本文介绍一种简便易行的动力模型试验方法——直接摄影法,它具有直观性强、振动图形一目了然的特点。应用这种方法曾成功地测定了拱坝、重力坝等大体积弹性建筑物的各阶频率、振型并据以计算振型应力。文中给出了分析实验结果的方法,并探讨了模型材料的泊松比和可能存在的几何非线性因素对振动频率和振型的影响及其改正方法。 This article describes a simple and easy method of dynamic model test - direct photography, it has a strong intuitive, vibration pattern at a glance. Using this method, the frequencies and mode shapes of large-scale elastic buildings such as arch dams and gravity dams have been successfully measured and the vibration mode stress has been calculated. The method of analyzing the experimental results is given in this paper. The influence of the Poisson’s ratio of the model materials and possible geometric nonlinear factors on the vibration frequency and mode shape and its correction method are discussed.