耐高水压盾构用盾尾密封油脂及其性能表征

针对国内跨江越河等高水压(0.4~0.8 MPa)盾构施工所需盾尾密封油脂被进口产品垄断的难题，通过正交试验研究盾尾密封油脂各个配方组分之间的相互作用。结果表明: 1)增稠流变剂的引入，提供了层间距为5~10 nm的片层结构，为基础油和聚异丁烯提供了进入空间，实现了增稠分散，提高了耐高水压盾尾密封油脂的剪切流变性，保证了稠度与泵送性的平衡； 2) 不同尺度的天然可降解纤维与配方中其他组分形成复合纤维增强阻水结构，使得耐高水压盾尾密封油脂的水击穿压力达7 MPa，是进口产品的1.75倍。在实现盾尾密封油脂稠度和泵送性适中的同时，大大提高了盾尾密封油脂的抗水压密封性，为我国跨江越河等高水压复杂地层盾构用高端盾尾密封油脂的进一步研发与转化打下坚实的基础。

Property Characterization of Shield Tail Sealing Grease for High Water Pressure

The shield tunneling in high water pressure (0.4~0.8 MPa) when crossing the rivers in China is monopolized by imported shield tail sealing grease. Through orthogonal studies, the interaction of the sealing grease′s components is investigated to address this issue. The findings reveal the following: (1) By introducing a thickening rheological agent, the formula creates a lamellar structure with layers spaced 5~10 nm apart, giving base oil and polyisobutylene access space. This allows for the realization of thickening and dispersion, improves the shear rheology of shield tail sealing grease under high water pressure, and ensures the balance between consistency and pumpability. (2) By adding various scales of naturally degradable fibers and other ingredients to the formula, a composite reinforced water resistance structure is created, resulting in 7 MPa water breakdown pressure of highwater tightness pressure sealing grease, which is 1.75 times as much as the imported product. As a result, the reasonable consistency, and pumpability of shield tail sealing grease are achieved, and the water tightness is also significantly improved. It has laid a solid foundation for the further research, development, and transformation of high end shield tail sealing grease for shields in high water pressure and complex strata such as river crossings in China.