Úprava stavebního odpadu a jeho využití v cementových kompozitech

Abstract

Not only in the context of environmental protection, but also in terms of raw materials policy, the recycling of waste raw materials is becoming an increasingly topical issue in the Czech Republic. The issue of recycling should be given great emphasis in view of the limited supplies of primary raw materials in the Czech Republic. The recycling of construction and demolition waste is a very topical issue, as the amount of this waste produced has long been ranked at the top. At the same time, this waste is most often taken to landfill sites where there is no longer any use for it. The issue of landfilling in the Moravian-Silesian region also concerns mining spoil. In the first stage this dissertation describes an experimental research on the possible use of construction and demolition waste in cement composites. The construction and demolition waste was divided into brick and mixtures (mixture of brick, mortar and ceramics) and crushed in 3 stages and subjected to the investigation of the proportions of individual components after each stage. Subsequently, the possibility of grinding this waste was investigated. For the first stage, a total of 16 formulations were proposed with different proportions of replacement of standard aggregate (10%, 30%, 50% and 100%) and two types of cement (Portland cement CEM I 42,5 R and Portland cement with limestone CEM II/B-LL 32,5 R). In the second stage, the work investigates the possible use of tailings as a partial replacement of construction and demolition waste. For the experimental mixing of cement composites, the formulation from the first stage with 100% replacement of standard aggregate was used. The mixed demolition recyclate was replaced by thermally active and spent demolition residue in the ratio of 20% and 50% replacement of mixed demolition recyclate. The dissertation describes the test methodologies used to determine the chemical and physical-mechanical properties of the materials, the experimental plans for both stages, the proposed formulations of the cement composites and their physical-mechanical properties and evaluation. The results of the dissertation can be used as a basis for a more detailed investigation of the possibilities for the recovery of construction and demolition waste and the recycling of post-mining tailings.