Assessment of Construction Impact on Utilities affected by Settlements due to Tunnelling
Ground movements are affecting buried pipe utilities in many different ways. The paper discusses and in detail explains the application of approaches presented in respective technical literature related to the assessment construction impact of buried pipelines subjected to settlements. Although, most of this literature is from the late 1980s and 1990s, these papers are still very relevant, as they present very practical and useful approaches and methods for assessments to derive bending and axial strains. Most of these approaches are based on the volume loss approach, as it offers very quick and versatile spreadsheet-based assessment of many utilities in varying geometrical situations. Previous papers always dealt with utilities either crossing perpendicularly or running parallel to the tunnel drive. This paper presents and discusses an approach, which allows assessment of construction impact for utilities crossing at arbitrary angles. This approach will also eliminate the previous limitation of a pipe extending sufficiently beyond the zone of influence. The paper also contains enough mathematical details of this approach, which together with the stated references, will enable the interested reader to develop respective calculation spreadsheet(s) for him/herself.