ABSTRACT
This paper presents the study of the effect on existing water supply tunnels due to adjacent pile row under loading by 3D finite element method (3D FEM). The study covers the piles with diameter of 0.5 m and 1.5 m, spacing of 3 m and 4.5 m and tunnels having diameter of 2.0 m and 4.45 m. The pile tip elevations and clearances (C) are varied in the analyses. The Metropolitan Waterworks Authority (MWA) tunnel data and properties of Bangkok subsoil are considered in 3D finite element analyse. The analysis results are shown in terms of both safety factor and maximum changes of tunnel diameter. The tunnel influence zone due to nearby pile row under loading is suggested from the findings in this study.
