They are comprised not of stone or brick, but of a material called rammed earth. Considering that both structures have been standing for well over 1,000 years, doesn't this process deserve a second look?
Rammed earth is created when clay-rich soil is mixed with lots of water and a natural construction stabilizer. In ancient times, stabilizers often included animal blood, urine, bitumen and even certain plant fibers.
Structures designed with rammed earth can be further reinforced and supported to optimize sustainability. For instance, various timbers can be used to offset heavy weight and offer additional stabilization. In modern day, one only need to substitute cement for those aforementioned stabilizers, and the structure is made exponentially more secure. This new mixture—referred to as cement stabilized rammed earth or CSRE for short—has the same strength ratings as cement. For reference, that means it can withstand about 6,000 psi of pressure.
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Rammed earth is created when clay-rich soil is mixed with lots of water and a natural construction stabilizer. In ancient times, stabilizers often included animal blood, urine, bitumen and even certain plant fibers.
Structures designed with rammed earth can be further reinforced and supported to optimize sustainability. For instance, various timbers can be used to offset heavy weight and offer additional stabilization. In modern day, one only need to substitute cement for those aforementioned stabilizers, and the structure is made exponentially more secure. This new mixture—referred to as cement stabilized rammed earth or CSRE for short—has the same strength ratings as cement. For reference, that means it can withstand about 6,000 psi of pressure.