Comportamento mecânico de um solo argiloso misturado com resíduos de construção e demolição para utilização em pavimentação

Abstract

The amount of construction and demolition waste (CDW) generated worldwide is significant, and the continued growth of this waste further aggravates the scenario of raw material waste. One of the development indicators of a country comes from the consumption of concrete/year since, so this indicator directly reflects the amount of construction works and/or existing reforms. New constructions and demolitions either uses raw materials or generates a significant amount of CDW, so there is an international trend towards reducing the use of raw materials and the generation of all kinds of waste. Research in this sense has shown the possibility of the application of CDW in pavement works, even though there are standards for the recycled aggregate use in pavements. In this research, the possibility of using CDW from a recycling plant in the municipality of Almirante Tamandaré (Metropolitan Region of Curitiba) mixed with a sedimentary clay-silt soil of the Guabirotuba Geological Formation in pavements was evaluated. In order to achieve the objectives of this research the following were performed or studied: characterization tests, Atteberg limits, chemical (pH), absorption, grain breaking, expansion and mechanical characterization (compaction, California Bearing Ratio, compressive strength, qu, tensile strength, qt, and the Resilient Modulus, RM) for both soil and soil-CDW blends. The characterization tests and limits showed soil improvement after mixing with the CDW, according to the TRB classification. The pH showed an alkalization process of the soil, indicating potential resistance gain reactions. Absorption and grain breakage tests showed the peculiarity of the aggregate used, once the CDW undergoes the compaction process, the grains suffer a decrease in their size, as well as the previous wetting of the aggregate is necessary, as there is an absorption process of the water required for better compaction. The compaction and CBR tests showed an increase in the resistance capacity due to the granulometric change of the material. The results of qu and qt demonstrated an increase in the capacity of resistance over time, allowing the acceptance of the hypothesis of existence of materials not inert in the CDW. By the RM test was found that the greater degradation of the material is generated during the compaction process and not during the application of repeated charges. The results demonstrate that it is possible to use the mixture 4 for the layer base, and the mixture 3 and 4 as the layer sub-base.