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振动特性对结构参数的灵敏度对结构设计和诊断十分重要。用一阶随机摄动法建立悬索桥随机特征值问题的基本方程，求其动力特性对结构参数的灵敏度矩阵，并得到随机特征值的统计特征。结构随机参数按局部平均随机场理论离散。取主缆，桥塔和加劲梁的弹性模量和质量密度为随机场。在此基础上计算了青马桥自振频率的统计特征和对随机参数的灵敏度矩阵，并由此讨论随机参数对青马桥自振频率的影响。发现结构参数对悬索桥自振频率影响不显著，但自振频率对不同部位的参数的灵敏度系数有量级上的差别。
The sensitivity of the vibration characteristics to the structural parameters is very important for structural design and diagnosis. The first order stochastic perturbation method is used to establish the basic equation of the random eigenvalue problem of the suspension bridge and the sensitivity matrix of the dynamic characteristics to the structural parameters is obtained and the statistical characteristics of the stochastic eigenvalues are obtained. The random parameters of the structure are dispersed according to the local average random field theory. Take the main cable, bridge tower and stiffener elastic modulus and mass density random field. On this basis, the statistical characteristics of the natural frequency of the Tsing Ma Bridge and the sensitivity matrix of the random parameters are calculated, and the influence of the random parameters on the natural frequency of the Tsing Ma Bridge is discussed. It is found that the structural parameters have no significant effect on the natural frequencies of the suspension bridges. However, the sensitivity coefficients of natural frequencies have different order of magnitude on the parameters of different parts.