Fire-resistant isolation layer for tunnel engineering, polyimide fabric resistant to moisture and high temperatures

Polyimide flame-retardant fabric for tunnel fire protection

Tunnels, as critical nodes in transportation hubs, face severe risks to personnel escape and rescue in case of fire, including high temperatures, dense smoke, and structural collapse. Traditional fire-resistant materials (such as rock wool and calcium silicate board) are prone to failure in humid environments. Polyimide flame-retardant fabric, with its high temperature resistance, moisture resistance, and lightweight properties, is becoming the preferred material for tunnel fire isolation layers.

Severe Challenges of Tunnel Fires

High-temperature environment: Temperatures during a fire can reach 1200℃, causing ordinary materials to melt and carbonize.

Dampness and corrosion: Water seepage and condensation in tunnels cause traditional fire-resistant layers to peel and degrade.

Mechanical load: Vehicle vibrations and structural deformation require materials with high strength and flexibility.

Construction convenience: Traditional fire-resistant boards are complex to install and have long construction periods, while polyimide fabric can be quickly laid.

Core Characteristics of Polyimide Flame-Retardant Fabric

1. Excellent flame-retardant performance

High-temperature non-dripping: It rapidly carbonizes when exposed to fire, forming a dense heat-insulating layer (oxygen index >38).

Wide temperature resistance range: Long-term resistance to 260℃, short-term resistance to 1000℃ high-temperature impact.

Low smoke and non-toxic: Releases only CO₂ and H₂O during combustion, environmentally friendly and non-toxic.

2. Excellent moisture resistance

Waterproof and mildew-proof: Stable molecular structure, maintaining performance even in environments with >95% humidity.

Resistance to hydrolysis and aging: After 30 days of immersion, the strength retention rate is >90% (traditional materials only 50%).

Salt spray corrosion resistance: Suitable for coastal tunnels, resisting chloride ion erosion.

3. High strength and flexibility

Tensile strength >80MPa, far exceeding ordinary fiberglass cloth (30MPa).

Tear resistance: Can withstand stress changes caused by micro-cracks in the tunnel structure.

Lightweight (surface density 500-800g/m²), reducing the load on the tunnel structure.

4. Convenient construction and low maintenance costs

Can be cut and sewn to fit curved tunnel structures.

Modular installation, saving 50% construction time compared to traditional fire-resistant boards.

Application of Polyimide Flame-Retardant Fabric in Tunnel Engineering

Tunnel vault fire protection layer

Function: Delays fire spread and prevents concrete from bursting.

Construction method: Fixed using anchoring + high-temperature adhesive, with overlaps ≥10cm at joints.

Fire curtain for escape routes

Function: Isolates smoke and high temperatures, ensuring safe evacuation.

Scheme: Polyimide fabric + steel frame, temperature resistance >600℃, manual/automatic opening and closing.

Fire wrapping for cable tunnels

Function: Prevents cable short circuits from causing fire spread.

Scheme: Customized sleeve-type fireproof fabric, high fire resistance rating.

Fireproof strip for tunnel expansion joints

Function: Adapts to tunnel thermal expansion and contraction while maintaining fire protection performance.

Scheme: High-elasticity polyimide composite material, elongation >30%.

With its superior high-temperature resistance, moisture resistance, and lightweight properties, polyimide flame-retardant fabric provides an effective solution to the pain points of traditional tunnel fire-resistant materials. It provides long-lasting, reliable, and low-maintenance fire protection for both new and renovated tunnels.

E-mail:
gdkaidun@163.com

Phone/WeChat:
86-131-3828-6677

Address:
Room 401, Building 21, No. 1, Keqing Road, Yundonghai Street, Sanshui District, Foshan City, Guangdong Province