
October 26, 2010
How to Use Spreadsheets More Effectively in RISA
RISA includes various advanced spreadsheet operations that make reviewing input and results easy.
RISACalc in the Field: A Case Study in Confidence and Convenience It was a typical Thursday morning for Emma Ruiz, PE, a structural engineer at a small consulting firm in Colorado. Her day started with a site visit to a rural school renovation—a project where her team was assessing whether a portion of the existing structure could support new rooftop HVAC units. The original framing plans were incomplete, and as Emma inspected the roof framing, it became clear that the contractor’s proposed unit placement didn’t line up with the assumed beam layout. A decision had to be made, and quickly—the rooftop unit was scheduled for delivery the following day. The Problem: Time-Sensitive Field Check Emma didn’t have time to return to the office to rebuild a full model or dig through spreadsheets for older framing checks. She needed to verify—on the spot—whether the existing W10x22 steel beam could support the new loads at the proposed spacing. The contractor waited, the facilities director asked for reassurance, and Emma pulled out her tablet. The Solution: RISACalc in Action Emma opened RISACalc, selected the beam design template, and input the beam size, span length, and newly calculated roof loads, including snow and equipment…
Read More
RISA includes various advanced spreadsheet operations that make reviewing input and results easy.
To best understand how plates interact with each other you must first understand the concept of Physical Members. The important thing to keep in mind is that plates are not physical members. A plate is defined using either three or four joints, and it only connects to other plates at those joints....
When you have a deep column, it is necessary to model the beam so that it connects to the face of the column. This results in an eccentricity at the joint. RISA-3D offers two ways to model this eccentricity.
The customizable toolbar is a new feature in RISAFloor. It’s really useful and you may have overlooked it. You’ll find all of your familiar buttons as well some new buttons which make reviewing your model and results easier.
There are four different values for Unbraced lengths in RISA-3D, RISA-2D and RISAFloor. Two are for axial calculations and two are for bending calculations.
Members (beams, columns, braces, etc.) are defined in RISA by an I-Node and a J-Node. While you and I see a beam occupying physical space between two columns, most programs see a line between Point I and Point J. This is known as a non-physical member. See the image below:
If you have ever tried to solve a two-dimensional model in RISA-3D, you have ultimately run into instabilities in your model because your model has no out of plane restraint.
Our monthly "Structural Moment" newsletter is the best way to keep up with RISA’s product updates, new releases, new features, training events, webinars and more...