当前,一些民用房屋有逐渐采用大挑檐、高挑檐的趋向。这样,一方面建筑立面较为活泼、匀称;另一方面可兼作雨篷,使用上较为合理。但是,由于天沟荷载大大增加,因此其抗扭计算成为不可忽视的问题。民用住宅及办公楼等混合结构的平面布置,一般有横墙承重和纵墙承重两种型式。而天沟则有内天沟、女儿墙和外天沟兼作挑檐两种型式。本文讨论后者。天沟通常和天沟梁一起浇制。在结构计算中,不论是横墙承重还是纵墙承重,都会碰到这样两种情形t当天沟荷重(包括恒载和活载)对“0”点的倾复力矩,能被天沟梁的自重G_1及屋面荷重P_1对“0”点的稳定力矩所平衡并满足抗 At present, some civilian houses have gradually adopted provocative and high-profile tendencies. In this way, on the one hand, the facade of the building is more lively and well-proportioned; on the other hand, it can double as an awning, which is more reasonable in use. However, due to the greatly increased gutter load, its torsional calculation becomes a problem that cannot be ignored. The layout of civil buildings and office buildings and other mixed structures generally has two types: transverse wall bearing and vertical wall bearing. The gutter has two types: the Inner Gutter, the Parapet, and the Outer Gutter. This article discusses the latter. Gutters are usually cast with gutter beams. In the structural calculations, whether it is a cross wall load or a vertical wall load, there will be two situations in which the load moment of the ditch load (including the dead load and live load) against the “0” point can be guttered. The self-weight of the beam G_1 and the load of the roof P_1 on the stability point of the “0” point are balanced and satisfied