End-Bearing Capacity of Embedded Piles with Inclined-Base Plate: Laboratory Model Tests

Abstract

The objective of this study is to investigate the effects of an inclined base plate on the end bearing capacity of embedded piles and soil behavior below a pile base according to the vertical stress and inclination angle of the base plate. Two types of model piles were prepared: A conventional pile with a flat base plate with a diameter of 50 mm and piles with an inclined base plate with a diameter of 56 mm. Load tests were conducted using model piles with a diameter of 50 mm incorporated with load cells and bender elements in a calibration chamber. The end bearing capacity, unit end bearing capacity, and shear wave velocity increase for all model piles with an increase in the vertical stress and in the inclination angle. The increment in the end bearing capacity may result from the increased projected area, the increased contact area between the inclined base plate and soil, and increased horizontal effective stress. The unit end bearing capacity also demonstrates a good relationship with the shear wave velocity, which is a function of the horizontal effective stress below the pile base. This study suggests that piles with inclined base plates may be effectively used in the embedded pile method to improve the end bearing capacity. © 2020 American Society of Civil Engineers.