The Strength of Lego

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Capped and Uncapped (2×1 brick) Lego specimens before compression tests

Had an absolute grand time crushing Legos with Hailey Todd and the virtual ventures summer camp at Carleton University this week. Thought Id pass on some of the results we observed. Unlike the previous study conducted for the BBC where only one Lego block type was tested, we really wanted to understand what happens with Lego under a realistic building configurations and loading scenarios. So we took typical Lego blocks of 1×1, 1×2, 1×3 and 1×4 brick sizes and tested them in a loading actuator with compressive displacement control (mm per minute).

What we observed was that as the size increased so too did the ability to carry load (see graph below). Though it was not proportional to the added stud-brick for each block. We did not cap the Legos because we wanted to see the full effect. Basically the failure mechanism is as follows, the test begins with load being applied and the Lego brick ‘stud’ is pushed into the block giving a flat loading surface along the top of the block, there is a small elastic phase and then we begin to crush the Lego block (its peak load). Later we did cap the Lego and saw some interesting differences in peak load and failure pattern (see below).

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Elementary school students as part of the virtual ventures summer camp at Carleton crushed Lego to introduce them to how building materials behave under load. An unexpected non-proportional trend in load increase with brick area increase was observed.

We opted to use Lego as a teaching example as its a relatable building material to youths. I think its a gate way to show them just how strong materials are when you can relate them to the day to day lives, obviously we get them hooked there, and progress to crushing concrete and breaking steel much after.

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After testing the 2×1 brick Lego. The uncapped Lego failed at 4.2 KN; whereas the capped lego failed at 3.7 KN. Both blocks terminated with the same deformation level in mm. Not the different failure mechanisms are because the load is applied differently throughout the lego.

United Kingdom Fire Expedition 2016

 

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Cellular beam construction in the United Kindgom

The research team recently traveled to the United Kingdom. Students (three of them + one former) presented 4 papers with me. Their work was on aging populations, engineered timber, concrete structures after fire, and advancing our knowledge in fibre reinforced polymer constructions at the Interflam conference. All the papers were well received. Our human behavior in fire paper can be downloaded off research gate here. Beyond this conference the students joining (three of them) had the opportunity to visit Arup’s London office for two days and the University of Edinburgh for a day.

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The Shard a PT concrete and Cellular beam Iconic structure in London, and currently the tallest UK building

This trip has become a staple on my research team. We also did this trip in 2015. Reflecting on the last experience, I felt that the trip was too short and did not have enough exposure to contemporary design. In that sense this years trip (with the thanks to the good folks at Arup in London and Edinburgh Uni) expanded on this experiential learning trip. The theme of the trip is the interaction between research and consultancy design practice. The trip’s itinerary to the United Kingdom included the following: Interflam Conference from July 4th through 6th; on the 7th a visit to Arup London (where three design projects were reviewed with the students as well as a nice presentation given by myself to the Arup structural skills team); On the 8th the students traveled to Edinburgh University to tour the fire facilities and meet their research team. Afterwards on the 9th, the students had an opportunity to take in the number of heritage structures in Edinburgh as well as visit the Edinburgh Fire Muesuem (see previous post – the museum may be permanetly closing soon). On the 11th of July, the students visited the iconic structures of London. We started with the Grade I heritage LLoyd’s building (yes it is heritage…..) to vsiting the Shard (pictured). The Carbuncle Cup winner the FryScraper was also visited (we also saw the Razor 2010’s winner also called the Strata). On the 12th, the students

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Tate Modern.

visited Arup once again for a day on Human Behaviour in Fire (also to consider many heritage structures). This included two project reviews and a site tour of the Tate Modern. The students gave a presentation on their Human Behaviour in Fire  and Engineered Timber work. This was a great experience for them as they got to present to engineers from offices in China, Uk and North America via a conference. On the 13th the students returned home. It was awesome the amount of time provided to the students at Arup and Edinburgh – thank you to those awesome people!

 

So often in research students tackle ‘pie in the sky research projects’ which are dissociated to growing our immediate capabilities to better design our existing and planned infrastructure. The dis-association between research and consultancy is severe in some cases and a communication barrier is often present. We need to get students out there to see whats being built, meet people who are building, see what these engineers need. We need not just motivate students – we need to inspire them that they can make an impact.

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A typical ‘Sunny’ Day to see London’s Skyline.