Assessing the freeze-thaw deterioration of unstabilised rammed earth walls

Eligibility: UK/EU/International

Award Details: Tuition Fees + Bursary

Duration: 3 years Fixed Term (Starting in September)

Application deadline: Ongoing

Informal enquiries are essential before application; contact Dr. Vinh Doan to discuss this opportunity.
Excessive humidification of rammed earth occurs in existing buildings due to rising capillary where the base of the wall in contact with the traditional substructure and/or due to water vapour condensates inside the wall because of a little or no permeable vapour layer from installing insulation or plastering (cement coating). As rammed earth is the breathable envelope of the house and unsuitable insulation and plastering materials risk hindering the exchange of heat and water vapour of rammed earth wall, intruding its control over these exchanges and locking the moisture within the wall. This happens to many existing rammed earth buildings as per regulation requirements for refurbishment projects to improve thermal insulator of the building enclosure.

Water and frost are the most destructive natural causes to erosion and deterioration of unstabilised rammed earth. In order to assess the freeze-thaw durability, several rammed earth samples representing the aforementioned problems in existing buildings and from new construction will be subjected to a number of cycles of freezing and thawing using the climatic simulation chamber.

The scope of the PhD project is conducting a number of tests using a climatic condition chamber to evaluate the hygrothermal performance and assess the durability against rainfall erosion and freeze-thaw deterioration. The following questions will be addressed:

- How the hygrothermal properties of these rammed earth constructions can be experimentally measured inside Coventry University Climatic Chamber?

- What is the rate of capillary moisture ingress of unstabilised rammed earth walls in cultural heritage? In case of insulation and/ or plastering?

- How do insulated/ plastered unstabilised rammed earth walls in existing buildings perform under freeze-thaw deterioration conditions?

- Does freeze-thaw cause any problem for new construction rammed earth? Notably during the onsite manufacture process.

The modelling will be studied in cooperation with CNRS-ENTPE (France).

The work will focus in the first instance of freeze-thaw deterioration of rammed earth in new construction. The experiments for rammed earth walls in existing heritage buildings will be conducted to simulate several scenarios: (1) rising capillary caused by its contact with the traditional substructure; (2) high humidity level due to unsuitable insulation; (3) high humidity level due to plastering.

The scholarship is open to exceptional UK/EU and international students.

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
- 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)

Additionally

- Knowledge and/or experience with relevance to methods or topics of building performance, measurement and monitoring.
- A good knowledge of soil mechanics, building physics and non-conventional building materials.
- Proven skills in numerical modelling, analytical skills, and critical thinking and reviewing.
- Highly self-motivated and organised, flexible, independent and creative thinker.

Eligibility & Application Procedure

Application Procedure:

Application information can be found in our how to apply section. Before completing the application please contact Dr. Vinh Doan [Email Address Removed] (cc'ing [Email Address Removed] when you do) for an initial informal discussion about the opportunity.

Eligibility:

All UK/EU/International students are eligible to apply that meet the academic requirements, the eligibility criteria can be found here: http://www.coventry.ac.uk/research/research-students/research-entry-criteria/