以崇明越江隧道为背景提出了泥水平衡盾构动态开挖模型试验的可行试验方案,并通过该试验对泥水平衡盾构开挖面平衡的机理,盾构推进时沉降的分布规律进行了研究。试验结果表明,泥水平衡盾构开挖面导致的地表沉降很大程度上取决于开挖过程中泥舱压力的浮动范围。通过将试验结果与楔形体模型理论计算的极限泥浆压力进行对比,得出了更加合理的极限泥浆压力浮动范围,有利于指导将来实际工程的施工。
With the increasing dimension of the slurry shields, more and more attention was paid to the face stability of slurry shields in recent years. A series of slurry shield model tests were carded out for the Yangtze River Tunnel of Shanghai. The results of the model tests were presented with particular emphasis on the balancing mechanism of slurry shields, the development of settlement at the excavating face and the limit slurry pressure. It was shown that settlements induced by the cutting face were mostly decided by the fluctuation of the slurry pressure in the chamber. The test results were compared with those of theoretical analysis of wedge model. The range of slurry pressure fluctuation was presented according to the test results.