Modular Grade Crossing Repair, Millville, New Jersey

Modular grade crossing repair–Millville, New Jersey

Polyurethane grouting to repair modular grade crossing in New Jersey.

Settled modular grade crossing being repaired with polyurethane grouting.

Crossing Use:  

Heavy haul freight (silica mine), urban street by short line 

Problem:

100 track feet of crossing panels settled.  This caused the adjacent asphalt pavement to fail, and caused tripping hazards at the adjacent pedestrian sidewalk.  The crossing ran diagonally across the roadway.  The crossing had been replaced twice in the past.  The last replacement used flowable fill as the base material.  Due to the urban, primarily passenger automobile traffic, there was little deflection of the crossing panels from highway traffic.  However, there were up to four inches of deflection from rail traffic loading.  

The deflection from rail traffic loading caused the top edges of adjacent panels to be in compression with each other.  This caused extensive spalling of the surface, which affected approximately 8 panels.  While not a functional problem for panel integrity, the spalled areas were within the sidewalk portion of the crossings, and therefore posed tripping hazards.

Constraints:

The repair had to allow immediate vehicular traffic to facilitate a single lane closure that was flipped halfway through the repair.  The repair also had to allow for immediate resumption of rail traffic.  The crossing served a sand mine, so repair was designed around high service loads for heavy haul rail traffic.

Due to scheduling constraints of the railroad, the repair method had to tolerate the potential for rail traffic during the repair.  

Solution:

Grouting modular grade crossing with polyurethane foam.

Repairing modular grade crossing using polyurethane foam.

High density polyurethane polyurethane grouting to stabilize and lift the affected modular grade crossing panels.  

Supplemental anchor bolting was also used to ensure longterm integrity of the repair.

Epoxy-augmented patching of the spalled areas to restore a smooth walkway for pedestrians. 

Result:

CJGeo modular grade crossing repair crew filled the voids and corrected settlement in less than a day.  Asphalt patching was done concurrently with polyurethane injection.  The entire repair was completed in less than one day.  The roadway and rail opened up immediately after the repair.  Traffic control was done to accommodate pedestrians and roadway traffic.  

Two trains passed through the crossing over the panels being repaired during the repair.  This did not affect the integrity of the repair.