Denver's new international runway, runway 16L/34L
Russell P. Smith, DMJM Aviation
Robert E. See, DMJM Aviation
Elizabeth Hodgkin, URS
Developing a facility requires a team to manage cost, schedule and achieve quality required by the stakeholders. Runways are an essential component to the safety of the air travelers. Construction standards for runways are one of the most stringent in the United States. Denver's New International Runway project embodies a successful project by managing quality, safety, cost and schedule to meet the goals of Federal Aviation Administration and Denver International Airport.
From the beginning of the airport project in 1987, the FAA considered Denver International Airport (DEN) an integral part of the overall U.S. Transportation Plan because it would be a centralized non-port type facility figuring strongly in the national and International transportation and cargo system. For several years before that, Denver and local businesses had been searching for a solution to the area's transportation shortcomings. Once the airport project was conceived, none of the principals ever looked back.
The plan for the sixth runway project was part of the Master Plan for DEN. Since the original scope was developed 15 years before runway construction began, the final runway design had to be upgraded for the next generation (Group VI) of aircraft equipment currently being developed.
Summary of Project
Runway 16R/34L was constructed according to the Federal Aviation Administration Airplane Design Group VI runway complex specifications. This runway is the sixth runway at Denver International Airport. The runway is 16,000 feet long, 200 feet wide and is 33 percent larger than the other runways at DEN.
The project scope included:
- 890,000 square yards of 12 inches lime-treated sub-grade.
- 890,000 square yards of 8 inches cement-treated base.
- 865,000 square yards of 17 inch full strength concrete paving.
- 428,000 square yards of 10 inch asphalt shoulders.
- 30 miles of edge and under drains.
- 75 miles of electrical conduit serving 4,000 airfield lights and signs.
- 350 electrical and edge and under drain manholes.
Creating a Runway
The FAA essentially initiated the push for Denver's sixth runway. The airport's Planning Management Team needed only to revisit the conceptual plans and proceed with the next step, which was to bring an airfield designer on board. The City's Technical Services Division – which authors project scope for advertising and initiates Requests for Qualifications and Proposals – did its part and the project was set in motion. A number of steps had to be followed, involving presenting the plan to the Mayor and City Council, and receiving the Auditor's approval of funding. The Manager of Aviation performed those tasks. Previously, when Denver airport marketers approached international airlines about serving Denver, they had been hindered by the lack of a runway long enough to serve fully loaded, wide-body aircraft at a mile-high altitude. So, municipal approval of the project was considered a mere formality.
It became obvious that time was critical. Completion of the project on the date projected by the FAA would not allow for the normal progression of fully approved plans prior to the bidding process. Nor could work be held until the plans for construction were finalized. The alternative was Plans in Progress and the City's ability to work directly with the design firm. This excluded the option for a design-build team and made a clear case for the Fast-Track process. The design bid was completed and a contract signed by July 1, 1999. The bid for the grading and drainage phase was scheduled for advertisement that October. The City of Denver requires a 30-day advertisement period followed by a bid conference and then 30 additional days before the bid opening by the Technical Services Division. Once the bids are opened and the qualifying low bidder is determined, there is a one-week period of review to verify the winner. The contract then goes to the City Council. It must pass two votes by the council, be approved by the Auditor's Office and then be signed by the Mayor. The process takes about six weeks, and then the proposal goes to the second owner, the FAA, for its separate review and approval.
While that process was going on, the Project Management Team was coordinating mobilization and startup with the contractor. Even though the City had ratified the contract, it was not fully executed without the FAA's letter of acceptance. Despite a risk of not being paid for work done before the FAA's signature, the contractor proceeded some mobilization and geotechnical work. FAA approval finally came on March 10, 2000, and Notice to Proceed was issued March 19. It was a 284-day contract to move 10 million cubic yards of soil and to blue-top the final runway and taxiway elevations. At the same time the Project Management Team was meeting with the DOR to complete the paving and lighting plans. The final grading design was still not ready to issue for construction and they were hoping to issue second-phase NTP by August. The grading contractor was receiving survey data from the DOR on a daily basis and was barely able to stay ahead of the earthmovers. Finally, on April 23, the grading and drainage plans for construction were published.
The paving and lighting bid packages were ready for advertisement in April. The time sequence described above was the same for this package. The follow-on contractors were chosen and the NTP set for Aug. 13, so the contracts overlapped. The earthwork and drainage work were 120days from completion, and even though one end of the runway was blue-topped and ready for the next phase, the follow-on contractors could not begin work until the FAA gave final acceptance of the work. The FAA agreed to inspect the work in phases so the follow-on work could begin. The Aug. 13 NTP left 730 days to complete the project and have it certified for passenger transportation by the date determined by the FAA. The federal agency became very cooperative in accepting alternatives to its standard process for inspection and acceptance of airport projects. There was no compromise of the standards, just a different perspective in cooperating on a timely basis. The project truly became a management consortium.
