为研究大直径顶管在深埋高水压工况下的管节荷载变化，结合佛山市电力隧道顶管工程，对顶管施工过程中管节荷载、孔隙水压力进行实测分析，并比较现行各规范理论计算结果和实测管节荷载的区别，推导在注浆状态下管节荷载的计算方法。监测数据及计算结果表明： 1）管节荷载在管壁四周分布较均匀，管节顶部荷载的变化受注浆压力影响较小，管节底部荷载与注浆压力变化基本一致，且管节底部荷载变化大于注浆压力的变化； 2）管土接触状态在注浆顶进过程中符合隧洞稳定假设，顶进结束停止注浆后更符合管土全接触假设； 3）在注浆状态下，各规范计算的管节荷载相比实测值较小，采用太沙基被动土拱理论推导的管节荷载计算模型更加合理。
To study the change in the segment load of largediameter
pipe jacking under deepburied and high water pressure
conditions, a case study is conducted on the pipejacking
project of a power tunnel in Foshan, China. Further, the segment load and pore
water pressure of the segment during pipejacking
construction are measured and analyzed, and the results are compared with the
theoretical calculation results in the current specifications. Then, the
calculation method of segment load under grouting condition is deduced. The
monitoring data and calculation results show the following. (1) The joint load
of the segment is evenly distributed around the pipe wall, the top load is less
affected by the grouting pressure, the bottom load accords with the grouting
pressure, and the change of the bottom load is greater than that of the
grouting pressure. (2) The state of pipesoil contact
accords with the tunnel stability assumption during grouting jacking, and it
fully accords with the pipesoil interaction assumption
when grouting stops at the end of jacking. (3) Under the grouting condition,
the segment load calculated by each specification is smaller than the measured
values, and the pipe load calculation model by Terzaghi passive soil arch model
is more reasonable.
