HÀ NỘI – Three high-rise buildings near Lương Yên Bus Station in Hà Nội were not affected by recent tremors after a 5.3-magnitude earthquake that struck China on Saturday morning, according to local authorities.

Chairman of Hai Bà Trưng District’s People’s Committee Vũ Đại Phong said the three buildings shook on Saturday morning, causing panic for hundreds of construction workers.

Many fled into the street when the tremors started, with rumours circulating that the buildings had started tilting and are at risk of collapse.

Phong said the committee, together with city authorities, had conducted a quick inspection on the buildings and found that the buildings were safe.

He said the authorised agencies were conducting further inspections and would announce the results soon.

The 5.3 magnitude earthquake hit China’s Yunnan Province, around 118 kilometres to the north of Mường Tè District in the northern mountainous province of Lai Châu, the Institute of Geophysics said.

Tremors were felt at some high-rise buildings in Hà Nội, including the 26-storey buildings on Lương Yên Street.

Nguyễn Duy Bình, a worker on one of the buildings, told dantri.com.vn that he was on the sixth floor when he felt the structure shake for two minutes.

Bình said he thought he was suffering from high blood pressure until he heard people shouting to flee the building.

A representative from the city’s Department of Construction said the department has sent inspectors to the scene and found the buildings were safe.

Warnings from experts

Dr Trần Chủng, former director of the Ministry of Construction’s Department of State Agency for Construction Quality Inspection told Vietnam News Agency that the tremors did not cause any cracks on the buildings and electric networks were still operational.

However, he said the State management agencies needed to conduct surveys to find and evaluate cracks on high-risk buildings.

The management board of high-rise buildings in the city must educate people about the risk of earthquakes.

He also added that the State management agencies must consider geological factors in the placement of high-rise buildings.

The construction of a high-rise building that could resist different levels of earthquakes could be costly. Thus, projects built in earthquake-prone locations must be moved to safer places or have funds for earthquake resistant structures.

The construction design must depend on the geological conditions of the location. If the construction work is in an earthquake-prone area, it must be designed according to the earthquake strength, Chủng said.

According to Chủng, Việt Nam is not located in the Pacific ‘Ring of Fire’, so earthquakes are normally at a medium magnitude of between seven and eight.

PhD Phạm Sỹ Liên, vice chairman of Việt Nam Construction Association said Việt Nam has different earthquake-prone areas and Hà Nội is in the earthquake area of level 7, according to the earthquake classification table of the Institute of Geophysics.

Therefore, all high-rise buildings must have designs sufficiently resistant to magnitude eight earthquakes. This is the responsibility of the state management agencies when reviewing design dossiers of assessment work for high-rise projects. – VNS