China’s National Development and Reform Commission on Tuesday banned the construction of buildings taller than 500 meters (about 1640 feet) in the country amid concerns about the quality of some Chinese-built skyscrapers, Bloomberg reported on Wednesday.
“The outright ban covers buildings that are taller than 500 [meters],” China’s National Development and Reform Commission wrote in an official notice issued July 6.
“Construction of buildings exceeding 100 [meters] should strictly match the scale of the city where they will be located, along with its fire rescue capability,” the commission added.
Local Chinese Communist Party (CCP) authorities “will also need to strictly limit the building of towers that are more than 250 [meters] tall,” according to the statement.
The commission’s economic planner “cited quality problems and safety hazards in some developments stemming from loose oversight” as the reason for issuing the ban on tall buildings.
The order comes less than two months after the 355 meter-high (about 1,165 feet) SEG Plaza tower in China’s southeastern tech hub of Shenzhen shook on its foundation for unknown reasons on May 18, forcing hundreds of people to evacuate the 70-story building and its surrounding area. Chinese government officials have yet to determine the exact cause of SEG Plaza’s “wobbling” in May. An initial investigation into the incident proved inconclusive, the South China Morning Post reported on June 1.
“Investigators … have turned to vibration simulations to identify the cause of the mysterious trembling that shook the SEG Plaza, after a nearly two-week probe failed to explain it conclusively,” the Hong Kong-based newspaper reported.
“Vibration-excitation tests usually involve generators to simulate different vibration patterns to test a building’s integrity and identify parts causing resonance or that are the structural weak points,” according to the Post.
“Shenzhen government’s ambient vibration test or excitation test [are] to confirm whether the shaking episodes were a one-time ‘freak incident’ or if there were some ‘long-term dynamic processes in the building that can lead in the worst case to a collapse,'” Ulrich Kirchhoff, an associate professor at the University of Hong Kong Faculty of Architecture, told the Post on June 1.
The shaking of the tower is puzzling indeed. On that day of the incident there was not any typhoon, nor an earthquake. According to the initial investigation there is no damage to the structure … These tests ensure that no ambient or environmental force cause any structural effects in the building.
“The usual culprits for quality problems in skyscrapers [are] fast-track construction, a staggered design process – when construction starts while the architect is still designing – and the use of cheaper and inferior materials,” the architecture professor said.
“In a fast-track construction, the speed of floor-to-floor construction is rapid. In Hong Kong we take around five days per floor, four days with precast units,” Kirchoff said.
“Mainland [Chinese] media reports the SEG Plaza was built at a rate of 2.7 days per floor,” the Post revealed.
SEG Plaza’s owners have closed the tower pending a further probe into the incident, forcing the building’s tenants to find retail and office space elsewhere. The skyscraper was home to Shenzhen’s most popular electronics marketplace.
“[H]undreds of affected SEG Plaza shop and office owners have moved to nearby vacant premises in the Huaqiang north district,” the Post reported on June 1. The ousted tenants face a double financial burden of having to pay high rent rates for new temporary spaces while also experiencing a significant drop in sales after losing their prime marketplace location at SEG Plaza.