The electrical control station (vault) received NTP Jan. 18, 2002. There were now four major contracts in progress simultaneously. The vault was completed on time and on budget, so the airfield lighting could connect and a fifth separate contractor come on board to install the data equipment that operated the airfield lighting. The contractor also had to sequence in the existing five runways. The software was completely re-engineered, so neither the Designer of Record nor the manufacturer knew how it was going to behave. The hi-tech contractor was Israelis, which created an interesting service scenario. Their work came at the very end of the project, and they were not in the CPM schedule so they had to fit their work in as best they could. Eventually we had to schedule a daily meeting at the electrical vault with all contractors to coordinate the hi-tech work. Everyone made concessions and scheduled around them. Without this action they were not going to finish. Sixty days prior to opening, the lighting controls had to be operated manually for the runway certifications. The controls were brought on line, fully automated, with less than a week to opening.
The key to the success of the work and reaching every on-time milestone was the procurement plan. The owners had to weigh the risk and costs inherent with pre-purchasing and stocking materials so they would be available to the contractors as needed. In a world that operates under a JIT supply philosophy, this was a step back in time. But it became the element that allowed the contractors to have confidence in the time criteria. The bulk of the concrete paving process was completed in approximately 120 working days. If we had required the contractor to bring in the materials as needed, there would have been more than 100 aggregate trucks alone coming through the gate each day. That may not seem too great a problem, but one must remember that since 9/11, airport security required that every vehicle entering the facility be stopped and searched. The decision to provide for long-lead purchasing was made in the contract, long before 9/11, but it proved to be one of the more valuable decisions that helped us meet the completion date. At one time there was approximately $9 million worth of stored material on the site, funded through the project. This helped the lower-tiered contractors meet our supply-and-demand situation. During this period, the new runway had the single highest demand for aggregate and cement of any project in the region.
Project Schedule and Risk Management
The concept for Runway 16R/34L was developed during original planning for Denver International Airport (DEN), but the runway was not built because of budget constraints. Soon after DEN opened, the airport continued planning to build Runway 16R/34L. The addition of this runway was seen as an opportunity to open Denver to international travel. To meet the overall project schedule, “Fast-Track” design and construction was employed. Elements of the project were separated into several individual construction projects. The components of the overall project and the companies contracted to perform the work were):
Project Design (CH2MHill)
Grading and Drainage (SEMA Construction)
Xcel Power Distribution Power Grid Enhancement (Managed by Xcel Energy)
Paving and Lighting (Interstate Highway Construction, Inc.)
FAA Runway Instrumentation and Landing Controls (Managed by the FAA directly)
WC Lighting Vault (PCL Construction)
Denver International Airport and the FAA approved the project schedule Nov. 13, 2000, for completion by Sept. 22, 2003. The project was completed and opened for commercial air traffic on Sept. 4, 2003, 18 days ahead of the original schedule.
|Original Date||Actual Date|
First Group VI Runway
Runway 16R/34L is the first Group VI runway in the world. A Group VI runway is designed to handle the next generation of large, long-distance aircraft such as the Airbus A380. Several issues were encountered during the design of the project that required additional analysis and design modifications.
September 11, 2001 (Terrorism)
Because of the terrorist attacks on Sept. 11, 2001, the project was shut down for several days. Access to the project site was impacted by the terrorist attacks. To resolve this issue, new procedures were developed for security, site access and project implementation.
Varying Soil Conditions
Due to the immense size of the project – 200 feet wide and 16,000 feet long for the concrete paving of the runway alone -- the project required several hundred thousand cubic yards of soil. And limited amounts were available which met the project requirements. Extreme efforts were made in quality control and quality assurance to ensure consistent quality of the soil. During the paving section of the project, it was discovered that the soils selected in the previous project would not perform as expected when the first phase, the lime stabilization, was attempted. A critical meeting was held with local experts on lime stabilization to resolve this issue. The findings were reviewed and new procedures were developed for lime and cement stabilization to meet the project performance requirements. These new procedures increased the contractor's production rate, allowing the project to get back on schedule.
