Incorporating BIM Methods into Every Part of Road and Pipeline Design Saved Time and Expense
Finding Space for New Roads in a Tight Environment
To address traffic congestion in the city of Chengdu, China, Chengdu Urban Construction Investment Management Group Co., Ltd. (CUCIMG) was tasked with designing a CNY 1.38 billion infrastructure redevelopment package.
The centrepiece of the package is a 4.3-kilometre roadway system that will integrate 64 existing roads, with the main new road designed for speeds of 60 kilometres per hour and new auxiliary roads designed for 40 kilometres per hour. It would also include new and reworked intersections to optimise traffic flow and accommodate the varying road speeds. The organisation would need to construct new bridges, tunnels, green spaces, and pedestrian paths, as well as redevelop existing pipeline networks and add a new tunnel for power distribution.
However, CUCIMG faced numerous challenges. Since the project was slated for a heavily developed commercial area, planning the best routes to optimise traffic became difficult. Overpasses could affect existing buildings, while underpasses had to be built around the Jin River, a subway system with two stations in the area, and the power tunnel. Ultimately, a 35-metre underpass would have to be constructed less than two metres from the subway, which required redeveloping the affected subway section. To accommodate new roads and belowground construction, various types of pipelines and cables—including those moving sewage, rainwater, electricity, gas, and data—would have to be either temporarily moved or permanently moved, or protected during construction. The design team also needed to design a safe pedestrian passage system near the highly trafficked roads.
Preliminary planning around the Jin River, dense buildings, pipelines, a subway line, and two subway stations became increasingly complex. Therefore, the project team determined that traditional 2D CAD drawings were not efficient enough to finish the design within the three-month deadline. Additionally, during previous CUCIMG projects, 2D design hindered coordination among contributors with varying specialties and produced many hidden clashes between design elements. Though CUCIMG created 3D models at the end of the design process, the organisation discovered that the late-stage models produced limited value for planning, reporting, construction, and management.
Overcoming Challenges through Visualisation
To overcome the project’s challenges and optimise designs within the tight timeframe, CUCIMG leveraged Bentley applications to incorporate BIM methodology into every step of the design process. The design team used unmanned aerial vehicles to capture images of the construction area, then created a reality mesh of the terrain, buildings, and underground elements using ContextCapture, as well as an existing digital model of the city of Chengdu. With the project surroundings visualised, the design team modelled potential designs with OpenBuildings, OpenRoads, and OpenBridge. By viewing plans in 3D, the design team could measure the effectiveness of each design and determine how to improve them.
CUCIMG used OpenRoads for multiple aspects of the project. In addition to laying out routes, determining intersections, and optimising traffic flows for 64 different roads, the design team used OpenRoads to build subway tunnel sections, underpass tunnels, and underground utility models. The design teams automated many design details to greatly improve work efficiency and speed the evaluation of each iteration. Additionally, the design team used OpenRoads to label pipes as retained, removed, or newly built, which helped eliminate clashes in pipe placement and underground development. With OpenBridge, the design team strengthened the foundations of bridge piles, while OpenBuildings was leveraged to restore all aspects of the subway system affected by construction.
A Single Source of Truth Saves Time and Money
Teams from numerous disciplines collaborated in ProjectWise to ensure a single source of truth. Individual models were brought together in LumenRT to form a digital twin that visualised all elements of the project. Though design teams worked in different file formats, CUCIMG used the interoperability of Bentley applications to seamlessly combine all contributions into a single format. Compared to traditional 2D modelling, 3D visualisation helped the design team improve designs and work efficiency. Additionally, the efficient visual twin presentation improved loading times and lessened hardware requirements compared to CUCIMG’s late-stage BIM presentations during past projects. The design team incorporated all necessary asset information for construction, operations, and maintenance into a digital twin, which is expected to extend the lifecycle of all assets.
By collaborating within ProjectWise, CUCIMG improved the design management process and increased internal work efficiency by 20%. ProjectWise also helped CUCIMG to detect and resolve 16 design clashes within the pipeline system. Automated design within OpenRoads reduced the construction drawing time by 120 resource hours. By using the digital twin to guide the construction process, the design team shortened the time required for planning, construction, and approval by 15%. Work with the digital twin determined that building the foundations of the elevated road and the underpass tunnel simultaneously would prevent problems during construction. In total, CUCIMG’s work with 3D modelling lowered design costs by 23% and construction costs by 10%.
Organisation: Chengdu Urban Construction Investment Management Group Co., Ltd.
Solution: Digital Cities
Location: Chengdu, Sichuan, China
- To design a CNY 1.38 billion infrastructure package, including 4.3 kilometres of new roads.
- To improve efficiency by incorporating BIM techniques throughout the design process.
Products Used: ContextCapture, Descartes, gINT, LumenRT, MicroStation, OpenBridge, OpenBuildings, OpenRoads, ProjectWise
- The CNY 1.38 billion infrastructure redevelopment project included building 4.3 kilometres of new roads, pedestrian paths, and underground infrastructure.
- Building within the dense commercial area required minimising the impact of overpasses on buildings and constructing tunnels two metres away from a subway line.
- To manage the complex project, CUCIMG leveraged 3D modelling throughout the design, which was a first for the organisation.
- 3D visualisations of all project assets helped determine where to place bridge supports and how to connect 64 roads designed for varying speeds.
- A connected data environment improved work efficiency by 20%, detected and resolved 16 design clashes, and reduced drawing time by 120 hours.
- Overall, 3D modelling applications helped lower design costs by 23% and construction costs by 10%.
Quote: “Intelligent transportation and the digital model are the foundation of a digital city. Digital twins provide a lightweight model, which expands the use of BIM applications beyond the project to the delivery of digital assets. Digital twins can be directly applied to the owner’s planning, construction, demolition, and other management.”
Yanxiang Wang, BIM Application Engineer, Chengdu Urban Construction Investment Management Group Co., Ltd.