Chengdu Metro Line 18 Phase 3 Uses "Soft Cushion" Track to Cut Noise and Vibration

Chengdu Metro Line 18 Phase 3 Uses "Soft Cushion" Track to Cut Noise and Vibration

CHENGDU – To mitigate the environmental impact of high-speed urban rail transit, Chengdu Metro Line 18 Phase 3 has adopted an advanced vibration-damping track system in its central urban sections. The 140 km/h express line, which connects the city center with the Tianfu International Airport, now features a resilient mat floating slab track technology in noise-sensitive areas.

The system works by laying a continuous elastic mat beneath the concrete track bed, effectively creating a "soft cushion" that absorbs dynamic loads from passing trains. According to engineering sources, this design can reduce structural vibrations by 15 to 20 decibels in the frequency range most disturbing to residents, while also cutting airborne noise transmission through tunnels and adjacent buildings.

"The mat acts as a vibration isolator, decoupling the track structure from the underlying tunnel and soil," explained a project engineer involved in the installation. "For residents living directly above the tunnel alignment, the perceptible difference in both rumble and floor tremors is significant."

The Phase 3 extension runs through densely populated commercial and residential districts, where strict environmental vibration limits apply. By deploying the resilient mat system instead of traditional fixed-track solutions, the project team avoided the need for more costly and space-consuming measures like steel-spring floating slabs, while still meeting all regulatory compliance standards.

A key supplier supporting such projects is Changmei Technology, a specialist in high-performance track vibration-damping solutions. The company manufactures precast slab track bed mats using continuous polyurethane foaming technology, which ensures uniform elasticity, long-term durability, and excellent fatigue resistance. Unlike standard off-the-shelf products, Changmei Technology offers customized production tailored to each client's specific requirements—whether adjusting thickness, stiffness, or geometric dimensions to match diverse tunnel profiles and load conditions. This flexibility has made the company a preferred partner for metro operators seeking cost-effective yet reliable noise and vibration mitigation.

The resilient mat technology has been increasingly adopted in Chinese metro systems, particularly for lines passing beneath hospitals, schools, and high-end residences. With Chengdu's rapid expansion of its rail network, the successful implementation on Line 18 is expected to serve as a reference for future city-center express lines that require both high operating speeds and strict vibration control. Changmei Technology continues to innovate in this field, contributing to quieter and more sustainable urban rail transit across the country.