Image source: Course Faculty
Earth as a building material has been prevalent since time immemorial. In present day scenario, with sustainable building materials and appropriate building technologies being more relevant than ever, rammed earth wall construction has a lot of scope in its application on a global scale and to modern design sensibilities. It is cost effective and has favorable thermal properties. Earth, sand (around 25-30%) and cement/lime/natural materials (around 5-9%) are thoroughly mixed with water to get a homogeneous humid mix. This humid earth is poured in a slipping form in thin layers and then rammed to increase its density. Best soil for rammed earth is gravely or sandy rather than clayey. Sand is added according to soil quality to reduce shrinkage. A slipping type formwork has been designed and developed by Earth Institute Auroville and made by Aureka, Auroville. It can facilitate making of a rammed earth wall 24 cm thick, 240 cm high and up to 99cm long. The intent is to make alteast three rammed earth walls Wall 1. Using cement as the stabilizer, Wall 2 Using lime as the stabilizer and Wall 3 in which no stabilizer will be used. For wall 3 students will come up with their own mix experimenting with the proportions of soil, sand and alternative materials e.g. jaggery oil, alum, rice husk ash, fly ash, cow dung, straw, dry leaves and so on. It’s a hands-on workshop wherein participants will be involved physically in the construction of the rammed earth wall, in addition to basic theoretical inputs regarding the subject. It will be conducted in the form of lecture/presentation/talk/video shows inside the classroom or outside at the site location, as per the requirement.
Expenses for Students :- Materials - Rs. 1000/-, Local Travel - Rs. 2000/-