Open-end Geotechnical Services: Pennsylvania Turnpike Commission

In one contract, GeoStructures utilizes finite element method (FEM) analysis to model distressed pavement joints between concrete slabs, and to investigate the effects of mesh reinforcement on rehabilitation. Specifically studied are the contribution factors of pavement joint deterioration due to loss of support, aggregate interlock and dowel bars, as well as the effectiveness of steel mesh reinforcement in retarding reflective cracking through an asphalt overlay.

In another contract, GeoStructures implements a pilot program to evaluate all aspects of lime and cement stabilization construction, such as hydration, mixing, mellowing, stabilization depth and uniformity, and compaction including roller specifications. Forensic studies compare the effects of frost heave for stabilized and non-stabilized soils.

In a third contract, GeoStructures performs air void analysis in accordance with PennDOT PTM 623, “Method of Test for Air Content of Hardened Concrete” and ASTM C457, “Standard Test Method for Microscopical Determination of Parameters of the Air-Void System in Hardened Concrete” (modified point count method). Calculated parameters include total air void content, specific surface, spacing factor, void frequency, paste-air ratio, and the relative percentages of cement paste, aggregate, and air voids.