摘要
碱激发混凝土是一种性能与水泥混凝土相似的新型环保建筑结构材料,加入钢纤维可以延缓混凝土开裂,改善混凝土构件的韧性与延性。通过钢纤维碱激发混凝土轴压强度、劈裂抗拉强度和三点弯曲断裂的材料性能试验;以及6根钢筋钢纤维碱激发混凝土梁构件的弯曲试验,研究了钢纤维对荷载-跨中挠度曲线、延性、破坏形态和跨中截面应变的变化规律。研究结果表明:钢纤维的加入对碱激发混凝土的轴压强度没有明显影响,但劈拉强度可提高32.5%~53.4%,断裂能大幅提高。钢纤维的加入使钢筋碱激发混凝土梁的抗弯承载力提高5.7%~18.2%,延性提高了16.4%~45.9%。钢纤维对低配筋率的适筋梁影响更明显。
Alkali-activated concrete is a new kind of environmentally friendly building structural material which similar properties to cement concrete,the addition of steel fiber can delay the cracking of concrete as well as improve the toughness and ductility of concrete members.The effect of steel fiber on the load-mid-span deflection curve,ductility,failure mode and strain in mid-span section of alkali-activated concrete are studied by the material performance tests such as axial compression,splitting tension and three-point bending,and the flexural bending tests of six reinforced steel fiber alkali-activated concrete beams.It is found that no obvious improvement is noticed in the axial compressive strength of alkali-activated concrete due to the addition of steel fibers.However,the splitting tensile strength can be increased by 32.5%~53.4%,and the fracture energy increased greatly.The addition of steel fiber also increases the flexural capacity of the steel bar-reinforced concrete beam by 5.7%to 18.2%,and the ductility increases by 16.4%to 45.9%.Steel fiber has more significant effect on the under-reinforced beams with low reinforcement ratio.
作者
王怀亮
黄永杰
朱建威
WANG Huailiang;HUANG Yongjie;ZHU Jianwei(College of Civil Engineering and Architecture,Guangxi University,Nanning 530004,China)
出处
《混凝土》
CAS
北大核心
2020年第12期155-159,共5页
Concrete
基金
国家自然科学基金资助项目(51768003,51868005)
广西自然科学基金资助项目(2017GXNSFAA198360)
广西大学人才基金资助项目(XGZ160701)
大连理工大学海岸和近海工程国家重点实验室开放基金项目(LP1618)。
关键词
钢纤维
碱激发混凝土
材料性能
弯曲性能
延性
steel fiber
alkali-activated concrete
material properties
flexural behavior
ductility
