Karbonatisering i kalkputs. Hur hantverksmetoder kan påverka processen

Abstract

This thesis illustrates how the rate in which carbonation occurs in plasters with air-lime mortars can be affected by different surface structures and by the application of water as an after treatment over time. In the first part of the study, the rate of carbonation in the plaster has been examined and compared with three different surface structures. The second part of the study has examined and compared how the application of water with different intervals in two plasters has affected the carbonation rate. These studies have been carried out by applying a pH indicator (phenolphthalein) into holes drilled in the plaster with regular intervals. The indicator has shown the extent of the process by coloring the uncarbonated areas inside the plaster. Measurements have then been made from the surfaces of the plaster to the colored area and the depth recorded, those records have been compiled to make up the results. The results of the first part of the survey on how the processing of plastered surfaces affects the carbonation rate shows an indication of the most open textured of the plasters being carbonated the fastest. The other two plasters (one having a more closed surface – one having a more closed surface but slightly roughened) showed indications of being simultaneously carbonated at the final measurements. However, the slightly roughened plaster showed a greater carbonation depth faster than the more closed textured one. The results from the second part of the survey, regarding how after treatments by water application affects carbonation, indicates that both plasters being tested were equally carbonated at the final measurements and that both showed a consistent and similar depth of carbonation at previous measurements.