The ready mixed concrete supplier treated the RCA like lightweight aggregates and was able to produce concrete in a single-stage mixing process. Contractors placing the RCA concrete said the workability …

This paper examines the characteristics of recycled aggregate, resulting from of a non-exhaustive production process. This aggregate was found to contain impurities, such as crushed clay brick, crushed ceramic materials, and gypsum. The tests used to analyze this material were those recommended in the Spanish Structural Concrete …

US In the United States there is no regulatory barrier to the use of recycled concrete aggregate in structural concrete: since 1982, ASTM C33 ... Etxeberria M, Vázquez E, Marí A, Barra M (2007) Influence of amount of recycled coarse aggregates and production process on properties of recycled aggregate concrete. Cem Concr Res …

The criteria of RCA replacement ratio for the production of structural concrete set forth by various countries are summarized in Table ... Vásquez, E., & Marí, A. R. (2007). Influence of amount of recycled coarse aggregates and production process on properties of recycled aggregate concrete. Cement and Concrete Research,37, …

Several studies in the last decade have pointed out the impacts of the production of concrete based on aggregates from demolished concrete, namely recycled concrete aggregates (RCA) [6,7], and ...

Recycled aggregates and particularly, recycled concrete aggregate substantially affect the properties and mix design of concrete both at. fresh and hardened states since it is known by high ...

Construction and demolition waste (CDW) management is essential for the sustainable development of a country. Recycled concrete aggregates (RCA) manufactured from CDW can replace a significant portion of natural aggregates in concrete as per various research studies conducted. Nowadays, various alternate waste materials are being …

Aggregates are granular materials that are used with a cementing medium to form concrete or hydraulic mortar. They are key ingredients in the manufacture of concrete, mortar, and other construction materials, and are used in the construction and maintenance of structures such as highways, walkways, parking lots, airport runways and railways.

Aggregates, which account for 60 to 75 percent of the total volume of concrete, are divided into two distinct categories--fine and coarse. Fine aggregates generally consist of natural sand or crushed stone with most particles passing through a 3/8-inch sieve.

concrete made with 0% of recycled aggregate; HR25— concrete made with 25% of recycled coarse aggregate; HR50—concrete made with 50% recycled coarse ag-gregates; and HR100—concrete made with ...

Furthermore, around 32 bi tons of natural aggregate (NA) are extracted annually. In this scenario, replacing NA with recycled aggregate (RA) from C&DW and other wastes can mitigate …

Aggregate properties have a profound influence on concrete properties, and a proper understanding of these properties is mandatory to create high-quality concrete [54]. PET aggregates have several ...

The present research activity has been launched at the Federal University of Rio de Janeiro (UFRJ, Brazil) for demonstrating the feasibility of "ecological concrete" …

This article presents a comprehensive review on the use of recycled concrete aggregate (RCA) and recycled aggregate concrete (RAC) in construction, …

Although aggregates are most commonly known to be inert filler in concrete, the different properties of aggregate have a large impact on the strength, durability, workability, and economy of concrete. These different properties of aggregate allow designers and contractors the most flexibility to meet their design and construction requirements ...

processes necessary to produce aggregate materials and the sampling tech-niques required to obtain representative results. Origin Many properties of an aggregate derive from its parent rock: physical and mechanical properties such as relative density, strength, stiffness, hard-ness, permeability and pore structure, and chemical and mineral compo-

Concrete production is a highly intensive energy-consuming process and presently facing a number of challenges in reducing the carbon footprint and making it more economic. Sustainable technologies in maintaining concrete structures are proving to be a great challenge. Microbially induced carbonate precipitation (MICP) has developed as a novel …

Abstract. This chapter deals with the suitability of recycled aggregate concrete for structural applications, with emphasis on coarse recycled aggregates produced from concrete waste. The feasibility of recycled aggregate concrete has been consistently reported worldwide and technical bodies are becoming increasingly …

Recycled aggregate was made by crushing the waste concrete of laboratory test cubes and precast concrete columns. Three types of concrete mixtures were tested: concrete made entirely with natural aggregate (NAC) as a control concrete and two types of concrete made with natural fine and recycled coarse aggregate (50% and …

6.2—Definition of lightweight-aggregate concrete 6.3—Low-density concretes and associated aggregates 6.3.1—Structural lightweight concrete and associated aggregates 6.3.2—Moderate-strength lightweight concrete and associated aggregates 6.3.3—Properties Chapter 7—Recycled aggregates, p. E1-23 7.1—Introduction to …

Abstract. Concrete recycling to produce aggregates is crucial in reducing the demand for materials in the construction industry, particularly for the most widely …

Furthermore, in the actual production process, using industrial waste to manufacture aggregate often needs additional processing, which inevitably consumes energy and causes secondary pollution. ... Bin Jumaat M.Z., Bin Ahmmad R., Bahri S. Structural lightweight aggregate concrete using two types of waste from the palm oil …

To assess the effects of cement content on the properties of lightweight concretes, the. mixtures are made by three cement co ntents of 500, 420 and 350 kg/m. For the mixes, slumps were nearly 50 ...

rulemaking notices addressing the RCRA regulatory status of lightweight aggregate production wastes. 2modity Summary Lightweight aggregates are minerals, natural rock materials, rock-like products, and byproducts of manufacturing processes that are used as bulk fillers in lightweight structural concrete,

concrete, in construction, structural material consisting of a hard, chemically inert particulate substance, known as aggregate (usually sand and gravel), that is bonded together by cement and water. Among …

Aggregates are generally thought of as inert filler within a concrete mix. But a closer look reveals the major role and influence aggregate plays in the properties of both fresh and hardened concrete. Changes in gradation, maximum size, unit weight, and moisture content can all alter the character and performance of your concrete mix.

As a matter of fact, recycled concrete aggregates are mainly composed of two phases [21], [22], namely old aggregates and old mortar paste. Consequently, the standard procedure generally adopted for the design and production of ordinary concrete (i.e., with natural aggregates), cannot be applied when Recycled Aggregates Concrete …

Recycled Aggregate Concrete for Structural Use – An Overview of Technologies, Properties and Applications. Conference paper; First Online: 01 January 2011; pp 115–130; ... Influence of amount of recycled coarse aggregates and production process on properties of recycled aggregate concrete. Cem Concr Res 37(5):735–742. …

Some articles also show the feasibility of using recycled aggregate concrete in structural elements, either through reduced-scale elements at a laboratory or full-scale elements in real projects. ... Influence of amount of recycled coarse aggregates and production process on properties of recycled aggregate concrete. Cement Concr. …

A novel process for the production of angular-shaped high strength fly ash aggregates from an energetic, and environmental perspective is presented in this paper and compared with the production of natural aggregates. This study is significant because there is an increasing demand for aggregates and no published research addressing the …