GRP (Glass fiber reinforced polymer plastic) pipes are classified into flexible pipe category because of the structural characteristics of GRP pipes buried underground. Moreover, the ring deflection of GRP pipe is affected by the certain factors such as pipe stiffness, the modulus of soil reaction of backfill materials, and bedding conditions. In this study, we investigated the structural characteristics of the GRP pipes buried underground considering the soil-pipe interaction including bedding angle, pipe stiffness, and soil density used as a backfill material. From this parametric study, it was found that the soil density used for the backfill is the most important factor relating to the ring deflection of the buried GRP pipe.

ABSTRACT
 1. 서 론
 2. 연성관의 단기 관변형
 3. 설계지표에 대한 매개변수해석
 4. 결 론
 참고 문헌

• 최진우(홍익대학교 토목공학과) | Choi Jin-Woo
• 주형중((주)아이시스이엔씨) | Joo Hyung-Joong
• 윤순종(홍익대학교 토목공학과) | Yoon Soon-Jong