When the Graphs Don’t Match: Understanding the Controlling Case A common question from users is why the maximum moment shown in the Detail Report graphs doesn’t match the required flexural moment reported in the design results. At first glance, this difference can be confusing — but it comes down...
Rigid diaphragms in RISA-3D are a powerful way to model how floor systems distribute lateral loads. By forcing all connected nodes to move together in-plane, they effectively capture the stiffness of a concrete slab or diaphragm deck—often simplifying analysis without sacrificing accuracy. However,...
The ASCE/SEI 7-22 Minimum Design Loads and Associated Criteria for Buildings and Other Structures introduces significant updates from ASCE 7-16. The most notable changes impact wind and seismic provisions, along with new load combination rules that directly affect structural analysis and design....
The ANSI/AISC 360 Specification for Structural Steel Buildings is the cornerstone reference for structural steel design in the U.S. The transition from the 2016 edition (ANSI/AISC 360-16) to the 2022 edition (ANSI/AISC 360-22) reflects both advances in research and the need for closer alignment...
With the adoption of ASCE 7-22, the concept of a multi-period response spectrum has been added to seismic design requirements. While this provides more accurate hazard representation, it also means engineers need to generate and input additional site-specific data. This quick workflow shows how to...
While members (beams and columns) follow conventions tied to their local axes, interpreting results for wall panels, plate elements, and design strips requires a slightly different perspective. These elements deal with both in-plane and out-of-plane behavior, and the sign conventions can change...
RISA software products use different sign conventions depending on the product’s purpose and typical use case. While the conventions are logical within each program, they may appear inconsistent when moving between tools like RISA-3D, RISAFloor, RISAFoundation, and RISAConnection. This article...
We often get asked: “Should I model my foundation as a slab or a spread footing in RISAFoundation?” While both are valid options, they use very different analysis methods, and the results can vary accordingly. In this article, we’ll walk through a side-by-side comparison, using the same modeled...
Light-framed construction has become increasingly prevalent in mid-rise and modular development, driven by its cost-efficiency, speed of construction, and adaptability. But with flexibility comes complexity. Engineers designing with wood and cold-formed steel (CFS) must navigate a unique set of...
