间断焊接包管加固圆钢管构件轴压极限承载力研究

Ultimate Bearing Capacity of Circular Steel Pipes Reinforced by Wrap Pipe with Discontinuous Welding Under Axial Compression

为研究间断焊接包管加固杆件的轴心受压性能,设计了13组试件进行单调加载静力试验。对试件极限承载力、破坏模式、荷载-位移曲线和截面应变发展规律进行分析,对比了负载加固与非负载加固对试件极限承载力的影响。结果表明:包管构件的破坏模式可分为整体失稳破坏和内管外伸段强度破坏;包管构件内外管协同工作、共同受力,内管和外管都在屈服后发生整体失稳破坏;负载加固与非负载加固试件的极限承载力基本一致,相差2.2%,非负载加固试件与未加固试件相比,极限承载力最大提高了479.9%。根据试验结果对包管构件的ABAQUS有限元模型进行修正,并用该模型分析了各主要影响因素对包管构件极限承载力的影响规律。提出了包管构件极限承载力经验计算公式,且公式计算结果与试验结果吻合较好。

To study the axial compression performance of the steel pipes reinforced by wrap pipe with discontinuous welding,13 groups of specimens were designed for monotonic loading static test.The ultimate bearing capacity,failure mode,load-displacement curve and section strain development law of the specimens were analyzed.The influence of reinforcement under load and non-load on the ultimate bearing capacity of the specimens was compared.The results show that the failure modes of the wrapped pipe specimens can be divided into overall instability failure and strength failure of the inner tube extension section.The inner and outer pipes of the wrapped pipe specimen work collaboratively and bear loads together,and the inner and outer pipes all reach the overall instability failure after yielding.The ultimate bearing capacity of reinforced specimens under load and non-load is basically the same,with a difference of 2.2%. The ultimate bearing capacity of reinforced specimens under non-load is 479.9% higher than thatof unreinforced specimens. According to the test results, the ABAQUS finite element model of the wrapped pipespecimens was modified, and the model was used to analyze the influence law of the main influencing factors on theultimate bearing capacity of the wrapped pipe specimen. An empirical formula for calculating the ultimate bearingcapacity of the wrapped pipe specimens was proposed, and the calculation results were in good agreement with theexperimental results.