The Influence of Fine Sand from Construction-Demolition Wastes (CDW) in the Mortar Properties

2014 ◽  
Vol 600 ◽  
pp. 357-366 ◽  
Author(s):  
Lidiane Fernanda Jochem ◽  
Janaíde Cavalcante Rocha ◽  
Malik Cheriaf
Keyword(s):  
Fine Fraction ◽  
Fine Sand ◽  
Construction And Demolition Waste ◽  
Recycled Aggregate ◽  
Recycled Aggregates ◽  
Capillary Absorption ◽  
Fine Aggregate ◽  
Demolition Waste ◽  
Natural Sand ◽  
Hardened State

A fine fraction of recycled aggregates from the processing of construction and demolition waste (CDW), have a very effective potential use in mortar as a partial fine aggregate replacement for natural sand, an also contribute to the development of sustainable materials, specifically to produce coating mortar. This paper presents the results of a study using recycled aggregate in mortar as a replacement for natural sand, analyzing the effects of pre-wetting and the performance in mortar composition with a fine sand (1.2/ 0.15 mm). In this study was investigated the behavior of recycled aggregate dry and wet previously until to saturated surface dry condition (reaching this value by capillary absorption test of the granulometric prepared curve). Five different compositions have been defined, varying the quantity of fine and determined the physical properties of recycled aggregate. Then the mortars were prepared and evaluated in the fresh state: specific gravity, water retention and workability, and in the hardened state: hygrothermal and mechanical properties. The results showed that the wetting of the aggregate affects the properties of the mortar, as well the addition of fines. There is an advantage when is realized wetting of the recycled aggregate CDW. The addition of fine in mortars must be controlled, and the fine aggregates improved the almost properties and in excess can reduce the hygrothermals properties.

The Properties of Fine Recycled Aggregate Concrete Containing Recycled Bricks from Construction and Demolition Waste

2018 ◽  
Vol 760 ◽  
pp. 193-198 ◽  
Author(s):  
Kristina Fořtová ◽  
Tereza Pavlů
Keyword(s):  
Recycled Aggregate Concrete ◽  
Construction And Demolition Waste ◽  
Recycled Aggregate ◽  
Partial Replacement ◽  
Fine Aggregate ◽  
Demolition Waste ◽  
Natural Sand ◽  
Aggregate Concrete ◽  
Freeze Thaw ◽  
Recycled Fine Aggregate

This paper presents research results of recycled fine aggregate concrete testing. The main aim of this contribution is verification of properties of fine aggregate concrete with partial replacement of fine natural aggregate by recycled masonry aggregate originated from construction and demolition waste. The influence of partial replacement of natural sand to mechanical properties and freeze-thaw resistance is described. The compressive strength and flexural strength were tested at the age of 28 and 60 days and after 25, 50, 75 and 100 freeze-thaw cycles. Partial replacement of natural sand was 0, 25 and 50 % for all these tests. Prismatic specimens were examined.

scholarly journals Preliminary Analysis of the Use of Construction Waste to Replace Conventional Aggregates in Concrete

Buildings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 81
Author(s):  
Fernando A. N. Silva ◽  
João M. P. Q. Delgado ◽  
António C. Azevedo ◽  
António G. B. Lima ◽  
Castorina S. Vieira
Keyword(s):  
Compressive Strength ◽  
Coarse Aggregate ◽  
Recycled Aggregate Concrete ◽  
Construction And Demolition Waste ◽  
Recycled Aggregate ◽  
Recycled Aggregates ◽  
Fine Aggregate ◽  
Demolition Waste ◽  
Fine Aggregates ◽  
Mechanical Strengths

