Østerby, C.B.

This Bachelor Thesis examines the possibility of utilizing glass insulation waste in bricks. The project is of experimental nature, expressed through laboratory investigations of the properties of brick and glass wool. Furthermore, the project discusses the potential of glass wool as a waste product, that can be part of a circular value chain where it is recycled as a valuable resource.

Wastes are a significant resource that can be an important part of the work to reduce the building’s resource consumption and environmental impact. In spite of this, 4 % annually is landfilled, corresponding to approx. 450 thousand tons of Denmarks total waste production. The use of glass wool in bricks is an example of utilizing a waste for value creation.

Glass wool waste was added in bricks up to 15 wt-% in two studies using different sampletsizes; pill and cube samples - both types of samples burned at 1000 oC.

First, pellets samples were produced and tested to assess the possibility of interfering with glass wool and the immediate properties of the material. The pellets was subsequently measured and weighed on properties such as shrinkage, density and porosity. Based on the test results for the pellet samples, three cube samples were produced for each percentage of 0% - 5% - 10% - 15%, respektively. The cubes were formed under a pressure of 4 kN and dried by a custom program to avoid drying cracks. Subsequently, all samples were measured and weighted on properties such as shrinkage, density, porosity, capillary suction (water absorption) and compressive strength.

The addition of glass wool resulted in reduced drying shrinkage, which can have a particularly beneficial effect on the production and spillage of bricks, and possibly contribute to new design of the material. The bricks visual character also gradually changes with glass wool - as the surface becomes rougher and colour tinted green. Density is reduced and porosity increased by using glass wool, and at the expense of this the water absorption increases while the compressive strength reduces.

Based on the experimental results found, it is concluded that the use of glass wool, as a pore-forming agent in bricks, shows promising properties and suggests new relevant experiments that can further help determine the opportunities of glass wool as additive in bricks.

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