Henderson Waves Bridge
A Sinuous Architectural Marvel in Malaysian Balau
This engineering feat of the bridge comprises four distinct sections which include seven undulating curved steel ribs; supporting hollow sectioned vibration-dampening steel frames; hardwood deck with curved balustrades, wooden seats and alcoves all made with Malaysian Balau and steel balustrades. The undulating curved steel ribs form a 'wave' that alternately rises over and under its deck. The curved ribs form alcoves that function as shelters hugging seats within.
The bridge's sinuous curves, designed to look like three-dimensional waves, and its 1,500-square-meter (16,145 sq ft) hardwood deck required a great variety of different modular panels to form the complex dimensions. Five thousand pieces of 70 mm (2.76") x 32 mm (1.26") Balau modular boards were used to clad the bridge in areas meant for interaction between man and material, such as the walkway, alcove seating and sidewalls. The boards were fabricated with remarkable precision using proprietary software, which provided exact dimensions of the surface at regular 500mm (20" nominal) intervals to reduce wasted material. Each board varies by a single degree every 10 meters (approx. 108 ft) and many were tapered to measure. Timber specialist Venturer Pte Ltd of Singapore supplied the Balau strips, which were certified as originating from sustainable sources by Certisource, a UK-based timber legality verification standard.
The project brief called for the visible timber surfaces to appear seamless and homogeneous without showing any of the fixtures and fittings, and for the gaps between the timber strips to be narrow enough to prevent coins from slipping through. A stainless steel dowel and epoxy end-fixing method was adopted to conceal fixtures while a special "floating batten" was employed to drain water runoffs and yet prevent objects from passing through the gaps.
Every effort has been worthwhile as it is indeed an emotive experience to walk across this sinuous architectural marvel, especially at night when the full length of the bridge and its sensuous waves are lit in warm LED lighting. The Henderson Waves won the Singapore President's Award for "Design of the Year" in 2009. It is a perfect blend of timber craftsmanship with engineering know-how, resulting in a highly creative, breathtaking, functional and interactive structure for daily human use and enjoyment.
BALAU (Shorea) is a heavy hardwood of Strength Grade 1, also known as Selangan Batu. Sapwood is lighter in colour, sharply defined from naturally durable heartwood, which is yellow or grey-brown and darkens to deep brown on exposure. Density is 850-1,155 kg/m³. It is resistant to treatment with preservatives. Texture is fine and even, with deeply interlocked grain. It is suitable for all forms of heavy construction.
Malaysian Timber Council
Frequently asked questions
What wood species was used for the Henderson Waves Bridge deck?+
The bridge's hardwood deck, curved balustrades, wooden seats and alcoves were made with Malaysian Balau, a heavy hardwood also known as Selangan Batu.
How many Balau boards were used to clad the Henderson Waves Bridge?+
Five thousand pieces of 70 mm x 32 mm Balau modular boards were used to clad the walkway, alcove seating and sidewalls of the bridge.
How was the Balau timber for Henderson Waves Bridge verified as sustainable?+
Timber specialist Venturer Pte Ltd of Singapore supplied the Balau strips, which were certified as originating from sustainable sources by Certisource, a UK-based timber legality verification standard.
How were fixtures concealed on the Henderson Waves Bridge timber surfaces?+
A stainless steel dowel and epoxy end-fixing method was used to conceal fixtures, while a special 'floating batten' drained water runoff and prevented objects from passing through the gaps between timber strips.
How were the Henderson Waves Bridge timber boards fabricated to fit the curved design?+
The boards were fabricated using proprietary software that provided exact surface dimensions at 500 mm intervals to reduce waste. Each board varies by a single degree every 10 meters, and many were tapered to measure.
What are the properties of Balau (Shorea) hardwood?+
Balau is a Strength Grade 1 heavy hardwood with a density of 850-1,155 kg/m³. Its heartwood is yellow or grey-brown, darkening to deep brown on exposure, with fine, even texture and deeply interlocked grain, making it suitable for all forms of heavy construction.