The jacking force is composed of the head resistance and friction resistance of the pipe wall, and the for-mer is generally considered a constant value and the latter increases with an increase of jacking distance. The exist-ing formula for calculating friction resistance of the pipe wall of a rectangular jacking pipe is analyzed, and it is found that the quasi-rectangle is simplified and the pressure arch effect is not considered under deep depth condi-tions in the existing theoretical formulas, which results in great differences between the calculation values and the measured values. The earth pillar theory and the M. M. Promojiyfakonov pressure arch theory are adopted to deduce a theoretical formula for calculating the friction resistance of the pipe wall of shallow-buried and deep-buried qua-si-rectangular jacking pipes. Based on the case study, the friction resistance of the pipe wall calculated by the for-mula given in the specification is relatively conservative when the pipe-jacking tunnel is located in favorable stra-tum and has a large overburden with the forming of a pressure arch, while the results calculated by the formula pro-posed in this paper are more reasonable.%顶管顶推力由迎面阻力和管壁摩阻力组成,迎面阻力一般可认为是一个定值,而管壁摩阻力则随着顶进距离的增加而增大.文章通过分析已有的矩形顶管管壁摩阻力计算公式,发现现有的理论公式均是将仿矩形简化为矩形以及在深埋条件下未考虑压力拱效应,计算值与实测值相差较大.鉴于此,通过运用土柱理论和普氏压力拱理论,推出了浅埋和深埋仿矩形顶管管壁摩阻力的理论公式.通过算例分析发现,当顶管隧道所处地层较好,埋深较大,且能够形成压力拱时,按规范中的计算公式所计算出的管壁摩阻力相对保守,按本文推导出的公式的计算结果较为合理.
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