Date of Award
Civil and Environmental Engineering
CC BY-NC-ND 4.0
The Canadian standard CAN/CSA-S37-M86 "Antennas, Towers and Antenna Supporting Structures" follows a quasi-limit states approach in which the member forces determined for specified loads are multiplied by a unified factor and compared against factored resistances given in CAN3-S16.1-M84. This results in a design basically the same as a working stress design with a factor of safety of 5/3. Due to the non-linear behaviour of the structure even under service loads, the non linearity in the load effect due to ice accretion on the towers, and the direct interaction between ice and wind loads, the load factors specified in CAN/CSA-S16.1-M89 "Limit States Design of Steel Structures" cannot be directly applied to antenna-supporting structures. In this study, forty-one different towers (representing different heights and designed for different ice classes and wind pressures) were analyzed under specified loads and then under a set of factored loads. From the comparison of the design forces in different parts of the towers with those calculated according to the existing standard, new proposed partial load factors for dead load, wind load and ice thickness are determined. A comparison between the design forces according to CAN/CSA-S37-M86 and forces obtained using the proposed load factors is included for all the towers. In addition, based on the analysis of climatic data, the wind pressure that can be applied to iced towers was determined and a change in the ice map of Canada given in CAN/CSA-S37-M86 is proposed. The proposed specified ice thicknesses were also verified under service loads.Dept. of Civil and Environmental Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1992 .W343. Source: Masters Abstracts International, Volume: 31-04, page: 1873. Thesis (M.A.Sc.)--University of Windsor (Canada), 1992.
Wahba, Yohanna M. Farid., "Limit states design of antenna towers." (1992). Electronic Theses and Dissertations. 2614.