Cultrone,G. and Sebastian(後のaの頭に´),E.(2008): Laboratory simulation showing the influence of salt efflorescence on the weathering of composite building materials. Environ.Geol., 56, 729-740.

『合成建材の風化に対する塩風解の影響を示す実験室シミュレーション』


Abstract
 A common decay scenario in old and new buildings was simulated: the effects on masonry structures of salt efflorescence or subefflorescence produced by the rise of saline solution. Eight different types of masonry wall each made up of a combination of different construction materials (brick, calcarenite and four types of mortar were combined as follows: pure lime mortar, mortar + air entraining agent, mortar + pozzolana, mortar + air entraining agent + pozzolana) have been tested. These materials have different textures (strong anisotropy in brick, irregular-shaped pores in calcarenite, retraction fissures or rounded pores in mortars which also show a reduction of porosity along the contact area with the stone), different hydric behaviours (under total immersion brick + mortar specimens absorb water faster than calcarenite + mortar specimens) and different pore size distribution (brick shows unimodal pore distribution, whereas calcarenite and mortars are bimodal). In the salt weathering test, mortars interlayered with masonry blocks did not act as sacrificial layers. In fact, they allowed salts to rise through them and crystallize on the brick or calcarenite pieces causing the masonry structure to decay. Only the addition of an air-entraining agent partially hindered the capillary rise of the salt-laden solutions.

Keywords: Masonry walls; Efflorescence and subefflorescence; Porosity; Weathering』

Introduction
Materials
Methods
Results and discussions
 Optical microscopy
  Brick and calcarenite
  Mortars
 Hydric tests
 FESEM observations
 Salt crystallization test
 Changes in masonry texture after simulated weathering test
Conclusion
Acknowledgments
References


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