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Latticed towers of telecommunication are very vulnerable structures under wind loads essentially if these loads are due to wind forces from hurricanes. A number of 59 towers collapsed or partially failed from 1996 to 2012 in Cuba under wind action forces. A study of failures confirmed that many of them supported various antennas. Towers were designed to support a little number of antennas however; communication development generated an increase of antennas on the existing structures with a modification of the structural behavior. The aim of this work is to assess the effect of antennas disposition on many structural parameters as displacement, stress on member and frequency of the tower by means of a numerical experiment.

Self-supporting lattice towers are slender structures with low damping and high flexibility. They are sensitive to dynamic loads such as wind and earthquake. In the West of Cuba, structures should be analyzed under extreme winds and seismic effects, which raised their frequency during 2010 year. Self-supporting towers do not have the same dynamic behavior as buildings under seismic loads. Their specific structure features are not developed at design seismic codes, for that reason it is necessary to study methods of seismic analysis for self-supporting towers. The methods selected in this research are Modal Analysis Method proposed by Cuban Seismic Code (NC-46:1999) and modal superposition lineal dynamic analysis named Time History. It was selected for the study two self-supporting towers designed in Cuba, Versalles Model (3-legged) and Najasa Model (4-legged). Comparative analysis between both methods is realized with extreme values of internal forces at element towers.

Guyed masts are a specialized type of structure commonly used in the broadcasting industry to support equipment at substantial heights. Surprisingly, the failure rate of this structural typology with respect to others of similar complexity is high. Therefore, this study searches for the reason behind the failure of telecommunication towers under extreme wind action, which does so by making a comparison between qualitative analysis and the physical –mathematic computational models of the failed towers. The results of the physical- mathematic models are obtained by means of a non – lineal geometric analysis of the structures. Results are then discussed after which are used to outline the importance of both studies as a means of validating results