矩形顶管施工引起的地表变形特征与圆形顶管或盾构隧道存在显著差异。为了明确浅埋矩形顶管施工过程中的地表沉降特征以及顶管施工对下方既有盾构隧道的影响，根据现场矩形顶管施工监测结果，分析矩形顶管施工过程中地表的变形规律，以及顶管下方既有盾构隧道的变形情况。传统的 Peck 公式适用于圆形顶管或圆形盾构隧道，因此采用改进的 Peck 公式来描述矩形顶管引起的地表变形特征；根据现场监测分析顶管施工引起的地表变形、管线变形和下卧隧道沉降规律。研究表明：改进的 Peck 公式相比于传统的 Peck 公式可以准确描述矩形顶管施工引起的地表变形规律；顶管施工引起地表和上方管线的沉降规律是一致的，但与下卧隧道的变形规律存在显著差别。

Ground-surface deformation characteristics caused by jacked rectangular pipes differ from those caused by jackedcircular pipes or shield tunnels. The ground-settlement characteristics during the construction of a shallow-buried rectangularjacked pipe and its impact on the existing shield tunnel below the jacked pipe were clarified. Using the on-site monitoring resultsfrom jacked rectangular pipe construction, the deformation patterns of the ground surface during jacked rectangular pipeconstruction and the deformation of the existing shield tunnel below the jacked pipe were analyzed. The traditional Peck formulawas applied to circular pipe-jacking and circular shield tunnels; the improved Peck formula was used to describe the surfacedeformation caused by rectangular pipe-jacking. The surface deformation, pipeline deformation, and settlement pattern of thesubmerged tunnel caused by jacked pipes were analyzed based on field monitoring. The results show that the improved Peckformula can describe surface deformation caused by jacked rectangular pipes more accurately than the traditional Peck formula.The settlement patterns of the surface and pipeline caused by jacked pipes were consistent; however, there were differences inthe settlement patterns of the underlying tunnel.

U231

山西省自然科学基金项目(20210302123124)