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为了给实际工程中并列双箱梁的风荷载取值提供参考,针对并列双扁平箱梁和并列双钝体箱梁,通过节段模型测压风洞试验方法,测试了11个不同风攻角(-10°～10°)下并列双箱梁在15个不同间距时[双箱梁的净间距与单箱梁宽度的比值(D/B)为0.025～6]的阻力系数,并与单箱梁的阻力系数进行对比.定义干扰因子为并列双箱梁的上游(或下游)箱梁的阻力系数与单箱梁阻力系数的比值,定量研究并列双箱梁的气动干扰效应对阻力系数的影响,给出阻力系数干扰因子随风攻角和间距变化的等值线.研究结果表明:气动干扰效应对上游箱梁阻力系数的影响较小,上游扁平箱梁和上游钝体箱梁的阻力系数干扰因子的变化范围分别为0.75～1.30和0.88～1.20;气动干扰效应对下游箱梁阻力系数的影响较大,且表现为减小效应,这种减小效应随着间距的变小愈发显著;与下游扁平箱梁相比,气动干扰效应对下游钝体箱梁阻力系数的减小程度更大,影响范围更广,下游钝体箱梁阻力系数干扰因子最小值为-0.3左右,即使当D/B=6时,减小效应仍不可忽略.“,”In order to provide a reference for wind load value of twin parallel box girders in the specific engineering,pressure-measured wind tunnel tests of sectional models of twin parallel flat box girders and twin parallel bluff box girders were conducted.Drag coefficients of twin box girders with 15 different spaces under 11 different wind attacking angles were measured and compared with that of single box girder.The wind attacking angle ranged from-10° to 10°.The ratio of net spacing of twin box girders to the width of single box girder (D/B) ranged from 0.025 to 6.The interference factor was defined as the ratio of drag coefficient of forward (or leeward) box girder to that of single box girder.Aerodynamic interference effect on drag coefficient of twin parallel box girders was researched quantitatively.The interference factor of the drag coefficient was influenced by the wind attacking angle and spacing,whilst the contours of the interference factor were shown for the first time.The results show that the influence of the aerodynamic interference effect on drag coefficient of forward box girder is slight.The interference factors of forward flat box girder and forward bluff box girder range from 0.75 to 1.30 and 0.88 to 1.20,respectively.The influence of the aerodynamic interference effect on drag coefficient of leeward box girder is obvious,showing as the reducing effect.Such reducing effect is more notable in small spacing.Compared with the leeward flat box girder,the reducing interference effect on leeward bluff box girder is more remarkable.The minimum interference factor of leeward bluff box girder is around-0.3.The reducing effect on leeward bluff box girder cannot be neglected even when D/B=6.