Buy article PDF
Instant access to
the full article PDF
for the next 48 hrs
US$ 35
|
Wind and Structures Volume 1, Number 2, June 1998, pages 183-199 DOI: http://dx.doi.org/10.12989/was.1998.1.2.183 |
|
|
|
Field measurements of wind-induced transmission tower foundation loads |
||
E. Savory, G.A.R. Parke, P. Disney, N. Toy and M. Zeinoddini
|
||
| Abstract | ||
| This paper discusses some of the findings arising from long-term monitoring of the wind effects on a transmission tower located on an exposed site in South-West England. Site wind speeds have been measured, together with the foundation loads, at the base of each of the four legs. The results show good correlation between the wind speeds and leg strains (loads) for a given wind direction, as expected, for wind speeds in excess of 10m/s. Comparisons between the measured strains and those determined from the UK Code of Practice for lattice towers (BS8100), for the same wind speed and direction, show that the Code over-estimates most of the measured foundation loads by a moderate amount of about 14% at the higher wind speeds. This tends to confirm the validity of the Code for assessing design foundation loads. A finite element analysis model has been used to examine the dynamic behaviour of the tower and conductor system. This shows that, in the absence of the conductor, the tower alone has similar natural frequencies of approximately 2.2Hz in the both the first(transversal) and second (longitudinal) modes, whilst for the complete system and conductor oscillations dominate, giving similar frequencies of approximately 0.1 Hz for both the first and second modes. | ||
| Key Words | ||
| transmission tower; wind loading; meteorology; structural analysis. | ||
| Address | ||
| Department of Civil Engineering, University of Surrey, Guildford GU2 5XH, U.K. | ||