3 Ngong Ping 360 John Batchelor, Suresh Tank 15 Waste as ... - Arup

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583.5m Tower 5 44m Nei Lak Shan angle station 30m 161m Ngong Ping terminal 575.2m Prior to any construction works in the Ngong Ping area, the Ngong Ping stream, which flowed directly through the site, had to be diverted to run parallel to the site’s northern boundary and rejoin the existing watercourse immediately downstream of the terminal building. Approximately 390m of banks for the diverted stream were constructed of rectangular galvanized steel mesh gabion baskets, filled with crushed rocks excavated on site (Fig 21). Gabion mattresses for the stream bed were proposed by the Stage 2 designers, but were replaced by natural crushed rocks excavated on site to enhance the environmental and ecological value of the diverted stream. Additional calculations by Arup showed that the change to the stream bed lining would have no impact on the stream’s hydraulics. Detail design, government approval, and construction of the stream were all completed within five months of award of contract and before the 2004 rainy season commenced (Fig 22). 21. Stream diversion under construction, showing gabion baskets. 22. Ngong Ping stream diverted. Tower 6 27m 585.0m 23. Ngong Ping Village: the terminal building is on the right, with Ngong Ping sewerage treatment works (another Arup project) in the background. The terminal forms the start of the Ngong Ping cultural experience, and this is reflected in theming to complement the theme village itself. The superstructure of the latter’s buildings are in concrete with Chinese roof tiles, except for the main terminal building roof which is of structural steel with a standing seam metal finish. The terminal building frame is in reinforced concrete with one basement level. The terminal building accommodates the ticketing, pre-ride queuing and associated retail, covered walkway, plant, administration, and maintenance areas. Emergency vehicle access is provided around the building with the main utilities laid under footpaths. Ngong Ping theme village The theme village (Fig 23) has three areas of one and two-storey buildings with a traditional regional Chinese character. Maeda and Arup opted to replace the steel frames proposed by the Stage 2 designer with concrete frames to reduce cost and save time. Most of the design and drawing production for the village was carried out in Arup’s Shenzhen and Manila offices and checked by the Hong Kong office before being submitted to the BD for approval. The Arup Journal 1/2008 11
12 25. Detail of rescue trail timber construction. The Arup Journal 1/2008 26. A Kamov helicopter approaching Tower 3 (Hong Kong International Airport on Chek Lap Kok – also an Arup project - is in the background). 24. One of the six mules used for transporting loads up to 120kg on narrow trails in the country park. 974m Environmental considerations The project team put great emphasis on environmental considerations. The route alignment and the type of cable car system were both selected to minimize the number of towers required in the country park. Ecological surveys were carried out by others and protected species from the tower sites were relocated. Rather than build a haul road, helicopters and mules were used to transport materials. Six mules were specially brought from Alberta, Canada, to transport water, fuel, and construction materials on a narrow steep trail to NLSAS and Towers 6 and 7. The mules proved able to carry up to 120kg loads, and worked seven hours a day, six days a week, for 14 months (Fig 24). Due to the nature (and weight) of Ngong Ping 360’s construction materials, two types of helicopter were used, the French-built Lama and the Russian Kamov. The Lamas were used to transport mainly concrete and reinforcing bars to remote sites and could carry loads of up to one tonne. During peak periods, they operated up to seven and eight hours a day transporting materials to the remote tower sites in North Lantau Country Park. The Kamov (Fig 26) was brought to Hong Kong specifically for the Ngong Ping 360 project and to transport loads of up to 4.5 tonnes; it was used to move the bulkier construction materials, including the tower “heads”, into remote sites. The rescue trail A rescue trail, approximately 6km in length, runs generally along the cable car alignment, for use in the event of emergency evacuation from one of the cabins. The trail is constructed in difficult terrain, using timber (Fig 25) or natural stones. Close co-ordination with Maeda enabled a design to suit the construction constraints and with minimum impact on the environment of the country park. Fire engineering A drencher system between the two levels of each terminal building would normally be necessary to divide the large single compartment into two while also permitting cable car movement between the levels through a maintenance stair opening. This, however, would have required very large water tanks, with additional cost and space requirements, and would have impacted on the operation of the cable car. Arup provided a performance-based fire engineering approach to justify the deletion of this drencher system. A design fire was established to demonstrate whether there would be any smoke movement from level 1 to level 2 through the maintenance stair opening. The temperature and visibility of smoke spill to level 2 was also calculated. To limit the smoke spread from the lower level to the upper, a high level downstand around the lower floor opening was required, and it was also demonstrated that the downstand can prevent smoke spilling to the high level, using existing ventilation louvres for smoke outlets.
Page 1 and 2: 2 The Arup Journal 1/2008 Contents
Page 3 and 4: 4 Background Ngong Ping is an impor
Page 5 and 6: 6 7. Tung Chung terminal building a
Page 7 and 8: 8 11. Nei Lak Shan angle station an
Page 9: 10 The design of Tower 7 proved the
Page 13: 30. Ngong Ping Village. Conclusion

3 Ngong Ping 360 John Batchelor, Suresh Tank 15 Waste as ... - Arup

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