Stress & Deflection Checks (Generic)
Requires: Advanced Level
VisualAnalysis can check stress and deflections levels in any member of any material or shape allowing you to check against any code or specification you require. You might also use this feature for fast preliminary checks. You can perform stress checks for axial, bending or combined stress limits you define. Limits may be different for tensile or compressive stresses. The stresses calculated by VisualAnalysis are based on the design load cases (ASD or LRFD). Deflections are checked against any specified deflection load combinations.
This type of check may be performed on tapered as well as prismatic members. Custom member shapes or specialized materials may be checked using this feature.
All forces and moments are assumed to act about the principal axes of the member's cross-section. Shear forces and torsional moments are simply ignored by this tool.
All stresses are based on the member's section z (strong) and y (weak) axes. Axial stress is defined as the average: axial force divided by cross sectional area. Bending stress is defined at the 'extreme fiber' as: the moment divided by the member's section modulus to the extreme fiber.
The locations of combined stress-checks on the cross section are typically the four extreme corners, but some shapes adjust these locations as shown in the picture below. For round shapes, the combined checks are at the top & bottom horizontal-center, and left & right vertical-center, rather than the four corners. meanging the bending from strong and weak axes are not combined directly. Tee shapes are also adjusted. Combined checks will simply fail on single angles, spandrels or zee shapes because the 'corners' don't exist! We recommend using IES ShapeBuilder for detailed investigation of stresses in complex cross sections.
Deflection Limit Options
See deflection limits in the essentials topic, as deflection checks are common among all material types.
Stress Limit Options
The, , , and fields allow setting of one of four options for checks of axial force stress, bending stresses from moments about the section-z axis, bending stresses from moments about the section-y axis, and combined axial stress plus both axis bending stress respectively. You may specify different limits for tension and compression for each type.
Hint: Positive numbers should be entered for your limits even though the VisualAnalysis sign convention uses negative values for compression forces and stresses. Using a very large limit effectively eliminates the check.
Generic Design Reports
Double-click on a member in a Design View to get a detailed report of exactly what was checked for a member (or all the members in a group).