Guide To: Flexible Diaphragm Load Distribution in RISA
October 17, 2023

Guide To: Flexible Diaphragm Load Distribution in RISA

It is important to understand how RISA is modeling your load distributions when applying flexible diaphragms. The flexible diaphragm distributes loads based on tributary area, but RISA breaks up the areas based on the nearest support elements on either side. When RISA sees support elements on both...

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New Features in RISA-3D v20.0.4 now Available!
November 4, 2022

New Features in RISA-3D v20.0.4 now Available!

We are pleased to announce our latest RISA-3D release. Our teams have been working hard to add the features and functionality that our customers have requested as well fix some of the issues that have been reported. New features in this release include:

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Video: Using Various Diaphragm Types in RISAFloor
February 26, 2021

Video: Using Various Diaphragm Types in RISAFloor

RISAFloor supports the three fundamental types of diaphragms used in structural analysis: rigid, semi-rigid and flexible. Watch this video to learn how to consider each of these diaphragm types within the same model and same floor plan.

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Accidental Torsion for Semi-Rigid Diaphragms in RISAFloor
December 11, 2020

Accidental Torsion for Semi-Rigid Diaphragms in RISAFloor

The latest releases of RISAFloor (Version 15.0.1) and RISA-3D (Version 19.0.1) include consideration for accidental torsion and eccentric loading for semi-rigid diaphragms according to requirements outlined in ASCE 7, Section 12.8.4.2.

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How Do Flexible Diaphragms Work on Sloped Roofs?
April 23, 2020

How Do Flexible Diaphragms Work on Sloped Roofs?

RISAFloor supports the use of flexible diaphragms on both flat and sloped roofs. Before reviewing the workflow for utilizing a flexible diaphragm on a sloped roof, it makes sense to review and understand the basic behavior of flexible diaphragms within RISAFloor. To do this, please first review the...

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Understanding Wall Panel Forces with Rigid Diaphragms
June 20, 2019

Understanding Wall Panel Forces with Rigid Diaphragms

When modeling building structures using steel or composite steel floors, engineers typically utilize rigid diaphragms to distribute lateral loads (wind and seismic) to lateral load resisting elements such as shear walls, moment frames and braced frames. Rigid diaphragms represent a plane of very...

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RISAFloor & RISA-3D: Two Buildings on the Same Podium
January 17, 2019

RISAFloor & RISA-3D: Two Buildings on the Same Podium

RISAFloor is the RISA Building System’s floor design software which allows users to design with composite decks, elevated concrete slabs and more. When paired with RISA-3D, the two create a complete solution for the analysis and design of multi-story structures, including two buildings on the same...

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Semi-Rigid Diaphragms now Available
April 12, 2017

Semi-Rigid Diaphragms now Available

RISAFloor now has the ability to model a Semi-Rigid, Rigid or Flexible diaphragms to distribute lateral loads. For more information about the different diaphragm types, click on the link below.

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