ASSESSMENT TO THE PILE BEARING CAPACITY OF INJECTION PILE BASED ON PILE DRIVING ANALYZER AND RE-INJECTION TEST RESULTS (CASE: EASTKAL PENAJAM PROJECT)

Abstract

Injection piling method was used as the main pile driving method at the three warehouses in the Eastkal Penajam
project, Kalimantan, Indonesia. The sub-soil compositions are dominated by clay and sandy soil with very soft to medium
consistencies. By using injection pile equipment, it is possible to measure the pile bearing capacity from the loading gauge.
Since the soil is dominated by clay, the friction capacity overtime will be improved. For that purpose, the piles were re-injected
again after 3, 10, 11, and 25 days. To establish the forecasting expression of pile bearing capacity enhancement for other piles,
non-linear regression analysis was performed. To verify the result, pile driving analyzer (PDA) test for selected piles was
carried out. The results from PDA test were further analyzed by using both direct fields reading in the PDA data logger and the
Case Pile Wave Analysis Program (CAPWAP). A linear regression analysis was carried out to complete the blank data due to
the field measurement limitation. In addition to the obtained field data, theoretical analysis of pile bearing capacity with Luciano
Decourt method is carried out. From the comparisons of all data, it can be concluded that re-injection pile method provides the
highest safety factor followed by PDA test, CAPWAP analysis, and theoretical design calculation with Luciano Decourt method.