An iconic expressway
Amy Heffner, Director of Industry Marketing, Bentley Systems
THE Cebu-Cordova Link Expressway (CCLEX) is a combined toll bridge and causeway stretching 8.9km across the Mactan Channel, making it the longest and tallest bridge structure in the Philippines. Connecting the city of Cebu to Cordova on the island of Mactan, CCLEX has reduced travel times between Mactan and Cebu International Airport by 40 minutes.
Prior to implementing this project, Cebu was only connected to Mactan through two bridges in the northern area. This third inter-island connection in the south is relieving traffic congestion on the two original bridges and improving regional tourism and the economy.
As part of a temporary design joint venture, SENER, the lead engineering firm, provided detailed engineering design, while managing the multi-organisational design teams with the offer of technical assistance during construction.
The project includes designing a four-lane superhighway, featuring several bridges and access viaducts connecting to the main cable-stayed bridge, making it a spectacular sight and facilitating commerce throughout the region.
Complex site conditions, structural integration, and construction sequencing
Heralded as one of the most ambitious infrastructure projects in the Philippines, CCLEX presented site challenges, including extreme seismic conditions and a unique marine environment. The area is prone to typhoons with winds as strong as 250km per hour, requiring a structural design that can withstand the high seismic activity.
Working in an open digital environment allowed the geotechnical and bridge design and construction teams to share information and determine the optimal bored pile diameters for the main bridge and viaducts.However, with design teams across multiple organisations working on the project, the client faced design compatibility issues when connecting the viaducts to the main bridge structure.
Since the approach viaducts connect with support at the mid-span of the bridge, special coordination needed to be developed to ensure a joint and compatible design. It meant effective interaction was a key factor in obtaining a balanced design.
Another challenge was that the project needed to be constructed entirely over water on a tight timeline. This complex construction sequence required software that could integrate with all design parameters to develop models that incorporated modifications from the construction site.
The client realised that it needed flexible, interoperable bridge modelling software.
A collaborative digital solution
The client selected Bentley Systems’ OpenBridge based on its flexibility, collaborative design capabilities, and automated calculation features. Coordinated multidiscipline modelling and analysis enabled them to make the geometry adjustments that would ensure design compatibility between the structures.
Based on the detailed calculations, the design teams reduced the dimensions of the foundations and minimised the impact on the coral seabed.
Working in an open digital environment allowed the geotechnical and bridge design and construction teams to share information and determine the optimal bored pile diameters for the main bridge and viaducts. They also ensured that the structural solutions could withstand the seismic conditions and 250km per hour winds.
The software was also used to conduct detailed structural checks, which ensured that each structural element was correctly developed and verified.
Meanwhile, automating post-processes allowed the team to have complete control of the design schedule, adjusting resources and tasks as necessary. The software’s versatility, interoperability, and intelligent modelling and analysis facilitated a fast-track design process and model-based construction workflows to address the complex construction sequence and constrained project schedule.
Digitisation
Implementing collaborative digital modelling and analysis processes using the software streamlined workflows, enabling the client to develop the models and meet the project schedule. Its flexibility to update models simplified the geometry adjustments required for design compatibility. This capability reduced coordination time between design teams and allowed them to achieve quality digital designs.
Based on the detailed calculations, the design teams reduced the dimensions of the foundations and minimised the impact on the coral seabed. Having highly accurate models in an open digital platform facilitated collaboration with the construction team, optimising time on site.
Furthermore, the automated postprocesses, enabled the client to efficiently generate calculation reports, saving 30% in time and costs.
Working in Bentley’s connected digital environment also improved review and approval efficiencies, accelerating approvals of different parts of the project, enabling construction to begin in the shortest possible time.
The intermediate control steps enabled by the software, together with the quality control sheets, made internal verification efficient and traceable.
Amy Heffner, Director of Industry Marketing, Bentley Systems
All images courtesy of ©SENER.