Tremor shakes parts of Bangladesh again

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Tremor shakes parts of Bangladesh
Published: November 27, 2021 19:38:14

A 4.2-magnitude earthquake shook different parts of the country including Chattogram on Saturday afternoon. The tremor was felt around 3:47 pm, according to the Bangladesh Meteorological Department (BMD).

The epicentre of the earthquake was in the India-Myanmar border region, about 308 kms South-East off Dhaka, the BMD said.

However, there was no report of any damage, injury and casualty by the tremor so far.
In the early hours of Friday, a strong 6.1 magnitude earthquake jolted Dhaka, Chattogram, Khulna and some other parts of the country. Its epicentre was at a depth of 32.8 kilometres (20.4 miles) near Hakha, Chin State, Myanmar, said the US Geological Survey (USGS).

At least three buildings tilted in Chattogram city following the earthquake on Friday morning, reports UNB.

 

[bluesky]

n the early hours of Friday, a strong 6.1 magnitude earthquake jolted Dhaka, Chattogram, Khulna and some other parts of the country. Its epicentre was at a depth of 32.8 kilometres (20.4 miles) near Hakha, Chin State, Myanmar, said the US Geological Survey (USGS).

At least three buildings tilted in Chattogram city following the earthquake on Friday morning, reports UNB.

6.1 is a big magnitude, no doubt. And three buildings have tilted. I haven't seen the photographs, but if it is a tilt it may mean two things:

1) The buildings are just our traditional brick-built buildings and the weak soil at one side caused that side to go under with the earthquake jolts.
2) The other is the structure is on the piled foundations, but the soil around the piles was unable to exert enough vertical friction resistance to keep them stable. In other words, the pile lengths, diameter or numbers were insufficient to withstand the vertical pressure due to earthquake.

Here comes the responsibility of Municipal engineering department. They sealed the design (I suspect, there was no stress analysis, as usual) without understanding the implication of an earthquake.

They probably even do not know that an earthquake has a vertical component also.