Submitted on: 18 May 1999.
Revised on: 28 June 1999.
Accepted on: 12 July 1999.
Proceedings of the Institution of Civil Engineers-Engineering and Computational Mechanics
Submitted on: 31 July 2009.
Revised on: 06 September 2009.
Accepted on: 01 October 2009.
NULL
Submitted on: 19 October 2018.
Revised on: 17 November 2018.
Accepted on: 28 November 2018.
NULL
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