RECOMMENDATIONS FOR RECYCLING, PROCESSING AND REUSE OF CONCRETE

摘要

Some countries started to recycle concrete materials for reuse in structural or other issues. Some of them, like Germany, Australia and Canada have established their own recommendation guide for recycling concrete [1,2]. The recycling consists of crushing old concrete into aggregates, and then processing it into new mixture using recycled aggregates with specified sizes [3,4]. The aim of this recycling is to save nature from deforestation and dryness, by reducing the need to gravel and so the quarries work, and also to economize the waste management [5,6]. The present research work consists of an experimental study assessing the impact of using recycled aggregates on the concrete behavior and on the country's economy. We are especially interested in determining the best composition for the new mixture of concrete resulting from reusing different types of recycled aggregates. Different types of tests have been done depending on the aggregates sizes, their origin and their state (burned or safe). The analysis is based on the comparison between compressive strength, water-cement ratio, slump, porosity and durability. Otherwise, the impact on economy is analyzed, a priori, by studying the effect of reducing the cost of the resulting concrete on construction spending. The resulted recommendations indicate the sizes of aggregates which may constitute the best composition for recycling and processing concrete, and the best use for each type of concrete depending on behavior and economy effect.