复掺磷渣粉与石灰石粉完全替代粉煤灰对外掺MgO碾压混凝土性能的影响  

Effect on Performance of Mg O-admixed Concrete Mixed with Fly Ash Completely Replaced by Phosphorus Slag Powder and Limestone Powder

作　　者：林喜华 陈昌礼[2] 陈荣妃[2] 赵振华[2] 刘小萤[2] 叶鸿宏 LIN Xi-hua;CHEN Chang-li;CHEN Rong-fei;ZHAO Zhen-hua;LIU Xiao-ying;YE Hong-hong(China West Construction Guizhou CO.,Ltd.,Guiyang 550008,China;School of Materials and Architectural Engineering,Guizhou Normal University,Guiyang 550025,China)

机构地区：[1]中建西部建设贵州有限公司,贵州贵阳550008 [2]贵州师范大学材料与建筑工程学院,贵州贵阳550025

出　　处：《水电能源科学》2021年第10期148-151,共4页Water Resources and Power

基　　金：国家自然科学基金项目(51869005)。

摘　　要：针对部分水利水电工程很难采购到粉煤灰或粉煤灰落地价格过高的问题,以复掺磷渣粉与石灰石粉完全取代粉煤灰配制的外掺氧化镁(MgO)碾压混凝土为例,采用力学试验、变形观测、压汞测试、扫描电镜观察等手段,研究复掺磷渣粉与石灰石粉对外掺MgO碾压混凝土的力学性能、自生体积变形性能、微观性能的影响。结果表明,与单纯使用粉煤灰作为掺合料配制的外掺MgO碾压混凝土相比,采用复掺磷渣粉与石灰石粉完全替代粉煤灰配制的外掺MgO碾压混凝土的工作性、抗渗性和抗冻性无明显变化,对自生体积膨胀变形影响不大,但无害孔减少,平均孔径和孔隙率总体增大;随着石灰石粉掺量增大或磷渣粉掺量减少,外掺MgO碾压混凝土的抗压强度、劈拉强度、极限拉伸值下降;在石灰石粉掺量超过20%后,龄期90 d的外掺MgO碾压混凝土的抗压强度低于常用的坝体混凝土抗压强度的最低值15 MPa。In view of the fact that it is difficult to purchase fly ash or the high price of fly ash for some water conservancy and hydropower projects,this article takes the mixed phosphorous slag powder and limestone powder to completely replace the fly ash to make roller compacted concrete(RCC)admixed MgO additive as the research object.This paper studies the impact of complex phosphorus slag powder and limestone powder on the mechanical properties,self-generated volume deformation properties and microscopic properties of RCC admixed MgO by means of mechanical experiment,deformation observation,mercury injection test,scanning electron microscope observation.The results show that there is no obvious difference to use complex phosphorous slag powder and limestone powder to replace completely the fly ash to make RCC admixed MgO compared with RCC admixed MgO only added fly ash in workability,impermeability and frost resistance.And it has little impact on self-generated volume expansion deformation,but harmless hole is reduced,the average pore diameter and porosity increased overall.With the increase of limestone powder content or the decrease of phosphorus slag powder content,the compressive strength,splitting tensile strength and ultimate tensile value of RCC admixed MgO decrease.After the limestone powder content exceeds 20%,the compressive strength of 90 d RCC admixed MgO is lower than the minimum value of 15 MPa of commonly used dam concrete.

关 键 词：磷渣粉 石灰石粉 自生体积变形 外掺MgO碾压混凝土 

分 类 号：TV32[水利工程—水工结构工程]