Building Materials from Waste

Abstract

In Germany, about 60 million tons of demolition waste are generated annually. Approximately 70% of the demolition waste is currently recycled. Most recycling applications, for example in roadbed substructures, can be seen as a kind of downcycling. However, there are also some high-level applications for demolition waste. For instance, crushed and sieved concrete demolition waste can be used as concrete aggregate instead of natural materials. Depending on the crushing process, about a third of the broken concrete is currently concrete sand. At present, concrete sand fraction (0-4 mm) is rarely reused as a concrete aggregate. This is due to the fact that some important characteristics of crushed concrete sand are different from those of natural sand. As a result, it does not reach the standards required for aggregates. Concrete containing such aggregate is of lower quality than concrete made of natural aggregate. This paper describes an experimental investigation on the treatment of concrete sand gained from demolition waste by wet processing using a jig whereby the sand is separated by grain size and, more importantly, by density. Concrete produced with concrete sand which has been treated in this manner should have the same quality as concrete prepared with natural aggregate. Recycled sand used as aggregate substitutes natural resources and avoids disposal of waste. It has all the characteristics of an Ecomaterial.

Kinetic and calorimetric study of the adsorption of dyes on mesoporous activated carbon prepared from coconut coir dust

“…To overcome this problem, one option is to develop a chemical industry based on the use of this kind of abundant raw material [2]. Biomass is widely used as an alternative energy source [3][4][5][6], but its use as a precursor of several different products has also been described elsewhere [7].…”

Recycling Fine Aggregate from Demolished Hollow Concrete Block for Green Concrete in Ethiopia

“…Although it's possible in many countries to estimate the amount of demolitions waste expected from a given site, this is not yet a common practice in Ethiopia. For example, in the European Union (EU), about 850 million tons of construction and demolition wastes are generated annually [12], but no record was available for the amount of C&D wastes in Ethiopia due to lack of tracking the solid waste disposal.…”

Mechanical Properties of Lightweight Concrete Containing Melamine Formaldehyde Waste Using Full Factorial Design

“…It also helps eliminating waste plastic and add value to the waste. 8) Therefore, this research aim to the investigation of the utilization of melamine formaldehyde waste (MFW) as a fine aggregate in lightweight concrete was investigated. The analysis of mechanical properties of lightweight concrete containing MFW was done by using 2 k factorial design and ensured that the compressive strength and water absorption results are within the Thai Industrial Standards.…”