摘要
为探究超轻质水泥基复合材料(ultra lightweight cement composite,ULCC)的基本力学性能及应力-应变曲线本构关系.以粉煤灰空心微珠为唯一轻质微集料,以水泥和硅灰为胶凝材料,以高效减水剂和减缩剂为外加剂,配制了钢纤维体积掺量为1%,表观密度介于1 250~1 550 kg/m3,轴心抗压强度介于47.9~70.0 MPa的4种不同密度等级的ULCC.对其分别进行单轴抗压和单轴抗拉试验,分别研究了ULCC的轴心抗压和轴心抗拉力学性能,测得了ULCC材料轴心抗压强度、轴心抗拉强度、弹性模量、泊松比及单轴抗压和单轴抗拉应力-应变曲线.结果表明:ULCC的抗压强度、抗拉强度和弹性模量均随密度的增加而增加; ULCC的轴心抗压强度和弹性模量与密度呈较强线性相关性.轴心抗拉试验结果表明ULCC抗拉应力-应变曲线关系呈现明显的峰后平台段,ULCC材料具有良好的拉伸变形能力.根据试验测得的ULCC单轴抗压和单轴抗拉应力-应变全曲线,建立了ULCC单轴抗压和单轴抗拉的分段式应力-应变本构方程.研究成果可为ULCC结构的设计和非线性有限元计算提供理论依据.
In order to investigate the mechanical properties and constitutive relation of stress-strain for ULCC （ ultra lightweight cement composite ）, four types of ULCC with different densities ranging from 1 250 kg/ms to 1 550 kg/ms and the corresponding compressive strengths ranging from 47.9 MPa to 70.0 MPa were developed in this paper. These ULCC consisted of microlightweight aggregates （cenospheres）, cementing materials （cement and silica fume） , concrete admixtre （shrinkage reducing admixtre and superplasticizer） and steel fiber with volume freaction of 1%. An experimental campaign including uniaxial compressive strength tests and uniaxial tensile strength tests was undertaken to investigate the uniaxial compressive and tensile mechanical properties, and the compressive strength, tensile strength, elastic modulus, poisson ratio, uniaxial compression stress-strain curves and uniaxial tension stress-strain curves were, obtained. The results show that compressive strength, tensile strength, and elastic modulus all increased with the increasing of densities. The compressive strength and elastic modulus of ULCC were linearly related to densities. The segmented constitutive equations of ULCC under uniaxial compression and uniaxial tension were proposed based on the uniaxial compression stress-strain curves and uniaxial tension stress-strain curves obtained from the tests. The research results can provide theoretical basis for the design and nonlinear finite element calculation of ULCC structure.
作者
杲晓龙
王俊颜
GAO Xiaolong, WANG Junyan(Key Lab of Advanced Civil Engineering Materials （Tongji University）, Ministry of Education, Shanghai 201804, China)
出处
《哈尔滨工业大学学报》
EI
CAS
CSCD
北大核心
2018年第12期67-73,共7页
Journal of Harbin Institute of Technology
基金
国家自然科学基金青年基金(51609172)
上海市浦江人才计划(16PJ1409900)
上海市科委项目(17DZ1204200)
关键词
超轻质水泥基复合材料
应力-应变曲线
本构关系
抗压强度
抗拉强度
ultra lightweight cement composite
stress-strain curve
constitutive laws
compressive strength
tensile strength
