A week of disruption due to repairs to a subsided road foundation? Not any more, if the province of North Holland has its way. A trial using a rapid injection method proved successful in repairing a bus lane in Hoofddorp. The subsided support plates were raised within 1.5 hours by injecting expansion resin.
The bus lane in Hoofddorp runs over a viaduct. Beneath the lane lie concrete slabs that bridge the difference in settlement between the viaduct and the rest of the bus lane, ensuring a smooth transition. In soft subsoil – a common occurrence in the Netherlands – transition slabs often subside. This creates bumps in the tarmac. In Hoofddorp, too, the tarmac on the bus lane had been damaged by subsided transition slabs.
Reduces disruption and saves costs
Repairing subsidence using traditional methods takes at least five days and causes disruption to the local area and road users. Injecting expansion resin beneath the expansion joint works much faster, as this material cures rapidly. The method therefore reduces disruption and saves costs.
Successful trial
Following successful applications of expansion resin at locations including level crossings, the province of North Holland decided to trial the injection method for repairing the bus lane in Hoofddorp. They succeeded in returning the buffer plates to their original position within 1.5 hours. Within 24 hours, the tarmac had also been repaired and buses were once again travelling along the lane. Given the success at this location, the province intends to apply the method to other projects as well.
