Pena Boulevard is the main roadway to the very busy Denver international Airport. The road is a four lane divided highway which traffic cannot be interfered with in any way. Pena Boulevard from 2nd Creek to 64th Avenue was a concrete road which had a very severe Alkali-Silica Reactivity (ASR) problem. The road was requiring a lot of maintenance and needed to be replaced. The road was originally built in the early 90’s.
The project had 86,258 SY of 11” dowelled concrete paving. The project crushed the existing concrete in place to 3” minus and placed 3” of Class 6 road base on top of the crushed concrete. After the roadway was paved a 12’ shoulder was added with curb and cable rail to provide better drainage and safety. Trench drain was ran the entire length of the project to provide even better drainage. The airport uses a lot of magnesium chloride so vegetation is hard to maintain. The drainage features minimized the location of mag chloride. After both inbound and outbound were completed the temporary asphalt road in the median was removed. The entire area was top soil and seeded.
Castle Rock Construction utilized an optimized concrete mix on all of these projects. The mix design was a flexural strength mix with portland-limestone cement, 20% Class F fly ash, water reducing admixture, air entraining admixture and four aggregates; #4 coarse aggregate, #7 coarse aggregate, #9 aggregate, and concrete sand. 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. Portland-limestone cement proved to be consistent and helped contribute to the achievement of the quality performance incentives. The 28 day flexural strengths average was 685 PSI. DIA and the Design Team were very happy with the optimized portland-limestone concrete mix design and the ride numbers.
The City and County of Denver and CRCC are very proud of this project and the results. The project is aesthetically pleasing, sustainable and was built with as little inconvenience as possible to the surrounding area and flying public.
Editor's Note: The participants from this project were presented their award at the "Building Successful Public Projects through Innovation, Sustainability, and Leadership Luncheon & Forum" at 2015 World of Concrete. Here are their presenations:
Luncheon & Forum Introduction: Building with portland-limestone cement – Tim Cost P.E., FACI, Holcim (US) Inc.