Digital Technologies and Innovative Contracting Improve Caltrans Bridge Project Outcomes
With unified data and connected workflows, a DOT and a construction firm fast-track productivity and pave the way for efficient asset lifecycle management.
By Adrien Patanè
As historic funding levels drive up the volume of infrastructure projects in the U.S., some state departments of transportation (DOTs) are increasingly struggling to deliver projects as planned. As if labor shortages and rising costs were not enough of a challenge, most transportation agencies are also contending with a legacy of outdated technologies, siloed data that makes information difficult to access or share, and disjointed workflows that hamper collaboration, thereby causing schedule delays.
To address these issues, innovative DOTs and their business partners are adopting digital technologies and new collaboration methods to increase access to siloed data and streamline workflows so projects can finish on time and within budget.
With the support of policy organizations such as ARTBA’s Innovation and Technology Forum (ITF)—which advocates for accelerating the use of digital technologies in the U.S. transportation construction industry—infrastructure owners, contractors and engineering firms are recognizing the benefits of digital transformation to improve productivity and, in turn, rebuild public confidence in infrastructure projects.
“Digital technologies drive more efficient processes that enable stakeholders to collaborate in ways that promote data visibility and transparency,” said Cyndee Hoagland, cochair of ARTBA’s ITF and senior vice president of the owner and public sector at Trimble. “These technology-enabled collaboration methods not only reduce friction between teams, helping them deliver higher-quality projects with less risk and lower asset ownership costs, but they also allow infrastructure owners to better manage and maintain their assets throughout the asset lifecycle.”
“Digital technologies drive more efficient processes that enable stakeholders to collaborate in ways that promote data visibility and transparency.”
—Cyndee Hoagland, Senior Vice President, Owner & Public Sector, Trimble
CMGC Approach Boosts Collaboration
Caltrans—California’s Department of Transportation—is a recognized leader among organizations adopting innovative collaboration processes and technologies to fuel better project outcomes. As an ARTBA member, Caltrans works with other member organizations, such as Granite Construction, to implement these innovations while delivering new road and bridge projects.
A recently completed Caltrans bridge and highway project highlights the benefits of a collaborative contract arrangement and several digital technologies that yielded positive results for both the DOT and Granite, its construction partner for the project. The $158 million Cosumnes Bridge Replacement Project took place in a high-traffic section of State Route (SR) 99 in Sacramento County.
The project addressed the structural and seismic deficiencies of the aging Cosumnes River, Cosumnes River Overflow, and McConnell bridges by replacing them with three modern bridge spans. Better lighting, wider shoulders, flood abatement drainage and realigned ramps improved safety and mitigated freight mobility issues on these structures that accommodate 70,000 daily vehicle trips.
“Because we completed the project one year ahead of schedule, the public benefited from a safer transportation corridor with less disruption.”
—Aaron Chamberlin, Senior Transportation Engineer, Caltrans
To proceed with this high-profile project, Caltrans entered into a Construction Manager/General Contractor (CMGC) arrangement with Granite. The CMGC alternative contract mechanism facilitates critical communication between the designer/owner and contractor for contractual deliverables. The contractor acts as the consultant during the design process and offers constructability and pricing feedback on design options. By the time bids are requested, the designs have been validated by both the contractor and the designer/ owner, ensuring better bids and more accurate estimates.
“This contract vehicle was a new way for Caltrans to collaborate and share full design files with the contractor early in the design process, which led to improved project staging,” said Aaron Chamberlin, a Caltrans senior transportation engineer. “The results were significant cost and time savings. Also, because we completed the project one year ahead of schedule, the public benefited from a safer transportation corridor with less disruption.”
Digital Technologies Enhance Project Delivery—and Long-Term Asset Maintenance
For the Cosumnes River Bridge Project, Caltrans and Granite used advanced digital technologies to transform traditional workflows and coordinate multiple teams. They used 2D and 3D models to analyze and reconcile conflicts between the design and existing conditions, such as proximity of the bridge work to the active roadway or voids in earthwork design.
