• Arup Singapore Pte. Ltd.

    Tanjong Pagar Mixed Development – Guoco Tower

    Singapore

Project Summary

Project

Arup Singapore Pte. Ltd. was contracted to provide civil and structural services for the SGD 3.2 billion Guoco Tower development, a 64-story, 290-meter mixed-use office and residential tower that would become the largest in Singapore. The project also includes a medium-rise hotel block, a six-story podium, and a three-story basement that would link with an existing Mass Rapid Transit station. The government mandated that excavation and construction of the foundation limit movement of the station and existing buildings to less than 15 millimeters and 25 millimeters respectively. But, the variable nature of soil in the area made projecting performance difficult using traditional methods.

Solution

As Arup Singapore had to examine varying soil conditions under a tight deadline, the project team began the process with a comprehensive geotechnical study of the surroundings. The resulting report indicated that the development would require a pile-raft foundation, with a sequential excavation process in four sections. By analyzing the collected data and creating 3D simulations, the project team was able to predict soil stresses and the interaction of the foundation with the nearby structures. Individual simulations of the performance of each pile predicted how the tower would settle over time and how thick the raft should be to support each section of the development.

Outcome

To speed up construction, Arup Singapore performed the excavation in four phases. The detailed soil analysis allowed Arup Singapore to optimize the placement of each pile and reduce each load by 30% to 35%. Through accurate measurement of soil competition, the project team could omit a planned soil berm and inclined corner struts while maintaining the same amount of strength. Despite the massive amount of soil movement from the excavation, plans created using the geotechnical analysis kept movement of the transit station and the existing buildings well below government requirements. The tower is now fully completed and occupied, and its design is expected to serve as a reference point for similar developments in the future.

Software

Arup Singapore carried out its initial sub-soil analysis using Bentley's gINT geotechnical and geoenvironmental software and used it to manage all geotechnical data throughout its work. By using gINT, the project team issued a full interpretive report analyzing all properties and risks only one week after completing ground investigation works. gINT and sensor data were used to produce soil simulations within PLAXIS, which acted as an all-in-one soil and structure response solution and eliminated the need for other software platforms. Analysis in PLAXIS helped the team minimize soil movement and find ways to strengthen and streamline the foundation design.

Project Playbook: gINT, MicroStation, PLAXIS

Outcome/Facts
  • Arup Singapore used gINT to analyze varying soil compositions and improve soil-movement modeling, which allowed future performance for the 64-story, 290-meter tower to be predicted more accurately during excavation and construction.
  • 3D modeling in PLAXIS helped the project team streamline support structures, reduce the load on bored piles by 30% to 35%, and save significant time.
  • Arup Singapore determined excavation should be undertaken in four phases, which kept soil movement around existing structures well below government limits and minimized the impact to existing structures and an operating mass transit station.
Quote:
  • “Bentley’s geotechnical software enhanced the design methodology and drove efficiencies through digital workflows, which helped us to deliver a safe and cost-effective solution for basement construction, as well as resolve site issues and challenges encountered during construction.”

    Ei Sandar Aung Win Senior Geotechnical Engineer Arup Singapore