This paper analyzed design bearing capacities of pile foundations strengthened by pre-loading method for vertical expansion. The bearing capacities were investigated for two different pre-loading strategies: (1) after partial removals of structural/non-structural elements (e.g. finish, masonry wall etc.); and (2) after vertical expansions. Based on the numerical studies, more than 60% of the existing piles exceeded the design bearing capacities due to the difference of pre-loading strategies, which should be considered in structural design.

Abstract
 1. 서 론
 2. 수직증축 리모델링 시 말뚝 선재하 절차
 3. 해석결과
 4. 결 론

• 최기선(한국건설기술연구원) | Choi, Ki Sun 교신저자
• 신지욱(한국건설기술연구원) | Shin, Ji Uk
• 김민선(한국건설기술연구원) | Kim, Min Sun
• 이현지(한국건설기술연구원) | Lee, Hyun Jee
• 유영찬(한국건설기술연구원) | You, Young Chan