果表明:掺入棉秆对地聚物密度影响不大,但会增大其吸水率。随着棉秆掺量的增加,C-FAG的抗折强度与抗压强度之比(折压比)呈现先增后减的趋势。掺入棉秆能够减少地聚物的表面孔隙,改变地聚物的破坏形式。用碱液处理棉秆和让地聚物在室温((20±2)℃)下先养护≥24 h再高温(75℃)养护,可以增大棉秆和地聚物的粘结强度。更多还原

【Abstract】 To clarify the role of cotton straw in geopolymers,eight groups of cotton fly ash based geopolymer( C-FAG) samples were tested for physical and mechanical properties,and scanning electron microscopy( SEM) was used to observe the C-FAG section. Curing conditions,cotton stalk treatment methods and cotton stalks content were analyzed to define the influence of density,water absorption,the surface condition,the failure mode of compression,the section characteristics,compressive and flexural strength of geopolymer. The results show that cotton stalk has little effect on the density of the geopolymer,but it will increase the water absorption of geopolymer. With the increase of cotton stalk content,the ratio of flexural strength to compressive strength( bend-press ratio) of C-FAG show a trend of increasing first and then decreasing. Cotton stalk can reduce the surface porosity of the geopolymer and change the destruction form of geopolymer. After cotton stalk is treated by alkali solution and geopolymers is cured at room temperature(( 20 ± 2) ℃) for ≥24 h before high temperature( 75 ℃) curing,the binding strength of cotton stalk and geopolymer gels can increase.更多还原