Axial and lateral bearing capacity assessment of bored piles on medium-dense sand and liquefiable potential based on numerical simulation

Abstract

Liquefaction on bridges can cause structural failure due to loss of soil strength. The Showa Bridge that collapsed in 1964 Niigata earthquake was caused by buckling in piles as the soil layer liquefied and friction losses. In addition, there was a case of Palu IV bridge collapse in Indonesia during the recent 2018 Palu earthquake, which indicated have been affected by earthquakes and liquefaction. This study examines the reliability of the bored pile foundation of the Kretek 2 Bridge in Bantul Regency, Yogyakarta Special Region Province, for axial and lateral bearing capacity. This research method uses the soil structure interaction and 3D numerical simulation by Midas Civil and Midas GTS NX pile modeling. The pile driving analysis and lateral static loading test were also conducted, which can be compared to MIDAS results. For the foundation modeling result, there is an increase in axial and moment forces but a decrease in shear forces during liquefaction. While the lateral displacement increases significantly in the liquefaction state, foundation performance is still stable. Therefore, the foundation of the kretek 2 bridge is sufficient to support axial and lateral load both in a static state and a liquefaction state.