Discussion on Some Aspects of Structural Vibration by Mr. Pollard Digby
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Discussion on Some Aspects of Structural Vibration by Mr. Pollard Digby

The Structural Engineer
Discussion on Some Aspects of Structural Vibration by Mr. Pollard Digby
Date published

N/A

First published

N/A

Price

Standard: £9 + VAT
Members/Subscribers: Free

Buy Now

LT. COLONEL J. MITCHELL MONCRIEFF, C.B.E. (vice President) proposed a hearty vote of thanks to Mr. Digby for his extremely interesting and valuable paper. In the course of his remarks he recalled a conversation he had had with the late Sir Benjamin Baker in about 1896 or 1897, when the Central London Tube Railway was being built. Sir Benjamin had said that he had had the greatest difficulty with vibration: he had thought he had got the thing absolutely like a bed, but, when he went to his club some of his friends, who happened to live over the tube, wanted to know why their china was cracking and their pictures falling. That emphasised the great importance of vibration. Col. Moncrieff also recalled that some years ago he had heen concerned with the building of a chimney about 160 ft. high, and on one occasion happened to be on the platform at the top during a high storm. It was a weird experience to feel the chimney suddenly sway to one side, hesitate, and then come back to the other side, and so on. That was another form of vibration, however.

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Opinion Issue 12

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