摘要
为了解决现有加固材料加固施工周期长、与旧混凝土结构黏结差等问题,利用改性磷酸镁水泥(magnesium phosphate cement,MPC)作为胶凝材料,制备3种不同骨料类别的MPC混凝土,研究其与普通混凝土力学性能的差异以及不同骨料对其力学性能的影响.以普通混凝土作为对照,制作4组棱柱体试件进行单轴抗压试验.结果表明:MPC混凝土的峰值应变明显高于普通混凝土,轻骨料的加入使其峰值应变进一步升高;其弹性模量明显低于普通混凝土,轻骨料使其弹性模量进一步降低;4组混凝土试件弹性阶段泊松比均为0.2左右,但MPC混凝土峰值时的泊松比明显高于普通混凝土,进入塑性阶段后MPC混凝土内部裂隙发展比例更高,最终破坏现象更加突然,试件破坏后更加松散.因此,MPC混凝土与普通混凝土相比脆性更强.
To solve the problems of long construction period of existing reinforcement materials and poor adhesion with old concrete structures,three kinds of magnesium phosphate cement(MPC)concrete were prepared by modified magnesium phosphate cement,the difference of mechanical properties between MPC and the ordinary portland cement(OPC)concrete and the influence of different aggregates were studied.Contrasting with OPC concrete,MPC concrete prismatic specimens were prepared for uniaxial compression test.The experimental findings show that the peak strain of MPC concrete is obviously higher than that of OPC concrete,and with adding lightweight aggregate,the peak strain of MPC concrete increases further.Its modulus of elasticity is obviously lower than that of OPC concrete,besides,the modulus of elasticity reduces further due to lightweight aggregate added.The Poisson ratio is about 0.2 at the elastic phase,but the Poisson ratio of MPC concrete is higher than that of OPC concrete at high stress.After the inelastic phase,there are more internal cracks,and the final failure phenomenon is more abrupt and looser after failure.MPC concrete shows stronger brittleness than OPC concrete.
作者
谢剑
李明
白伟亮
XIE Jian;LI Ming;BAI Weiliang(School of Civil Engineering,Tianjin University,Tianjin 300072,China;Key Laboratory of Coast Civil Structure Safety,Ministry of Education,Tianjin University,Tianjin 300072,China;China Electronics Engineering Design Institute Co.,Ltd.,Beijing 100142,China;C+E Center for Engineering Research Test and Appraisal Co.,Lud.,Bejjing 100142,China)
出处
《北京工业大学学报》
CAS
CSCD
北大核心
2020年第8期948-955,共8页
Journal of Beijing University of Technology
基金
国家自然科学基金资助项目(51978459)。
