Even though sewers have been conventionally designed to prevent from sediment deposition using a specified minimum velocity or shear stress at a particular depth of flow or with a particular frequency of occurrence, it was appreciated that these methods do not consider the characteristics and concentration of the sediment and the specific hydraulic conditions of the sewer with sediment. In this study, a densimetric Froude number formula was suggested considering particle diameter and volumetric concentration of the sediment as well as flow depth and flowrate, based on several domestic field inspections, which was compared with other formulas proposed by previous investigators. When the sediment concentration was not considered, the calibration coefficient of 0.125-1.5 to the densimetric Froude numbers of this study was needed to obtain the similar ones with previous investigators’. For the densimetric Froude number formula obtained with consideration of sediment concentration, the exponent value of term Cv was almost the same as that of previous results and that of d50/Rh was similar for Fr < 2.2.

ABSTRACT
1. 서 론
2. 자가세정 하수관로의 설계방법
3. 현장 실험
4. 결과 및 고찰
    4.1 침전물의 체적농도의 변화에 따른 밀도프루드수의 변화
    4.2 현장실험 결과값을 이용한 밀도 Froude수 공식 도출
5. 결 론
References

• 박규홍(중앙대학교 사회기반시스템공학부) | Kyoohong Park (Department of Civil Engineering, Chung-Ang University) Corresponding author
• 이태훈(중앙대학교 사회기반시스템공학부) | Taehoon Lee (Department of Civil Engineering, Chung-Ang University)
• 유순유(한국산업기술대학교 지식융합학부) | Soonyu Yu (Department of Consilience, ADD at Korea Polytechnic University)
• 강병준(중앙대학교 사회기반시스템공학부) | Byongjun Kang (Department of Civil Engineering, Chung-Ang University)
• 현기림(중앙대학교 사회기반시스템공학부) | Kirim Hyun (Department of Civil Engineering, Chung-Ang University)