I-76 Brush Reconstruction

The I -76 Project in Brush Colorado was a multi-faceted endeavor requiring a diverse group of contractors. It was built for the Colorado Department of Transportation in conjunction with the City of Brush and Morgan County. Atkins Global and Rocksol engineering were partners on the job providing construction management for CDOT. The project involved:

• 500,000 CY of embankment material imported to the project by CRCC
• Drainage and underground utility improvements were installed by CRCC pipe crews to facilitate the new roadway configurations.
• 306,500 SY of doweled 10” and 12” concrete paving were placed by CRCC.
• Existing concrete and asphalt pavements were removed and crushed into recycled Class 6 road base by CRCC utilizing our closed circuit impact crushing plant.
• 13 bridges, generally over existing county roads crossing I76, were demolished by subcontractor Penhall Company and rebuilt by subcontractor Jalisco International. The new bridges are 3 to 5 feet higher than the existing structures were to accommodate agriculture movement from one side of the freeway to the other.
• 43,000 SF of decorative and structural block wall built by Max Retaining Walls allowing for better drainage and wider clear zone beneath the bridges at the county roads.
• CRCC mined and produced fine and coarse aggregates for concrete paving utilizing our aggregate crushing, screening and washing equipment.

To aid in our continual quest to improve the quality of our concrete paving, Castle Rock Construction designed an optimized concrete mix for this project. The goal of this design was to produce a consistent mix which could maintain a Coarseness Factor (CF) of 60 and a Workability Factor (WF) of 35 in a modified Shilstone Graph. This was accomplished with the use of a four bin feeder and pug mill being added to the concrete batch plant. The purpose of this proportioning and mixing was to aid in the production of a more consistent concrete batch and a better platform for the concrete paver with the ultimate goal of producing a smoother ride on the concrete paving. The optimized mix is a positive factor in the production of smoother and more durable concrete pavements. The end result was a very consistent concrete being produced and very good rides on this project. The design specifications were attained on this project for strength, depth and ride.

Castle Rock Construction is very conscious of sustainability and the environment. All of the old concrete and asphalt will be reused as road base or concrete rock. CRCC uses cement from Holcim US which has ground up limestone to replace a portion of the cement which in turn reduces our carbon footprint. Also, we use fly ash in our concrete which is a waste product from power plants.

This project is a shining example of a concrete road that provides a smooth ride and a good investment for the people of northeastern Colorado for 40 years to come.