Month: October 2015

Learn How to Apply Structural Loads

Once the structural engineer has defined the geometry of the structure for analysis, the next task is to apply loads representative of the loading which will be applied to the structure in use to simulate model behavior under different types of actions.

Structural LoadsStructural loads are forces applied to a component of a structure or to the structure as a whole.
In React Structures, before you apply any loads you should define load cases. A load case represents a group of loads of the same nature, such as dead, live, wind (in one direction), snow, accidental, or seismic.

Structural Load TypesReact Structures allows for the definition of many different types of loads such as nodal, linear, and surface.
When you create a new project, a self-weight load case is added automatically. It is used to apply a self-weight load to the model while you define elements of your structure.

The Load tab in the Ribbon contains all load features. If the Load Case dialog contains only an automatic self-weight load case, clicking + adds a dead load case with a consecutive number. When you add the next load cases, cells with their parameters are populated based on the last load case.

Add Load CaseWhen you have added a load case you can select a nature of it using the combo box.

Select Nature

Natures such as: dead, live, wind, snow, accidental, or seismic are available.
Labels are created automatically and you cannot edit them. They are abbreviated names of load cases indicating their natures. For example, LL1 is a label of the first live load case in the project. You can name your load case using the Case name field.

Load Cases

Once you have created all your load cases it’s time to apply structural loads related to these load cases.

In React Structures Tech Preview 1 four types of loads are available:

Types of Loads
You can run all these tools and switch over between them using a very convenient and productive Dialog Organizer mechanism.

Dialog Organizer

Before you set up the parameters of your loading you should select a load case.

Select Load Case

When you want to apply linear or surface loads to the structure you can do this in the global or local coordinate system.

Coordinat System

In addition, you have the Global with projected load option. It specifies a load direction in the global coordinate system. You can use it to apply the load to the element length projected on the plane that is normal to the load direction.
This is often used for snow loads to reduce the load intensity when you apply loads to inclined member or surfaces.

Projected Load
Similar to the support definition you can use two assignment modes to apply loads to elements.
You can use the Direct mode to apply loads to elements that you select directly in the drawing area. You can select elements consistent with the load type. For example, for surface loads, you can select surface elements. You can select one element at a time. The load is applied instantly and the load contour is displayed in the model view.

Direct Method

You can use the Selection mode to apply loads to a selection of elements.

The elements in your selection that are consistent with the load type are displayed in the selection box. When you click Apply the loads are added to the elements and displayed in the model view.

Select Method

You can control visibility of load symbols and its values using two options in the Status bar.

Visibility of Load Symbols Once you have applied all loads to your structure you can review them by switching between load cases using the combo box in the Object Inspector.

Select Load Case 2

Wind LoadIn order to apply wind loads you can also perform wind simulation. The wind loads simulation feature enables you to simulate a wind flow around your structure, and to generate wind loads automatically.

Wind Simulation Dialog

This feature is especially useful with structures that have a complicated geometry, and for which it is usually difficult to define the right wind loads. The wind simulation acts as a wind tunnel, and displays colored pressure maps on the model in order to help visualize and understand the effects of the wind.

Wind Simulation
With React Structures you can apply structural loads of various types quickly and easily to any type of structure.

Excitation at NCSEA

To announce the release of React Structures, Brian Frank (Autodesk Product Line Manager) and I attended the National Council of Structural Engineers Association (NCSEA) in Las Vegas. There were nearly 400 structural engineers from the United States attending this event. This was our first time attending NCSEA and we found it enlightening in several ways.

NCSEA Summit 2015

For starters, we met a range of structural engineering firms: those working on a variety projects like bridges, building and industrial facilities. This was evident in the gallery where we saw projects on display for the 2015 Excellence in Structural Engineering Awards.   Secondly, we met some real out-of-the-box thinkers (yes and they were engineers :) ). Brian Dekker, owner of Sound Structures and future President of NCSEA set up a “shake table” with Legos to demonstrate the concept of resonance frequencies of structures. I’ve been fascinated with “eigen values” ever since taking an Earthquake Engineering class in college. So the shake table really made the trip for me.

NCSEA Summit 2015

What we also found interesting was the number of engineers voicing a common need for structural analysis and design software that is easier to learn, more modern and that connects to BIM. Hearing this at NCSEA really helped validate the direction we are going with React Structures and so it was good to listen and hear the needs from fellow structural engineers.

For those of you participating in the React Structures technical preview, we appreciate your feedback. Your efforts will help guide our efforts. We will be off to Vegas again in December for AU 2015 and I encourage you to attend. We will have some special customer sessions about React to get more direct feedback from users. If interested in attending please shoot Brian or I an email.

Check Out React Structures Sample Models

We have included two sample models with React Structures Tech Preview 1. You can use these models to fast-forward through modeling and review React’s results exploration features quickly. Just open the example file, hit “Analyze” and you can dive into deformations, displacement maps and force diagrams in no time!

Sigma Model Deformations

You can access the sample models directly from the React start screen, using “Explore Sample models” link. You can also find them in your Documents folder, stored in Autodesk React Structures Tech Preview directory.

Use "Explore Sample Models" to access the files.

Sigma model is a typical steel structure (concrete floor, steel beams and columns, curtail walls). Omega model is a reinforced concrete structure with steel shed on the top floor.

Omega Sample Model

As always, head over to React forums to post your feedback!

Learn How to Work with Supports

With React Structures you can assign support conditions quickly and easily to any type of structure. Watch and learn how to work with supports in Autodesk React Structures.

Jump to the React forums to discuss.

Did You Know About the Dark and Light Themes?

While developing React Structures we have added a lot of useful little features that make your modeling easier. In this series of posts, we will be presenting some of them. Let’s start with the light and dark theme.

You can choose between two themes for React Structures Tech Preview 1: the Dark theme with a dark gray background,

DarkThemeor the Light theme with a light gray background.

LightThemeThe default theme for the user interface is the Dark theme. If you feel more comfortable with a light background color, you can change the theme at the bottom left of the status bar.

SwitchingBetweenThemesHead over to React forums and let us know what you think about color themes!