First reaction

Colorado project embraces new approach

Asphalt Paving Article July 05, 2017
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Unforeseen subgrade conditions, work-hour and construction-zone restrictions, heavy truck traffic and working in part of a floodplain—all these issues were encountered during the reconstruction of 30 miles of U.S. Rte. 85 (Ault to Wyoming) in northern Colorado.

 

Each of the issues had the potential to individually create problems for the project; coupled together, they had the power to bring the project to a standstill. In response, the team kicked off this $19 million job by strengthening their partnering relationship and embraced a “project-first” approach to deliver a quality project on time and on budget.

 

Back after all these years

Starting in 2015, the Colorado Department of Transportation (CDOT) began making safety improvements to a 30-mile span of Rte. 85 between the town of Ault and the Wyoming state line in northern Colorado. Work began just north of Rockport at mile marker (MM) 309.5 and moved south through several communities to MM 281 just south of Ault in Weld County. Throughout the scope of the project, the towns of Ault, Pierce, Nunn, Carr and Rockport were impacted either directly or indirectly. The scope of the improvements included the addition of shoulders to sections of the highway, installation of rumble strips along the centerline of the roadway, repaving of the highway, realignment of a portion of the highway just north of Ault, irrigation and drainage improvements, bridgework, the installation of new snow gates north of Ault and at County Road (CR) 100 in Nunn, and the installation of a new weather station at CR 100 in Nunn. The project was partially funded through FASTER (Funding Advancements for Surface Transportation and Economic Recovery) funds, which are dedicated to projects that will improve safety or replace structurally deficient bridges. 

 

Not only did the project create a smoother ride for motorists, but sight distances were improved thanks to the addition of shoulders to the highway as well as the highway realignment. The addition of rumble strips along the centerline helped enhance the safety of the highway. Drainage improvements helped accommodate the flood flows of nearby water sources, and the installation of the new snow gates will allow CDOT crews to safely close the highway during the winter when inclement weather is present.

 

Not much work had been done to this section of Colorado highway over the last 20 years and the existing asphalt was in poor condition. Additionally, the highway carries 17% truck traffic (agricultural and oil and gas), compounding the problem. CDOT Region 4 evaluated rehabilitation alternatives and elected full-depth reclamation (FDR), and the in-house design was completed by CDOT designer Eric Salemi.

 

CDOT project manager Nicki Upright commented that, “Eric did a great job with the plans and was available during construction to answer questions and offer guidance. There were only minor changes needed during construction.”

 

Near 100

CDOT awarded the contract in February 2015 to Connell Resources Inc. of Fort Collins at a bid of $19.1 million. The 260-working-day contract included a 10% DBE goal and was split into two phases to occur during the 2015 and 2016 construction seasons. The overall scope of the project included reconstruction of 29.2 miles of Rte. 85 (from Ault to the Wyoming state line) with FDR of the existing asphalt; new hot-mix asphalt (HMA); an aggregate base course; embankment; structure rehabilitation; culverts; seeding; erosion control; fencing; signing; striping; rumble strips; installation of a weather station; and road closure gates. Project bid items included 460,000 sq yd of FDR (up to 16 in.) and placement of 151,000 tons of new HMA.

 

Paving was performed in two lifts with the bottom lift consisting of 90,000 tons of S75 (PG 64-22) with a 5.3% binder, and the top lift comprised of 61,000 tons of SX75 (PG 64-28) with a 5.6% binder. Neither of the mixes included recycled asphalt. During construction, Connell Resources did an excellent job of responding to any out-of-spec material samples and correcting issues. Quality levels were near 100 in most areas, and for the top mat Connell earned 100% of the available incentive.

 

First of many

In May 2016, CDOT’s Division of Project Support engaged in a new era of partnering, which was themed “Project First.” The renewed program was supported by the chief engineer and rolled out to each of the regions across the state for implementation. At the agency level, as well as the project level, CDOT focused on working to improve how partnering could better serve its transportation projects. In doing so, it developed the following partnering mission statement: “CDOT and the Colorado Contractor’s Association are committed to advancing a culture of collaboration that focuses on ‘project-first’ solutions wherever possible. This will be achieved through a partnering strategy designed to foster mutual professional trust.” 

 

The strategy consists of three prongs:

  • Partnering Training
    • Mutual understanding will build trust and promote empathy (both sides look for opportunities to help partner).
  • Partnering on Projects
    • Executive partnering (executives committed to participating and stepping in if the project goes off track);
    • Vertical partnering (mitigating risk for field personnel and consultants to make reasonable decisions); and
    • Horizontal partnering (solving problems at the project level, escalating in a timely manner as needed).
  • Partnering Tools
    • Constructability reviews;
    • Flexible start dates as appropriate;
    • Develop escalation matrix (clearly define roles and responsibilities for CDOT, prime and consultants);
    • Collaborate with utility owners to minimize delay claims; and
    • Capture lessons learned at the end of projects.

