To Kwa Wan collapse due to column damage Damage to a column caused by external forces may have triggered the collapse of the building at 45J Ma Tau Wai Road on January 29, according to a Buildings Department investigation report. According to Director of Buildings Au Choi-kai, the investigation focused on three collapsed columns situated on the ground level of the building (C11, C12 and C13). Based on the structurally asymmetrical design and respective estimated loading capacity of the three columns, as well as the information derived from further assessments, the department said column C13, which was affected and damaged by some external forces, may have caused the collapse. When column C13 was disturbed its loading capacity was reduced. As there was no provision of any precautionary measures at the site to share the load, the loading column C13 had to bear would have exceeded its capacity and the destructive effect spread to nearby columns C11 and C12, thereby increasing the loading on these two columns. Once the three structurally asymmetrical columns reached their ultimate failure state, they would have crushed progressively within a very short period of time, causing the lower portion of about two storeys of the building to collapse. The pull-down force so produced would have then caused the remaining upper portion of the building to collapse. The department concluded the collapse of the building at 45J was likely triggered by the disturbance of column C13 by external forces. Further investigations will be conducted to identify the origin of the forces.

Plan of the collapsed building showing the column layout. Source: BD

Universities test low-carbon lighting with Climate Group The Hong Kong University of Science & Technology (HKUST) and the University of Hong Kong (HKU) are helping the Climate Group launch an LED outdoor lighting pilot programme on their campuses. The pilot will see Hong Kong team up with ten other international cities including New York, London and Kolkata as part of the Climate Group's global LightSavers initiative. The programme will assess the potential of LEDs and smart controls to curb greenhouse gas emission and cut energy costs while making cities brighter and safer at night. The pilot project involves three sites at HKUST, HKU and Hong Kong International Airport. The four organisations will work together as partners over six to 12 months to test the performance of five different LED lighting products at these sites. Pilot results will be announced next spring. Globally, lighting accounts for 19% of the world's annual electricity use and nearly 10% (equivalent to 1.9 billion tons) of global CO2 emissions. The amount of emissions is roughly equivalent to that of 70% of the world's passenger cars, or 420 million vehicles. Lighting itself accounts for about US$19 billion in annual operating costs worldwide. Early trials of LED lighting have recorded energy-use reductions of 50-70% when paired with smart controls.

TD launches route search service The Transport Department (TD) has launched a pilot version of the driving route search service (DRSS) to help motorists plan their trips in advance through point-to-point route search on the Internet. The DRSS will suggest the driving route with the shortest travel time, the lowest toll and the shortest distance, along with a map. It also provides other information, such as no-stopping restrictions, vehicle restrictions, major carpark locations, as well as ad-hoc traffic arrangements, that may be related to the suggested route. According to assistant commissioner for transport (technical services) Tsang King-man, the travel time of the suggested route is an estimate based on previous statistics and the latest information collected by traffic detectors on roads, if applicable. The service is the department's first application of its intelligent road network (IRN) system, which provides regularly updated information to the DRSS. The pilot service can be accessed by going to www.drss.td.gov.hk.

New landslip prevention and mitigation programme The Government has launched a new landslip prevention and mitigation programme (LPMitP) to deal with both man-made slopes and natural hillsides with known hazards that are close to existing buildings and important transport corridors. The programme will dovetail with the existing landslip preventive measures programme (LPMP), which is due for completion this year following 33 years of work studying and upgrading man-made slopes. "Building on the achievement of the LPMP, the new LPMitP will systematically deal with both man-made slopes and natural hillsides in order to contain the overall landslide risk at a low level. We estimate that the annual expenditure on this new programme will be at least HK$600 million," said Secretary for Development Carrie Lam at the programme's launch. "The fact that over 1,000 landslides happened on natural hillsides during the severe rainstorm in Hong Kong on 7 June 2008 shows that the inclusion of natural hillsides in the new LPMitP is a right and forward-looking decision." The LPMitP will be implemented on a rolling basis annually to upgrade 150 government man-made slopes; conduct safety-screening studies on 100 private man-made slopes; and implement studies and necessary risk mitigation works for 30 natural hillside catchments.

Tenders invited for Central-Wan Chai Bypass The Highways Department is inviting tenders for the central interchange contract of the Central-Wan Chai Bypass project (Contract No HY/2009/18). The works mainly comprise construction of a 220 m section of tunnel in Central at the West Portal; an approach road, an at-grade slip road, a bridge deck for the westbound carriageway of Rumsey Street Flyover extension and an eastbound slip road flyover; plus widening of Man Yiu Street and associated road drainage works. The works are expected to commence in September 2010 for completion in January 2016. AECOM Asia Co Ltd has been appointed to design and supervise the construction works. The deadline for tender submission is noon on 25 June 2010.

WSD studies pumping optimisation The Water Supplies Department (WSD) has started a new project to investigate the optimisation of water supply pumping operations in order to save energy in the daily supply and distribution of water. According to assistant director of water supplies Bobby Ng, the project aims to apply a genetic algorithm, which is an evolutionary computing method based on trend data and projected demands, to generate operational parameters for achieving optimal real-time system control for water supply pumping operations. The algorithm works by evolving a set of solutions for a problem in a similar way to that of natural evolution. The solutions which are of a higher fitness will then be selected for refinement to achieve the optimal solution. An in-house project team comprising civil, electrical and mechanical engineers from the WSD has been formed to work on the optimisation project in collaboration with experts from overseas and local universities, institutions and consultants.

Winning design for Hong Kong Boundary Crossing Facilities Winning design for Hong Kong Boundary Crossing Facilities

The first prize of the Professional Group of the Hong Kong-Zhuhai-Macao Bridge (HZMB) Hong Kong Boundary Crossing Facilities (HKBCF) International Design Ideas Competition was won by "Under the Same Roof", a design submitted by a team comprising team leader Paul Mui Kui Chuen, Benny Lee Chiu Ming and Agnes Hung Oi Kee. HKBCF will be sited on an artificial island reclaimed from the open water off the northeast of Hong Kong International Airport and will be connected to the Tuen Mun-Chek Lap Kok Link, which is under planning. To cope with HZMB's construction schedule, the detailed design of reclamation works within Hong Kong territory and the ground investigation works started in September and December 2009 respectively. Detailed design of the HKBCF will begin soon. The competition received 160 entries from more than 20 countries and regions.

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