WallaceLiu設計事務所（地緣營造）

1 改建前的高速公路（中段，2014年3月）The highway before transformation(middle section), March 2014

2 改建后的高速公路（中段， 2017年7月）The highway after transformation (middle section), July 2017

3 改建前后道路中段的平面圖Before and after plan in middle section of the street

位于倫敦的設計工作室WallaceLiu將中國西南部城市重慶的一條長1 km、寬20 m的高速公路改造成一條開放共享的“宜居街道”。設計的核心是打破一般城市公路的單一、線性的構圖特征，以非線性的、開放的公共空間尺度和格局取而代之。對城市、業(yè)主和設計師而言，項目提供了一個探索中國為促進快速發(fā)展而建的基礎設施如何轉化以培育新興城市文化的機會。

項目基地所在的燕南大道區(qū)域是中國當代城市發(fā)展的典型邊緣地帶，隨著城市的擴張而改變了其土地性質。隨著開發(fā)商北大資源的介入，大道沿線的7個地塊將承載大片的高密度住宅。這條道路將貫穿近20 000 m2的新開發(fā)的沿街商業(yè)，在服務新住宅區(qū)同時也要繼續(xù)服務現(xiàn)存的幾棟低保住宅。

項目所涉及的燕南大道，其原有公路在建造過程中發(fā)現(xiàn)有兩處電塔陡坎與公路的規(guī)劃路徑有沖突。由于移除電塔及陡坎的經(jīng)濟代價太大，建成后的公路有兩處陡坎在中途插入占用兩車道形成了兩處不安全的收縮點。收縮位置往來使機動車駕駛員視線變差，人行道更是出現(xiàn)中途斷頭路，人行過路交通在這些部位陷入機動車盲區(qū)。拿到初步開發(fā)許可后，開發(fā)商開始擔心公路現(xiàn)有的狀況不僅有明顯的安全問題，如此大尺度的道路也會對未來道路兩側的商家入駐帶來不利，難以營造適合行人停留的餐飲、休憩的街道氛圍。

WallaceLiu設計事務所在2014年通過競賽中標取得該項目。參賽期間提出的設計思路是用把整體道路降級為兩車道（與陡坎處同寬）的辦法，來解決陡坎帶來的安全隱患問題。事務所認為“利用現(xiàn)狀問題帶來的契機對道路進行整體降級，實則是提升整個街區(qū)城市生活質量的好機會。對于‘降級’后是否會帶來交通擁堵的問題及其他的疑點，可以用臨時搭建來擴大人行范圍，測試后再整體實施”。然而這種“整體量變”的做法引起了當?shù)匾?guī)劃和交通部門的擔憂，沒有獲準通過。1年后，得益于開發(fā)商的堅持，事務所重新提出的“整體共享鋪裝”的做法獲得了當?shù)卣恼J可。

4 在改建后的公園中散步（2017年7月）Walking down the transformed park, July 2017

5 公園中非正式的座椅Informal seating in the park

整體共享鋪裝，作為一個城市公共空間的類型，旨在削減機動車交通在街區(qū)規(guī)劃中的主導地位。模糊了實際道路與周圍公園綠地、廣場、口袋空間及其他城市休憩設施之間的界限?！拔覀兿氚颜麠l公路沿線改造成一個適合步行和玩耍的地方?！?/p>

由公路系統(tǒng)主導建立的城市景觀，其主要問題在于不斷強化一種線性的、隔斷性的街道剖面，這種剖面主要滿足機動車的流速。路緣石、道路劃線、交通標識、人行護欄、嚴密的行道樹、人行與沿街公園之間的綠籬等，都是機動車主導街道剖面的組成要素。因此，通過移除或弱化這些要素，并全面對鋪裝、城市家具、種植的布局進行調整，就可以打破原有公路的印象，以一個獨具特色、充滿生氣的開放式漫步道取而代之。人車共享空間的效用在于從心理上引導機動車輛因為視覺障礙增加而小心緩行通過，以及鼓勵人行在多角度穿越街道。

