I-70 Design-Build Near Agate, CO

Project Focus
The Agate project is a $20.6 million, 11.4 mile “whitetopping” of I-70 east of Denver. This was the fourth of a series of CDOT limited scope Design-Build projects. CDOT, in cooperation with the Colorado contracting and engineering communities, developed the delivery system with the specific objective of providing the public with early tangible results for surplus legislative funds dedicated to transportation.

Teamwork was critical to the success of this project. The Contractor, Designer, Owner and all subcontractors recognized that the Design-Build, lump sum method of contracting required extra care in communication and partnering. All stakeholders from the pre-construction partnering session and throughout the project were cooperative, quickly resolving disputes to the benefit of the project.

Project Details
Schedule & Complexity
The project was bid in April 1998, and the design fast-tracked so that construction on the first half could be completed fall of 1998. The pre-construction partnering session organized and implemented a unique, continuing formal communication process to reflect the special needs of a Design Build project, which requires that Owner, Contractor and Designer personnel adopt roles much different from those on traditional projects. The partners agreed that for the project to succeed the design would not be fully complete prior to the start of construction activities. The partnering process required the formation of a "Design Leadership Team" (DLT) to facilitate the rapid development of final design and ensure that the design schedule of work, review, dispute resolution and approval did not delay construction of the project.

Construction & Innovation
This project was the first to allow the contractor to select a compressive or flexural method for basis of acceptance. Historically the CDOT specification has accepted PCCP on the basis of compressive strength, specifying a high 677-pound per cubic yard cement factor, to ensure meeting design flexural strengths. The industry worked closely with CDOT to develop this pilot specification, which allowed reduction of the cement factor to 600 pounds only if the Contractor agreed to flexural acceptance. With careful control and blending of aggregates, the Contractor was able to achieve strength incentives and save the CDOT significant cost in cement.

Contractor Quality Control (CQC) tests determined acceptance. CDOT recognized an opportunity for improvement by eliminating the duplication of QC/QA tests that two qualified labs performed. They developed a CDOT specification, in cooperation with the industry, in which CDOT ran independent F&T tests to provide oversight and statistical verification. This major cost benefit was achieved only through the cooperative partnering efforts of CDOT, FHWA and the industry. This CQC/Acceptance with QA verification is now a model for other similar projects and will improve productivity, and save significant dollars on all future projects where adopted.

Quality
The project exceeded all quality standards and the DB contractor received quality incentives of $322,298 for strength, thickness and smoothness, all which will be returned with interest to the public in the performance and serviceability of the pavement.