This report presents an experimental study with the aim of developing a horizontal fixture drainage branch system to facilitate liberal drainage planning for apartment housing while intending to verify system performance and discuss design techniques. Partly, the report verifies the performance of the combined drainage system, which is applied to the infill of long-lasting SI houses, and discusses the system design. To be more specific, first, the relation between carrying performance decline in the sewage system and the characteristics of drainage from sanitary fixtures, i.e. the biggest cause of drainage problems, was examined through experiments in the laboratory. Next, the abovementioned system was used on the actual super high-rise apartment building to carry out item-to-item system performance evaluation, using both simple and detailed methods which were explained in the previous report. The system design was also discussed.
