Project Everest

Work Update

Kicking Glass!

Connor Holmes
Connor Holmes | Feb 16, 2018 | in Knowledge Base

"If you are not willing to risk the usual, you will have to settle for the ordinary." - Jim Rohn

Based on the results from a scheduled meeting on the 17th of January 2018,Everest Recycling Solutions (ERS) decided to risk the usual and approach RMS Engineering and Construction about a glass substitute for gravel in 25MPa concrete aggregate. From this scheduled meeting testing was assumed to have commenced with results heavily anticipated over the next 7 to 28 days. This scheduled test, however, was delayed due to a diabetic diagnosis to the head laboratory coordinator as well as a paid leave on the behalf of our key contact, Gabe. Due to these unfortunate circumstances testing was postponed numerous times and officially commenced on Thursday the 15th of February 2018. This testing was visually confirmed by Connor and Khoen who oversaw the production of the concrete slurry.

The measure of the glass aggregate solution will be determined primarily from the 7day test with full strength results obtained 28 days from the slurry production. Full strength results will be compared to an internationally recognised gravel based concrete solution with an approximate compressive strength of 25MPa. The glass aggregate solution mimics the control solution with the ratio of sand to water to aggregate kept constant in order to ensure that fair and accurate results are obtained.

Prior to testing the glass aggregate Gabe was sceptical about the feasibility of using glass as a gravel substitute in 25MPa concrete. Due to the shape of gravel, gravel is exposed to significantly more cement per unit of surface area. As glass is planar with a rough wall thickness of 5mm, glass is exposed to a much lower cement ratio per unit of surface area. Based on this visual assessment Gabe expects glass to have a significantly lower bonding strength within the concrete solution [compared to gravel]. A 7 day test solution will be conducted on Thursday the 22nd of February, 2018 to further assess the feasibility of using glass as an aggregate substitute in concrete. A 7 day test is a good indication of the future feasibility of the concrete solution where a 70% test solution is considered to be a ‘good’ preliminary test solution. Based on a 25MPa controlled (20mm) gravel aggregate solution, a test result of 17MPa is expected for the glass aggregate concrete solution.

Additional to the previously stated strength concern, Gabe said that RMS Engineering and Construction currently require 2000T of gravel per month to keep up with their concrete demand. With that being mentioned, ERS currently collect up to 300kg of glass per month. This collection service provided by Project Everest is then seen as an insignificant input to the demand required for RMS Engineering and Construction. In order to combat this, at the 7 day aggregate test, partial testing could be seen as a promising solution. Based on research, 10-30 percent glass mixes are seen the most viable solutions and is something that will be followed up in the future.

We are all patiently waiting for the results to be released in 7 days and are all excited to watch the test solution shatter. We are all curious to see what you think the test solution will fail at – predict below!

My prediction is the glass aggregate concrete solution will fail at 12 MPa, with the goal being 17MPa

edited on 16th February 2018, 05:02 by Connor Holmes

Harry O'Donnell Feb 19, 2018

Representing Cambodian ERS we are optimistic and based only on the information in this post we call it at a 21MPa for failure.
Any other Cambodian ERS predictions are void.

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Philip Martin Feb 19, 2018

Another of ERS Cambodia, Using a different mix of shapes of glass aggregates researchers got 27 MPa so my guess is at 23 MPa

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Connor Holmes Feb 22, 2018

Testing was conducted today at RMS Engineering and Construction. The results were disappointing as the test solution failed at an underwhelming 11MPa, significantly under the required 17MPa. This premature failure was put down to the bonding capabilities of the glass as the concrete mixture was unable to bond to the glasses' surface. In order to further improve the bonding capabilities of the concrete solution, Gabe recommended that ERS 'roughen up' the surface area of the glass.

Further testing is a possibility with the aggregate comprising of 10mm glass and 20mm glass. Partial testing is still a future option to be explored (glass and gravel as the aggregate).

Thanks all for the interest in the testing of the aggregate solution, Everest Recycling team - Timor Lestè.

Reply 0

Andrew Vild Jul 2, 2018

Status label added: Work Update

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