氧化钙膨胀剂减少碱激发矿渣混凝土自收缩的研究  

Study of reducing autogenous shrinkage of alkali-activated slag concrete with CaO expanding agent

作　　者：李军[1,2] 单继雄 胡艳民 侯永生 易善斌 LI Jun;SHAN Jixiong;HU Yanmin;HOU Yongsheng;YI Shanbin(Shijiazhuang Tiedao University,Shijiazhuang 050043,China;Hebei Provincial Technology Research Center of Road Structure and Engineering Material,Shijiazhuang 050091,China;Zhong Jiao Jian Ji Jiao Highway Investment Development Co.,Ltd.,Shijiazhuang 050000,China)

机构地区：[1]石家庄铁道大学,河北石家庄050043 [2]河北省道路结构与材料工程技术研究中心,河北石家庄050091 [3]中交建冀交高速公路投资发展有限公司,河北石家庄050000

出　　处：《混凝土》2023年第1期78-81,共4页Concrete

基　　金：河北省交通运输科技项目(JX-202013)。

摘　　要：碱矿渣混凝土具有早期强度高、耐久性好的优点,但又存在收缩大、易开裂的问题。以改性氧化钙作为膨胀剂,研究了碱矿渣混凝土的体积变形行为。结果显示:使用硬脂酸对氧化钙进行表面改性后,可以减轻后者对碱矿渣浆体凝结时间的影响。随膨胀剂掺量的增大,混凝土的28d抗压强度与自收缩均逐渐下降,当改性氧化钙掺量达到10%时混凝土发生明显的膨胀。对掺有改性氧化钙膨胀剂的减矿渣混凝土进行XRD、SEM、EDS测试,发现在混凝土中掺入膨胀剂后,水化产物中有氢氧化钙生成。Alkali slag concrete has the advantages of high early strength and good durability,but it has the problems of large shrinkage and easy cracking.The volume deformation behavior of alkali slag concrete with modified calcium oxide as expansion agent is studied.The results show that the influence of stearic acid on the setting time of alkali slag slurry can be reduced after surface modification of calcium oxide.The 28d compressive strength and autogenous shrinkage of concrete decrease gradually with the increase of the content of expansion agent,and the concrete expands obviously when the content of modified calcium oxide reaches 10%.XRD,SEM and EDS tests show that calcium hydroxide was formed in hydration products after adding expansion agent into concrete.

关 键 词：碱矿渣 自收缩 氧化钙 表面改性 

分 类 号：TU528.042.2[建筑科学—建筑技术科学]