Issue 2 2020 The Arup Journal Contents 4 Tai Kwun, Hong Kong 34 O ∙ PARK1, Hong Kong Preserving heritage in a busy metropolis By converting food waste into energy, Florence Lam, Andrew Lawrence, James this plant helps to create a healthier Sze, Paul Tsang, Young Wong, Gabriel future for Hong Kong Yam, Nina Yiu David Pegg, Michelle Shun 14 UNSW Science and Engineering 40 Harvey Milk Terminal 1, SFO, Building, Sydney, Australia San Francisco, USA Creating a world-class space for Sustainability was built into every step of science and the arts this major terminal expansion Rob Fleury, Ben Moore, Andrew Pettifer, Raj Daswani, Raphael Sperry, Stefan Sadokierski Byron Thurber 20 The Christie Proton Beam Therapy 48 Connswater Community Centre, Manchester, UK Greenway, Belfast, UK A safe and welcoming cancer treatment Providing flood protection while centre has patients foremost in mind every developing improved green spaces step of the way for the local community Nick Ashby, Hywyn Jones, Dave Pitman Carol Andrews, Chris Caves, Reuben Lucas 28 LocHal, Tilburg, Netherlands A once-empty former industrial space has been rejuvenated as a gathering place for the entire community Simone Collon, Rob Verhaegh, Babette Verheggen, Mathew Vola LocHal, Tilburg, Netherlands: Arjen Veldt Fotografie 2 2/2020 | The Arup Journal 3 TAI KWUN | HONG KONG Tai Kwun, the Centre for Heritage and of the site including structural, civil and Arts, is Hong Kong’s largest ever historic geotechnical engineering, and façade, building revitalisation project. Arup was lighting, fire, materials and security instrumental in transforming the city’s consultancy. Through seamless collaboration former Central Police Station compound, between Arup’s local team in Hong Kong and with its 170 years of history, into a new conservation experts from the London office, cultural centre. Refurbishment projects along with specialist conservation architect are not common in a city where land is Purcell and the local approval authorities, precious, with old buildings typically the unique historic buildings were demolished to make way for new successfully retained, repaired and developments. Standing in sharp contrast strengthened for adaptive reuse. to the surrounding commercial towers in the Central District, this revitalisation Material investigation provides a rare publicly accessible The Tai Kwun site is home to some of the ‘courtyard’ in the middle of one of the oldest surviving buildings in Hong Kong. densest cities in the world. Constructed using traditional Chinese materials (grey bricks and roof tiles) and Tai Kwun, or Big Station, was the materials imported from overseas (red bricks compound’s colloquial name and it was and timber), and using British building retained as a reminder of the site’s former techniques, it is an early example of the two usage and its historical importance. Led by cultures coming together. The Barrack Block The Hong Kong Jockey Club, in partnership was constructed in 1864, the Magistracy in with the Government of the Hong Kong 1914 and the Police Headquarters was built Special Administrative Region, the project five years later. The challenge for the project included the conservation of 16 buildings on team was to preserve the heritage buildings the site, which collectively form three on the 14,500m² site, making them accessible declared monuments (the former Central so they could be used for entirely new Police Station, the former Central Magistracy purposes and ensuring that they met modern and Victoria Prison), and the addition of two building standards. landmark buildings designed in collaboration with architects Herzog & de Meuron. With no record drawings or construction information about the existing buildings, Arup’s involvement in the project began in Arup’s team of structural engineers and 2007. The firm provided multidisciplinary material specialists conducted an initial engineering services for the transformation survey in 2009 to determine the structural 1. 1: Formerly Hong Kong’s Central Police Changing of the guard Station compound, Tai Kwun is now a centre for heritage and arts A Hong Kong landmark has been respectfully renovated and given a new lease of life and purpose 2: Tai Kwun’s Barrack Block was constructed in 1864. Police officers Authors Florence Lam, Andrew Lawrence, James Sze, Paul Tsang, Young Wong, Gabriel Yam and Nina Yiu were trained here 2. 4 2/2020 | The Arup Journal 5 TAI KWUN | HONG KONG 6: The hollow balustrade bottles were strengthened to comply with safety regulations by infilling with grout 7: The reinforced balustrades were load tested to code requirements 8: Arup designed steel arches to structurally enhance the historical brick archways 9: The steel arches provide minimal visual obstruction, showing only thin edges 6. 