Journal of Korean Society of Agricultural Engineers ISSN:1738-3692(Print) 2093-7709(Online) 한국농공학회논문집

Due to the increasing frequency of extreme weather events, the importance of protected horticulture is being emphasized. In single-span greenhouses, continuous pipe foundations are used to enhance uplift resistance. Although the uplift behavior of continuous pipe foundations has been investigated in several studies, time-dependent effects have not yet been considered. Since construction-induced soil disturbance requires a certain period of time to stabilize, especially during the early stages after installation, it is important to clarify the time-dependent variation in uplift resistance. Therefore, this study analyzed the time-dependent behavior of continuous pipe foundations through in-situ uplift load tests. Continuous pipe foundations were constructed with two initial compaction conditions (2-layer and 4-layer compaction), and ultimate uplift capacity was evaluated on the day of construction, and 8, 21, and 76 days after construction. As a result, the ultimate uplift capacity showed a clear increasing trend up to 21 days compared with the day of construction. In addition, an increase in field dry unit weight and a pronounced decreasing trend in the Dynamic Cone Penetration Index (DCPI) were observed up to 21 days. These findings quantify how uplift resistance changes over time under different initial compaction conditions. This study provides useful data for stable, rational foundation design and construction management of disaster-resilient greenhouses.