Mathematical modelling of the water absorption properties for historical lime-based mortars from Catania (Sicily, Italy)

TL;DR

This paper develops a mathematical model to describe the water absorption and permeability of historic lime-based mortars using volcanic aggregates, validated against experimental data from Catania, Italy.

Contribution

It introduces a calibrated numerical model for capillary pressure and permeability in lime mortars with volcanic aggregates, validated through experimental comparison.

Findings

Successfully reproduces experimental retention curves

Model accurately predicts water absorption behavior

Applicable to historic lime-based mortars with volcanic aggregates

Abstract

In this paper we propose a mathematical model of the capillary and permeability properties of lime-based mortars from the historic built heritage of Catania (Sicily, Italy) produced by using two different types of volcanic aggregate, i.e. ghiara and azolo. In order to find a formulation for the capillary pressure and the permeability as functions of the saturation level inside the porous medium we calibrate the numerical algorithm against imbibition data. The validation of the mathematical model was done by comparing the experimental retention curve with the one obtained by the simulation algorithm. Indeed, with the proposed approach it was possible to reproduce the main features of the experimentally observed phenomenon for both materials.