盾构隧道同步注浆浆液压力变化规律研究

基于浆液流体的连续方程和运动方程,建立了浆液刚进入盾尾空隙时的环向压力分布模型;并推导了在距离注浆孔较远距离处的浆液压力梯度与上浮力的关系式。结合实际工程监测数据验证了理论分析的合理性。分析结果表明:盾构机推进时,注浆点附近的浆液环向压力分布主要由注浆孔位置和注浆孔压力及浆液重度决定;停止推进时,浆液在固结效应下压力逐渐消散,竖直方向上压力梯度逐渐减小;随着远离注浆点,浆液的压力梯度逐步减小并趋于稳定,稳定时的压力梯度主要由上浮力的大小决定。

Change of Grout Pressure During Simultaneous Grouting of Shield Tunnel

Based on the continuity equations and momentum equations of grout fluid, a circumferential pressure distribution model, when grout was just entered into shield tail void, was established. And the relation between grout pressure gradients where grout was far away from the injection points and buoyancy forces was derived. The validity of the theoretical analysis was certified by the monitoring results obtained from certain practical engineering cases. The results show that during drilling, the pressure close to the injection points was dominated by the location of injection openings, grouting pressure and grout density. During standstill, grout pressure decreased gradually because of consolidation and the vertical pressure gradient decreased gradually. Grout pressure gradient decreased gradually when grout was far away from the injection points and the stabilized pressure gradient was governed by buoyancy forces.