为研究盾构隧道壁后注浆压力变化、浆液特性、注浆扩散范围对模型响应（如地表沉降、地层损失率等）的影响，研究设计了一种新型模型试验装置，用于模拟浅埋隧道掘进过程中衬砌管片在注浆过程中的变化。该装置包括隧道收敛、加载-卸载、注浆和样品制备系统，创新点为注浆过程中管片能够在竖直方向自由移动，更加符合工程实际。试验结果表明： 1）允许隧道位移工况下浆液压力变化趋势不同于传统模型隧道固定工况的结果，试验中浆液压力传感器峰值约为不允许隧道位移工况下的5倍； 2）增大注浆压力，获得更高的浆液压力传感器峰值，研究试验工况中地表地层损失率最高能减小0.71%； 3）增大注浆量，会改变浆液压力变化趋势，地表地层损失率最高能减小0.67%； 4）改变注浆方式，会改变浆液扩散形式，地表地层损失率最高能减小0.44%。
To investigate the effects
of grouting pressure, slurry properties, and grouting diffusion range on the
model responses (surface settlement and ground loss) of shallow tunnels, an
innovative model test device is developed. This device can simulate the variation
of lining segment of the shallow tunnels during grouting. The device includes
systems of tunnel convergence, loading-unloading,
grouting, and sample preparation. The originality of this device is that the
model lining can move freely in the vertical direction during the grouting
process, which is more in line with the engineering reality. The experimental
results show the following: (1) The slurry pressure evolution pattern under
allowable tunnel displacement is different from that of conventional model with
fixed conditions. To be specific, the peak value of the slurry pressure under
the allowable tunnel displacement is about 5 times that under the conventional
tunnel model with fixed conditions. (2) With increasing grouting pressure, a
higher peak value of the slurry pressure is obtained and the surface volume
loss rate is reduced by up to 0.71% in the present study. (3) With increasing
grouting volume, the trend of the slurry pressure turns different and the
ground loss ratio is reduced by up to 0.67%. (4) When using different grouting
methods, the form of the slurry diffusion becomes different and the ground loss
ratio decreases by up to 0.44%.
