MyOralPresentationonBridges

=**Kurilpa Bridge Presentation** = = = **http://www.youtube.com/watch?v=1kUvBnrALW0**



Typical building construction, use, and demolition, as well as the manufacturing of building materials, contribute significantly to environmental problems. In the United States, buildings account for:
 * Did you know?**
 * 36% of total energy use
 * 65% of electricity consumption
 * 30% of greenhouse gas emissions
 * 30% of raw materials use
 * 30% of waste output (equal to 136 million tons annually)
 * 12% of potable water consumption
 * A typical 1700 sq. ft wood frame home requires the equivalent of clear cutting one-acre of forest

Despite all these intensive inputs, we are not constructing healthy buildings. More than 30% of buildings in the US have poor indoor air quality, a serious problem given that most people spend about 90% of their time indoors By the year 2010, another 38 million buildings are expected to be constructed in the US, bringing the country’s total to over 100 million. The challenge is to build those new buildings, and renovate the older ones, in ways that reverse these unhealthy trends. Fortunately we can respond to this challenge by building green, we can assist in preserving natural habitats, watersheds, and ecosystems, protect air and water quality, reduce greenhouse gas emissions and solid waste, all while conserving natural resources and creating healthier indoor and outdoor environments. But building only buildings is not enough, we need to put a little green in every construction and that is what the Kurilpa Bridge in Australia is all about. Not only can we improve the global environment, building green can improve your local environment. Baulderstone was chosen to design and construct the iconic Kurilpa Bridge with local architects Cox Rayner and engineering consultants Arup as part of the design team. The Kurilpa Bridge is now a pedestrian and cycle bridge in Brisbane’s inner city, linking the city centre and South Brisbane. Maybe the most important characteristic of this bridge is that, the way it was designed definitely enforces the green "Hey you! This bridge is made for walking" attitude. The energy-saving lighting system is powered by 84 solar panels that collectively generate a daily output of about 100KWh and an average yearly output of 38MWh. The solar energy generates supplies 75% of the power required to run the LED setup in the fully lit mode, but in most lighting configurations, 100% of the energy required will come from the solar panels. Surplus electricity generated by the solar array will be returned to the main grid. The bridge stretches from the North Quay end of Tank Street to Kurilpa Point in South Brisbane, adjacent to the new Queensland Gallery of Modern Art. The bridge is based on the principles of tensegrity, an architectural and engineering system in which the structural integrity is a synergy between balanced tension and compression components. This produces a lightweight yet strong and stable structure. The new bridge presents an artistic array of cables and flying struts recalling the ropes and spars of sailing ships and boats. Offering expansive views of the river, it features two large viewing and relaxation platforms, two rest areas, and a continuous all-weather canopy for the entire length of the bridge. The new Kurilpa Bridge’s delicate and elegant design is expected to sit well with the new Gallery of Modern Art and Kurilpa Point, providing an environmentally friendly and enjoyable walking and cycling pathway to the city from South Brisbane, a significant place for the local Indigenous community. Sculptural in appearance, the bridge is a multi-mast, cable-stay structure, a first in city bridge construction. It is built from more than 1,500m3 of concrete, 550t of steel and cabling totalling more than 6.8km. The bridge is 470m long with a main span of 120m. On the northern side, it soars over the CBD expressway, linking pedestrians to parklands and Brisbane’s justice precinct. On the southern side, it was designed to float across the river bank, spiralling before landing at the new Gallery of Modern Art mentioned before. While the geometry of the bridge is informal, the cables (in tension) and tubes (in compression) are arranged with a structural rhythm, a logic similar to all tensegrity forms but with the added resilience of reliable infrastructure. Arup is a leader in applying the complex analysis required to generate suitable geometry for tensegrity-inspired structures. The bridge was completed in September and opened in October 2009. A public competition was held to decide on a new name for the bridge. On the 23rd November 2008 it was announced that the winning entry was Kurilpa Bridge. Baulderstone Kurilpa Bridge Project Manager Paul Stathis says, that it was a combination of the engineers wanting the challenge of building something very lightweight and efficient and the architects wanting to build something that wasn’t just a ‘run-of-the-mill’ concrete bridge. “It’s not just unique in appearance, it’s unique in design and engineering,’’ Stathis says. He says that while each of the 12.8m bridge deck segments are uniform, the cables that support the bridge differ in length, angle and load, creating engineering challenges. “We are building the bridge deck piece by piece, night by night. Every element that’s installed is random, with the exception of the deck and the crossbeams – but the work is definitely not speculative or random,” Stathis says.