FAILURE ANALYSIS OF THREE-LEGGED GUYED TELECOMMUNICATION MAST IN CALABAR AND MINNA, NIGERIA.

Abstract

Two cases of telecommunication mast collapse in Calabar and Minna, Nigeria were considered for structural integrity audit to ascertain all the likely causes of the tower collapse. A Collapsed 30 metres three-legged guyed telecommunication mast, by University of Calabar Teaching Hospital, Calabar and a 20 metres three-legged guyed telecommunication mast at Tunga roundabout by David’s road, Minna, Niger State, Nigeria was investigated. A typical 30 metres and 20 metres guyed mast of pipe section for the main pole and solid-round high tensile steel for bracing was modelled, analysed and designed using STAAD-Pro V8i software and loadings applicable to Calabar and Minna environment respectively. The result showed that the 30 metres three-legged guyed telecommunication mast, by University of Calabar Teaching Hospital, Calabar and a 20 metres three-legged guyed telecommunication at Tunga roundabout by David’s road, Minna, Niger State, Nigeria, collapsed due to insufficient depth of the footing for the guy wires as the mast themselves could not withstand the wind pressure and inadequate sections provided. There was no sufficient space for the guy wire anchorage. It was recommended from the study that; more attention should be paid to guy wire footing. The depth of the guy wires for the collapsed mast was 600mm and the minimum from this research is recommended to be 1200mm for any mast above 15 metres tall. More so, Proper analysis should be carried out on the guy wire in order to determine the initial tension value during guyed mast modelled, analysis and design. While sufficient space should be provided for guy wire anchorage.