“We saved time and money and reduced risk by optimizing the crane placement prior to bringing the machine on site.”
—Shaun Carman, Survey Manager, Granite Construction
Based on design data provided by Caltrans, Trimble’s Digital Services team prepared digital 3D models illustrating the bridge structures, adjacent earthworks and new utilities routing. Granite was able to view these models and visualize them in the actual landscape while on site using Trimble SiteVision high-accuracy positioning augmented reality technology on a mobile device. This real-time visualization continued to provide the project team with critical information about the design and conditions throughout the project.
“Using SiteVision pre-construction allowed us to visualize the new bridges, see how they would fit, and how we could stage our equipment,” said Shaun Carman, survey manager at Granite. “We saved time and money and reduced risk by optimizing the crane placement prior to bringing the machine on site.”
Granite used a range of integrated technologies, including Trimble total stations, Global Navigation Satellite System (GNSS) base and rover kits, and hand-held field controllers, to ensure accuracy, consistency and efficiency in the field and in the office. Global Positioning System (GPS) machine control was implemented on all blades and dozers to expedite excavating and grading, and Trimble Business Center software was used to make precise models to grade roadways based on Caltrans design plans.
During construction, the connected technologies enabled the teams to share data seamlessly, which allowed Granite and Caltrans to make decisions together. The models and augmented reality system also gave Granite's field teams the ability to visualize site hazards such as the high-pressure jet fuel line that ran under one of the bridge sections.
“Having consolidated, consistent data for construction helps fast-track the process.”
—Anthony Abitz, Project Manager, Granite Construction
Granite used Trimble Stratus software with drone data to map, measure and share accurate information about the worksites and assets. The data allowed Granite’s field crew to calculate earthworks quantities and create monthly progress reports so they could invoice in a timely manner.
Granite also delivered as-built models to Caltrans. The models for drainage inlets became critically important when the site flooded. With the digital as-builts, the field crew was able to use augmented reality to view the inlets underwater.
“Having consolidated, consistent data for construction helps fast-track the process,” said Anthony Abitz, project engineer at Granite, “On top of that, carrying the digital as-built model forward to share with asset managers means they don’t have to recreate all that valuable information when they need to operate and maintain the asset for decades into the future.”
Accelerating Asset Lifecycle Management
The Cosumnes River Bridge Replacement was the first project where the Caltrans design team shared both 2D plans and 3D models with a contractor, and the approach proved valuable by improving communication, coordination and planning for both groups.
“If you can connect internal and external teams with a single source of reliable data over time, it will drastically improve productivity and results will be a better-performing asset over the entire service life.”
—Aaron Chamberlin, Senior Transportation Engineer, Caltrans
Caltrans is continuing to expand its use of civil Building Information Modeling (BIM) models and collaborative contracts with contractors. By applying lessons learned, Caltrans is moving ahead with the development of a BIM Level 4 process, which includes scheduling data in the model to calculate the time each task or project phase should take. The agency is also continuing its efforts to leverage digital as-builts and, more strategically, to roll out the Caltrans Asset Lifecycle Management System (CALMS) statewide initiative, which will use digital technologies to connect data and workflows across all phases of the asset lifecycle—from design and construction to operations and maintenance.
“The success of the Cosumnes River Bridge Project validated what we suspected all along: if you can connect internal and external teams with a single source of reliable data over time, it will drastically improve productivity and the result will be a better-performing asset over the entire service life,” said Caltrans’ Aaron Chamberlin.
With California’s statewide asset lifecycle management strategy, the DOT “will use digital technologies and data to connect people and processes across our programs and divisions,” explained Chamberlin. “That will be a win for future projects and a win for the quality and affordability of the assets long term.”
Adrien Patanè has 20 years of experience working with transportation and construction technologies on complex and environmentally sensitive projects across Australia, Europe, Asia and the Americas. As technology solutions manager for Trimble’s owner and public sector, he plays a key role in helping DOTs and contractors implement 3D construction workflows and other innovative technologies better, safer, faster, and greener.
This article originally appeared in Transportation Builder magazine (March-April 2023). Republished here with permission.