This paper intends to evaluate the feasibility of reintroducing recycled concrete aggregates in the precast industry. The mechanical properties of self-compacting concrete (SCC) with incorporation of recycled aggregates (RA) (coarse recycled aggregates (CRA) and fine recycled aggregates (FRA)) from crushed precast elements were evaluated. The goal was to evaluate the ability of producing SCC wi...

the old newsprint, as an important grade of waste papers, usually has been produced from chemicalmechanical pulp (cmp). although the effect of paper aging on different properties of recycled pulp has been investigated from long time ago; but, few studies have been observed about the effect of this phenomenon on recycling of cmp paper. in this study, accelerated aging was applied on hardwood cmp...

Objective: To compare and evaluate the shear bond strength of recycled orthodontic brackets using different methods. Materials & Method: A total of 50 extracted premolars and 50 metal brackets with a slot configuration of 0.022”x0.028” were used. All samples were divided into 5 groups with 10 samples each. Each group was further divided into 2 groups which were control group and experimental gr...

Recent scientific concerns to achieve sustainability in construction have suggested the implementation of using recycled aggregate in concrete because it has the potential to reduce the demand for extraction of natural raw materials and decrease the volume of wastes landfilled. In this respect, this study aims to investigate the suitability of using ceramic tile (CT) and ceramic sanitary (CS) w...

Given the development of construction industry and design and implementation of high rise buildings with complex sections and various geometrical forms, the use of self-compacting concretes has received the attention of construction engineers and provided great advantages. Due to the increasing air pollution in cities, governments encounter the important issue of repelling the pollutants in whi...

the use of recycled bassanite, produced from gypsum wastes, in ground improvement projects is initiated recently in japan to eliminate the huge quantities of gypsum wastes. meanwhile the use of recycled bassanite has a positive effect on the environment and economy, it has many challenges. these challenges are related to the release of fluorine more than the standard limits results in contamina...

Results: The experiment results indicate that the type of recycled aggregate and its replacement ratio have significant effects on the freezethaw performance. The cubic compressive strength of recycled aggregate concrete is overall slightly lower than that of normal concrete. After 100 freeze-thaw cycles, the compressive strength decreases and the reduction extent increases with increasing repl...

subgrade soil stabilization is one of the primary and major processes in the construction of any highway; also environmental authorities are concerned about the growing amount of polyethylene (pet) bottles produced by household sectors. this research in order to study effect of adding recycled polyester fiber on soil engineering properties, especially shear strength and california bearing ratio...

Changes of the pore structure of recycled fibers and the strength properties of papers produced by old corrugated container (OCC) recycled fibers were studied, after they were subjected to different stock preparation and papermaking processes. In this paper, the effects of beating, sizing, pressing, and drying on fiber properties were investigated, and the porous structure of fibers was analyze...