New design charts for evaluating the damage potential to RC frame buildings adjacent to deep excavations

Purpose

Urban excavations are a cause for concern in terms of the probability of damage to nearby structures. In this study, various structural and excavation parameters were investigated to determine the probability of building damage during excavations.

Design/methodology/approach

Finite-element analysis software was used to develop a set of valid three-dimensional models. Models were developed to assess the effects of structural parameters (building height and position relative to the excavation site) and excavation parameters (depth and support system type) on the responses of the adjacent buildings.

Findings

The new design charts estimated the damage to reinforced concrete frame buildings during excavation by focusing on the angular distortion of the building, additional shear strain on the masonry walls and additional strain and stress on columns. This study showed that the probability of damage decreased as the distance between the building and the excavation increased. By contrast, it increased when the building was located at a distance equal to the excavation depth at its edge. According to this study, the axial stress caused by the excavation of building columns does not exceed 10.9% of the compressive strength of the concrete.

Originality/value

The proposed design charts can replace comparable charts and provide a deeper understanding of damage potential based on key parameters. These charts are more practical than previous charts with limited parameters.