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  1. A proposal for a test procedure for injection products against rising dampIr. Yves Vanhellemont, Ing. André Pien, Belgian Building Research Institute, BrusselsDr. Hilde De Clercq, Royal Institute for Cultural Heritage, Brussels

  2. About half of the problems encountered while renovating or restoring buildings are linked to the presence of rising damp and/or the presence of salts (mostly because of the rising damp). Humidity, due to the presence of rising damp, and salts give rise to many problems (often enhanced by other influences): Aesthetical Frost damage Superficial or crypto-efflorescences Hygroscopic salts Biological damage … Introduction

  3. Capillary absorption of the masonry ‘Hiding’ of the problems by water- and vapourproof claddings or renders, do not solve the problems; on the contrary, they may become worse. Introduction

  4. Most efficient intervention is the application of a mechanical barrier, with many disadvantages…

  5. … and therefore injections of masonry are much more used in Belgium.

  6. Investigation of the product the treatment To be investigated: Identification Efficiency Migration of the product This procedure is a result of own research, experience and literature survey. Introduction

  7. The procedure should serve as a basis for technical agreements, therefore an identification procedure is nevessary, in order to control the production continuity. Density Viscosity Dry weight: a measure for the concentration of active compound FT-IR: determination of the absorption spectrum (active compound AND solvent) Identification

  8. Most logic (and inspired by other existing procedures, i.e. WTA, BBA, …) is measuring the efficiency using masonry wallets. Substrates

  9. BUT: because of reasons related to time and costs, another small-scale test is proposed, using small prism-shaped, fully carbonated, mortar-samples (composed of hydrated lime, cement and sand) 8cm 16cm 4cm Substrates

  10. Sample preparation Capillary behaviour Pre-conditioning Application of the product Capillary behaviour after treatment Migration of the product Overview

  11. Capillary suction according to EN 1925 (two weeks: saturation moisture content) Drying of the samples (45°C) Pre-conditioning of the samples with a salt solution, containing NaCl, KNO3, Na2SO4, to saturation degrees of 60, 80 and 95 % Waiting for one week Application of the product (1/4th of the normal quantity) Waiting for 28 days Capillary absorption test according to EN 1925 untill constant mass Afterwards: determination of the capillary water content (taking into account the hygroscopic moisture content of the samples!) Efficiency test

  12. Cutting the sample in 2 Drying of the sample (45°C) Wetting of the surface: distinction between zones where water is or isn’t absorbed gives an indication of the migration abilities of the product Migration of the product

  13. Rising damp is a major cause of different kinds of damage to historic buildings. Many interventions have been designed, although (at least in Belgium) injections against rising damp seem to be the most flexible and rapid and widely-used intervention. In order to make the right choice for an injection product, and to stimulate the industry of developping even better products, a test procedure for testing such products, is important. The procedure is a compromise between scientific, economic and time-related issues. An initial test-phase, where also well-known products (both good and bad) are being tested. If this procedure gives rise to usefull results, these will serve as a basis for (Belgian) technical agreements. The procedure may also be proposed to (for instance) the CEN TC 346 « conservation of cultural property » (in which both BBRI and KIK/IRPA take place) Conclusion