洞口形状对腹板开洞钢-混凝土组合梁的受力性能影响分析  

Analysis of influence of opening shape on mechanical performance of steel-concrete composite beams with web openings

作　　者：蒋伟 廖文远 刘德稳 陈静 谢鑫 JIANG Wei;LIAO Wenyuan;LIU Dewen;CHEN Jing;XIE Xin(College of Civil Engineering,Southwest Forestry University,Kunming 655024,Yunnan,China)

机构地区：[1]西南林业大学土木工程学院,云南昆明655024

出　　处：《建筑科学与工程学报》2023年第3期61-69,共9页Journal of Architecture and Civil Engineering

基　　金：国家自然科学基金青年科学基金项目(51808467);云南省科技厅青年项目(2017FD107)。

摘　　要：通过研究洞口形状对腹板开洞钢-混凝土组合梁受力的影响,选择合适的洞口形状以降低开洞造成的不利影响;在已有试验基础上,利用ANSYS对洞口设置在弯剪区段且洞口形状不同的组合梁进行力学性能分析,研究了洞口形状对承载力、变形能力以及内力重分布和传力机制的影响。结果表明:钢-混凝土组合梁腹板开洞会导致刚度、极限承载力下降;非正方形洞口组合梁因洞口形状不同,极限变形有不同程度增强;洞口形状会影响洞口处混凝土、钢梁承担的剪力比例,混凝土占总剪力的46%~59%,而钢梁占总剪力的41%~54%;极限变形与洞口处塑性铰的面积大小有关;栓钉会对周围的混凝土产生一定预压力,对混凝土应力重分布有影响,洞口处混凝土的剪力有明显的剪力差,洞口下方钢梁所承受的剪力大于洞口上方钢梁;洞口形状会影响组合梁内部传力机制,长方形、正方形洞口试件在洞口区域以次弯矩传递力,非长方形、正方形洞口试件在洞口区域以主弯矩传递力;在结构设计时应该考虑洞口位置的偏心、主应力方向与洞口边缘的夹角。By studying the influence of opening shape on the stress of steel-concrete composite beams with web openings,selecting an appropriate opening shape to reduce the adverse effects caused by opening.Based on existing experiments,ANSYS was used to analyze the mechanical performance of composite beams with different shapes of openings in the bending shear section.The influence of opening shape on bearing capacity,deformation capacity,internal force redistribution,and force transmission mechanism was studied.The results show that web opening of steel concrete composite beams can lead to a decrease in stiffness and ultimate bearing capacity.The ultimate deformation of composite beams with non square openings is enhanced to varying degrees due to different shapes of openings.Shapes of openings will affect the proportion of shear force borne by concrete and steel beams at the opening.Concrete accounts for 46%-59%of the total shear force,while steel beams account for 41%-54%of the total shear force.The ultimate deformation is related to the area of the plastic hinge at the opening.Studs will exert a certain pre-pressure on the surrounding concrete and have an impact on the redistribution of stress in the concrete.There is a significant difference in shear force in the concrete at the entrance,and the shear force borne by the steel beam below the entrance is greater than that of the steel beam above the entrance.The shape of the opening will affect the internal force transfer mechanism of the composite beam.The rectangular and square opening specimens transmit force through secondary bending moment in the opening area,while the non rectangular and square opening specimens transmit force through primary bending moment in the opening area.In structural design,consideration should be given to the eccentricity of the opening position and the angle between the direction of the main stress and the edge of the opening.

关 键 词：组合梁 腹板开洞 洞口形状 受力性能 

分 类 号：TU398.9[建筑科学—结构工程]