(Yicai Global) Jan. 7 -- The mysterious trembling of Seg Plaza, that resulted in the 23-year-old skyscraper in the hi-tech hub of Shenzhen being closed for months, has cost its property management company Shenzhen Seg, which also owns just over a quarter of the tower, a direct hit of CNY55 million (USD8.6 million).

This is the bill for emergency rescue works carried out when the structure started to vibrate last May, Shenzhen Seg said, without giving a breakdown of the amount nor saying whether the company was insured.

The bill has wiped out the firm’s entire profit over the first three quarters which came to CNY53.5 million, according to its latest earnings results.

Office workers were filmed fleeing Seg Plaza on May 18, when the 79-storey building started to vibrate greatly. There was no sign of an earthquake, but the wind was strong, reaching Grade-5 on the Beaufort scale. The tremors continued on May 19 and 90 percent of businesses were forced to move out.

Subsequent investigations revealed that the masts, which serve to protect the skyscraper from lightening and as a navigation marker, had cumulative damage after over 20 years of use, causing them to resonate under certain wind conditions. The posts were removed and alternate structures put in their place. The building reopened fully on Sept. 8 last year.

Seg Plaza, which is located in the heart of the country’s biggest electronics markets, was built in 1999 and remains the world’s tallest building made from concrete-filled steel tubular columns. Shenzhen Seg owns 39,900 square meters of the building, out of a total floor area of 170,000 sqm. The rest is owned by Shenzhen Seg’s parent firm Shenzhen Electronics Group.

Shenzhen Seg’s share price [SHE:000058] closed down 4.63 percent at CNY6.39 (USD1) apiece today.

Editor: Kim Taylor