ISSB Excels in Strength Tests

Posted on August 26th, 2019

HYT is well underway with our training project in the world’s second largest refugee settlement, Bidi Bidi. A total of 18 South Sudanese and 10 Ugandan youths are undergoing intensive training thanks to an ongoing partnership with Mercy Corps.

HYT Trainees
Day 1 of training in Bidi Bidi in partnership with Mercy Corps.

Planning Permission

In Uganda’s extreme north an environmental crisis is following its ongoing humanitarian counterpart. Trees are becoming scarce, the lack of forest cover is increasing the area’s vulnerability to climate change; exposing it to desertification and soil degradation.

In February 2019, HYT arrived in Yumbe with a viable alternative to the environmentally devastating burnt brick. Interlocking Stabilised Soil Blocks (ISSB) require no firewood in their production, far less concrete during construction and no transportation costs. Our innovative construction practices were met with cautious curiosity.

Introducing the benefits of ISSB to the District, UNHCR and Mercy Corps Partners.

The District Engineer, Settlement Commandant and UNHCR are responsible for construction, quality control and strategy within the settlement. They have the monster task of coordinating the effort to bring the refugee’s standard of living to an acceptable level.

HYT is thrilled that our training has 10 female participants in Bidi Bidi.
With the pressure on HYT to showcase ISSB technology, we had ISSB master Philip Yiga overseeing the project.

Passing the First Test

28 days after the first block was pressed, a sample was taken to Teclab Kampala, an independent material testing lab. According to UNBS(2011) the Uganda standard (US849), states that blocks must achieve 2.5 Mega Pascals (MPa) for dry compressive strength to be used in construction. Our ISSB blocks averaged 5.1MPa, this is the equivalent force of 0.51kg pressing on every squared millimetre of the blocks surface!

Blocks are weighed and measured before being crushed.

Not only have our blocks far surpassed the required strength, they have saved 16.4 tons of firewood that would have been used in an equivalent structure made out of burnt brick!

The first round of testing was a great success.
Specialized machines compress the blocks

This is a huge moment for HYT, in an epicentre of Uganda’s international aid and development activity we have irrefutably displayed the power of ISSB technology. International aid should not be spent on environmentally destructive practises when there is an affordable, safe and sustainable option available. HYT is gearing up to help NGO’s and government bodies make the switch to safeguard the environment for future generations.

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Winners of the Ashden International Award for Sustainable Buildings 2017.

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