James Law Cybertecture International | Henderson Centre
Driven by the initiative to design an enriching space for extensive research and development purposes, the core concept embarked is to have a large leaf-shaped roof feature that will shelter and help store rainwater. The leaf-shaped roof functions alike an organic leaf which processes and support life thru photosynthesis, by absorbing and converting energy from the sun, and providing enough energy for a self sustainable environment.
The installation at vertical facade facing north enhances an absorbing effect for sunlight to penetrate to the interior when natural light vertical facade comprises with redirection device and special shape of reflective ceiling. Horizontal louvers feature as an effective sun-shading device with fixed glass panel installed at vertical facade facing south.
Hybrid Cooling System
The integration of an intelligent hybrid GSHP cooling system facilitates a flexible and efficient regulation of room temperature. Utilizing the large site footprint for efficient heat rejection into the earth and backed up by a air cooled mode. Earth cooling can provide sufficient heat rejection during office hours, whilst the cooled air efficiently acts as a booster during evening and exhibition mode.
Solar Cooling System
A visionary form of futuristic cooling system is in place whereby a form of renewable cooling uses the solar energy from the sun to produce hot water, and converted with a physical chemistry process, this thermal energy then can be transformed into cooling energy with minimal use of external electricity as input.
The innovation of sustainable rooftop enables the collection of rainwater in the large gutter running the length of the roof and deposits this rainwater into a reinforced concrete cistern within the southeastern beam. From this cistern, the rainwater can be distributed to filtration equipment and then used for toilet flushing, landscape irrigation, and cleansing purposes. The operation is flexibly enabled when the facility is in construction mode and show suites are being constructed, emitting dust, VOCs and other environmental pollutants from these activities. By accommodating an open air channel for ventilation, the HVAC system is temporarily disabled to prevent contamination during this mode of operation.
The structural design philosophy is to create a sturdy demountable structure that meets all requirements of the Hong Kong Building Department for permanent structures. Wherever practical connections will be bolted. Corrosion protection will be provided to maintain serviceability of the connections for future demountability. The basic structure is a braced steel frame, with rectangular hollow steel columns (300mm SHS) on a 9mx9m grid supported off precast reinforced concrete pads. There is a grillage of beams with bolted connections at roof level to support the lightweight metal roof. It is expected that there will be lightweight planting areas on the roof, but that there will not be public access. The ground floor slab consists of precast concrete planks with an insitu topping for structural robustness supported on a grillage of bolted steel beams that span between the columns.
The steel beams at roof level are 800mm deep castellated beams (cut from standard sections) so that services can be run within the structural depth, providing flexibility of location and leaving the maximum possible usable height. The tapered cantilevers supporting the significant roof overhangs could either be solid web or castellated (using the “Cellform” process).
The steel beams at ground floor level are rolled sections (UB610), but could also be castellated. These will be bolted to the steel columns and will support pre-stressed precast concrete slabs (200mm thick). There is no need for a structural RC topping. A robust connection is provided by means of locating tabs on the tops of the steel beams.
The columns will be rectangular hollow sections (300mmx300mm) to provide slender elevations that are resistant to buckling, which is important considering the high ceiling. They will be bolted to the precast concrete pad foundations. This can be a bolted connection to limit the overturning moment in the pads.
Lateral stiffness is provided by braced bays (four in each direction). The bracing will be provided by bolted steel sections (203UC cross-bracing). This is more efficient than providing moment connections throughout especially since the height of the roof beams is variable and would result in unsatisfactory variable stiffness across the building plan.
There is a concrete retaining wall round part of the perimeter. This provides shielding and shading for the building. It is intended that the retaining wall consist of segmented precast reinforced concrete elements (variable length by 3m tall by 3m deep with 300mm thickness) that can be precast and transported to site by lorry.
Most of the structural components will be manufactured and finished off-site under factory conditions. Erection could be carried out using a mobile crane and mobile platforms. While the components are under preparation the site will be prepared to formation levels. Reinforced concrete on the site will be crushed and used as hard-core fill for the column and wall foundations. A thin blinding will be placed on the hard-core to provide the required levels. Once the founding level is prepared, the precast concrete foundation pads (with cast-in anchor bolts) will be trucked in (stacked vertically) and located on the hardcore with blinding. The precast concrete retaining walls could be brought in at this point. Once the pads are in place, the columns will be trucked in, located on the pads (on the cast-in bolts) and bolted into place. Tolerances will be provided to suit the addition of the steel beams. Once the columns are in place, the steel beams can be brought in and bolted to them, followed by the bracing. The concrete slabs will then be placed on the ground level beams and the purlins will be bolted to the roof beams.
Finishes will be removed using mobile platforms. The roof decking will be unbolted and removed using a mobile crane. Once the decking is off, the purlins will be unbolted and removed, followed by the bracing and the roof beams. Once the roof has been removed, the precast floor slabs can be lifted off, and the floor beams can be unbolted and removed. Finally the columns can be un-bolted and removed leaving the foundation pads that can also be lifted and removed. The retaining walls can be revealed by removal of the earth, and the segments can then be lifted onto lorries and removed. The blinding and hard-core can be broken out and reused for hard-core in another location.