针对桥面不平整度对冲击系数的影响，采用自编程序，模拟计算了一定量不平整度样本下混凝土梁式桥的冲击系数。结果表明，即使同等级不平整度影响下的冲击系数也具有离散性，现行的不平整度能量谱密度分级法用于冲击系数的计算具有一定的局限性;对不平整度样本所引起的冲击系数集合进行统计分析，结果表明，同等级、具有独立同分布相位角的不平整度样本引起的冲击系数集合服从正态分布。针对连续车队对冲击系数的影响，提出了一种采用延时叠加法计算适应度值的遗传算法，该算法可减少车桥耦合振动计算工作量，高效地对车队中车辆间距进行优化分析，得到车队作用下桥梁最大冲击系数及相应的车队布置。

Aiming at influences of bridge deck unevenness on bridge DAF, DAF values of a concrete girder bridge caused by a certain amount of unevenness samples were calculated with a self-compiled program. The results showed that the bridge’s DAF values caused by unevenness samples with the same grade are also discrete; the existing unevenness energy PSD classification method has a certain limitation during its being used in calculating the bridge’s DAF. Statistical analysis was conducted for the DAF set caused by unevenness samples. The results showed that the DAF set caused by unevenness samples with the same grade and independent phase angle of the same distribution obey the normal distribution; aiming at effects of vehicle string on the bridge’s DAF, a genetic algorithm for calculation of fitness with the delay superposition method was proposed. It was shown that this algorithm can be used to reduce the calculation amount of vehicle-bridge coupled vibration, effectively do the optimization analysis for vehicle spacing in a vehicle string, and obtain the bridge’s largest DAF under action of vehicle string and the corresponding vehicle string arrangement.