The Tung Chung New Town Extension(TCNTE) project is currently underway and it will create more than 130 hectares of land through reclamation. Ir CHENG Ting-ning, Albert, Executive Director of the Construction Industry Council, together with CIC’s staffs visited the TCNTE reclamation site in early July, to get a better understanding on how the project teams employed different technologies to balance conservations and developments, and using digital management methods to uplift productivity and safety standard. TCNTE is the first new town project via reclamation since 2003. The project covers the areas on the eastern and western flanks of the existing Tung Chung New Town. It will provide approximately 62,100 residential flats for a population of about 184,000. It will also provide about more than 877,000 square metres of gross floor area for office, retail and hotel use, hence creating 40,000 employment opportunities. The reclamation works for about 130 ha of land were commenced at the end of December 2017. The project is making good progress and is expected to finish in 2023. The first two parcels of land formed by reclamation were handed over to the Housing Department in March and October 2020 for the development of public housing units. Since then, more parcels of land were delivered for the purposes of housing, commercial and integrated development.
The Adoption of Deep Cement Mixing method
There is always a debate on the coexistence of development and conservation, while the TCNTE project team has adopted advanced environmental-friendly technologies to ensure that balance can be striked. Different from the traditional method of dredging or removing the marine mud which would easily cause pollution, the TCNTE project team employed the non-dredged “Deep Cement Mixing” (DCM) method, which involves the inection of cement slurry from mixing shafts on the works vessel into marine mud, mixing them with the soft marine mud while rotating. The marine mud will then be solidified to form a strong cement mixing column, which will form a DCM treatment zone in the seabed to support the seawall to be constructed above. Compared to the conventional method, the use of DCM is able to lessen the impact of reclamation on water quality and marine ecology nearby, and carbon emission is also reduced as no sea transport is required for dumping the marine mud.
Eco-shorelines enhance biodiversity
In order to mimic the physical properties of the natural inter-tidal zone, the TCNTE project team will set up three types of eco-shorelines of total length about 3.8km along the new shoreline, namely mangrove eco-shoreline, rocky eco-shoreline and vertical eco-shoreline. In common practice, artificial shorelines mainly consist of vertical seawalls or rubble mound seawalls, which are not suitable for organic matters and micro-organisms to attach and grow, whereas the eco-shorelines will provide favourable conditions to improve biodiversity. During the visit, representatives from CIC took a boat trip to the trial site at Siu Ho Wan, where the TCNTE project team gathers data and information to refine the eco-shoreline design. Up till now, more than 20 species, including Lunella coronata granulata, Uca acuta and Periophthalmus modestus, are found to have settled on the eco-shorelines.
Digital Twin to assist management
The TCNTE project is expanding on a massive scale with more than 800 workers working on different frontlines, it is a must to employ innovative technologies to assist in management. An Innovation Hub called “InnoTCE” was set up as a result. The team utilised the Digital Twin technology to collect and consolidate different construction data and records through IoT sensors. These data and records are then simulated and projected as a real-time “digital twin” of the site in the virtual space with the help of BIM technology. This enables the project team to monitor the entire construction site in real time, allowing precise decision-making which would in turn enhance productivity and safety performance. More than 30 innovative technologies were introduced in various aspects of works, as the sites are close to the neighbourhoods, the team has to sought solutions to minimise the adverse impacts of the works. The TCNTE project is the first public works project to adopt a real-time tracking and monitoring system for dump trucks to deter illegal dumping. As tilting sensors and AI cameras were installed on trucks, the team could then monitor their locations and travelling routes, if any of them is suspected to be dumping waste at a non-designated location, the system would immediately notify the monitoring staff.
Effective monitoring in digital platforms
Data utilisation is crucial to the future of the construction industry, Ir Albert Cheng appreciated the close collaboration within the team to adopt digitalisation and create a “Smart Management Site" as he commented that “The team makes use of a digitalised system to monitor different aspects of the site like safety performances, quality, work progress and sustainability, as well as tirelessly seeking improvements with the help of the digital platforms. CIC is happy to see more sites to follow suit in employing innovative technologies, and wish that we can work together to improve the qualities, progress and safety performances of different sites across Hong Kong.”
