抄録
We treat the frequency of the natural horizontal bending vibrations when a symmetrical trapezidal girder bent supports a load, neglecting self-mass of girder bent in 2 cases, i. e. one is girder bent with fixed-end columns and another with pin-end columns. Then changes of frequency due to the change of the angle of columns and the ratio of the height to the length of horizontal beam, etc. are discussed.
Moreover we calculate the effect of the self-mass of the trapezidal girder bent on the frequency.
