Iterative Approach for Analyzing Jointed Pipeline Response Considering Pipeline‐Soil Gap Induced by Down‐Crossing Tunnel

In underground space engineering, the down‐crossing of a tunnel beneath an existing pipeline often leads to soil settlement beneath the pipeline, creating a gap between the pipeline and the soil. This can result in the loss of local support under the pipeline, significantly decreasing its safety and reliability. To analyze the effects of such gaps on pipelines, this study proposes a matrix transfer and iteration approach based on a discontinuous Timoshenko beam theory, aiming to evaluate the mechanical response of pipelines due to pipeline‐soil gap. Through the comparisons with centrifuge model tests, the accuracy and correctness of this approach are validated. Finally, a parameter analysis is conducted to exhibit the influence of ground loss volume, the trough width parameter, eccentricity, shear layer thickness, pipeline‐tunnel clearance ratio, and relative stiffness between the pipeline and soil on the pipeline responses. Based on the analysis results, some recommendations for practical engineering are provided.