ConstructioNews
Vol 33 No 3 (01-2024)
Joint Cavern Development at Anderson Road Quarry Site - The first cavern development project adopting MiC
To support the sustainable development of Hong Kong, it is the established policy of the Government to adopt a multi-pronged approach to enhance land supply. The hilly and hard rock terrain of Hong Kong makes it highly suitable for development of caverns under appropriate geological conditions.
Cavern construction is a mature technology that has seen continual extension in its applications. There are various government facilities accommodated inside caverns in Hong Kong, including Stanley Sewage Treatment Works, Island West Transfer Station, Western Salt Water Service Reservoir and Kau Shat Wan Explosives Depot, etc. Also, the Government is taking forward a number of projects for relocating/accommodating government facilities in caverns, such as the Relocation of Sha Tin Sewage Treatment Works and Diamond Hill Fresh Water and Salt Water Service Reservoirs to Caverns, which are at the construction stage.
In December 2021, the Civil Engineering and Development Department commissioned the study on “Joint Cavern Development at Anderson Road Quarry Site – Reprovisioning of Public Works Central Laboratory and Building of Government Records Service’s Archives Centre – Investigation, Design and Construction”. The study includes the Relocation of Public Works Central Laboratory to caverns and the Building of Government Records Service’s Archives Centre in caverns.
Given the extensive rock face in Anderson Road Quarry Site, the site is suitable for cavern development. The site also provides a readily-available platform in front of the rock face, thereby shortening construction costs and time. Moreover, the site will be served by forthcoming infrastructure and transportation facilities, which would provide ease of access for future staffs and visitors.
This is the first time in Hong Kong that caverns are utilised to serve non-infrastructure related facilities along with other innovative construction methods. This project will adopt Modular Integrated Construction (MiC) to shorten the construction period.
Scope of Works
The works mainly include the design and construction of caverns inside the mountain body of Tai Sheung Tok at the Anderson Road Quarry Development site for co-locating the Public Works Central Laboratory and the Government Records Service's Archives Centre, and the demolition of the existing Public Works Central Laboratory Building in Kowloon Bay. The works commenced in July 2023 for completion in 2028.
1) Relocation of Public Works Central Laboratory to caverns
The proposed works comprises –
i) Construction of a cavern complex and connection adits of about 6,000 square metres in area and about 160,000 cubic metres in total volume inside the mountain body of Tai Sheung Tok at the Anderson Road Quarry Development site;
ii) Construction of a 3-storey Public Works Central Laboratory (PWCL) Building inside caverns and at the portal (about 2,000 square metres in site area), including its structure and foundation, building services and installation of furniture and equipment for accommodating the relocated PWCL and laboratories of the Product Testing and Dutiable Commodities Section of Government Laboratory;
iii) Demolition of the existing PWCL Building at Kowloon Bay; and
iv) Other related works, including landscaping works.
2) Building of Government Records Service’s Archives Centre in caverns
The proposed works comprises –
i) Construction of a cavern complex and connection adits of about 6,500 square metres in area and about 190,000 cubic metres in total volume inside the mountain body of Tai Sheung Tok at the Anderson Road Quarry Development site;
ii) Construction of a 4-storey Archives Centre inside caverns (3 storeys at this portion) and at the portal (about 2,000 square metres in site area), including its structure and foundation, building services, installation of automated storage and retrieval systems, furniture and equipment; and
iii) Other related works, including landscaping works.
Application of Innovative Construction Methods
1) Modular Integrated Construction (MiC)
To enhance the construction programme, Modular Integrated Construction (MiC) will be adopted in this project. With the concept of “factory assembly followed by on-site installation”, modules are manufactured and completed in the factory first before they are transported to the site for installation. This can reduce the on-site works and expedite construction progress.
