Response of Framed Buildings on Raft Foundations to Tunneling

Abstract

This paper investigates the response of framed buildings on raft foundations to tunnel construction using geotechnical centrifuge testing. Five framed building models were considered, and the influence of building configuration, weight, eccentricity, and soil density were evaluated. Soil and foundation displacements, frame deformed shape, maximum structure deformation parameters (deflection ratios and angular distortions), and associated modification factors are illustrated. Results indicate that unlike equivalent isotropic plates, framed buildings primarily exhibit shear behavior and a semi-flexible response. Building deformed shapes indicate that angular/shear distortions (considering bay slope and local tilt) are more appropriate for quantifying framed building distortions than deflection ratios. A relative stiffness parameter is suggested to relate maximum angular distortions to the greenfield settlement slope. Moreover, the efficiency of the available relative stiffness parameters for the deflection ratio modification factors is confirmed. Limitations of the equivalent plate approach and practical implications of the results for framed buildings are discussed.