摘要
为改善海水海砂混凝土(seawater sea sand concrete,SSC)脆性大的问题,以玻璃纤维(glass fiber,GF)和聚乙烯醇(poly⁃vinyl alcohol,PVA)纤维体积掺量为变量,制备相应试件并进行立方体抗压强度、劈裂抗拉强度、轴心抗压强度和弹性模量试验,结合扫描电子显微镜(scanning electron microscope,SEM)扫描和能谱仪(energy dispersive spectroscopy,EDS)点扫分析纤维增强海水海砂混凝土的微观结构,并基于灰色系统理论建立相应模型。结果表明,纤维能够有效减少裂缝的产生,使试件呈现延性破坏。总体而言,混掺纤维对SSC力学性能的提升优于单掺纤维,混掺比为2∶1时,抗压强度和劈裂抗拉强度分别提升了24.2%和38.8%,混掺比为1∶1时,轴心抗压强度和静弹性模量分别提升了34.5%和15.5%。通过SEM和EDS观测到纤维的掺入能够使基体更加密实,SSC主要劣势是腐蚀离子产生的盐类结晶和膨胀性物质削弱骨料与砂浆之间的粘结致使界面过渡区(interfacial transition zone,ITZ)存在缺陷。建立的NSGM(1,3)模型精度较高,精度达到Ⅱ级且符合长期预测,可为研究纤维增强海水海砂混凝土的强度发展提供有利依据。
As a countermeasure to the problem of brittleness of seawater sea sand concrete(SSC),volumetric admixture of glass fiber(GF)and polyvinyl alcohol(PVA)fiber was used as variable,the corresponding specimens were prepared,and the cube com⁃pressive strength,splitting tensile strength,axial compressive strength,and elastic modulus were tested.The microstructure of fiber reinforced seawater sea sand concrete was analyzed by scanning electron microscope(SEM)scanning and energy dispersive spectros⁃copy(EDS)dot scanning,and a model was established based on the grey system theory.The research results show that the fiber can effectively reduce the formation of cracks,leading to a ductile failure of the specimen.In general,the mechanical properties of mixed fiber were improved better than that of single fiber,and the hybrid ratio 2∶1 brings a improvement of 24.2%and 38.8%for the compressive strength and splitting tensile strength,respectively.The hybrid ratio of 1∶1 increases the axial compressive strength and elastic modulus by 34.5%and 15.5%.It was observed by SEM and EDS that fiber incorporation could densify the matrix,while the main disadvantage of SSC was that the salt crystallization generated by corrosive ions and swelling substances weakened the bond between aggregate and mortar,resulting in defects of interfacial transition zone(ITZ).The established NSGM(1,3)model has a high accuracy,the accuracy reaches classⅡand conforms to the long-term prediction,which provides a favorable basis for the study of the strength elvolution of fiber reinforced seawater sea sand concrete.
作者
孙传武
王学志
辛明
贺晶晶
SUN Chuanwu;WANG Xuezhi;XIN Ming;HE Jingjing(School of Civil and Architectural Engineering,Liaoning University of Technology,Jinzhou,Liaoning 121001,China;Power China Northwest Engineering Corporation Limited,Xi’an 710065,China)
出处
《中国科技论文》
CAS
2024年第4期443-451,474,共10页
China Sciencepaper
基金
辽宁省教育厅高等学校基本科研项目(LJKMZ20220979)
陕西省自然科学基础研究计划项目(XBY-PTKJ-2022-12)。
关键词
海水海砂混凝土
玻璃纤维
聚乙烯醇纤维
微观结构
灰色预测模型
seawater sea sand concrete
glass fiber
polyvinyl alcohol fiber
microstructure
grey prediction model