7. for the methods used to assess materials reflections that would destroy the integrity of for repair. Surface paint was removed and 3. 4. utilised in constructing historical structures the historical fabric. The solution was to damaged portions (due to dampness or in the city. The experience gained during the strengthen the hollow bottles by infilling termite activity) were replaced by timber form, condition and material strength. The requirements for the adaptive reuse of heritage Adaptive reuse project is being fed into the next edition of them with grout, doweling the infill at the top with an equivalent strength grade. Paint was firm worked with the Hong Kong Antiquities buildings in Hong Kong. As most of the existing structures were the Hong Kong Buildings Department’s into the existing granite copping and into the then applied for decoration and protection. and Monuments Office on agreeing the constructed prior to the development of Practice Guidebook for Adaptive Re-use and brick plinth at the bottom. Solid steel rods details of the opening-up works during During the investigation, an unusual type of building regulations, it was inevitable that Alteration and Addition Works to Heritage 22mm in diameter were added between the The timber floorboards were removed, these investigations. reinforcement was discovered within the Arup’s assessment approach would lead to Buildings, due to be released towards the end bottles and a 38mm-diameter solid steel top repaired where possible and returned to site concrete floor slabs in the Police Headquarters some structural enhancement in order to of 2020. rail installed. The system was load tested to for reinstallation, after which their surfaces Arup’s London office provided invaluable Block and the Central Magistracy: two meet modern design codes. The critical the current code requirements, allowing the were sanded and protective painting applied. advice on the properties and treatment of the 5mm-diameter wires were twisted into a mesh principle during restoration was to salvage Barrack Block upgrading works to gain statutory approval. The floors were upgraded to meet the historical materials such as brick, timber and within the concrete. At the material testing and reuse existing materials where feasible When first constructed, the 19th-century required one-hour fire resistance rating using cast iron. A rigorous procedure for the laboratory, samples of this twisted wire and, in line with the conservation Barrack Block had three storeys, with a Recycling timber elements fire-rated board, with the structural capacity material testing and data analysis was reinforcement were demonstrated to have management plan developed for the site, to further floor added in 1905. The block was Timber elements including doors, windows of the existing timber floor joists checked established, taking into account the buildings’ similar tensile strength to modern reinforcing minimise structural intervention as much as originally used as dormitories for the police; and floorboards were salvaged and reused using the British Standard for structural use heritage status. The number and locations of bars. Using a ‘first principles’ engineering possible. The methodology adopted meant in its new use as the visitor centre, which where possible. The door leafs and window of timber and verified by in-situ proof load the material samples taken for testing were approach, combined with statistical analysis that most of the building’s historical fabric, contains retail and restaurants, it has to casements were dismantled and sent off site tests. In retail areas, further steelwork was chosen carefully so that they would deliver of the test data and appropriate design factors, including granite blocks, floor tiles, accommodate increased loads. To avoid sufficient data for the statistical analysis while Arup proved the technical viability of reusing ironmongery, facing bricks, and timber overstressing the brick walls, the building minimising the damage to the building fabric. the existing slabs to avoid extensive doors, windows and floorboards, were was retrofitted with a steel frame constructed The data gathered was checked for statistical strengthening or recasting of the floor slabs. salvaged and reused. on new foundations. The floors and roof were outliers before being processed to deliver In the Police Headquarters Block, 80% of the strengthened to provide better restraint to the characteristic strength values for use in floor slabs were retained, with replacement Since refurbishment is not common in walls under wind loading. This approach assessment calculations. This is believed to be required in just two rooms – these were in Hong Kong, the collaboration with the allowed