Assessing the mechanical stability of earthen structures by Yield Design Modeling (YDM)

The Project
There are several million buildings in Europe made of prime materials (earth, stone), most of which must be renovated or have maintenance to simply bring them up to modern standards. Even if stone and earth are part of European Heritage, these materials can be included in modern architecture (see Wang Shu, Pritzker Price in 2012). Due to their very low embodied energy and their ability to act as moisture buffers to the indoor air of buildings they are interesting materials for the future.

Such structures are Non Tensile structures because their tensile strength is usually ten times smaller than their compressive strength. Therefore the tensile strength has to be neglected. There in the last decade, an increasing number of publications on earthen buildings, but not at a moment a widely accepted methods to assess the safety of new and ancient buildings.

The project proposes to use the theoretical framework of the Yield Design Modelling (YDM) initially developed for soils. This modelling was successfully already used to assess the strength of stone (and drystone) masonry structures (vaults and load bearing walls).

The YDM will be compared to experiments and other modelling currently done in other research centers in UK, France and Portugal.

For this, in addition to theoretical developments, the project proposes the development of experiments testing mechanical behaviour on equivalent homogeneous media (centimetre scale) and representative elementary volumes of earth walls (metric scale).

The upscaling will be built using periodic homogenisation for layers or blocks in the case of a rammed earth or adobe wall, by periodic homogenisation.

Duration: 3 years Fixed Term (Studentships are available to commence during academic year 15/16- start date January/April 2016)

About the Centre/Department
The Centre for Low Impact Building’s (CLIB) aims to be an academic and industry partner of choice in delivering real solutions to close the design versus in-use performance gap in the built environment.

CLIB staff enjoy a vibrant environment of collaboration across academic disciplines, other universities, practionners and industry to ensure that our research has proven impact on the global challenge for sustainability of the built environment that includes human factors.

Successful Applicants
- A minimum of a 2:1 first degree in a relevant discipline/subject area with a minimum 60% mark in the Project element or equivalent with a minimum 60% overall module average.

- In the event of a first degree classification of less than 2:1, a Masters Degree in a relevant subject area will be considered as an equivalent. The Masters must have been attained with overall marks at merit level (60%). In addition, the dissertation or equivalent element in the Masters must also have been attained with a mark at merit level (60%), or

- a taught Masters degree in a relevant discipline, involving a dissertation of standard length written in English in the relevant subject area with a minimum of a merit profile: 60% overall module average and a minimum of a 60% dissertation mark

Additionally:
- the potential to engage in innovative research and to complete the PhD within a three-year period of study
- a minimum of English language proficiency (IELTS overall minimum score of 7.0 with a minimum of 6.5 in each component)

Find out how to apply: http://www.coventry.ac.uk/research/research-students/how-to-apply/

See the website: http://www.coventry.ac.uk/research/research-students/research-studentships/assessing-the-mechanical-stability-of-earthen-structures-by-yield-design-modeling-ydm/