基于压力拱理论的STS管幕顶力

Jacking Forces of Fringed STS Pipe Based on Stress Arch Theory

沈阳地铁九号线奥体中心站采用STS(steel tube slab)管幕法设计.基于压力拱理论,提出了根据管周土压力成因而分区域讨论的思路,推导了STS管幕法的顶管管周摩阻力公式.将理论计算结果和现场顶力观测数据进行了对比,得到较好的一致性.翼缘对顶力影响较大,不能采用简单叠加的方法,受"栓塞"作用影响,管侧土压力较小.利用现行国际设计规范计算了STS管幕顶力,由于现行规范未考虑翼缘板效应,规范计算结果比现场顶力观测数据偏小28%~40%.

The STS(steel tube slab)method was applied in the Olympic metro station project in Shenyang.Based on the pressure arch theory,a form ula of STS pipe-jacking friction resistance was deduced based on the cause of the earth pressure on the pipe week.The theoretical calculation result agrees w ell w ith the in-situ m onitoring data.The influence of the fringe on the jacking force is obvious and the calculation of which cannot use the simple superposition method.Affected by the"embolism"effect,the soil pressure on the tube side is small.The jacking force of STS pipe calculated according to the international design codes is smaller than the monitoring results by 28%~4 0%due to not taking the fringe effect into account.