The main structure of Shanghai Tower, China's tallest building under construction, has been topped out

　　It is reported that the Shanghai World Financial Center, Jin Mao Tower, Xujiahui Center, Shanghai World Trade International Plaza... these are all skyscrapers in Shanghai. If you stand by the Huangpu River, you can see the modern urban landscape formed by these skyscrapers. However, these heights will soon be surpassed.

　　After five years of construction, China's tallest building, the 632-meter-tall Shanghai Tower, successfully completed its structural topping-out on June 5. It is expected that this super high-rise will open for business in the first half of 2015.

　　At 9:09 a.m., the steel beam for the structural topping-out of Shanghai Tower was hoisted, rising slowly and passing through the height nodes of the building.

　　125NG124H6—1 steel beam installation completed.

　　Master Wu Weiming, who has nearly 20 years of experience in tower crane operations for high-rise buildings, has been responsible for the hoisting work at Shanghai Tower for three years. Today, he was in charge of hoisting the last steel beam, which is of great significance to him.

　　Wu Weiming: I am very proud. After I finish this, I will soon retire. Today's last beam is also my last, a crowning achievement.

　　After the structural topping-out, the 580-meter steel platform will be dismantled, and structural compensation for the core tube and construction of the tower crown will be carried out. After that, dampers, cooling towers, and other equipment will be installed, and interior decoration will begin. For the builders, there are still many milestones to overcome.

　　By 2015, Shanghai Tower will become the last super high-rise building completed in Shanghai's Little Lujiazui area. Once in use, it will become a masterpiece integrating four communities: a vertical community, a green community, a smart community, and a cultural community.

　　Gu Jianping, General Manager of Shanghai Tower Construction and Development Co., Ltd.: We hope to provide higher-quality office or shopping spaces. In addition, we also hope that through the completion of this building, we can make some contributions to the improvement of the functions of the entire area and the city's skyline.

　　When many people look up at the high-rises springing up like bamboo shoots after rain and feel complacent, they ignore the ground beneath their feet silently subsiding. Land subsidence, an old topic that has never been truly taken seriously, has once again become a cause for concern as the Shanghai Tower, China's tallest building under construction, rises higher and higher.

　　In fact, not only in Shanghai, but more and more cities are joining the skyscraper club. When we look up at the tops of high-rises, have we also paid attention to the land beneath our feet? Can our cities really withstand the ever-rising high-rises?

　　The attribute of "city card" makes various cities eager to try their hand at building skyscrapers. The "2012 Skyscraper City Report" shows that mainland China has a total of 470 non-residential skyscrapers, with 332 under construction and 516 planned. It is estimated that by 2022, the total number of skyscrapers in China will reach 2.3 times that of the United States. Experts remind that skyscrapers do not win by "height," and high-rises do not necessarily represent modernization.

　　At present, more than 50 cities in China have suffered from land subsidence disasters, with the most serious in the Yangtze River Delta, the North China Plain, and the Fenwei Basin. Due to land subsidence, some cities are even predicted to disappear in a few decades. With ever-rising cities, continuously expanding usable space, and increasing water demand, how can we hold our horizon? Land subsidence has become an unbearable burden.

　　At the end of last year, many cracks appeared in the ground around the Shanghai Tower construction site, sparking discussions about whether the dense high-rises in Shanghai would cause land subsidence. Will Shanghai "go into the sea" because of the construction of a large number of high-rises? Tao Qingfa, Deputy Director of the Department of Geological Environment of the Ministry of Land and Resources, explained the cause of the subsidence at that time.

　　Tao Qingfa: The main issue at Shanghai Tower was the excavation of the foundation, which was quite deep. Due to dewatering, the groundwater lost its hydraulic head pressure, causing the surrounding ground to subside.

　　Of course, high-rises are only one of the causes of urban subsidence. Regarding how high-rise buildings can avoid similar subsidence during construction, Tao Qingfa, Deputy Director of the Department of Geological Environment of the Ministry of Land and Resources, also offered suggestions.

　　Tao Qingfa: In a city like Shanghai, high-rises can be built. During construction, all measures must keep up. Based on regional geological data, monitoring must be strengthened during production and construction, and groundwater drainage plans must be adjusted.