This is also the first time in Hong Kong that caverns are utilised to serve non-infrastructure related facilities along with other innovative construction methodologies. Therefore, the construction of the portion of the Public Works Central Laboratory and Archive Centre within the caverns employing MiC will be facing many challenges imposed by the spatial constraint within caverns, limited surface working space at the portal, and restricted working conditions with the presence of many sensitive receivers nearby as well as the related complex logistics planning anticipated.
2) Early Contractor Involvement (ECI)
In view that this project is the first cavern development project adopting MiC, Early Contractor Involvement (ECI) is adopted in this project to identify the potential issues earlier, and address them in an interactive process to eliminate potential claims and delays during construction as far as possible.
Environmental Mitigation Measures
The Environmental Protection Department issued an environmental permit for the construction and operation of the works in July 2022. Contractors will implement the
environmental mitigation measures recommended in the environmental permit.
The mitigation measures mainly include completion of the cavern formation works before the population intake of housing development sites opposite to the works, installation of blast doors at the portals of adits, carrying out drill and blast works with blast doors fully closed, carrying out blasting works outside sensitive hours and no more than once daily, and installing effective dust filters and collectors in ventilation and exhaust systems to control dust during construction. There will not be any temporary explosives storage on or near the site.
Effective Use of Land Resources
The special environment of caverns is suitable for accommodating facilities which require a secure and stable operating environment (for example, testing laboratories, archives, data centres and warehouses, etc.). Strong cavern walls can protect the facilities from natural or man-made disasters. The temperature and humidity inside caverns are also relatively stable throughout the year, and the facilities can be sheltered from being affected by sunlight and weather changes, thereby reducing the power consumption from the cooling system of the facilities and the carbon emissions. This not only reduces the operational costs, but also fosters Hong Kong to becoming a green city.
In order to bring about better coordination between “Building of Government Records Service’s Archives Centre in cavern” and “Relocation of Public Works Central Laboratory to caverns” and minimise potential nuisance to the neighbourhood and interface issues, these two adjoining projects are implemented together. As compared to taking forward the two projects separately, this joint cavern development arrangement can ensure the effective use of the scarce land resources, reduce coordination issues between different projects and streamline the work of managing works contracts, thereby enhancing the overall cost-effectiveness.
Source of information & picture: Website of Civil Engineering and Development Department
Cavern construction is a mature technology that has seen continual extension in its applications. There are various government facilities accommodated inside caverns in Hong Kong, including Stanley Sewage Treatment Works, Island West Transfer Station, Western Salt Water Service Reservoir and Kau Shat Wan Explosives Depot, etc. Also, the Government is taking forward a number of projects for relocating/accommodating government facilities in caverns, such as the Relocation of Sha Tin Sewage Treatment Works and Diamond Hill Fresh Water and Salt Water Service Reservoirs to Caverns, which are at the construction stage.
In December 2021, the Civil Engineering and Development Department commissioned the study on “Joint Cavern Development at Anderson Road Quarry Site – Reprovisioning of Public Works Central Laboratory and Building of Government Records Service’s Archives Centre – Investigation, Design and Construction”. The study includes the Relocation of Public Works Central Laboratory to caverns and the Building of Government Records Service’s Archives Centre in caverns.
Given the extensive rock face in Anderson Road Quarry Site, the site is suitable for cavern development. The site also provides a readily-available platform in front of the rock face, thereby shortening construction costs and time. Moreover, the site will be served by forthcoming infrastructure and transportation facilities, which would provide ease of access for future staffs and visitors.
This is the first time in Hong Kong that caverns are utilised to serve non-infrastructure related facilities along with other innovative construction methods. This project will adopt Modular Integrated Construction (MiC) to shorten the construction period.
Scope of Works
The works mainly include the design and construction of caverns inside the mountain body of Tai Sheung Tok at the Anderson Road Quarry Development site for co-locating the Public Works Central Laboratory and the Government Records Service's Archives Centre, and the demolition of the existing Public Works Central Laboratory Building in Kowloon Bay. The works commenced in July 2023 for completion in 2028.