This work aims to study the influence of using construction and demolition waste in the replacement of coarse and fine aggregate to produce recycled aggregate concrete (RAC). A moderate compressive strength concrete made with usual fine and coarse aggregate was used as a benchmark material. Compressive and split tensile tests were performed using 120 cylindrical concrete specimens with 150 mm diameter and 300 mm length. Four-point flexural tests in reinforced beams made with conventional concrete and RAC were performed. The results obtained showed that the use of recycled fine aggregates, in both percentages of substitution investigated—50% and 100%— did not generate any deleterious influence on the values of compressive strength and split tensile strength of the RACs produced. Tin fact, the mechanical strengths of RACs produced with recycled fine aggregate were equal or higher than those from the reference concrete. The same behavior was not observed, however, when the recycled coarse aggregate was used. For this case, decreases in concrete mechanical strengths were observed, especially in compressive strength, with values around 35% lower when compared to the reference concrete. Tensile mechanical tests results confirmed the excellent behavior of all RACs made with replacement of usual fine aggregates by recycled. Bending tests performed in reinforced RAC beams had as objective to evaluate the deformation profile of the beams. The obtained results showed that RAC beams with full replacement of usual fine aggregate by the recycled aggregates have presented little changes in the global behavior, an aspect that encourages its use.

scholarly journals Construction and Demolition Waste As Recycled Aggregate for Environmentally-Friendly Concrete Paving.

2021 ◽  
Author(s):  
Manuel Contreras Llanes ◽  
Maximina Romero Pérez ◽  
Manuel Jesús Gázquez González ◽  
Juan Pedro Bolívar Raya
Keyword(s):  
Tensile Strength ◽  
Reference Sample ◽  
Production Costs ◽  
Construction And Demolition Waste ◽  
Recycled Aggregate ◽  
Recycled Aggregates ◽  
Demolition Waste ◽  
Natural Sand ◽  
Natural Aggregates ◽  
Sand And Gravel

Abstract Recycled aggregates (RA) from construction and demolition waste (CDW) instead of natural aggregates (NA) was analysed in the manufacture of new eco-friendly concrete. Fine (FRA) and coarse (CRA) recycled aggregates were used in different percentages as substitutes of natural sand and gravel, respectively. The results revealed that the use of RA in percentages of up to 50 wt.% are feasible. Additionally, RA were used to produce paving blocks in accordance with industrial requirements. Thus, values of water absorption lesser than 6% and tensile strength upper than 3.6 MPa were obtained, which are similar to those of a reference sample. These results were achieved by reducing the incorporation of cement, thereby saving production costs and minimizing environmental impact.

Stress-Strain Behavior of Mortar Mixtures Containing Construction and Demolition Waste as Fine Aggregate

2014 ◽  
Vol 634 ◽  
pp. 300-306 ◽  
Author(s):  
Juliana C. Ferreira ◽  
Thiago M. Grabois ◽  
Gabrielle C.S. Calcado ◽  
Romildo D. Toledo Filho
Keyword(s):  
Mechanical Response ◽  
Construction And Demolition Waste ◽  
University Hospital ◽  
Recycled Aggregate ◽  
Fine Aggregate ◽  
Demolition Waste ◽  
Stress Strain ◽  
Natural Sand ◽  
Strain Behavior ◽  
Recycled Fine Aggregate

In this paper it was investigated how the use of recycled fine aggregate influences the stress-strain behavior of mortar mixtures with different strengths. The mix design composition of the studied mortars, expressed by mass, were 1:2:0.45, 1:4:0.68 and 1:6:1.05 (cement: sand: water/cement ratio). The substitution percentages by mass of the natural aggregate by recycled aggregate were 15, 25 and 50%. The recycled aggregate had a grain size distribution comparable to that of natural sand and was obtained by grinding the waste produced by the partial demolition of UFRJ’s University Hospital. The mortars were evaluated under uniaxial compressive strength test after 28 days of curing. The results indicated that for the two higher strength classes the substitution rates affects its mechanical response by decreasing the strength. Besides, for the lower strength class the recycled aggregate could promote an increase of strength in the case of 25% of replacement.

scholarly journals Reduction of the Cement Content by Incorporation of Fine Recycled Aggregates from Construction and Demolition Waste in Rendering Mortars

