This ambitious project has transformed a former KMB bus depot in Kwun Tong, a traditional industrial district, into a dynamic mixed-use development.

It features two 20-storey office buildings, a 12-storey retail podium and a 4-level basement, located in a reclaimed area with a complex geology of soft, thick marine deposits and alluvium. 

Arup played a pivotal role in realising this fast-track project by providing expert structural and geotechnical engineering services. To expedite the construction process, we proposed a double top-down approach, enabling the concurrent construction of the superstructure and the basement. We also adopted innovative structural design approaches to improve constructability.

Encompassing a total GFA of 1.15 million ft2, this modern landmark is set to breathe new life into Kwun Tong, transforming it into a new business hub in Hong Kong.

Double top-down construction method 

We introduced a ‘double top-down’ approach to speed up the whole construction process. This method allowed for the simultaneous construction of the superstructure above ground, the ground floor to B2, and the deeper basement levels below B2. It also facilitated the early completion of the critical plantrooms in the basement.  

When building the foundation, bored piles were constructed up to the ground floor level. To accelerate progress, 28 of these bored piles were extended to serve as basement columns, supporting the top-down construction. This approach simplified the structural connection and shortened the construction period.  

Embracing sustainability and improving constructability 

Prefabricated modular struts and walings were adopted for the excavation and lateral support (ELS) works to minimise onsite welding. The size of the struts was standardised and over 95% of the connections used bolts and nuts. This not only enhanced the construction environment and quality of installation, but also sped up the installation process.  

We used concrete waling beams instead of conventional steel ones, blending them seamlessly with the basement walls. We also avoided using short struts to minimise water leakage risks at the interface with basement walls and reduce onsite welding. These innovative approaches simplified the connections between the basement floor and the bored pile columns, hence significantly accelerating the construction schedule.