2方向接合円形落差マンホール部の構造改善に関する実験的研究

抄録

The energy loss at manholes is often compared with the friction loss of pipes under surcharge flow. One of the methods to avoid inundation is the reduction in energy loss at storm sewer manholes. The purpose of this study is to develop new types of manhole structure for energy loss reduction. Experiments were carried out by using five types of manhole; Type A with straight-through pipes as used currently in Japan, Type B with a guide-cover on the invert of Type A, Type C with 90°Cbending pipes as also used currently in Japan, Type D with an improved invert profile of Type C, and Type E with full-benching of Type D. The experimental results showed that the energy losses for Types B, D and E considerably decreased than the other Types.