TYPE | Transportation Infrastructure | LOCATION | Suzhou |
MATERIAL | KIN FLAGO DR，JOYA FN EZFLEX，KINJOYA FM VERDASYS | YEAR | 2024 |
AREA | 130000㎡ |
Background
As a key component ushering in Suzhou’s “loop line era,” Line 8 is entirely underground, crossing multiple water bodies including Loujiang River, Jinji Lake, and Yangcheng Lake. The geological conditions are complex, requiring high standards of anti-seepage and crack resistance. The project leveraged new materials, processes, and technologies to establish a comprehensive anti-cracking and anti-seepage system for the structure’s full lifecycle, aiming for a “watertight” result. Crossing water bodies presented high groundwater pressure and leakage risks, and some sections required tunneling beneath existing operating lines, demanding strict control of construction disturbance.
Solution
The project primarily used the KIN FLAGO DR HDPE pre-applied waterproofing membrane. For the station roof slab, considering the load from backfill and potential landscaping, a composite system was applied using JOYA FN EZFLEX non-curing waterproofing coating and KINJOYA FM VERDASYS SBS root-resistant waterproofing membrane. The KIN FLAGO DR HDPE membrane utilizes a unique pre-applied, reverse-bonding method. Its specialized adhesive layer forms a strong chemical bond with the subsequent concrete pour, effectively eliminating water channeling and integrating the membrane with the structure. The JOYA FN EZFLEX coating exhibits excellent creep recovery and self-healing properties, maintaining a continuous seal even with minor structural movement. The KINJOYA FM VERDASYS membrane features a chemical root inhibitor that effectively prevents root penetration, ensuring long-term waterproofing performance for the roof slab under complex loading and environmental conditions.
Outcomes
The project successfully achieved a zero-leakage goal for the massive underground structure, establishing a benchmark for subway construction in high-water-pressure areas. A replicable, integrated solution combining crack resistance, anti-seepage, and intelligent control was developed, promoting technological advancement in rail transit construction. The line supports the formation of a combined loop with Suzhou Metro Line 3, enhancing transportation efficiency and urban capacity around the ancient city. Line 8 began trial operation in September 2024, marking Suzhou’s official entry into the “loop line era.”
