Seismic Capabilities of Low Cost Housing in South Africa

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Academic Project of the Year: 2016 SIMULIA Winner

‘Project of the Year’ is an annual contest held by Dassault Systèmes where students from around the world are invited to submit projects created with Dassault Systèmes products and software.  Winners are chosen by votes from Facebook users and an overall winner is chosen by a jury at Dassault Systèmes headquarters.

This interview with SIMULIA winner, Greg Maybery, was conducted by SIMULIA Academic Programs Specialist, Ann Wodziak. Greg used Abaqus concrete damage plasticity material model for his project—and fan favorite—”Seismic Capabilities of Low Cost Housing in South Africa.” 

Describe why you chose this topic for your project.  Why does this workflow need to be analyzed? 

greg-maybery-poty-2016-simulia-winnerMy lecturer, Dr. Trevor Haas, is very passionate about assisting the less fortunate, and indicated to me that in South Africa, there are certain regions of the country which are susceptible to moderate intensity seismicity, specifically the Western Cape and nearby areas around Johannesburg. The URM structures within these areas are regarded as the most vulnerable types of buildings when subjected to seismicity, such types of structures have performed poorly during past earthquake of low to moderate seismicity.

This study was proposed by Dr. Trevor Haas as to investigate the sensitivity of low cost housing units in certain regions of the Western Cape province of South Africa to seismic events in an attempt to determine the risk that these structures pose to its occupants.

Describe how you executed the simulations.

When deciding on how to go about developing the FE models and performing the simulation of a URM structure during seismic activity, it was chosen to create an FE model which modeled the bricks and the mortar bond between the bricks separately. The brick elements where modeled using Abaqus concrete damage plasticity (CDP) material model. The mortar bond between the bricks was modeled as a surface based interaction. By using this approach the developed FE model was able to accurately replicate the linear and non-linear (when cracks start to form) behavior of masonry assemblages.

Were there any key technical challenges you faced along the way? How did you solve them?

Developing the surface based interaction between the brick elements was exceptionally tricky to define as the theory behind it is rather complex and Abaqus does not have one dedicated surface based interaction for this type of application. This was, however, solved by incorporating three different interaction models; i.e. cohesive interaction, frictional interaction and normal interaction.

What were the advantages of using simulation in your project?  

To perform these simulations by the means of physically conducted tests would be extremely costly and time consuming. It would also be extremely difficult to perform these physical tests accurately as the test specimens are rather large and specialized testing equipment would be required.

Why did you choose Abaqus over other simulation products?

Abaqus is a very popular FE modeling software package in South Africa, the Stellenbosch University also has the software available to the students to use. When completing the literature study of the thesis topic it became evident that Abaqus was capable of performing such simulations as similar investigations had already been conducted using the software package.

Do you feel that learning simulation skills in University will provide you with an advantage in your career? Please explain.

Yes, as when you are setting up a simulation you are required to investigate the material properties of the different elements that make up your FE model. Then, using these material properties and your understanding of how these different elements interact with one another, you have to construct your model in a fashion so that your model will replicate the behavior of a physically tested specimen.

Would you like us to promote a website or social media page to share more information on this subject?

I would like to thank my supervisor Dr. Trevor Haas, the University of Stellenbosch, and especially the superb Structural Engineering department which made this all possible.

To read the full submission of Greg’s project, click here. 

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Katie Corey

Katie is the Editor of the SIMULIA blog and also manages SIMULIA's social media and is an online communities and SEO expert. As a writer and technical communicator, she is interested in and passionate about creating an impactful user experience. Katie has a BA in English and Writing from the University of Rhode Island and a MS in Technical Communication from Northeastern University. She is also a proud SIMULIA advocate, passionate about democratizing simulation for all audiences. Katie is a native Rhode Islander and loves telling others about all it has to offer. As a self-proclaimed nerd, she enjoys a variety of hobbies including history, astronomy, science/technology, science fiction, geocaching, true crime, fashion and anything associated with nature and the outdoors. She is also mom to a 2-year old budding engineer and two crazy rescue pups.