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通常的桥梁抖振分析借助于频域内的反应谱方法，因而局限于线性范围．近年来大跨度桥梁不断兴建，有必要在其风致抖振响应分析中计入结构几何非线性和有效攻角的影响．文中提出了一个桥梁抖振响应的非线性时程分析法．脉动风诱发的抖振力由计算机模拟为多个互相关的随机过程，自激力则表达为桥面运动和脉冲响应函数的卷积形式．在Ｎｅｗｍａｒｋ－β逐步积分算法中，考虑了结构的大变位以及瞬时有效攻角的变化．应用文中方法计算了两座悬索桥的抖振响应时程，并与风洞试验结果进行了对比．
The usual bridge chattering analysis is limited to the linear range by means of the spectral response method in the frequency domain. In recent years, the continuous construction of long-span bridges is necessary to include the influence of geometric nonlinearity and effective angle of attack in the wind-induced buffeting response analysis. In this paper, a nonlinear time-history analysis method of bridge chattering response is proposed. The flutter-induced buffeting force is simulated by computer as a number of cross-correlation random processes. The self-excitation is expressed as the convolution of deck motion and impulse response function. In the Newmark-β step-by-step integration algorithm, the structural large displacement and the change of instantaneous effective angle of attack are considered. The time-history of buffeting response of two suspension bridges is calculated by the method in this paper and compared with the results of wind tunnel test.