Plasters with mixed-in crystallization inhibitors: Results of a 4-year monitoring of on-site application

Salt crystallization is a major cause of weathering of mortars, including plasters and renders. In the last decade, the use of mixed-in salt crystallization inhibitors in mortars has been proposed as a solution to improve the durability of this material with respect to salt decay. Laboratory characterization and accelerated weathering tests have...

A new accelerated salt weathering test by RILEM TC 271-ASC: preliminary round robin validation

Salt crystallization is a major cause of damage in porous building materials. Accelerated salt weathering tests carried out in the laboratory are among the most common methods to assess the durability of material to salt decay. However, existing standards and recommendations for salt weathering tests have limitations in terms of effectiveness...

Effect of mixed in crystallization modifiers on the resistance of lime mortar against NaCl and Na₂SO₄ crystallization

Weathering of porous building materials caused by the crystallization of soluble salts is a ubiquitous problem in the built cultural heritage. Especially lime-based mortars are susceptible to salt decay, due to both their bimodal pore size distribution and low mechanical strength. The addition of crystallization modifiers to mortars during...

Towards a more effective and reliable salt crystallization test for porous building materials: state of the art

The durability of building materials with respect to salt crystallization is commonly determined by accelerated weathering tests, carried out in the laboratory. An effective laboratory weathering test should assess the durability and, in the case of conservation of historic buildings, the compatibility of repair materials with those existing....

Study on effective modifiers for damaging salts in mortar

The use of crystallization modifiers for the prevention or mitigation of salt crystallization damage has recently received a lot of research interest in the field of building conservation. However, the use of crystallization modifiers mixed in a lime-based mortar, is still a very new field of research. This paper summarizes the literature study...

Salt crystallization damage: How realistic are existing ageing tests?

Salt crystallization is a major cause of damage in porous building materials. Notwithstanding the extensive research in this field, the complexity of the problem has hindered the use of mathematical models for forecasting ageing and damage due to salt crystallization. Nowadays, the durability of materials with respect to salt crystallization is...

Sodium chloride damage to porous building materials

This research studied sodium chloride (NaCl) damage to porous building materials with the aim of: i) gaining a better understanding of the damage process and ii) developing an effective crystallization test. It has been definitely proven that NaCl modifies the hygric dilation of a material completely. Irreversible dilation occurs during drying...