水泥基材料瞬时高温作用下的爆裂与力学性能  

Spalling and Physical Properties of Cement-Based Material Under Instantaneous High Temperature

作　　者：马保国[1] 王耀城[1] 穆松[1] 金磊[1] 

机构地区：[1]武汉理工大学硅酸盐材料工程教育部重点实验室,武汉430070

出　　处：《土木建筑与环境工程》2013年第4期109-113,共5页Journal of Civil,Architectural & Environment Engineering

基　　金：国家“863”资助项目(2005AA332010)

摘　　要：水泥基材料经瞬时高温作用后,随受火温度不同,表现出不同的爆裂与力学性能。研究了掺加不同矿物掺和料的水泥基材料在不同的瞬时高温作用后爆裂与力学性能的影响。结果表明:在100℃和300℃瞬时高温作用下,所有试样外观完整,未发生爆裂;600℃时,所有试件发生粉碎性爆裂。与室温下水泥基材料的物理力学性能相比,在经历瞬时100℃作用后,试样的抗压、抗折强度损失率分别达到15%和30%以上;经受300℃作用后,强度恢复至室温时强度水平;温度高于300℃时,随温度的升高,强度逐渐降低;当温度高于600℃时,强度急剧衰减。其中,复掺20%矿粉和10%硅灰的试样经历的低温(≤300℃)作用后,抗压、抗折强度均随温度的增加而提高。SEM分析表明,经600℃高温作用2h后,硬化水泥浆体C-S-H整体结构疏松,水化产物连续相被分割为非连续相。Cement-based material has different spalling and physical properties after exposing to different high temperatures.The spalling and physical properties of cement-based material with different additives after exposing to instantaneous high temperature were analyzed.The results show that： all samples have no spalling both at 100℃ and 300℃,but spalling completely at 600℃.The compressive strength and flexural strength of the cement-based material at 100℃ decrease by the rate of 15% and 30%,and the value at 300℃ is close to that at room temperature and decreases rapidly after exposing to 600℃.Both the compressive and the flexural strength of samples with 20% slag powder and 10% silica fume increase with the increase of the temperature when the temperature is below 300℃.SEM reflects that after exposing to 600℃ for 2 hours,C-S-H has changed into a looser structure,and the continuously cement paste is separated into segments.

关 键 词：水泥基材料 爆裂 瞬时高温 物理化学变化 微观结构 

分 类 号：TQ172[化学工程—水泥工业]