摘要
为明确72 h龄期内钢筋混凝土梁力学性能的影响,采用液压伺服助动器对10根超早龄期钢筋混凝土梁进行四点弯曲试验,探讨72 h龄期内的破坏形态与力学性能,进而确定早龄期混凝土本构关系和塑性损伤参数,利用有限元进行参数分析。结果表明:超早龄期混凝土梁的破坏形态受龄期影响较为显著,随着龄期增长,其破坏形态由最初的弯剪段斜压破坏向纯弯段的弯曲破坏转变;龄期对超早龄期钢筋混凝土梁的开裂弯矩和截面弯曲刚度有较大影响,但对极限弯矩影响相对较小。考虑到超早龄期混凝土梁四点弯曲主要发生弯剪段破坏,将现行规范式的计算值与有限元的计算结果进行对比,二者比值为1.08~1.58。
In order to clarify the influence of mechanical properties of reinforced concrete beams at 72 h age,hydraulic servo actuators were used to conduct four-point bending tests on 10 ultra-early-age reinforced concrete beams.The failure mode and mechanical properties at 72 h age were discussed,and the constitutive relationship and plastic damage parameters of early-age concrete were determined.The finite element method was used for parameter analysis.The results show that the failure mode of super early age concrete beams is significantly affected by the curing age.With the increase of age,the failure mode changes from the initial diagonal compression failure of the bending shear section to the bending failure of the pure bending section.Age has a great influence on cracking moment and section bending stiffness of ultra-early-age reinforced concrete beams,but has a relatively small influence on ultimate bending moment.Considering that the four points of the super early age concrete beam mainly occur bending shear failure,the calculated value of the current code formula is compared with the calculated value of the finite element,and the ratio is roughly in the range of 1.08 to 1.58.
作者
庄金平
任凯
杨尊煌
郑居焕
ZHUANG Jinping;REN Kai;YANG Zunhuang;ZHENG Juhuan(Fujian Provincial Key Laboratory of Advanced Technology and Informatization in Civil Engineering,Fuzhou 350118,China;School of Civil Engineering,Fujian University of Technology,Fuzhou 350118,China)
出处
《混凝土》
CAS
北大核心
2023年第12期29-34,共6页
Concrete
基金
国家自然科学基金(51678152)
福建省自然科学基金面上项目(2021J011063)
福建省高校新世纪人才项目(GY-Z17069)。
关键词
超早龄期
弯剪区段
有限元
参数分析
抗剪计算
ultra-early age
bending shear section
finite element
parameter analysis
shear performance
