An in-situ monitoring system for natural temperature and relative humidity

Abstract

Oxidation of pyrite-rich, carbonaceous mudrocks used as fill beneath ground bearing floor slabs is currently causing significant problems to domestic and other properties in Ireland. Due to the precipitation of gypsum and other minerals the fill expands and this causes heave of slabs, together with distortion and cracking of the structure. Temperature is known to have an effect on both the rate and amount of this expansion; however, the full impact of human habitation on this process is not fully understood. The paper gives details of the development and testing of a system for monitoring temperature, humidity and pressure conditions within the material. This system is designed to minimise cost and disruption to the homeowner, whilst facilitating reliable measurements over period of 3 to 12 months.

Laboratory foundation model with pyrite-bearing mudstone fill

“…In relation to (i), Taylor et al (2013) report a similar experience of limited range of usability of humidity sensors in pyrite-bearing fill, albeit at a lower limiting moisture content. In keeping with (ii), Jiang and Yuan (2013) also established that the relationship between the relative humidity of an air pocket in a concrete cube sample and the moisture content was non-linear.…”