Metrolink Railroad Stabilization Emergency Repair

The Challenge

Stabilize track without damaging nearby sewer main.

A 20′ x 10′ section of rail track was experiencing significant subsidence due to the infiltration of fines into the 54″ sewer main located below the track. The settling track created an urgent need for repairs to prevent the risk of a potential collapse, which could disrupt Metrolink services and pose safety hazards. The subsidence required swift action to stabilize the affected area and avoid compromising the infrastructure further.

Key Facts

The Solution

Stabilize soils under tracks by injecting polymer

To stabilize the base soils, the polymer was used due to its quick cure time, which minimized downtime and its hydro-insensitivity, making it ideal for conditions with standing water. The injection was carried out at depths of -5’, -10’, and -15’ on 5’ intervals to ensure that the upper soil strata were effectively stabilized, preventing subsidence and mitigating future soil loss.

The Impact

Quickly stabilized Metrolink railroad with no downtime.

The project was completed efficiently within just 2 shifts, with Groundwork’s team on-site within 3 days of the initial site visit to begin repairs. Pre- and post-DCP tests confirmed that the polymer injection significantly increased the soil density, ensuring long-term stabilization of the track base. Metrolink was fully satisfied with the professionalism of the Groundworks team, the timeliness of the repair, and the fact that there was no downtime due to the fast-curing nature of the polymer and the efficiency of the crew.