斜拱结构的强度及经济性探讨

Discussion on Strength and Economy Efficiency of Skew Arch

探讨了竖直拱两种衍生形式——斜拱和出平面有约束斜梁的强度及经济性问题。通过斜拱平面内和平面外内力的比较,可以得出当跨度较大时,不宜采用斜拱面结构;通过竖直拱和斜拱在不同跨度下的应力比较,可以充分肯定竖直拱的经济性;通过斜拱在不同倾斜角下应力的比较,可以得出当角从45°增大到55°就可以大大减小斜拱出平面的内力。竖直拱的另一种衍生结构——出平面有约束斜梁,通过增加斜拱出平面方向的位移约束可以大大改善斜拱的内力,同时可以满足经济性的要求。最后还讨论了斜拱的曲线形状对结构内力的影响。

Two instances of structural style both deriving from the vertical beam with out-plane displacement constraints are discussed in terms of the arch,i, e. the skew arch and the skew strength and the economy efficiency. By comparing the in-plane internal force and the out-plane internal force within the skew arch, it can be concluded that the skew arch is not a suitable structure style when the span length is quite large. The comparison between the stress in the vertical arch and that in the skew arch with different span lengths proves that the vertical arch has better economy efficiency than the skew arch. The out-plane internal force can be reduced significantly with the tilt angle of the skew arch raising from 45°to 55°through the stress analysis of various skew arches with different tilt angles. The analysis of the skew beam with out-plane displacement constraints derived from the vertical arch indicates that the internal force in the skew arch can be reduced remarkably by adding the displace- ment constraint in its out-plane ,and the economy efficiency can increase significantly. The effect of the skew arch curve on the internal force in the structure is also discussed.