Mohammad Kheradmand, PhD

Development of research activity in the scientific area of Structural and Material Engineering (Civil Engineering), with particular emphasis on multi-physics approaches for the numerical simulation of thermal-structural behaviour of construction materials. More specific information about expertise related to mortar multi-physics simulation and experimental characterization/monitoring can be found in the following topics:

• Thermal behaviour of hardened mortar, in view of thermal simulation. Particular attention is given to a sound choice of models and model parameters based on experimental evidence.

• Study of thermal fields associated to phase change effect of phase change materials (PCM) incorporated into mortar. Use of a finite element software suitable for 3D analysis of temperature development in mortar incorporated with PCM for ambient thermal comfort applications. The numerical simulation interests are complemented by the experimental work related to energy balances in model, involving conduction/convection effects.

• Incorporation of Phase Change Materials in plaster mortars for enhancement of thermal comfort in residential buildings.

• Study of phase change behaviour field development in hybrid PCM (more than one type of PCM), in view of its accuracy of different methods to actual specific enthalpy intrinsic of PCM (particularly the phase change). A 3D finite element software and a finite volume software has been used for accurate phase change simulation within mortar, and experiments conducted for validating the temperature profiles in model, as well as research on the relationship between ambient temperature and interior temperature tendencies. These data, collected throughout tested periods of different climatic scenarios, as well as those that are still being collected contribute to better numerical strategies in view of the obtained validations.

• Monitoring of active system testing (using heater as a heat source within the model) during early ages and along service life, with special regard to temperatures, internal humidity and the corresponding strains. 

• Laboratorial characterization of mechanical properties of hardened mortar, with special relevance to the development of a recently developed formulations that allows the maximum incorporation of PCM of cement-based materials. Implementation of complementary experimental techniques for assessment of the performance of the PCMs. The differential scanning calorimetry (DSC) method is also being tested for developed materials in order to determine the specific heat capacity as well as specific enthalpy of different compositions such as: pure PCM samples, cement based mortar with/without PCM.

• Further than the interest in deepening the current fields of expertise (mentioned above), several new fields of interest are arising, listed as follows:

• Research on the behaviour of paraffin PCM when encapsulated into the lightweight aggregates (LWAs), mainly in regard to the performance in de-icing conditions upon thermal effect, and to assessing the possibility of using PCM into the road materials to prevent the icing of the surface layer of the pavement structure.

• Establishment of cost-effective solutions for payback period of real scale building cases based on the hybrid PCM concept.

• Some experience about assessing thermal-structural behaviour of masonry structures coated with PCM mortar, with recourse to multi-physics approaches that contemplate temperature fields as support to stress analyses.

• Some experiences on preparation of Geopolymer mixtures based on Fly Ash with silicate sodium and hydroxide sodium activators: study of following properties: mechanical, thermal, durability, cost and etc,.