InnovoGeo Engineering completed a preliminary geotechnical engineering investigation and report for a proposed multi-building development project in Henrico County, Virginia.  The project site included existing development, previously graded areas, wooded portions, and variable Piedmont subsurface conditions.

InnovoGeo’s field investigation included private utility locating and limited clearing of vegetation through wooded and tall grass areas for rig access.  Subsurface conditions were evaluated across the proposed development area through twenty-four CPTu soundings, which were supplemented with Dynamic Probing Super Heavy (DPSH) testing at four select locations encountering shallow CPTu refusal.  The investigation was performed using InnovoGeo’s limited-access tracked CPT/DPSH equipment, allowing efficient collection of continuous subsurface data across a variable site.

The preliminary geotechnical report included interpretations of subsurface stratigraphy, groundwater observations, preliminary recommendations for foundations, pavements, earthwork, difficult excavation considerations, and guidance for final design-level investigation.  Key geotechnical considerations included variable depth to refusal, weathered Piedmont rock conditions, localized near-surface high-strength materials, possible previously modified soils, and softer clay zones that may influence settlement-sensitive design.  InnovoGeo provided practical recommendations to support early planning, budgeting, and coordination with the project design team.

Near-surface high-strength materials encountered in portions of the site exhibited CPTu cone tip resistances ranging from approximately 200 to 500 tsf over intervals several feet thick.  Although these conditions could easily have been misinterpreted as shallow weathered rock, InnovoGeo recognized from the surrounding subsurface data and local geologic experience that additional investigation effort was warranted.  Despite the challenging anchoring conditions encountered by our Pagani rig, strategic offsets and increased field investigation measures enabled the collection of valuable subsurface data through and below these materials, providing the project team with a more complete understanding of the subsurface conditions and their potential implications for design and construction.