The FAA provided a major portion of funding for the project. Due to the Sept. 11, 2001 terrorist attacks, the FAA was unable to provide funding as planned during the summer of 2002. The Project Management Team determined that if portions of the project were slowed (i.e. concrete paving for the runway, which was rapidly expending the budget), the remaining budget could be made available to cover other critical work. The funding agreement with the FAA was restructured, and Denver International Airport secured alternate temporary financing over the winter shutdown.
Revised Fight Checks
As part of the certification of Runway 16R/34L, the FAA performed flight checks with a small aircraft equipped with advanced instrumentation to verify the runway control system. It was unclear if the system would function as designed because this was the first Group VI runway and it was 4,000 feet longer than any other runway that the FAA had ever provided a landing control system for. Sixty days before completion of the runway, the FAA requested that the flight checks be advanced to 30 days before project completion. This was 30 days sooner than the contractor had scheduled, and meant that completion of the runway had to be accelerated. To accomplish this schedule, critical activities had to be identified and the contractor was directed to complete those tasks before the flight checks. The contractor in turn had to redirect personnel and expend overtime to finish the work in time.
Weather is the most detrimental act of God to a construction project. To minimize the potential impact, additional time was scheduled at the end of the project, before the official opening. On March 15, 2003, a heavy snowstorm dropped 36 to 60 inches of snow on Denver and the Front Range, forcing work to stop for several days and absorbing some of this additional time.
Design Error and Omissions – Design is critical to a successful project. When items are incorrectly designed or omitted from plans they quickly become apparent during construction. The Project Management Team encountered several of these issues and addressed each with positive, proactive management.
Safety – Safety is important in high-risk activities such as construction. Managing safety is managing risk at its most fundamental level. The Project Management Team demanded that safety be the top priority of everyone on the job. Contractors held weekly safety meetings, and inspectors were tasked to assure that safety procedures were followed. We can proudly say that there were no lost-time accidents on this project.
Contractor Claims – Contractors find that they may have to perform work which they feel is outside their scope of work, or have to do work differently than they had planned when bidding the project. The result is a claim for additional money and/or additional time. To mitigate claims, the Project Management Team was very proactive in working with contractors as a team member to resolve each issue before it became a claim.
Project Cost Management
The project cost was well conceived for a project that had limited design and planning opportunities. The estimators developed a Unit Pricing System that was applicable to the prescribed work, and for the most part it represented costs the bidders could work with. There was a wide disparity between the bids for this work, but the winner was able to complete the work per the scope and to be profitable. The Project Management Team approved some additional work that primarily covered errors and omissions of the plans. Errors and omissions are an inherent risk when the design and planning phases are fast-tracked. In the end, there was a 2 percent cost overrun, which is very low for a project this size managed in this manner.
Original Budget: $166 million was budgeted for the entire scope. The budget included design, design services –designer of record, insurance, service contracts for construction management and quality assurance, grading, drainage, paving and lighting, plus construction of an electronics control station and an Airport Rescue and Fire Fighting (ARFF) station. Actual Cost: $154 million all-inclusive.
Project Human Resource Management
The Project Management Team developed as the complexity of the project grew. The initial Project Management Team consisted of the primary stakeholders, airport planners and engineers who guided the project through the first two years. During the second year of the project, senior airport management determined that the complexity and size of the project were outstripping the internal capacity of their organization. At that point, airport management established an independent Project Management Team headed by DMJM Aviation, which incorporated the existing airport staff. To establish clear lines of communication between the Project Management Team and the paving contractor, an organizational chart was developed to show the responsibilities and duties of each team member.
The Project Management Team was developed by identifying the roles and responsibilities necessary to complete the project. Once the roles were identified, the Project Management Team was formed to take advantage of each individual's key knowledge base. Each person was assigned to manage the key task for which they were best suited. (Exhibit 1)
Project Quality Management
Because of the size and complexity of this project, it was agreed that the owners' Quality Assurance and the contractors' Quality Control would be a cooperative effort.
The City and County of Denver contracted with Aguirre Engineers, Inc. to test all soils, lime-treated subgrade, cement-treated base course, concrete and asphalt as required by the specifications. For materials manufactured offsite, such as reinforced concrete pipe, manufacturers were required to certify that the items met or exceeded all the requirements of the specifications.
Aguirre Engineers, Inc. was the Quality Assurance testing laboratory contracted by the City and County of Denver and DEN. As such, they performed all testing on the project. Independent professional organizations were contracted by the City and County of Denver, DEN, to formulate CCD's Quality Acceptance Plan based on the specifications of the project.
