Prosper ISD’s new Walnut Grove High School campus, built in an accelerated two-year time frame, sits on an 85-acre site with an overall relief of more than 50 feet.  Considerable cuts and fills, necessary to accommodate the site’s elevation changes, presented different challenges and surprising benefits for subgrade preparation.

Due to the sloping nature of the site, excavation exposed weathered limestone on some of the school’s pavement areas.  Geotex recommended capitalizing on the non-expansive subsurface materials by eliminating an expensive lime stabilization process and place pavements directly on the compacted weathered limestone bedrock.  However, The Town of Prosper’s engineering standards for fire lane pavements mandated lime stabilization, which is typically used on fills and soils to “strengthen” the subgrade.  After a review of substantiating data from Geotex’s Dynamic Cone Penetrating (DCP) testing program, the Town of Prosper allowed fire lane pavements be placed directly on the compacted weathered limestone in those areas.  Eliminating the lime stabilization treatment saved Prosper ISD considerable time and money on paving.

A DCP test is used to determine the strength and stiffness of the subsurface materials. Geotex engineers are able to estimate the load bearing capacity the soil can withstand by measuring the calibrated cone’s penetration into the ground. Check out other K-12 projects on our Education page.  

Prosper ISD Walnut Grove High School