Influence of origin and year of harvest on the performance of pith mortars

Abstract

The plant aggregates used for the production of bio-based mortars and concretes, present a natural variability due to their geographical origin, climatic conditions and the year of harvest. This variability might be a problem for the promotion of such materials if it significantly impacts the performance of the final product. To investigate such influence, five pith aggregates of the same kind but from different regions in France were used to prepare bio-based mortars. The impact on the mechanical performance have been evaluated through unconfined compression test. Hot wire thermal conductivity, moisture adsorption/desorption isotherm, moisture permeability and Moisture Buffer Value (MBV) tests were used to evaluate the hygrothermal behaviour. Results show no major difference in the mechanical resistance of the pith mortar, in fact the drying procedure showed to have a stronger influence. Only slender differences were observed for hygrothermal properties.