Airport Improvement Project
Challenge & Solution
A West Virginia airport proposed an improved Runway Safety Area for one of its runways. The current safety area is 400 feet wide and 250 feet long. It is being extended 750 feet to meet Federal Aviation Administration (FAA) requirements and to create a safety area that is 400 feet wide and 1,000 feet long.
This expansion will require approximately 250,000 cubic yards of structural fill borrow for the proposed embankment. The borrow site was thought to be the location of a strip-mining operation.
Project Description & Highlights
Rhea served as the subcontractor for the geotechnical investigation on this project. A review of an in-house soils survey, geotechnical, geologic, and mining literature of the project area as well as plans, reports, and additional literature of the site was completed prior to field reconnaissance. The field work involved evaluating the condition of existing pavements, the proximity of existing structures, site drainage, evidence of groundwater, exposed mine spoils, fill, soil and rock, evidence of mine subsidence, and/ or other site conditions that could affect the proposed construction.
Rhea finalized the client’s Subsurface Exploration and Testing Program (SE&TP) based on the results of the review and field reconnaissance. The SE&TP consisted of 20 test borings totaling approximately 536 linear feet of drilling. Rhea provided a full-time boring inspector during drilling, who logged the test borings, observed that drilling was performed in accordance with specifications, and coordinated with airport personnel. Rhea also provided a part-time drilling inspection supervisor to oversee the drilling program and to modify the drilling program to reflect subsurface conditions encountered.
Rhea performed laboratory testing on soil samples to determine physical properties. The analyses evaluated potential impacts of the site subsurface conditions encountered on the proposed construction. Also, a Test Boring Location Plan, Engineers Field Boring Logs, geotechnical cross sections, and a Geotechnical Investigation Report were prepared.
Rhea’s in-depth understanding of our region’s potential geotechnical problem areas – for this project, the presence of colluvial soil beneath the planned embankment – led to experienced based slope stability analyses and recommendations including 2H:1V slopes, 10-foot wide toe benches, and six-foot wide bonding benches for stability.