NUMERICAL STUDY OF THE INTERACTION BETWEEN STRUTTED EXCAVATIONS AND ADJACENT PILES

Abstract

This research comprises the use of 2D numerical modeling to evaluate the performance of strutted excavations and their effect on adjacent existing piles. PLAXIS 2D was adopted, as a modeling tool, in this research. A verification model was used to validate the simulation of a documented case study. The simulated case study included the construction of a cut-and-cover tunnel as part of a new Mass Rapid Transit line in Singapore. The results of the numerical study were compared to the full-scale field measurements. Afterward, the analysis was extended to investigate the interaction between the retaining system and existing piles located behind the retaining wall. A parametric study was conducted to examine the effect of different parameters, including excavation depth (H = 4 m to 16 m), retaining wall-length (L = 8 m to 40 m), spacing between struts (S = 2 m to 4 m), axial loads on pile (N = 0 kN to 1000 kN), and the horizontal distance between the existing pile and the retaining wall (x = 1.5 m to 40 m). The structural performance of the retaining wall and adjacent piles are reported in terms of horizontal displacements and bending moments.