實現(xiàn)這個設想的具體措施包括在機動車道上整體鋪設呼應銀杏色彩的暖色調的小塊混鋪花崗巖，并把這個材料做法和紋理延續(xù)到人行區(qū)域。設計用石材鋪裝的圖案取代了傳統(tǒng)的道路劃線，用新的沿街排水渠來過渡人行道和車行道的高差，削弱了道路原有的路牙特征。這些做法讓設計師得以保留現(xiàn)有基礎設施的排水系統(tǒng)，并大大降低新工程的成本。在兩個陡崖附近，設計師設計了更平滑的彎道，用大量的鑿面花崗巖鋪路石形成凹凸不平的減速帶，提醒車輛在通過此區(qū)域時減速慢行。

6 公園中彩色的有機玻璃景觀廊架Coloured canopy installed in the park

7 有機玻璃景觀廊架細節(jié)Detail of coloured canopy

“因為不能縮減原有車道的實際寬度，只能從整體設計上通過調整周邊環(huán)境與道路之間的比例關系，使視覺上機動車道的主導地位消失。因此設計師有意擴大新景觀元素的尺度，如公共長椅、公園綠地的漫步道、口袋廣場等，幫助車輛和行人對整個區(qū)域建立新的印象—一個整體開放的城市慢生活街道的印象?！?/p>

街道中段是這個改造項目的核心區(qū)域。WallaceLiu認為這一段應該是“最能體現(xiàn)綠色慢生活的一段”。設計師在這一段道路的東側利用現(xiàn)有的成年樹木，布置了一個開放式的以漫步道為主線的街邊公園。公園的南端是一處公共兒童活動場。與一般的硬化標準兒童活動場地不同，這個活動場通過塑造高低起伏的綠地，為攀爬、滑動和富有想象力的游戲創(chuàng)造了墻壁和斜坡，并營造了兒童在自然中玩耍的印象。公園對面放置了一組大型種植池和座椅，用類似的植被和設計語言創(chuàng)造了一個鏡面式的綠色空間，將道路設置在這個綠色長廊的中心。

為了強化上述景觀特色，突出空間的統(tǒng)一性，并進一步模糊車行道和人行道的邊界，設計者使用了3種常用的花崗巖材料，為所有鋪裝區(qū)域提供溫暖的色調。不同顏色的組合設計以搭配現(xiàn)狀沿路種植的銀杏樹的金色樹冠。工程經(jīng)驗告訴設計者，在路面上設計大型的圖案會使得高質量的建設實現(xiàn)起來較為困難，同時也無法創(chuàng)造出設計者構想中的平靜氛圍，所以設計者對此進行規(guī)避。相反，設計者將4種不同的花崗巖組合起來，鋪設成15 m的面板，并安置在場地不同區(qū)域中。通過改變毛邊尺寸、表面處理、接縫寬度和每種材料的比例，來體現(xiàn)鋪路紋理的細微差別。為了柔化公園里和沿路邊的種植池與硬質路面鋪裝交界處的邊緣，設計者采用了黏合與松散的兩種礫石以構成一種視覺上軟化的適宜停留的舒適地面。

道路原有的沿街銀杏樹，在保留下來后通過增加和穿插其他種類的成年樹種，從行道樹變成開放公園的一部分，并成為人們在重慶酷暑天氣能夠繼續(xù)街道生活的基本要素。除此之外，工作室還設計了一組用吊掛彩色有機玻璃板構成的天篷，這些玻璃板在日光下將其豐富的色彩投射到地面和草皮上，成為復雜而生動的自然陰影。這樣做的初衷是調節(jié)改善周邊塔樓、城市背景和時而灰霾天氣帶來的壓抑的灰色調。

在關鍵的開放空間，布置一組大尺度的預制鋼木座凳，這些座凳的樣式是可坐可爬的“波浪”平臺?？梢杂糜诖笮突蛐⌒途蹠?，吸引兒童在上面玩耍，同時它們還充當了新心理信號，提醒司機路過時注意減速。小號的座凳大多集中在公園綠地，以提供給更需要安靜的個人使用。這套城市座凳對細節(jié)的要求較高，由場外加工完成，硬木的規(guī)格及它們的建造質量都非常高。設計師專門向客戶說明不要在木材上涂清漆，而是使用自然木油或木臘，允許在保護木材免受風化的同時自然灰化。

