防空洞 | Air-Raid Shelter
“重庆，是一座布满防空洞的城市 … 上上下下，密密麻麻，到处都是 … 当火锅跟防空洞结合的时候，就产生了重庆最大的特色 … ”杨庆导演2016年的电影《火锅英雄》给我们刻画了“洞子火锅”这一奇观式的餐饮空间。抗战期间，重庆军民挖掘了当时世界上最庞大的防空工程网，面积超过150万平方米。据陪都防空司令部的统计档案显示：1937年，重庆市共有防空避难设施54个，可容纳7208人，仅占重庆在册人口的1%。从1938年起，日本正式对重庆市区进行轰炸，国民政府随之加快防空工事的建设。至1942年，重庆防空洞数量已达1603个，平均每平方公里就有178个防空洞，基本可以容纳全部市民。
“Chongqing is a city full of air-raid shelters… When the hot pot is combined with the air-raid shelter, the biggest feature of Chongqing would be created…” The movie “Hot Pot Hero” has portrayed the spectacle-style dining space of “air-raid shelter hot pot”. During the Anti-Japanese War, Chongqing military and civilians excavated the world’s largest air defense engineering network, covering an area of more than 1.5 million square meters. According to the statistical archives of the Air Defense Command, in 1937, there were 54 air defense and shelter facilities in Chongqing, which could accommodate 7208 people, accounting for only 1% of the registered population in Chongqing. Since 1938, Japan officially bombed the urban area of Chongqing, and the National Government has accelerated the construction of air defense works. By 1942, the number of air-raid shelters in Chongqing had reached 1,603, with an average of 178 air-raid shelters per square kilometer, which could accommodate all citizens.
▼庭院及入口，the courtyard and the entrance
如今，山城巍然、洞口森森，但硝烟已散。重庆独特的“防空洞文化”开始融入百姓生活：在没有空调的年代，常年保持4℃的防空洞先是成了纳凉和幽会的圣地；随后，被当成异类的摇滚青年们也来了，带着乐器，吼着名副其实的“地下摇滚”；进入21世纪，市政府在修建轨道交通的时候，充分利用了原来的防空洞系统，并随之带动了更多公共功能的植入，有的被改造成了地下商场、火锅店、博物馆… 而那些小块头的则被改成了五金店、小卖部、社区纳凉点… 截止2019年，重庆主城区人防工程开发利用率已达到了91%。
Today, the mountain city and bomb shelters remain, but the fighting is over. Chongqing’s unique “air-raid culture” began to integrate into the people’s life: in the era of no air-conditioning, the 4°C air-raid shelter was sanctuaries for the cool and retreat; then, the rock-and-roll youths also came with musical instruments; entering the 21st century, the city government made full use of the original air-raid system when building rail transit, and then led to the implantation of more public functions. The air-raid shelters were transformed into underground shopping malls, hot pot restaurants, museums… while those small ones have been changed into hardware stores, canteens, community cool spots… By 2019, the utilization rate of civil air defense projects in Chongqing’s main urban area has reached 91%.
印制一厂 | Printing factory
The first and largest yard is the parking. The surrounding multi-story old factories have been stationed by various independent art studios. The mottled red brick walls are decorated with dazzling glass and black steel. The solemn revolutionary slogan paired with trendy graffiti and signboards, this is the atmosphere of a typical renovation project. Along the mountain road, it is the second narrow courtyard enclosed by two old staff quarters. They have been transformed into a gorgeous river view hotel named “Mountain Ghost”, which has not much nostalgia for its own historical identity. “He” proudly displays “his” superior “Face Score” in this slightly dilapidated old block. The north side of the hotel is the location of the project: the third courtyard enclosed by the old staff quarters, bomb shelter and former residences of the Sichuan military star Guo Xunqi. It has been redeveloped as a backyard of the “Mountain Ghost Hotel”. This project is a bar transformed from the original air-raid shelter in the 1st Printing factory in Chongqing. Chongqing has two Creative Parks transformed from the old factory area: the 1st printing factory in loquat mountain and the 2nd printing factory in ELing mountain. These sister factorys were built in the 1930s, unlike the 2nd printing factory that print the banknotes. The 1st factory has the temperament of books covered by dust. It once assumed the task of publishing textbooks and periodicals of the whole eastern part of Sichuan. The factory is located at the end of the Loquat Mountain Back Street. A total of eight buildings in the factory area are combined with three courtyards along the mountain.
