The tower began to shake at around 1 pm on 18 May
Real-time monitoring of the building’s vibration frequency, tilt rate and settlement degree found that they did not exceed official safety parameters
Merchants were allowed to enter the SEG Electronics Market on Wednesday, but customers were still being denied entry
The Shenzhen housing and construction bureau commissioned multiple professional institutions to conduct real-time monitoring of the building’s vibration frequency, tilt rate and settlement degree from 9pm on May 18 to 3pm on May 19, and found them all to be within official ranges set by China’s safety bodies, according to the statement released on the official WeChat account of the Shenzhen government.
a preliminary investigation indicated that a combination of three factors, including wind, the subway line below the SEG Plaza, and temperature differences inside and outside the building, likely all played a part in what some experts have said was the creation of an aerodynamic phenomenon known as the “Karman vortex street”, according to a report from the state-backed China Securities Journal.???
Humen bridge swings in 2020
the shake has happened for past 3 days.
so far it is still investigation.
archtectural structure design:
当年最先进钢混结构 ( 鋼管 + 混凝土填充)
冯果川指出,这种技术在当时的年代,在操作层面依然存在一定难度。因为混凝土要被震荡、灌注得非常密实,才能充分发挥其抗压能力。如果震荡得不够,有可能会产生“空腔”,倘若真的有,那么便会产生问题。“就算真的存在较小的空腔,一般也不会影响到整个大楼的安全性。具体是否存在空腔,还需要等待专家的检测结果。”
从2013年2月至2015年底,政府曾将华强北路整个路段进行围挡封路,以让“三横一竖”四条地铁线都直接经过华强北,并建造大型地下商场,将整个华强北路段改造成了步行街。
from a research paper of 金典琦
possible reasons
Yes:
事后披露的调查情况显示,赛格大厦未安装阻尼器 tuned mass damper
No:
Tidal effects on gravitational pull
Earthquake
Strong winds
underground trains pass by???
all these are not at maximum during this period.
Maybe:
temperature changes. usually happens at 1 pm. hottest time of the day, causing uneven thermal expansions.
Ageing
uncertain:
is it using a vertical damper? It was mentioned the wobble direction is vertical
在到處都是高樓大廈的香港地下同樣佈滿地鐵線路,為何沒有發生類似事件?陳健碩指出香港其實也有類似情況,以已結業的香港麗嘉酒店為例,「我以前在裡面吃飯,有幾層地牢,地鐵一經過,我也感覺到震動。最重要它在震動過程中仍然處於彈力區,沒有破壞結構就可以。」
他強調所有樓房只要受到外來影響,都會震動,只是設計要求盡量做到震幅不是有感震動。研究賽格大廈的碩士論文亦曾提及大廈在建成初期,因計算錯誤造成共振,天線已經不停搖擺而要緊急維修,由此可推論大廈可能自建成起,就一直有震動,只是以住都是無感震動。「這次造成有感震動,其實是頗嚴重的了,需要作出調查。」
Wenweipo
hkcnews.
citigroup center in NYC
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