Valley Forge Laboratories, Inc.

Location:   Interstate 80, Mercer County, PA

Client:   Pennsylvania Department of Transportation

Description:
This research project, sponsored by PennDot and FHWA, arose out of concern over pre-mature, mid-slab cracking of four year old, reinforced concrete pavement along I-80 in Mercer County, PA. VFL’s forensic analysis and special testing focused on:

• Subsurface drainage
• Materials conformance and crack data

VFL conducted a field inspection of the failed slabs and witnessed the lifting of a cracked slab. Exhumed samples of OGS, 2A and the drainage geotextile were tested in the laboratory for conformance to PennDot standards. The geotextile was also checked for compatibility and long term clogging in order to make an evaluation of the effectiveness of the edge drain.

In addition to analyzing the subsurface drainage, VFL reviewed available data from FWD readings, materials testing, bearing tests and core borings in order to comment on potential causes and mechanisms of the slab failure.

The findings were contained in a final research report.