We demonstrate examples of beams with symmetric cross sections, loading and boundary conditions where, contrary to the engineer's intuition, slight perturbation of the symmetry (either in the cross section's geometry, or in the loading or boundary conditions) improves the overall structural response.
Three parameters were designed in the test, which are the recycled coarse aggregate (RCA) replacement ratio, the slenderness ratio and the cross-section loading method.
To reduce the computational costs in the 3D idealization, only half of the structure was modeled, which takes advantage of the symmetry of the railway cross section and loading pattern.
On the other hand, for TW2 with T-shaped cross section, the load-carrying capacity and initial stiffness were slightly overestimated under the negative loading in which the flange wall was in compression (see Fig. 5c).
The axial load (P u ) and magnified column moment (M c ) are then compared to the column cross section axial load-bending moment (P M) strength interaction diagram and if P u and M c fall inside of the cross section interaction diagram, the column meets the strength and slenderness requirements of ACI 318-11.
Quick information about the capacity of any cross section for combined loading is very useful information at the early stages of engineering design.
Cedolin et al. (2008) developed a method of calculating the design interaction diagram for rectangular cross section under biaxial loading based on the moment contour and Bresler Equations.
The smaller of the cross section pure axial load strength (P o ) and the column critical load strength (P c ) was used to establish the upper limit for the axial load levels to be used in determining the slender column strength interaction diagram.
The loading direction most critical for material failure is determined using a finite-element model of the blade cross section on which load combinations with different directions but with equal probability are applied.
The contact wire cross section under wind load is shown in Fig. 8.
This paper presents lateral buckling failures of laterally unrestrained steel cantilever roof of a tribune with slender cross section under snow load.
