Xuzhou Metro Line 3 Waterproofing

Background

As the city’s north-south backbone line, Xuzhou Metro Line 3’s waterproofing spanned the entire Phase 1 and Phase 2 construction. It employed an integrated system of structural self-waterproofing, flexible external waterproofing, and reinforcement of critical details to ensure long-term stability and leak-free performance under complex hydrogeological conditions. The project’s overall strategy aimed for a “no seepage, no leakage, no damp stains” standard throughout the stations and tunnels.

Solution

This project primarily used KIN FLAGO DR HDPE pre-applied waterproofing membrane. For the station roof slab, a composite system using KINJOYA PU polyurethane coating and KIN PLUME VERDASYS PVC root-resistant membrane was employed. The KIN FLAGO DR HDPE membrane utilizes a pre-applied, reverse-bonding method, where its adhesive layer forms a chemical bond with the fresh concrete, integrating the membrane with the structure. For the roof slab, KINJOYA PU coating provides a continuous, seamless film with excellent elasticity and adhesion. The KIN PLUME VERDASYS PVC membrane offers superior root penetration resistance, durability, and weatherability. In the tunnel, the segment joints, a critical waterproofing point, were further reinforced in high-risk sections using specialized joint sealants supplied by KINJOYA, enhancing the watertightness of the segments.

Outcomes

Since operation began, the main structure has experienced no structural leaks, and the operational environment remains dry and stable. Underground waterproofing was successfully implemented in busy traffic areas like Xiayun Road and Beijing Road, minimizing disruption. A waterproofing technical approach suitable for the silty soil and sand strata common in Northern Jiangsu was developed, providing valuable experience for subsequent lines. This has supported Xuzhou Metro’s transition from focusing on construction to integrated construction and management, enhancing full-lifecycle operation and maintenance levels.