The Contractor's Quality Control contractor was AG Wassenaar, Inc. which had Geocal, Inc. as a subcontractor. All asphalt testing was performed by Ground Engineering Consultants. The purpose of the contractors' Quality Control (QC) program was to review the contractors' material testing and installation procedures on a system-wide basis. This review also included performing material tests on a periodic basis and correlating the tests with QA personnel to compare procedures and results.
Both the QC and QA contractors set up field laboratories to handle the quantity of testing that was required. Test results from both QC and QA were provided verbally to the CCD Project Manager's inspector on the site as they were obtained. Written copies of daily test results were compiled and submitted to the quality assurance coordinator on a regular basis, generally within 24 hours.
The FAA required that all failing tests had to be remediated. When an item failed a test – whether it was performed by Quality Assurance or Quality Control – all Project Team inspectors and contractors' foremen were notified immediately. Handwritten test results from the quality assurance testers were submitted within 24 hours to the quality assurance coordinator and the contractors' quality control manager. Every effort was made to resolve failing tests once they were found in order to avoid delays or questions regarding the remediation of that test.
A Construction Management Report was compiled and submitted to the FAA. This report included the Designer of Record's qualifications, the owners' Quality Assurance Plan and personnel, Contractors' Quality Control Plan and personnel, the owners' and the contractor' Inspection procedures and frequency of testing, daily and test result reporting, submittal process, and the Final Construction Report for the FAA.
A 3,000-square-foot “Beam Facility” was constructed on site to test the concrete pavement, using funds from both the City and contractors. This facility was constructed in an effort to ensure consistency and eliminate any questions concerning test results. The concrete was sampled, tested, molded and cured, and the beams were then broken (see flexural strength machine at left) utilizing both QA and QC personnel. The sharing benefited both parties by reducing costs and management resources.
The sampling frequency for Structural Concrete was in accordance with ASTM C-172 and the compressive strength tested in accordance with ASTM C-31, ASTM C-39. The Specification Section for P-610 did not specify the structural concrete-testing frequency, so we required a minimum of one test per day for each mix design. Normally the contractor placed under 50 cubic yards each day. For each sample, QA prepared a set of cylinders and performed slump and air entrainment tests.
Approximately 890,000 square yards of lime-treated subgrade were processed. Acceptance tests were taken every 1,500 square yards as required for moisture and density, thickness and pH; tests were taken every 6,000 square yards for Atterbergs and compressive strength.
The subcontractor performing the lime treatment ensured that there were no failing subgrade tests, and all proof rolling was completed before the lime treatment began. The lime treatment was completed in two phases -- initial mixing and final mixing.
When initial mixing began, the subgrade was trimmed and all excess material was disposed of. Lime was spread only in areas where the mixing operations could be completed during the same day. Lime content was based upon spread rate; a minimum of two passes were performed with the mixing machine and the mixture was not left exposed for more than four hours. The moisture content during mixing was kept at 3 percent of optimum or above, and was maintained at optimum moisture or above for the duration of mellowing.
Final mixing began after a seven-day curing period. The moisture at the start of compaction was 0 percent to 3 percent above the optimum moisture content. One moisture/density test was taken for every 1,500-square-yard sublot with a minimum density requirement of 98 percent.
Compressive strength pucks were taken and tested, and a minimum strength of 200psi after five days was required. If the material did not reach the strength, the area was treated with cement to increase the compressive strength. Areas that had been treated at the end of 2001 were left one inch high as a form of protection over the winter, and the overage was trimmed off in the spring.
Approximately 890,000 square yards of cement-treated base were placed. Acceptance tests were taken every 1,200 square yards as required for density, compressive strength and thickness.
Prior to placement of the cement-treated base course, all ruts and soft areas were corrected and the subgrade was moistened. Initial moisture at the start of compaction was between 0 percent and 2 percent of optimum. After compaction the cement-treated base course was kept moist until the final bituminous curing coat was applied at a rate of 0.1 to 0.25 gallons per square yard. The area was then protected for seven days. One moisture/density test was taken for every 300-square-yard sublot, with a minimum density requirement of 98 percent. The seven-day compressive strength cores were taken for every 1,200-square-yard lot. The specifications required a minimum strength of 750psi and a maximum of 1,200psi. One thickness test was taken for every 300-square-yard sublot.
The measure of a successful project is based on the satisfaction of the owner. Denver International Airport's goals were to open Runway 16R/34L on time, within budget and meeting the quality standards required by the Federal Aviation Administration. All of these goals were meet through the efforts of the Designer of Record, Project Management Team, construction contractors and support from upper management of the airport.
©2004, Brooks B. Allshouse, PE
Originally published as part of 2004 PMI Global Congress Proceedings - Anaheim, California