 

Crews, here laying down the surface mat on Rte. 85, worked adjacent to a floodplain.

 

Project First in action

Prior to starting the FDR of the existing asphalt (performed by ARS of Littleton, Colo.), Connell engaged King Surveyors out of Windsor to survey the northern portion of the project. The cross slope of the existing highway was reviewed by the project team, and a plan was formulated on how best to re-establish the 2% cross slope during the FDR process. To accomplish this, a GPS model was developed and followed during earthwork performed by Connell after the FDR had been completed. A scraper was used to pick up the excess material and stockpile it for later use and the grade was verified in front and behind the paver with a straight edge. 

 

“Using the process allowed us to achieve what we needed to do and successfully balance the FDR material,” stated Upright.

 

During construction, Connell was allowed a maximum of three 2-mile lane closures at any time with a minimum of 1-mile separation between closures. The work-zone restrictions enforced by CDOT created challenges at times for the contractor to move equipment and labor from one worksite to another, including trucks delivering HMA to the paving operations.

 

CDOT mandated and strictly enforced 10-hour workdays for the duration of the project. Because of this limitation, Connell found ways to put the project first and work with its subcontractors to help reduce delays in the work, thereby maximizing overall daily productivity. For example, Connell established all of the points for striping using GPS, then when the stripers arrived, the subcontractor was able to quickly pull its string line and start work, allowing more time for paving.

 

Connell maximized its paving time so that the project averaged approximately 1,800 tons per day during the 2015 season and approximately 1,400 tons per day during the 2016 season. During the winter shutdown between Phases I & II, Connell reviewed smoothness and QPM data to establish ways to improve quality in 2016 during the Phase II portion of the project. 

 

When asked about achieving overall quality on the project and what elements CDOT was looking for, Upright stated, “When CDOT is evaluating quality on a project like this, we’re looking for consistency in the HMA being delivered to the project from the plant. We’re also looking at the smoothness of the completed roadway. If the contractor is meeting both of these goals, we’re going to get a quality product that will be serviceable for a long time.”

 

Ed Wells, asphalt manager for Connell Resources, addressed their perspective as the prime contractor on delivering quality, stating, “When it comes to Project First and overall quality, Connell focused on making sure the bottom layer of asphalt was smooth, which then allowed us to place the final lift to meet and even exceed final smoothness requirements.”

 

Trouble below

During the Phase II portion of the project (2016 season) the largest challenge to the project team was soft subgrade. As soon as construction began in the spring, the rains came. Placing aggregate base course material as part of the shoulder widening provided significant challenges due to moisture retained in the base. The town of Pierce also provided unique challenges to the team due to its location in a floodplain. Additionally, in Pierce, the team found a layer of problematic gray clay that had to be mitigated along with a sinkhole and unknown subsurface pipes that had never been used. 

 

Overall, the project was a success due to the Project First team mentality from CDOT, Connell Resources, the subcontractors and consultants. Numerous CDOT, contractor and consultant trainees were placed on this project, gleaning valuable lessons in partnering and construction of a successful project. The project team was glad to assist in the training to help improve the on-site knowledge of personnel for the future of the industry. 

 

The best there is

Every year the Colorado Asphalt Pavement Association (CAPA) hosts its annual “Best in Colorado” paving awards program, a capstone program to recognize superior projects completed that year. In 2016, 69 individual projects were submitted from across Colorado for judging and consideration in 12 different categories. Based on the quality of construction for the Rte. 85 project, the project was submitted in the Rural Highway Reconstruction category by the CDOT project manager. Projects are judged on six different categories, including:

  • Overall appearance;
  • Segregation;
  • Longitudinal joints;
  • Transverse joints;
  • Ride quality; and
  • Project size, difficulty and complexity.

 

After the judges inspected the site, scores were tabulated and the project received 331 of a maximum 350 points, winning the Rural Highway Reconstruction category. Additionally, the 331 points awarded for this project made it the highest scoring project in the history of CAPA’s 23-year award program. The judges awarded a perfect score in three categories (Segregation, Longitudinal Joints and Ride Quality) and provided the following comments: “Very, very smooth ride. There were a few must-grind spots, but they were nicely done. The longitudinal joints were barely visible, the transverse joints were visible but super smooth. Awesome project.”

 

With all project team members embracing the Project First approach, all worked to keep everyone informed on what was happening and when. Shared information allowed everyone to work in the most efficient manner while doing their best to maximize quality, reduce risks, control costs and minimize impacts . . . after all, that’s putting the project first.

 

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Wells is the asphalt manager for Connell Resources. Upright is a project manager for the Colorado DOT Region 4, Greeley, Colo. Pacholek is the paving foreman for Connell Resources. Anderson is an estimator with Connell Resources. Skinner is the director of pavement engineering with the Colorado Asphalt Pavement Association.

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