Showing posts with label connections. Show all posts
Showing posts with label connections. Show all posts

Wednesday, September 20, 2017

Emulation for optimal structural design.

Emulation for optimal structural design.

 

If you are fond to ancient world engineering and the surprising achievements of the humanity such as the  Pyramid of Egypt, you will notice that the Pharaohs of the ancient empire  had to perform some failed attempts before they could build the Giza Pyramids Complex. After the famous engineer, architect and erudite Imhotep built the  stepped Saqqara pyramid, of seventy meters high, the precedent Pharaohs attempted the construction of next level pyramids.

But the next attempt, the Medium pyramid, ended up collapsing under its own weight, while the next one, the Dahshir pyramid, had to suddenly change its angle, since the collapse of its internal structure seemed to be unavoidable.

We had to wait until the Red Pyramid at short distance from the previous one, for achieving the adequate resting angle for obtaining the proper structural integrity.
Red Pyramid
Thousands of years later, during the XIX century when the railroad network extended to all the corners of the industrialized countries Great Britain and  United States, as the leaders, the need of saving chasms and rivers, fomented the construction of bridges.

Not everybody was successful, Stirling, Broughton, Chester, Wooton, Tay in Scotland and Inerythan, were example of this delirious and tragic beginning of the structural engineering in the United Kingdom of the industrial revolution.

North America, also had its named failures, some already during the 20th century and several filmed as classic catastrophes movies.

All these structural failures that costed dozens of deaths and wounded helped as experience so we can now enjoy of safer structures, but  not quite still.

Even so this doesn't mean we  no longer have structural failure. New needs present new challenges. The frail for urban space leads to the constriction of structures simultaneously higher and deeper, where the deep excavations incidents present themselves at an alarming rate.

Here is where structural analysis software such as Autodesk Robot Structural permits us design structures and test them before wind or seismic load cases that may be catastrophic. Including big frames structures subjected to accidental loads.
Accidental Loads
This doesn't mean though that we should design thinking always on the catastrophes. Actually there's regulations and design codes regarding the cases that should be considered. The safety coefficients that should be respected and the accidental load cases that must be included.

In more practical cases, Autodesk RSA permits us to try different structural proposals without more work than changing  the beams and columns section selection.

It's not unusual, that our first structural proposal happens to be somehow oversized. We all design with certain degree of fear that our design calculations present some error or that our sections cant bear the loads. Furthermore, that the design loads won't be respected and that the structure get overloaded. It's something rather common.

Autodesk Robot Structural allows us to observe the deformations in the structure in a graphic way before all the different load cases and combinations. The structure deforms affected by the a certain scale, so we can further appreciate each load effect.

From there we could verify the shear and bending moment graphs, but the most evident aspect is observing the deformations as we check each section.
Structural Deformations
With this information we can test different sections until we get to a solution that offer us the best relation between safety and economy.

It's easy to switch structural elements of steel or reinforced concrete and observe the deformations and critical points.

Before the same set of load cases combinations we can check different steel and concrete elements, observing the results through deformation that may be animated, but that will throw the results in a way of a color code and precise values over the deformation points.
Since we can determine the deformation scale, is quite easy to appreciate how the stresses are exerted over the structure.

From these first results and the real-time displayed safety coefficients it's possible to switch structural elements for slimmer or lighter members and observe the deformation and coefficient changes.

The simulation can be taken to a critical point and from there test members, connections or far more creative geometry elements that resolve the transfer of weight and stresses in a more clever way,so we can obtain lighter and more resistant structures.

As oppose to other calculation programs where the changes in the structure involves a long process of mathematical rethinking, in Autodesk Robot Structural such process is graphical making the analyst feel motivated to perform a bigger amount of changes y tests, as if it was some sort of virtual construction game.

The effects of each change in the structure are also displayed in a graphical way, being possible to work with complete combinations involving wind, seismic and accidental loads, including any other event to which the structure could be subjected along with its respective foundation.

published by Virginia E-Learning.

Friday, July 8, 2016

Autodesk Robot 2016 Tutorial. II - Steel - Foundations and Trusses

Robot Structural Analysis TutorialAutodesk Robot 2016 Tutorial. II - Steel - Foundations and Trusses

For Analysis and Design of Warren and Pratt Trusses, Foundations and Wind Loads.















Welcome to Autodesk Robot Structural Analysis Professional 2016 Tutorial. Steel. Part II. 

For Design and Analysis of Warren and Pratt trusses, Foundations and Dynamic Analysis of Wind Loads over Steel Structures.


Once you’ve mastered the basic principles of the design and analysis of steel structures, we’ll take a step further in Autodesk Robot 2016 by teaching you how to work with Steel Lattice Structures, including Warren and Pratt Trusses; one of the most popular Steel Structures Elements.
We’ll start our course by designing a two-dimensional version of these elements in both Revit Structure and Autodesk Robot. Also approaching arch, inclined and straight roofs.
We are also going to work with Steel Structures in big frames as well as with the design of connections using either bolts, plates, angles or welds and all the detailing for obtaining a safe connection, which the software analyze and test.

Another aspect we’ll observe is the design of foundations, analyzing its behavior under different stresses and soil compositions.
And how could we forget of the subject of Wind Analysis. One of the aspects that Autodesk Robot obtains through a Dynamic Analysis which ponders wind speed and direction, transforming these two factors into specific load cases. 

As you might know Autodesk Robot automatically generates the plans and calculation memory, according to specific design codes and regulations. And since Autodesk Robot is an international level software, you won’t issue specifying the design codes of your country.
Finally, and as in all of our courses, you’ll have access to our expert engineers through Virginia E-Learning Support Center.

To get this full tutorial visit: http://www.virginiaelearning.com/