2021 ◽  
Vol 6 (1) ◽  
pp. 11
Author(s):  
Sara Jesus ◽  
Cinthia Maia Pederneiras ◽  
Catarina Brazão Farinha ◽  
Jorge de Brito ◽  
Rosário Veiga
Keyword(s):  
Cement Content ◽  
Construction Materials ◽  
Recycled Concrete ◽  
Construction And Demolition Waste ◽  
Recycled Aggregate ◽  
Recycled Aggregates ◽  
Concrete Aggregate ◽  
Demolition Waste ◽  
Construction And Demolition Wastes ◽  
Hardened State

The construction sector is responsible for one third of the total wastes produced in the EU. Finding solutions for the reuse or recycling of these wastes is one of the major environmental concerns of modern times. The replacement of sand or cement in specific construction materials, such as concrete or mortars, is a possible solution for these wastes’ management. By using construction and demolition wastes in construction materials, namely on buildings, the cycle of circular economy is closed, increasing the life cycle of the wastes in the same sector. In this research, a reduction of cement content in rendering mortars is analysed. This reduction is achieved by a decrease of the cement/aggregate ratio simultaneously with the incorporation of very fine recycled aggregate from construction and demolition waste. Two recycled aggregates were studied: recycled concrete aggregate (RCA) and mixed recycled aggregate (MRA). The fresh and hardened state properties of the mortars were analysed. Several tests were carried out to evaluate the mortars’ performance, such as mechanical strength tests, water absorption tests, drying tests and shrinkage. It was noticed that the incorporation of RCA led to a better behaviour than in the reference mortar, in terms of mechanical strengths and protection against water.

Applicability of recycled aggregates in concrete piles for soft soil improvement

2016 ◽  
Vol 35 (1) ◽  
pp. 56-64 ◽  
Author(s):  
Ronaldo A Medeiros-Junior ◽  
Carlos ET Balestra ◽  
Maryangela G Lima
Keyword(s):  
Compressive Strength ◽  
Bearing Capacity ◽  
Soft Soil ◽  
Construction And Demolition Waste ◽  
Recycled Aggregate ◽  
Recycled Aggregates ◽  
Fine Aggregate ◽  
Demolition Waste ◽  
Soft Soils ◽  
Natural Aggregates

The expressive generation of construction and demolition waste is stimulating several studies for reusing this material. The improvement of soft soils by concrete compaction piles has been widely applied for 40 years in some Brazilian cities. This technique is used to improve the bearing capacity of soft soils, allowing executing shallow foundations instead of deep foundations. The compaction piles use a high volume of material. This article explored the possibility of using recycled aggregates from construction waste to replace the natural aggregates in order to improve the bearing capacity of the soft soil, regarding its compressive strength. Construction wastes from different stages of a construction were used in order to make samples of concrete with recycled aggregates. The strength of concretes with natural aggregates was compared with the strength of concretes with recycled (fine and coarse) aggregates. Results show that all samples met the minimum compressive strength specified for compaction piles used to improve the bearing capacity of soft soils. The concrete with recycled aggregate from the structural stage had even higher resistances than the concrete with natural aggregates. This behaviour was attributed to the large amount of cementitious materials in the composition of this type of concrete. It was also observed that concrete with recycled fine aggregate has a superior resistance to concrete with recycled coarse aggregate.

scholarly journals Construction and demolition waste as recycled aggregate for environmentally friendly concrete paving

2021 ◽  
Author(s):  
Manuel Contreras Llanes ◽  
Maximina Romero Pérez ◽  
Manuel Jesús Gázquez González ◽  
Juan Pedro Bolívar Raya
Keyword(s):  
Reference Sample ◽  
Production Costs ◽  
Construction And Demolition Waste ◽  
Recycled Aggregate ◽  
Recycled Aggregates ◽  
Demolition Waste ◽  
Natural Sand ◽  
Limit Values ◽  
Natural Aggregates ◽  
Sand And Gravel

AbstractRecycled aggregates (RA) from construction and demolition waste (CDW) instead of natural aggregates (NA) were analysed in the manufacture of new eco-friendly concrete. Fine (FRA) and coarse (CRA) recycled aggregates were used in different percentages as substitutes of natural sand and gravel, respectively. The results revealed that the use of RA in percentages of up to 50 wt.% is feasible. Additionally, RA were used to produce paving blocks in accordance with industrial requirements. Thus, values of water absorption lesser than 6.0% and tensile strength upper than 3.6 MPa were obtained, which are similar to those of a reference sample and within the limit values established by the regulations. These results were achieved by reducing the incorporation of cement, thereby saving production costs and minimizing environmental impact.

