Rammed earth research

I have recently completed a PhD at the University of Durham. This research looked at the fundamentals of rammed earth construction and the analysis and repair of historic rammed earth buildings.

PhD - Analysis of historic rammed earth construction

Paul Jaquin January 2008

My PhD looked at how best to understand and preserve historic rammed earth structures. This was done by considering the fundamental forces which bind rammed earth, and showing that the surface tension of water may be responsible for the increased strength and stiffness of earth buildings. This insight led to a better understanding the structural behaviour of rammed earth and other earth buildings.

This improved understanding allowed more complex analysis techniques to be used, and techniques were developed which can now be transferred to both modern and historic rammed earth structures.

The PhD also looked at typologies, failure and repair of historic rammed earth. Around fifty sites in India and Spain were visited, with detailed recording and analysis allowing a much better understanding of how historic earth structures fail, and may be repaired.

Much of the work has been presented at international conferences, or has appeared in refereed journals. For full details, see publications

Historic rammed earth sites

During the course of my PhD, and following the research, I have visited a number of historic rammed earth sites around the world. Details of these sites can be found on the sites page.

Further research

During the course of my PhD I identified many further areas of research which I feel should be investigated. In particular I have identified areas which may now be better investigated following the discoveries made during my PhD.

These areas include:

• Determination of peak cement content for earthen building
• Unfired clay brick mortars
• Rates of decay in historic rammed earth structures
• Compaction optimum moisture content
• Review of existing UK rammed earth projects
• Wall top coverings
• Structural rammed earth
• Repair methods for damaged historic earth buildings
• Seismic loading
• Relative humidity in earthen buildings
• Fly ash in rammed earth
• Urine mud bricks

I have worked with Engineers without Borders and have prepared a document giving details of these and other projects.

These projects would particularly suit university final year engineering projects. If you are interested in these or similar projects, please contact me.

Research at Durham University

Research at Durham is continuing under Dr Charles Augarde and details can be found on the Earthen construction @ Durham University web pages.

Other rammed earth research

There are a number of other researchers actively involved in rammed earth research. In the UK, Dr Matthew Hall of Nottingham University is working on the thermal modelling of rammed earth, and Professor Peter Walker at Bath University is working on a range of earthen materials.

For details of all the current research into earthen construction, see the research links page.