David Easton is thrilled to keynote the First International Conference on Rammed Earth Construction in Perth, Australia from 10 to 13 February 2015. The conference is hosted hosted by The University of Western Australia and will bring together researchers, engineers and practitioners in order to communicate the latest developments in the design and analysis of rammed earth structures.
David's keynote will focus on themes of creating unified definitions and standards for rammed earth construction as well as increasing the sustainability profile of rammed earth by limiting or eliminating Portland cement from mix designs.
Here are a few select quotes from the keynote :
“Who in his right mind would believe that you could simply pound dirt into durable shelter - that walls built this way could stand up to wind, weather, and gravity? Who in his right mind would think you could make a business out of such a thing, that people would actually pay for it? What were we thinking? That here was an opportunity to support our families and put our kids through college? That we would get rich and successful and launch a global renaissance? Mark Twain once said, ‘it takes two things to be successful in life - ignorance and confidence.’ Look at us old timers today. What in the world made us stick with the idea of rammed earth? Was it ignorance, or confidence?”
“Is rammed earth only pure compacted soil or is it any aggregate pounded into a monolithic wall, whether or not blended with stabilizer? Is it the act of ramming, or the composition of the earth? Is a poured earth wall rammed earth? Is a shot earth wall rammed earth? Is a wall of compressed earth blocks rammed earth? What defines rammed earth? The material, the method, or it’s monolithic character? Does cement stabilization change the character of the wall so much that we can no longer call it rammed earth?”
“Why do the world’s codes differ so radically on the perception of what is safe rammed earth - 0.25 MPa (30psi) in some countries, 17 MPa in others? In soils, it takes a minimum of 10% Portland cement to achieve strengths of 17 MPa, less cement in crushed aggregate. What this means, distressingly, is that there is nearly twice the cement in a 400 mm stabilized earth wall than there is in a typical concrete wall, and every pound of cement calcined generates nearly a pound of CO2.”
“What is it that makes rammed earth so attractive, so alluring, so captivating? What exactly is the magic? Is it simply the hygroscopic ability of raw earth to maintain optimum humidity levels within a space? Or is it the way thick earth walls can soften sounds and provoke a sense of calm? Perhaps they capture the essence of biophilic design, that the earth walls provide a source and sense of connection to the natural world, distilling natural materials to their elegant simplicity and rightness of fit.”
“The recent interest in biophilia - architecture to connect people with nature - could not find a better mascot, a better poster child than rammed earth. A thick, strong earth wall acts like a filter, excluding the noise and the stress that is outside, creating a positive, beneficial environment within. It’s pure and simple.”