Phase 1 of the High Speed 2 rail line from London to the north will be built using a slab track trackbed system, a project leader has revealed.
Speaking at New Civil Engineer’s Future Tech Forum Mark Morris, High Speed 2’s director of asset management, railway operations said that the first London to Birmingham phase of the £32bn rail line was set to be built using a concrete slabtrack system, with a ballasted track bed set to be favoured for phase 2 from Birmingham to Leeds and Manchester.
“Phase 1 is looking like it’s going to be slab, with a decision in November,” he said. “Phase two looks like it’s going to be ballast.”
The choice of trackbed technology has been the subject of heated lobbying (New Civil Engineer March 2016). Proponents of slabtrack system have argued that ballasted track systems are noisy in use, expensive to maintain and even pose safety risks with individual ballast particles liable to be dislodged by the turbulent air caused by the passing high speed trains.
Conversely advocates of ballast-based systems point to the much lower cost and flexibility in use afforded by such systems.
Crossrail has used floating slab track
Both systems are in use on modern high speed railways around the world. Japanese, German and Dutch high speed rail networks tend to be based on concrete slab track. But French and Spanish lines tend to be ballasted.
The first phase of High Speed 2 arguably lends itself to slab track as a high proportion of the route is in tunnel – where slabtrack has already been specified as the trackbed of choice. This is a simple economic decision as slabtrack systems require a shallower base which means the tunnels can be smaller in internal diameter.