摘要
为研究钢筋混凝土(RC)短柱在超低温条件下轴心受压承载力可靠度,运用JC法,对超低温环境下我国现行混凝土结构设计标准中的短柱设计可靠指标β进行计算分析,重点研究荷载效应比值、混凝土强度等级、钢筋强度等级以及钢筋直径等因素对超低温短柱承载力可靠指标的敏感性影响。研究结果表明:荷载效应比值对可靠指标β影响较大,最不利情况取值为0.1,较于取0.5、1.0、2.0时可靠指标β降低25.8%、33.4%、34.1%;随温度降低各试验组承载力可靠指标β均先稍微降低,-20℃时降至极小值,-20℃~-100℃间可靠指标曲线陡然上升且增幅稳定;当混凝土等级从C30提高至C50可靠指标β增幅达76%以上,钢筋等级的提高和直径的增大引起可靠指标增幅为2.9%~6.6%。
By using the basic principles of the JC method to compute and analyze the reliability indexβof the concrete short column design in the current concrete specifications of concrete structural design in my country,it is possible to research the reliable carrying strength of the reinforced concrete short column in the ultra-low temperature environment under centric axial compression degree.In particular,it focuses on the sensitivity of the load action ratio,strength levels of concrete,intensity level of reinforcing steel bar and diameter of rebar in the ultra-low temperature environment on the reliability of the short column carrying strength.The research results show that the reliability indexβwill be extraordinarily impacted by the load action ratio.The worst case value is 0.1,which reduces the reliability indexβby 25.8%,33.4%,and 34.1%compared with 0.5,1.0,and 2.0.;each test decreases with the temperature,The reliability indexβof the group carrying strength first decreases slightly,and drops to a minimum value at-20℃.The reliability index curve between-20℃and-100℃rises abruptly and the increase is stable;when the level of concrete is increased from C30 to C50,the increase of the reliability indexβreaches Above 76%,the increase in the grade and diameter of rebar increases the reliability index by 2.9%to 6.6%.
作者
刘威
李扬
LIU Wei;LI Yang(School of Civil Engineering and Environmental,Hubei Univ.of Tech.,Wuhan 430068,China)
出处
《湖北工业大学学报》
2022年第4期92-96,共5页
Journal of Hubei University of Technology
基金
国家自然科学基金(51508171)
湖北省自然科学基金(2020CFB860)
湖北省桥梁安全监控技术及装备工程技术研究中心开放基金(QLZX2014001)。
关键词
超低温
RC短柱
受压承载力
JC法
可靠指标
荷载效应比
ultra-low temperature
RC short column
compressive carrying strength
JC method
reliability index
load action ratio
