J01d Geotech Report - UO Pavement.pdf

This Pavement Engineering Report details geotechnical exploration and pavement engineering services for the U&O Health Center project located at 6932 E. 1400 South in Fort Duchesne, Utah. Terracon Consultants conducted 16 test borings across the site to evaluate subsurface conditions and develop pavement design recommendations. The existing pavement consists of asphalt concrete (AC) and portland cement concrete (PCC), estimated to be more than 10 years old, with approximately 65,967 square feet of asphalt concrete pavement and 1,152 square feet of concrete pavement.

The subgrade soils are predominantly silty sand with gravel, classified as SM and SC, with varying densities. Laboratory testing revealed moisture contents ranging from 2.3% to 18.7%, with an average of 9.8%. For the proposed pavement areas, Terracon recommends removing existing asphalt and/or aggregate base course as needed and constructing a new 4½-inch asphalt concrete section over 4 inches of aggregate base course. The pavement design is based on NAPA Traffic Class I for automobile drives and parking areas, with an expected 7,000 Equivalent Single Axle Loads over a 20-year design life. Dynamic Cone Penetrometer testing indicates an average California Bearing Ratio (CBR) of 23 for the subgrade soils.