1) Relocation of Public Works Central Laboratory to caverns
The proposed works comprises –
i) Construction of a cavern complex and connection adits of about 6,000 square metres in area and about 160,000 cubic metres in total volume inside the mountain body of Tai Sheung Tok at the Anderson Road Quarry Development site;
ii) Construction of a 3-storey Public Works Central Laboratory (PWCL) Building inside caverns and at the portal (about 2,000 square metres in site area), including its structure and foundation, building services and installation of furniture and equipment for accommodating the relocated PWCL and laboratories of the Product Testing and Dutiable Commodities Section of Government Laboratory;
iii) Demolition of the existing PWCL Building at Kowloon Bay; and
iv) Other related works, including landscaping works.
2) Building of Government Records Service’s Archives Centre in caverns
The proposed works comprises –
i) Construction of a cavern complex and connection adits of about 6,500 square metres in area and about 190,000 cubic metres in total volume inside the mountain body of Tai Sheung Tok at the Anderson Road Quarry Development site;
ii) Construction of a 4-storey Archives Centre inside caverns (3 storeys at this portion) and at the portal (about 2,000 square metres in site area), including its structure and foundation, building services, installation of automated storage and retrieval systems, furniture and equipment; and
iii) Other related works, including landscaping works.
Application of Innovative Construction Methods
1) Modular Integrated Construction (MiC)
To enhance the construction programme, Modular Integrated Construction (MiC) will be adopted in this project. With the concept of “factory assembly followed by on-site installation”, modules are manufactured and completed in the factory first before they are transported to the site for installation. This can reduce the on-site works and expedite construction progress.
This is also the first time in Hong Kong that caverns are utilised to serve non-infrastructure related facilities along with other innovative construction methodologies. Therefore, the construction of the portion of the Public Works Central Laboratory and Archive Centre within the caverns employing MiC will be facing many challenges imposed by the spatial constraint within caverns, limited surface working space at the portal, and restricted working conditions with the presence of many sensitive receivers nearby as well as the related complex logistics planning anticipated.
2) Early Contractor Involvement (ECI)
In view that this project is the first cavern development project adopting MiC, Early Contractor Involvement (ECI) is adopted in this project to identify the potential issues earlier, and address them in an interactive process to eliminate potential claims and delays during construction as far as possible.
Environmental Mitigation Measures
The Environmental Protection Department issued an environmental permit for the construction and operation of the works in July 2022. Contractors will implement the
environmental mitigation measures recommended in the environmental permit.
The mitigation measures mainly include completion of the cavern formation works before the population intake of housing development sites opposite to the works, installation of blast doors at the portals of adits, carrying out drill and blast works with blast doors fully closed, carrying out blasting works outside sensitive hours and no more than once daily, and installing effective dust filters and collectors in ventilation and exhaust systems to control dust during construction. There will not be any temporary explosives storage on or near the site.
Effective Use of Land Resources
The special environment of caverns is suitable for accommodating facilities which require a secure and stable operating environment (for example, testing laboratories, archives, data centres and warehouses, etc.). Strong cavern walls can protect the facilities from natural or man-made disasters. The temperature and humidity inside caverns are also relatively stable throughout the year, and the facilities can be sheltered from being affected by sunlight and weather changes, thereby reducing the power consumption from the cooling system of the facilities and the carbon emissions. This not only reduces the operational costs, but also fosters Hong Kong to becoming a green city.
In order to bring about better coordination between “Building of Government Records Service’s Archives Centre in cavern” and “Relocation of Public Works Central Laboratory to caverns” and minimise potential nuisance to the neighbourhood and interface issues, these two adjoining projects are implemented together. As compared to taking forward the two projects separately, this joint cavern development arrangement can ensure the effective use of the scarce land resources, reduce coordination issues between different projects and streamline the work of managing works contracts, thereby enhancing the overall cost-effectiveness.
Source of information & picture: Website of Civil Engineering and Development Department