摘要
为了研究较大长细比带约束拉杆薄壁型钢管-竹胶板组合空芯长柱(SBCCB)的轴心抗压性能,采用4根试件进行轴压实验,考察SBCCB的破坏形态、特性、抗压承载力、变形情况;基于实验结果建立有限元模型,综合分析长细比、净截面尺寸、约束拉杆相对竖向间距比和排数对极限承载力的影响规律;通过非线性回归分析,建立了考虑约束拉杆相对竖向间距比、排数影响的轴心抗压承载力计算公式。结果表明:SBCCB的抗压破坏形态为柱端竹胶板压溃、局部开胶剥离破坏、压曲整体失稳破坏;随着长细比的增大,极限承载力降低,组合柱失稳破坏的趋势增大,发生失稳破坏的长细比限值在70附近;极限荷载不仅与净截面尺寸和长细比相关,而且受约束拉杆设计方式的影响较大;优化约束拉杆设置能有效延缓试件的开胶失效,改变破坏形态而提高极限承载力。
In order to study the axial compressive performance of thin-walled steel tube/bamboo-plywood composite hollow long column with binding bars(SBCCB) of large slenderness ratio, 4 specimens are used to perform the axial compression tests, the failure modes and characteristics of SBCCB are investigated. Based on the test results, finite element models are established, and the influences of slenderness ratio, net sectional size, and the relative spacing ratio and row number of binding bars on the ultimate bearing capacity are analyzed. The results indicate that the compressive failures of SBCCB are principally characterized by crush of bamboo plywood at the end of column, partial glue failure and compression buckling failure. The increase of slenderness ratio enlarges the risk of buckling failure. The ultimate bearing capacity is not only related to net sectional size and slenderness ratio, but also greatly affected due to binding bars. The optimization of binding bars can effectively suppress the glue failure and change the failure modes to improve ultimate bearing capacity. Based on the data from the axial compression test and finite element numerical simulation, as well as the code for design of timber structures, the calculating formulas which take the influences of relative spacing ratio and row number of binding bars into consideration for the axial compressive ultimate bearing capacity are established through nonlinear regression analysis, and they provide a reference for engineering applications of SBCCBs.
出处
《应用力学学报》
CAS
CSCD
北大核心
2018年第3期489-495,共7页
Chinese Journal of Applied Mechanics
基金
国家自然青年科学基金(51708476)
湖南省自然青年科学基金(2017JJ3302)
广东省自然科学基金(2017A030310579)
广东建设职业技术学院项目(ZD2017-01)
关键词
胶合竹板
薄壁型钢管
组合空芯柱
轴向抗压
承载力
bamboo plywood
thin-walled steel tube
composite hollow column
axial compression
bearing capacity
