摘要
为认识再生微粉在混凝土梁中的抗剪切力学性能,运用室内小比例尺试验,制作了不同再生微粉含量的混凝土梁抗剪切试验模型,设计了加载试验方案,研究其受到破坏时的裂缝发展、荷载-跨中挠度和抗剪切承载力变化特征。结果表明:再生微粉混凝土梁裂缝发展经历了初裂、裂缝扩展及贯通和试件破坏3个阶段,梁的荷载-跨中挠度变化大致可以分为弹性阶段、非线性阶段和破坏阶段;参考我国规范与美国规范得到的再生微粉混凝土梁斜截面抗剪切承载力均比实测值小,抗剪切承载力实测值与我国规范计算值之比(V_(实测)/V_(u))的变化范围为1.78~2.17,抗剪切承载力实测值与美国规范计算值之比(V_(实测)/V_(n))的变化范围为1.89~2.64,且V_(实测)/V_(u)与V_(实测)/V_(n)均随着再生微粉含量的增加而不断减小。
In order to understand the shear mechanical properties of recycled fine powder in concrete beams,laboratory small scale tests were used to make shear test models of concrete beams with different content of recycled fine powder.A loading test scheme was designed to study the crack development,load-span deflection and shear bearing capacity of the beams when they were damaged.The results show that the crack development of concrete beams with recycled fine powder content goes through three stages:initial crack,crack expansion and penetration,and specimen failure.The load-mid-span deflection of beams can be roughly divided into elastic stage,nonlinear stage,and failure stage.The shear bearing capacity of recycled fine powder concrete beams on oblique sections obtained by reference to the Chinese code and the American code is smaller than the measured value.The ratio of the measured value of shear bearing capacity to the calculated value of the Chinese code V_(measured)/V_(u)varies from 1.78 to 2.17,and the ratio of the measured value of shear bearing capacity to the calculated value of the American code V_(measured)/V_(n)varies from 1.89 to 2.64.Both V_(measured)/V_(u)and V_(measured)/V_(n)decreased with the increase of the content of recycled fine powder.
作者
黄炎辉
HUANG Yanhui(Fujian Zhongjian Zhongxin Technology Testing Co.,Ltd.,Fuzhou 350300,China)
出处
《上海建材》
2023年第6期18-21,共4页
Shanghai Building Materials
关键词
再生微粉
混凝土梁
力学性能
抗剪切强度
室内试验
recycled fine powder
concrete beam
mechanical property
shear strength
Laboratory test
