为探讨某隧道工程盾尾渗漏事故原因，设计一套可模拟不同盾尾间隙工况条件下的盾尾刷加载模拟试验装置，并对该工程盾尾钢丝刷在不同的盾尾间隙下的工作状态（加载变形和破坏模式）进行试验研究。试验结果表明： 1）在相同作用压力下，随着盾尾间隙的增大，盾尾钢丝刷抗变形能力逐步降低。2）在盾尾间隙较小时，盾尾刷前后钢板的协调变形能力较强，盾尾钢丝刷能承受较大荷载； 当盾构间隙增大到一定程度时，仅较小的荷载即可造成盾尾钢丝刷钢板产生较大的变形，导致盾尾刷保护钢板产生塑性变形，甚至根部断裂，破坏后的盾尾刷钢丝外翻，从而导致盾尾密封失效。

The factors leading to the leakage accident of the shield tail of a tunnel project are determined by designing a suite of simulation test devices for loading of the shield tail brush under different conditions. The working states of loading deformation and failure modes under different shield tail clearances are investigated. The results reveal that (1) for a given pressure, the antideformation capacity of the shield tail brush decreases with increasing shield tail clearance. (2) When the clearance is small, the brush can withstand large loads without damage. When the clearance of the shield tail increases to a certain extent, a small load can cause a large deformation of the steel plate comprising the brush. This leads to plastic deformation of the plate or root fracture. Furthermore, the damaged wire of the shield tail brush evaginates, leading to sealing failure of the shield tail.