Green Circle Trail
The Winchester, VA Green Circle project, when fully constructed, will connect areas of historic, recreational, educational, and natural interest, while providing safe facilities and accommodations for both bicyclists and pedestrians. Where possible the circle follows local streams, emphasizing the restoration, protection and interpretation of natural resources and urban green spaces.
The Project is located entirely within the incorporated boundary of the City of Winchester in Frederick County, Virginia and included an 8-foot-wide asphalt surface trail, a prefabricated bridge crossing Town Run and cast-in-place retaining walls. Americans with Disabilities Act (ADA) access is maintained throughout the entire project.
Challenges and Solutions
During the field exploration, very loose marl (alluvial soils) underlain by soft residual soils were encountered at and below the planned pedestrian bridge abutments. The wet and very loose marl extended to approximately 8.5 feet and 46 feet below existing grades. The initial bridge abutments were to be founded on shallow spread footings bearing on residual soils or rock. However, the existing conditions required a redesign of the bridge foundations. Triad worked closely with the architect and structural engineer of record and determined that driven piles would be the most economical solution for the new bridge.
During a later phase of the trail project, the trail was designed to cross along a steep hillside with massive rock outcrops which prevented access for conventional drilling and testing. In order to evaluate conditions along a planned retaining wall in this section, Triad performed rock coring with a Milwaukee core machine equipped with a 4-inch diamond impregnated core bit to collect rock samples for compressive strength testing. This unconventional approach provided the information required by the structural engineer to complete final wall designs and kept the project moving forward within budget.Services Provided: