User Guide

RISA-3D User’s Guide
Version 5.0
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Overview
Using computer software to perform structural design is essentially a three-step
process. First, you define your model. Next you solve that model to obtain
solution results. Last, you review those solution results to see how your model
performed and determine if changes are needed. Usually you will need to repeat
the cycle several times before you arrive at a final design. The purpose of RISA-
3D is to speed up this process.
RISA-3D has two complementary sets of tools; graphics based drawing tools and
customized spreadsheets. We say “complementary” because these tools work
together very closely. Everything that you do graphically is automatically
recorded in the spreadsheets for you. You may view and edit these spreadsheets at
any time. The converse is also true; what you enter and view in the spreadsheets
may be viewed and edited graphically at any time. You will be thoroughly
exposed to both sets of these tools in this tutorial.
Defining the Model
Some data such as cross section properties, load combinations, oddball joint
coordinates, etc. are most easily entered numerically, and the best tool for numeric
input is a spreadsheet. Other data such as regularly spaced joints, member
connectivity, regular loadings and wholesale changes are better handled using
graphic drawing tools.
Typically you’ll use the spreadsheets to define some preliminary information such
as material and section properties. Then you will proceed to the drawing grid and
graphically draw the bulk of your model and apply loads.
Other graphic edit features are built around RISA-3D’s graphic selection tools.
These features let you graphically edit the model or parts of it. For example, to
modify boundary conditions, you would choose the condition you want to apply
and select the joints to modify.
Keep in mind that almost all the model data can be edited either way (graphically
or numerically in the spreadsheet). You can decide for yourself which method is
preferable.
Solving the Model
Once you’ve got the model defined, you’ll need to solve the model. RISA-3D
features fast 32-bit solution speed, so your model solutions will be pretty quick.
Once the model is solved you’ll be presented with the results.