【摘要】 为了研究超大型深水钢吊箱围堰在随机波浪力作用下的动力响应,以苏通大桥5#钢吊箱为工程背景,建立了对应的整体有限元模型.基于文氏谱以及线性谐波叠加法完成了波浪频谱与波浪时程的转换,进而得到了钢吊箱在频域与时域内的动力响应,并与特征波法和规范静力法进行了对比.结果表明,钢吊箱基频高,整体刚度较大;考虑附连水质量的影响,钢吊箱的自振频率急速下降,更接近波浪力谱峰值频率,增大了共振的可能性,动力分析时必须考虑附连水质量的影响;波浪荷载作用下,钢吊箱的动力效应普遍增大,但幅度增大较小.实际工程中,应在静力计算结果的基础上乘以1.15的放大系数,或者直接采用特征波法进行计算.更多还原

【Abstract】 In order to investigate the dynamic response of ultra-large deep-water steel suspension box cofferdam(SSBC) with the action of random wave force,a corresponding global finite element model was established with taking the No.5 steel suspension box of Sutong Yangtze river bridge as the engineering background.Meanwhile,the transformation between wave frequency-spectrum and wave time-history was completed based on both Wen’s wave spectrum and linear harmonic wave superposition method.The dynamic response of the steel suspension box in both time domain and frequency domain was obtained,and then compared with that attained by characteristic wave and standard static force methods.The results show that if the fundamental frequency of the steel suspension box is high,the global stiffness is larger.With considering the effect of the added water mass,the natural vibration frequency of the steel suspension box sharply decreases,and is closer to the peak frequency of wave force spectrum,which increases the possibility of resonance.Thus,the influence of the added water mass must be considered in dynamic analysis.With the action of wave load,the dynamic effect of the steel suspension box generally increases,but the increasing magnitude is relatively smaller.In the actual projects,it is suggested that a magnification coefficient of 1.15 should be multiplied on the basis of calculation results of static force,or the characteristic wave method should be directly used to carry out the calculation.更多还原