另一個得以實現(xiàn)的設計想法，是在種植上選擇野生花卉和季節(jié)性灌木。季節(jié)性灌木景觀在枯季會顯得荒蕪，因此在中國當代景觀設計中很少使用。該項目的業(yè)主非常支持這種設計手法，并幫助設計師在本地尋找到成都的供應商。與供應商建立合作關系后，設計師能夠根據(jù)本地的品種和庫存情況，結合現(xiàn)場的布局進行品種組合和季節(jié)搭配，篩選有限但可實現(xiàn)的品種對最終的效果至關重要。

改造工程于2015年夏天動工，中段的全部、部分北部和南部區(qū)域在2017年夏天完成，整體在2018年竣工。這個項目中最重要的設計決策是注重公共空間的建成質量和用戶體驗，而不是創(chuàng)建一處符號性與圖案性的物質景觀。這條道路現(xiàn)已重新開放，并更名為新九龍步行街。

（編輯/祖笑艷）

8設置在保留大樹中的一組下沉游樂區(qū)，前景為原木坐凳Sunken play area set in retained mature trees with logbench in the foreground

9周邊居民在公園中自發(fā)形成的聚會（2017年7月）Informal meetings of neighbours in the park, July 2017

10穿越公園的漫步道The promenade through the park

設計公司：WallaceLiu 設計事務所 （地緣營造）

網(wǎng)站：www.wallaceliu.com

項目區(qū)位：中國重慶

業(yè)主：北大資源集團重慶分公司

項目類別：公共空間

竣工時間：2018年

設計團隊：劉婕，Jamie Wallace，崔漫舒，徐蘇莫

攝影：WallaceLiu 設計事務所（地緣營造）

翻譯：錢蕾西

校對：孫越

11 波浪狀起伏的長凳Long undulating benches

12 景觀廊架投射的彩色光影Coloured shadows cast by the canopies

13 有景觀廊架和座椅的、大廣場一樣的空間A larger plaza-like space with canopy and seating

14 街道上高大的成熟樹木Large mature trees in the street

London based design studio WallaceLiu have re-imagined a 20 m wide, 1 km long highway in the South Western Chinese city of Chongqing as a shared surface “l(fā)ivable street” by replacing the delineation and monolithic character of the highway with the language and scale of a public space. For the city, the client and ourselves the designers, the project provided an opportunity to explore how China’s infrastructure, built to facilitate rapid growth, can be post-rationalized to nurture an emerging urban culture.

The site represents the typical periphery of a modern Chinese city that has changed its land use as the city expands. The highway, Yannan Avenue,along which 7 large plots of land were purchased by the state-owned developer PKU Resource, will become the new route through nearly 20,000 msq of street retail and high-density residential compounds and adjacent to existing low-income social housing.

During the construction of the original highway, it was decided on site that two electricity pylons and the cliff they sat on are interfering the route of the highway, but too costly to remove.As the highway was at an elevation well below the pylons the impact of this was huge, resulting in two cliffs that interrupt the highway, creating unsafe pinch points, poor visibility for drivers and pavements with dead ends. After the development received outline development permit, the developer was concerned that the highway will provide neither a safe and pleasant environment for the new community nor a good shopping and eating atmosphere for the large amounts of upcoming retailers.

WallaceLiu won the project in 2014 through a competition with an initial idea that the safety issues created by the cliffs could be used to argue that the highway width in its entirety could be reduced to two lanes, to match the width at the pinch points.“By resolving these awkward accidental problems”,WallaceLiu argued, “we could change the whole space for the better”. The proposal included temporary solutions to trial the “downgrade” and its impact on traffic and pedestrian behaviour, then,through time, to complete the permanent new kerbs and pavement extensions as funding became available. This however raised tension and concern in the local planning and transport department therefore was not approved. A year later, with the support of the client, we managed to secure support for a shared surface design where we paved over the highway instead.

