Model development for temperature-dependent visco-elastic granular materials

Infrastructure is the backbone of a healthy economy.  Transportation and specifically roads connect people, goods, and services.  However, the many positive benefits of infrastructure development must be weighed against cost and the potential environmental impact.   Recyclability is a novel feature of hot mix asphalt (HMA) which is one of the most common materials for road construction.  Recycled HMA can be re-heated and used in new road construction, thereby reducing the environmental impact of infrastructure development.  Processing and incorporating recycled HMA is very challenging in part because of a limited understanding of the thermal and mechanical behavior of the mixture.  The presence of the bitumen binder in HMA means that the visco-elastic properties of HMA are highly temperature-dependent.  Most prior work on HMA has focused on in situ performance where the temperature regime is limited to atmospheric conditions, but in the production process the temperature range is much higher meaning conventional continuum and discrete models of HMA are not valid.  A robust model that covers a full range of temperatures will help improve how simulation can be used in equipment design and maximize the recycling potential of HMA.

This project will seek to develop a visco-elastic material model that includes the temperature dependence using state-of-the-art simulation methods such as discrete element method.  Work will focus on developing a model that captures the relevant thermo-mechanical behavior of HMA across a range of temperatures that is applicable at the industrial scale.  The project offers the student an opportunity to advance fundamental understanding of a common but complex material with immediate real-world impact.

The project is financially supported by Astec Industries and may include a three-month placement at one of Astec’s locations in the USA.

Further Information: 

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Closing Date: 

Wednesday, February 9, 2022
Tarmac Asphalt
Tarmac Asphalt

Principal Supervisor: 

Assistant Supervisor: 


An undergraduate degree in Chemical, Civil or Mechanical Engineering, Physics or a related discipline is essential.

Minimum entry qualification - an Honours degree at 2:1 or above (or International equivalent) in a relevant science or engineering discipline, possibly supported by an MSc Degree. Further information on English language requirements for EU/Overseas applicants.


Applications are welcomed from self-funded students, or students who are applying for scholarships from the University of Edinburgh or elsewhere.

Partial funding is provided by the industrial partner. The balance of the funding will require the student to secure a suitable scholarship such as an EPSRC College CASE Conversion Scholarship or an Edinburgh Doctoral College Scholarship. EPSRC eligibility requirements apply to the former, i.e., open to Home students or EU students who have been resident in the UK for 3 years. Details of scholarship opportunities are available from the supervisors.

You are encouraged to apply as early as you can as the application may close earlier than the deadline once a sufficient number of applications have been received.

Further information and other funding options.

Informal Enquiries: