高水灰比轻集料混凝土的制备与基本性能  

Preparation and Properties of Lightweight Aggregate Concrete by Using Higher Water-Cement Ratio

作　　者：陈伟[1] 钱觉时[1] 刘军[1] 汪宏涛[2] 贾兴文[1] 

机构地区：[1]重庆大学材料科学与工程学院,重庆400045 [2]后勤工程学院化学与材料工程系,重庆400016

出　　处：《建筑材料学报》2014年第2期298-302,335,共6页Journal of Building Materials

基　　金："十二五"国家科技支撑计划项目(2011BAE14B06-03)

摘　　要：提出了高水灰比配制轻集料混凝土的技术途径.采用2种密度陶粒和陶砂配制轻集料混凝土,研究了水灰比对其坍落度损失、吸水性能、轻集料分层度以及抗压强度的影响.结果表明:提高水灰比能明显降低轻集料混凝土的坍落度损失与轻集料分层度;当水灰比0.75(质量比)时,采用表观密度为738kg/m3的陶粒及其破碎后制备的陶砂可配制干密度低于900kg/m3,28d抗压强度约为14MPa的轻集料混凝土;高水灰比轻集料混凝土的收缩和吸水性能可控制在相对较低的范围内;轻集料越轻,水灰比增加幅度可越大,不仅可以显著降低轻集料混凝土的坍落度损失和轻集料上浮,还能在其大幅度降低密度的情况下保持较高抗压强度.A way of producing lightweight aggregate concrete by using higher mw/mc was proposed. Two types of lightweight aggregates were used to prepare lightweight concrete. Variations of the slump loss, segregation of lightweight aggregates, and compressive strength of the concrete with different mw/mc were investigated. It is shown, when mw/mc is 0. 75 , a lightweight aggregate concrete with bulk densi- ty of less than 900 kg/ma and 28 d compressive strength of 14 MPa is obtained by using a coarse ex- panded shale with apparent density of 738 kg/m3 and resulting fine aggregate by crushing. The shrink- age and water absorption of lightweight aggregate concrete, prepared by using higher mw/rnc, are with- in an acceptable range. It is suggested that the lighter the lightweight aggregate, the higher the rnw/rnc, the less the segregation of the aggregate and slump loss of the concrete, and the higher the retained com- pressive strength.

关 键 词：水灰比 轻集料 坍落度 分层 抗压强度 

分 类 号：TU528.2[建筑科学—建筑技术科学]