Date of Award


Degree Type


Degree Name



Civil and Environmental Engineering


Engineering, Civil.




Latticed triangular-base steel towers have been used as communication structures for a long time. Since these triangular-base towers are economical, they are also being increasingly used as electrical transmission line towers. The legs of these towers generally consist of 60$\sp\circ$ equal leg angles (either 90$\sp\circ$ rolled angles bent to 60$\sp\circ$ or rolled 60$\sp\circ$ angles) which are primarily compression members. Results of experimental investigation on eighteen equal-leg schifflerized angles (90$\sp\circ$ angles bent to 60$\sp\circ$) under concentric axial compressive loading with hinge-hinge end conditions are presented. Five sizes of angles viz. 5 x 5 x 5/16, 4 x 4 x 1/4, 3$1\over2$ x 3$1\over2$ x 4/16, 3 x 3 x 3/8, 3 x 3 x 1/4 in., of 300 and 400 MPa nominal yield strength with slenderness ratios varying between 50 and 95 are included in the investigation. The nominal width-thickness ratios of legs ranged between 8 and 16. The experimental failure loads are compared with loads obtained from a finite element model. The analytical problem has been solved for failure loads under geometric and material nonlinearity. A Newtonian approach with eight-node shell elements has been employed for the nonlinear solution using commercially available software "ABAQUS". Residual stress variations along the cross-section and through-the-thickness are included. All results are compared with those obtained from CAN/CSA-S37-M86, ASCE Manual No. 52 and other specifications. The value of the flat width to be used in the width-thickness ratio calculations is discussed and recommendations are made.Dept. of Civil and Environmental Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1990 .A358. Source: Masters Abstracts International, Volume: 30-03, page: 0815. Thesis (M.A.Sc.)--University of Windsor (Canada), 1990.