LOAD-BEARING CAPACITY OF STEEL PIPE PILES IN CORAL GRAVELLY SAND CONSIDERING THE EFFECT OF HELICAL PLATE DISTANCE

Construction projects on geological grounds, particularly coral reefs, hold significant importance for national security, defense, and marine economic development. However, the application of new technologies and enhanced pile foundation structures in these projects has been limited. This study focuses on researching and evaluating the correlation between the load capacity of traditional steel pipe piles, which are supplemented with two helical plates, and the variations in the distance of these helical plates along the depth of the pile in coral gravelly-sand using Mohr-Coulomb model by finite element method. The results of this study conclude that the load-bearing capacity of piles with two helical plates is 2.1 to 3.3 times higher than that of traditional plain round piles. In addition, a calculation function for the load-bearing capacity of the improved steel single-pipe pile in relation to the appropriate distance for the helical plates is proposed. This function is essential for projects built under the geological conditions of coral and the typical hydrological properties found in the offshore seas and islands of Vietnam.