摘要
针对大跨度拱桥不规则截面双拱肋的气动特性问题,以国内某座大跨度拱桥跨中不规则五边形截面双钢拱肋为工程背景开展研究。首先,通过刚性节段模型测压试验,测试该拱肋在8个不同间距比和11个不同风攻角下的气动力系数和斯托罗哈数,并与单拱肋的结果进行对比分析;然后,通过数值计算方法,研究风攻角α=0°条件下间距对气动特性的影响机理。结果表明:双拱肋的气动力系数存在明显的临界间距效应,当α=-5°时,临界间距比(L/B)_(cr)=2.0~2.5,其他风攻角下,(L/B)_(cr)=2.5~3.0;上游拱肋的气动力系数在L/B<(L/B)_(cr)时表现为明显的减小效应,而在L/B>(L/B)_(cr)时干扰效应不明显;下游拱肋的阻力和扭矩系数绝对值均表现为显著的减小效应,升力系数的干扰效应与风攻角密切相关;不同间距比下双拱肋的斯托罗哈数在不同程度上均小于单拱肋的斯托罗哈数。
Concerning the aerodynamic characteristics of twin arch ribs with irregular cross-sections in longspan arch bridges,this study is conducted using a domestic long-span arch bridge with twin steel arch ribs featuring an irregular pentagonal cross-sections at mid-span as the engineering context.First,aerodynamic force coefficients and Strouhal numbers are measured through pressure tests on rigid sectional models under 8 distinct spacing ratios(L/B)and 11 wind attack angles(α),and a comparative analysis is conducted with results from single arch ribs.Subsequently,numerical simulations are employed to investigate the influence mechanisms of spacing on aerodynamic characteristics atα=0°.The results indicate that the aerodynamic force coefficients of twin arch ribs exhibited a distinct critical spacing effect.Whenα=-5°,the critical spacing ratios(L/B)_(cr) ranged from 2.0 to 2.5,while under other wind attack angles,(L/B)_(cr) extends from 2.5 to 3.0.For the upstream arch ribs,the aerodynamic force coefficients show a significant reduction effect when L/B<(L/B)_(cr),whereas interference effects became negligible when L/B>(L/B)_(cr).The absolute values of drag and torque coefficients for the downstream arch ribs display a pronounced reduction effects,while the interference effects on lift coefficients are highly sensitive to wind attack angles.The Strouhal numbers of twin arch ribs at varying spacing ratios are consistently lower than those of single arch ribs to varying extents.
作者
刘小兵
张德旺
丰斌
王欣
杨群
LIU Xiaobing;ZHANG Dewang;FENG Bin;WANG Xin;YANG Qun(State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures,Shijiazhuang Tiedao University Shijiazhuang,050043,China;Innovation Center for Wind Engineering and Wind Energy Technology of Hebei Province Shijiazhuang,050043,China;School of Civil Engineering,Shijiazhuang Tiedao University Shijiazhuang,050043,China)
出处
《振动.测试与诊断》
北大核心
2025年第4期658-665,839,840,共10页
Journal of Vibration,Measurement & Diagnosis
基金
国家自然科学基金资助项目(52008273,52078313)
河北省自然科学基金资助项目(E2020210083)
河北省自然科学基金创新研究群体资助项目(E2022210078)
中央引导地方科技发展资金资助项目(236Z5407G,236Z5410G)。
关键词
不规则五边形双钢拱肋
气动力系数
斯托罗哈数
风洞试验
气动干扰
irregular pentagonal twin steel arch ribs
aerodynamic force coefficients
Strouhal numbers
wind tunnel test
aerodynamic interference
作者简介
第一作者:刘小兵,男,1982年3月生,博士、教授。主要研究方向为桥梁与结构的风荷载、风致振动与控制。曾发表《不同高宽比并列双幅箱梁气动升力的干扰效应》(《振动、测试与诊断》2023年第43卷第1期)等论文。E-mail:x_b_liu@126.com;通信作者:杨群,女,1981年11月生,博士、讲师。主要研究方向为桥梁与结构风工程。E-mail:quny123@126.com。
