This project aims to upscale the results of former laboratory freezethaw
experiments to real-time field conditions. These results will help
in understanding the damaging mechanisms related to internal
freezing. Most studies of freeze-thaw risks focus either on durability
testing or on climate analysis. The big challenge is now to integrate
both approaches. Currently, several approaches to estimate the
freeze-thaw risk under real-time field conditions use arbitrary
thresholds which are not material specific. In this project, the
applicant wants to weigh more material specific thresholds, obtained
from laboratory experiments (such as degree of saturation), to the
occurrence of internal freezing and damage propagation in field
conditions. For this, he will install monitored natural stone test walls
near the existing weather stations in the area of Ghent. The test walls
will be equipped with sensors to monitor proxies for ice crystallization
(such as temperature and dilatation). Moreover, the climate files from
the weather stations are being integrated in heat-air-moisture (HAM)
simulations. As the test walls are designed so that they can be
defined in HAM simulations, this provides the possibility for a
feedback between HAM modelling and real-time field observations.
This will result in a better understanding of the freeze-thaw risk in
rocks in our different environments, including local effects such as
the urban heat island.