高水压盾构隧道新型管片接缝密封性试验研究

Experimental Study on Sealing Performance of New Segment Joints in High Water Pressure Shield Tunnels

针对高水压盾构隧道新型管片接缝的密封性能,通过遇水膨胀橡胶密封垫水密性试验和耐久性试验,研究了管片接缝的防水性能,并获得了反映遇水膨胀橡胶密封垫防水性能和耐久性能的关键参数,以期为同类型隧道在轨道交通中的应用和推广提供技术支持。结果显示,对于遇水膨胀橡胶密封垫水密性试验,在双缝张开量3 mm、错缝2 mm工况下,水密性试验全部满足设计水压值0.8 MPa,且极限压力分别为1.5 MPa、1.5 MPa和1.0 MPa,有较大的安全储备;对于遇水膨胀橡胶密封垫耐久性水密试验,在双缝张开量3 mm、错缝2 mm工况下,有两组试验达到设计水压,极限压力分别为1.4 MPa和1.3 MPa,老化后的极限承压能力略有下降。

With regard to the sealing performance of a new type of segment joint in high water pressure shield tunnels,the waterproofing performance of the segment joints is studied through water tightness and durability tests of hydro-expansive rubber sealing gasket,and key parameters reflecting the waterproofing and durability performance of hydro-expansive rubber sealing gaskets are obtained,which can provide technical support for the application and promotion of similar tunnels in rail transit.The results show that for the water tightness test of the hydro-expansive rubber sealing gasket,under the working conditions of double seam opening of 3 mm and staggered seam of 2 mm,all the water tightness tests meet the designed water pressure value of 0.8 MPa,and the ultimate pressures are 1.5 MPa,1.5 MPa,and 1.0 MPa respectively,which hasa large safety reserve;for the water-tight durability test of the hydro-expansive rubber sealing gasket,two sets of tests reached the designed water pressure under the working conditions of double seam opening of 3 mm and staggered seam of 2 mm,with ultimate pressures of 1.4 MPa and 1.3 MPa respectively,and the ultimate pressure bearing capacity slightly decreased after aging.