Summary, Draft 1

In the article, “How Volcanic Ash Strengthens a Roof Against Powerful Projectiles,” Williams (2019) proposes that having a layer of volcanic ash on the rooftops of building can increase protection from volcanic projectiles. A study by scientists from the Earth Observatory of Singapore (EOS) and the University of Canterbury (UC) was conducted to measure the ability of ash to cushion volcanic projectile impacts shot by a high-pressure air cannon. Tests show that having a five centimeters ash layer tripled the strength of the roof to withstand projectiles. While a thicker layer helps, it increases the risk of the roof collapsing. Scientists also believed that an asset would be more damaged when struck by multiple projectiles compared to one. However, the tests proved otherwise, provided tephra is deposited onto the roofs, leading to ideas of designing roofs with a 5cm layer of tephra. However, this method should be done on an individual basis by ensuring the shelter benefits from the tephra on its roof, and still withstand its weight. Therefore, buildings with reinforced concrete roofs are found to be ideal.