Vertical Displacement of a Single Pile Due to Axial & Lateral Loads

Abstract

Pile foundation supports the upper structure to the subgrade, generally vertical loads. Still, if horizontal loads are very dominant, such as bridges, tall buildings, and tower structures, it must be calculated. Pile foundations with combined loads are generally analyzed. The axial load is first to determine the axial carrying capacity and vertical displacement, then the lateral load to determine the lateral bearing capacity and lateral deflection. In the field, the two loads work together/simulant. In Indonesia, loading tests do not simultaneously, so in construction, it does not account for the additional vertical displacement and lateral deflection due to the load that works simulant. However, there has been an association in ASTM D3966-07 about the simulant loading test. This research will investigate the analysis and experimental laboratory, the effect of vertical displacement on a single pile foundation, as the effect of combined loads. Also, it gets a relationship that can be used as a reference for analyzing additional vertical displacement due to combined loads on pile foundations based on available independent loading test. The research will be divided into two stages. Stage I is an analysis with the Finite Element Method (FEM) approach. Phase II is a laboratory model experimental test, which is inbox (100x100x80) cm3 filled silty sand soil as an illustration of conditions in the field, single pile foundation using steel with a length of 50cm and 60cm, the diameter of 1.5cm and 2cm, with axial and lateral load variations and combined loads. The results obtained show that after adding vertical load (Pu) about 5x, lateral load (Hu) on (Pu/Hu > 5) and the vertical displacement stays like the loading test until it collapses. Another (Pu/Hu ≤ 5), the lateral load, will increase the significant vertical movement due to the combination load. With axial load five times greater than lateral load, there is no increase in vertical displacement. Still, at an axial load less than five times the lateral load, there is an increase in vertical displacement that needs to be considered.