预应力薄壁圆钢管约束混凝土短柱轴压性能初探  

Study on Axial Compression Performance of Prestressed Thin-walled Circular Steel Tubular Confined Concrete Short Column

作　　者：刘德贵[1] 张华 李亮 邱寒月 Liu Degui;Zhang Hua;Li Liang;Qiu Hanyue(School of Civil Engineering and Architecture,Southwest University of Science and Technology,Mianyang 621010,China)

机构地区：[1]西南科技大学土木工程与建筑学院,绵阳621010

出　　处：《特种结构》2024年第4期27-35,共9页Special Structures

基　　金：四川省科技厅应用基础研究项目(2019YJ0437)。

摘　　要：为提高薄壁钢管混凝土柱轴心受压性能,提出了预应力薄壁圆钢管约束混凝土柱,即采用对拉螺栓对薄壁圆钢管施加环向预应力,形成对内部混凝土初始约束围压,以提高内部混凝土的轴心抗压强度及承载力性能。为探究其轴向受压性能提升效果,进行了预应力薄壁圆钢管约束混凝土短柱轴心受压试验;并采用ABAQUS有限元计算软件建立了相应的非线性有限元数值模型,基于试验所获得荷载-位移数据,验证了模型的可靠性。在合理可靠试验模型的基础上,进行了不同预应力度(k=0、0.1、0.2、0.3、0.4和0.5)和不同钢管厚度(t=1.5mm、2.0mm、2.5mm和3.0mm)情况下的轴心受压性能影响分析。结果表明:采用对拉螺栓对薄壁圆钢管混凝土柱施加环向预应力,可有效提高其轴心抗压强度、刚度和延性;在合适预应力范围内,预应力度(k=0~0.4)越大,预应力薄壁钢约束混凝土短柱轴心受压性能提升越明显;但较大的预应力度(k=0.5)会让构件在达到峰值荷载后,其承载力降低较为明显,从而使构件延性降低;当预应力度k不变,构件的轴心受压性能随钢管厚度t的增大而增大。To increase the axial compression performance of thin-walled concrete-filled steel tubular columns,the prestressed thin-walled circular steel tubular confined concrete column was presented,in which the tension bolts were used to apply circumferential prestressed force for thin-walled circular steel tube to form initial confining pressure on the internal concrete,and then the axial compressive strength and bearing capacity performance of internal concrete were improved.To investigate the improvement effect of the axial compression performance,the short column axial compression test was first conducted,and then a nonlinear finite element model was established with Abaqus software.The reliability of the model was verified based on the load displacement data obtained from the experiment.Based on the validated model,the parameter analysis was carried out for the prestressed thin-walled circular steel tubular confined concrete short column with different prestressed degrees(k=0,0.1,0.2,0.3,0.4 and 0.5)and different steel tube thicknesses(t=1.5mm,2.0mm,2.5mm and 3.0mm).The results show that applying circumferential prestressed force to thin-walled circular steel tube concrete columns using tension bolts can effectively improve their axial compressive strength,stiffness,and ductility.Within the appropriate range of prestressed force(k=0~0.4),the improvement in the axial compression performance of prestressed thin-walled steel confined concrete short columns increases with the prestressed de-gree increase.A larger prestressed degree(k=0.5)will cause to significantly decrease of structural element bearing capacity after reaching its peak load,thereby reducing the ductility of the structural element.When the prestressed degree k remains constant,the axial compression performance of the structural element increases with the steel pipe thickness increase.

关 键 词：预应力 薄壁圆钢管混凝土短柱 有限元 轴心受压性能 

分 类 号：TU378.3[建筑科学—结构工程]