LACO performed a geotechnical exploration in support of the design and reconstruction of an existing, severely distressed, pedestrian/bicycle path along Copeland Creek in Rohnert Park, California. The path consists of discontinuous segments, totaling approximately 4,750 lineal feet. The path is predominantly underlain by highly-expansive adobe clay soils which shrink and swell, and move laterally (especially where unsupported adjacent to the creek bank), due to volume change during seasonal moisture gain and loss.
The primary purposes of this investigation were to explore and characterize subsurface soil conditions at the site and to develop geotechnical recommendations and construction cost estimates for path reconstruction. Our project team performed the following services as a part of this project:
- Field exploration and sampling, including six exploratory test borings
- Laboratory testing
- Analysis of path reconstruction options and associated costs
Results from the exploration and laboratory analysis were used to provide the design team with recommendations for subgrade preparation to address the detrimental expansive adobe clay soils; fill placement; and surface and subsurface drainage control; and to provide construction cost estimates for eight different reconstruction alternatives.