Centrifuge Modeling Study of the Response of Piled Structures to Tunneling

Abstract

Tunneling beneath piled structures may compromise the stability and serviceability of the structure. The assessment of potential structure damage is a problem being faced by engineers across the globe. This paper presents the outcomes of a series of geotechnical centrifuge experiments designed to simulate the effect of excavating a tunnel beneath piled structures. The stiffness and weight effects of piled structures are examined independently using aluminum plates of varying stiffness (equivalent beam approach) and the addition of weights supported by aluminum piles. Greenfield displacement patterns and results from pile loading tests are also provided. The variation of structure displacement profiles with plate stiffness, weight, and tunnel volume loss are used to illustrate the main effects of tunnel-pile interaction and the contribution of the superstructure to the global tunnel-pile-structure interaction. Results indicate that piles have a detrimental role in tunnel-structure interaction problems, whereas the superstructure stiffness and weight can, respectively, reduce and increase structure distortions and settlements. Finally, the potential for structural damage is evaluated by comparing structure and greenfield deflection ratios as well as resulting modification factors. The paper presents a unique set of results and insights that provide valuable guidance to engineers working across the ground and structural engineering disciplines.