庭院 | Yard
▼场地原状，existing conditions of the site
On the east side of the yard is the former residences of the Sichuan military star Guo Xunqi, which is a cultural relic-protected building built in 1934. The first floor of the old staff quarters on the south side has been transformed into the restaurant of the “Mountain Ghost Hotel”, which is also the main entrance to the backyard. The north side is three small air-raid shelters, but the easternmost one was blocked by the former residences of the Guo Xunqi. In the center of the yard is an old banyan tree with a canopy that fills the entire yard. Faced with such a small area, and the center is occupied by a huge tree pond, put the bar at the north end of the yard is almost the only choice, to make full use of the most characteristic elements in the courtyard.
▼改造后的场地，site after renovation
The three air-raid shelters are not connected to each other. Each floor space is about 4m*4m, and the arch is only 2.1m away from the ground. How to develop a space suitable for the bar is the focus of the design. Firstly, a 2.5-meter-wide front porch was added to connect the three air-raid shelters, but the plan is more like a series of cubicles connected by a corridor. To eliminate this state, we use a semi-circular desk to spatially “bridge” two of the air-raid holes, to make the bar plan become a radioactive space centered on an old stone wall, thus strengthening the overall sense. However, such a layout leads to smaller operation space, so the wine rack cannot be placed behind the bar as usual, but is placed at the end of the bomb shelter to form the background wall of the bar.
▼一条宽2.5米的前廊将三个防空洞串联起来，a 2.5-meter-wide front porch was added to connect the three air-raid shelters
▼中央被巨大树池所占据的院子，an old banyan tree with a canopy that fills the entire yard
1/4球体 | 1/4 Sphere
In order to connect the vaulted roof to the flat roof of the new front porch, we control the height of the front porch at the arched foot and use a 1/4 sphere to connect the wall, so as to realize the natural transition between the old and new parts in the external form and internal space, respectively. The main beam adopts 100mm*100mm C-shaped steel, and the other beams and columns are uniformly made of 50mm*40mm square steel pipe (the column is welded by five steel pipes into a cross column), which is the only small scale structural material in the nearby building materials market. The roof and the bottom of the roof are both 5mm thick galvanized steel sheets. The external drainage ditch is tilted outwards to ensure that the height of the cornice is only 35mm. The track of the folding sliding door is hidden in the C-shaped main beam to ensure that the continuity of the indoor and outdoor roof bottom is not interrupted by any member. The spheres that connect the flat roof and the vault are also perfectly presented indoors, but the inner wall material is replaced with mirror stainless steel, It re-projects the distorted image of the wine rack, making the indoor atmosphere more and more blurred and illusory.
▼衔接平屋顶与拱顶的球体，the spheres that connect the flat roof and the vault
▼拱顶以及球体屋顶，the vault and the spherical roof
▼半圆形的吧台将其中两个防空洞进行了空间上的“桥接”，a semi-circular desk to spatially “bridge” two of the air-raid holes
▼以一堵老石墙为轴心的放射性空间，a radioactive space centered on an old stone wall
▼内壁材料更换成了镜面不锈钢，它将背后酒架的残影扭曲、揉碎后重新投射出来，the inner wall material is replaced with mirror stainless steel, which re-projects the distorted image of the wine rack
Leader designer：HU Xing, LIU Changming, YU Kai
Technical design：LIU Changming，LU Baige
Interior design：COU Zongjie
Design team：XIAO Lei, WANG Zhizheng, GUI Fujian, LIU Chenyang, QIAN Man, CHEN Yumo
Design: Qing Studio
Design/Completed: Oct. 2019
Location：Yuzhong District, Chongqing
Gross built area: 108㎡
Owner：Shangui (chongqing) hotel management co. LTD