内掺硅烷乳液憎水剂对混凝土性能的影响

通过强度测试、水化热实验、热重分析、毛细吸水实验以及压汞实验研究了内掺硅烷乳液憎水剂对混凝土强度以及毛细吸水性能的影响规律及其机理.结果表明:高掺量硅烷乳液一定程度上抑制水泥水化,从而导致混凝土早龄期抗压强度和劈裂抗拉强度下降以及28 d养护后水泥净浆试块中毛细孔的体积增大.毛细吸水实验表明:28 d龄期混凝土毛细吸水...

Influence of Silane Emulsion Hydrophobic Agent on Concrete Properties

Influence of silane emulsion hydrophobic agent as an additive on the strength and capillary water absorption behavior of concrete was investigated through strength test,hydration heat test,thermogravimetric analysis,capillary water absorption and mercury intrusion test.The results show that silane emulsion reduces the early-age compressive strength and splitting strength of concrete,which is mainly attributed to the retardation effect of silane emulsion on the early cement hydration.The capillary pore volume in 28-d harden cement paste is increased by adding silane emulsion because of the depressed cement hydration.However,the initial water absorption rate,the secondary water absorption rate and the total amount of water absorption of the 28-d concrete during capillary water absorption process are greatly reduced by silane agent.This is since silane emulsion reacts with cement hydration products to form an alkyl hydrophobic layer on the pore wall of the capillary pores,which changes the surface property of the wall from hydrophilic to hydrophobic,thus significantly reducing the rate and the amount of water absorption of concrete.Silane agent has a more profound influence on the concrete properties with a higher water-cement ratio due to the lager capillary pore volume.