Urban Grade Crossing, Cumberland, NJ

Urban modular grade crossing repair–Cumberland, New Jersey

Polyurethane grouting to repair a settled modular grade crossing.

Polyurethane grouting to repair a modular grade crossing.

Crossing Use:  

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

Problem:

32 track feet of crossing panels settled.  This caused the adjacent asphalt pavement to fail, and caused tripping hazards at the adjacent pedestrian sidewalk.  The grading in the area was relatively good, however the adjacent ballast was fouled, which caused water to accumulate under the crossing panels and wash out the sandy subbase material.  The crossing had been replaced recently.  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 two of the 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.  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:

Modular grade crossing repair using polyurethane grouting, epoxy concrete patching, and asphalt repair.

Polyurethane grouting, asphalt patching and panel patching.

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 two hours. 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.