引气剂与粉煤灰对大流动性轻集料混凝土性能的影响  

Effect of air-entrained admixture and fly ash on property of large flowing lightweight concrete

作　　者：郑秀华[1] 张宝生[1] 袁杰[1] 徐弛[1] 郭永智[1] 

机构地区：[1]哈尔滨工业大学材料学院,黑龙江哈尔滨150001

出　　处：《混凝土》2005年第4期88-92,共5页Concrete

基　　金：哈尔滨工业大学校优秀青年基金(01502976)

摘　　要：为改善大流动性轻集料混凝土的匀质性,采用粉煤灰和引气剂复合技术,配制出高性能轻集料混凝土。结果表明:掺入优质粉煤灰并适量引气(含气量为3%-5%),可明显提高轻集料混凝土的匀质性,减少离析和泌水,获得匀质的混凝土拌合料。当水胶比为0.31时,掺入10%-30%的粉煤灰及适量引气剂,28d抗压强度不降低,56d抗压强度可提高10%左右,抗冻性和抗渗性明显改善;当水胶比为0.40时,随粉煤灰掺量的增加,轻集料混凝土的抗压强度明显降低。同时,探讨了粉煤灰和引气剂对轻集料混凝土性能改善的机理。To improve the homogeneity of large flowing lightweight concrete, fly ash and air-entrained admixture are incorporated together into concrete and high performance lightweight concrete was prepared. The test results indicate fly ash and entrained air can improve the homogeneity of lightweight concrete and reduce segregation and bleeding of concrete mixture. When the water-binder ratio is 0. 31, incorporated with 10 to 30 percent fly ash and proper air, the compressive strength of lightweight concrete at 28 days is not decreased, but also the compressive strength at 56 days increased about 10 percent. The frost resistance and impermeability of concrete can improve apparently. When the water-binder ratio is 0.40, the compressive strength of concrete decreased with increase of fly ash dosage. The improved mechanism of fly ash and air-entrained admixture is studied.

关 键 词：轻集料混凝土 引气剂 粉煤灰 匀质性 强度 耐久性 

分 类 号：TU528.2[建筑科学—建筑技术科学]