The shared surface, as a typology of public space, aims to remove the dominance of vehicles.It provides a blurred boundary between the actual road and its surrounding parks, plaza, compounds and other urban facilities. “We imagined the entire highway to be transformed into a walkable and playful place.”

The symptom of a highway dominated urban landscape is strengthened delineation based on an extruded street section, which serves the speed of passing traffic only. Kerbstone, road markings,traffic signage, pedestrian fences, perfectly ordered street trees, hedge boundaries and limited pedestrian crossings, are all elements of this car dominated landscape. By removing these elements and designing the paving, furniture and planting to work holistically, the delineated highway is remade as a characterful and vibrant open promenade.Pedestrians are encouraged to cross and use the street at their convenience and drivers must be more aware of the people at any moment therefore slowing down as they travel through the space.

The resolution of the idea was made through the paving of the highway with a new granite surface, the repaving of pedestrian areas with a similar material, the removal of pedestrian barriers and most signage including road markings and the introduction of a new type of kerbstone that was flush with highway and pavement. Through careful design of the new street levels we were able to retain the existing sub-base and drainage therefore significantly reducing the cost of the new work.Around the two cliffs special safety measures were introduced in the form of smoother turning circles and “cropped” granite setts that create a bump when driven over.

“Because the width of the carriageway could not be reduced, we had to engage with its scale through design to remove its visual dominance. We did this by enlarging the new landscape elements such as public benches and planters, the main path through the park and the width of pocket squares to radically alter the visual proportion and impression of the overall place as one walks down the street.”

The middle section of the street is the most significant part of the change where the existing street park on one side adopted an entire new geometry of paths whilst keeping existing mature trees. An informal and unfenced public playground was created at the southern end of the park by digging into the landscape to create walls and slopes for climbing, sliding and imaginative games.A set of large planters and seating was placed opposite the park creating a mirrored green space in a consistent language, therefore locating the highway at the centre of a green promenade.

To strengthen the character, emphasise the idea that this is a single place and further blur the boundaries of the road and pavements we used three types of commonly available granite to render a warm tone to all paved areas. The colour mix is chosen to compliment the intense golden canopies of the existing gingko trees along the avenue. We avoided using large patterns in the surface as our research suggested it was difficult to achieve a high build quality and it would not create the calm atmosphere we wanted to create.Instead, we designed four different mixes of granites laid out as 15 m panels which were then located in different parts of the site. By altering the coursing dimension, the finish, the joint width and the proportion of each type to introduce subtle differences in the paving texture. To soften the edges of the hard paving where it meets planting in the park or planters along the street, we used both bonded gravels and loose gravels to achieve a relaxed ground cover for siting and gathering.

The existing gingko trees were to be become part of the open park and offer shade alongside newly added mature trees to encourage people use the street in the extreme hot summer of Chongqing. We also designed a series of coloured canopies to help lift the generally grey tone of surrounding towers, framing and filtering views at significant stopping places in the street. They are made with hanging perspex panels mimicking coloured clouds over a pebble-grey coated steel structure to cast complex and vivid shadows on the ground.

Other key design elements include a set of off-site manufactured steel-timber furniture. This seating is designed to form a “wave” of sit-able and climbable decks that can be used for large or small gatherings and that encourage children to play on them. They also act as new psychological signals for traffic to slow down as they pass by.Smaller seats are mostly clustered around the park for calmer individual use. The build quality of these seats is very high due to its off-site production and the specification of the hardwood. We purposely convinced the client to not apply a glossy paint over the timber, so the varnish can show the beautiful natural aging whilst protecting the wood against weathering.

Another design choice that was realised was our choice to plant wild flowers, perennials and shrubs. They are very rarely used in Chinese contemporary landscape design due to their deciduous nature. Our client was supportive of the approach and helped us find suppliers in Chengdu who we then worked with to understand their available stock and begin to apply these in complex compositions across the site.

The project started on site summer 2015 and the whole middle section and part of the northern and southern sections were completed in summer 2017，and overall completion is scheduled in 2018. The most significant design decision was to place an emphasis on the build quality and user experience of the public space rather than to create a symbolic, object and pattern based landscape. The street has now reopened and has been rebranded as the New Kowloon district.