Elastoplastic Solutions to Predict Tunneling-Induced Load Redistribution and Deformation of Surface Structures

Abstract

In this paper, an elastoplastic two-stage analysis method is proposed to model tunneling-induced soil-structure interaction and incorporated into a computer program called Analysis of Structural Response to Excavation (ASRE). This solution allows considering both vertical and horizontal greenfield ground movements, gap formation and slippage, continuous or isolated foundations, and a variety of structural configurations and loading conditions. After introducing the proposed formulation, the model predictions are first compared with previously published data for validation. Then, to isolate the effects of various structural characteristics (relative beam-column stiffness, presence of a ground-level slab, column height, and number of stories) and foundation types (continuous versus isolated), several example structures are analyzed. Results demonstrate the value of the proposed analysis method to study a broad range of building characteristics very quickly, and show how the soil-structure interaction occurring due to underground excavations is altered by both foundation and superstructure configurations. In particular, the difference in behavior between equivalent simple beams and framed structures on separated footings is clarified.