Growth and Dissolution of Crystal under Load: New Experimental Results on KCl

Abstract

From the first experiments of Lavalle in 1853, it has been concluded, following Taber and Correns's publications, that a growing crystal can exert a linear pressure. This pressure has long been accounted for the stone degradation by salt crystal, as observed on cultural heritage objects. Nevertheless, according to both Riecke's principle and crystal growth theories, a mechanically constrained crystal has a higher solubility than an unstressed one; since the local supersaturation is reduced, the loaded faces may dissolve whereas the crystal still grows along the unloaded faces. In view of these contradictory predictions, we performed new experiments of loaded KCl crystal growth under strictly controlled conditions, with accurate measurement devices. We show that (1) the loaded crystal immersed in a slightly supersaturated solution dissolves along the loaded faces and grows along the unloaded ones, (2) the dissolution rate depends on the topology of the loaded face, and (3) the crystal is not able to grow against any applied pressure nor to develop any "crystallization pressure". These results verify Riecke's principle and contradict Taber's and Correns conclusions and related experiments. Therefore we also discuss the artifacts which were identified during our experiments and have not been monitored in these reference works.

Creep and relaxation of cement paste caused by stress‐induced dissolution of hydrated solid components

“…that precipitation preferentially occurs on unstressed surfaces). However, experiments have indicated that, for example, for uniaxially loaded crystals, dissolution will occur near the axial load application and reprecipitate along the traction‐free transverse surfaces on the same, stressed crystal. For a crystal with a smooth loading surface, one may readily show that the axial stress is the same directly under the load application (where dissolution is observed) and along the traction‐free transverse surfaces (where precipitation is observed).…”

Molecular Crystallization Inhibitors for Salt Damage Control in Porous Materials: An Overview

“…It is generally accepted that material damage occurs when the tensile stress caused by the crystals growing in the confined space of the porous matrix exerts a pressure that is greater than the tensile strength of the porous material [32][33][34][35][36].…”

“…The ability of salt to induce damage relies more specifically on the presence (at least temporary) of a supersaturated solution, and ultimately a layer (δ), between the pore walls and the crystal formation, which enables the diffusion of ions contributing to the continued growing crystal surfaces [32][33][34][35][36] ( Figure 2). The solution layer is provided by the action of repulsive forces, or "disjoining pressure", between the growing salt crystal and the pore wall.…”

Predicting salt damage in practice: A theoretical insight into laboratory tests.

“…This and experimental shortcomings raised [19,20] -as well as the failure of other researchers to directly measure crystallization pressure [21,22] -led to questioning the concept altogether. More recently, Desarnaud et al [23] used a novel experimental approach to directly quantify the crystallization pressure.…”