Concrete Production of Hot Asphalt Using Recycled Aggregates CDW

2016 ◽  
Vol 881 ◽  
pp. 346-350 ◽  
Author(s):  
Luzana Leite Brasileiro ◽  
Fátima Maria de Souza Pereira ◽  
Pablo de Abreu Vieira ◽  
José Milton Elias de Matos
Keyword(s):  
Solid Waste ◽  
National Policy ◽  
Mechanical Tests ◽  
Construction And Demolition Waste ◽  
Recycled Aggregate ◽  
Recycled Aggregates ◽  
Demolition Waste ◽  
Final Destination ◽  
Natural Aggregate ◽  
Concrete Production

Every year, there is a considerable increase in the exploitation of deposits to supply the market for aggregates. On the other hand, so does the production of solid waste from construction and demolition waste (CDW). In 2010 Brazil approved the PNRS (National Policy on Solid Waste), which sets out how the country should have their waste, encouraging recycling and sustainability. As an alternative to the above problem, this paper aims to investigate the feasibility of partial and total replacement of the asphalt concrete aggregates by recycled aggregates from CDW in order to reduce the environmental impacts caused by the operation of quarries and give an adequate final destination the residue produced by man in construction. Were carried out five (05) projects mixture of: the first (parameter of our research) used only natural aggregates (0% CDW) in the second, third and fourth replaced 25%, 50% and 75% respectively of natural aggregate by the recycled aggregate and the fifth and last, used only recycled aggregates (100% CDW). They carried out the characterization of the aggregates by means of physico-chemical and mechanical, analyzing them with reference based on specific standards paving. For mixtures, they calculated the volumetric parameters and performed mechanical tests of tensile strength and stability. The results indicate that the recycled aggregate, in a defined proportion, can replace the natural aggregate in the flexible pavements

scholarly journals Effects of Recycled Aggregate Resin (RAR) in Concrete Material

2020 ◽  
Vol 11 (2) ◽  
Author(s):  
Sharifah Salwa Mohd Zuki ◽  
◽  
Shahiron Shahidan ◽  
Shivaraj Subramaniam ◽  
◽  
...  
Keyword(s):  
Epoxy Resin ◽  
Recycled Aggregate Concrete ◽  
Construction And Demolition Waste ◽  
Recycled Aggregate ◽  
Engineering Properties ◽  
Recycled Aggregates ◽  
Hardened Concrete ◽  
Demolition Waste ◽  
Split Tensile Strength ◽  
Close Proximity

This paper discussed the recycled aggregates produced from construction and demolition waste and their utilization in concrete construction. Along with a brief overview of the engineering properties of recycled aggregates, the paper also summarizes the effect and use of recycled aggregates on the properties of fresh and hardened concrete. The recycled aggregates were treated with epoxy resin to reduce the water absorptions with different percentages of resin such as 0%, 25%, 50%, 75%, and 100%. Epoxy resin is widely used in recent years owing to the enhancing of mechanical and durability of the concrete. This research also showed, recycled aggregate concrete are close proximity to normal concrete in terms of split tensile strength, compression strength and wet density. The low usage of resin was obtained good strength concrete compared to high percentage contained treated aggregates due to low bonding between material.

scholarly journals Incorporation of recycled aggregates from construction and demolition waste in paver blocks

2020 ◽  
Vol 13 (4) ◽  
Author(s):  
Cinthia Maia Pederneiras ◽  
Maria Del Pilar Durante ◽  
Ênio Fernandes Amorim ◽  
Ruan Landolfo da Silva Ferreira
Keyword(s):  
Natural Resources ◽  
Mechanical Strength ◽  
Reference Sample ◽  
Construction And Demolition Waste ◽  
Recycled Aggregates ◽  
World Population ◽  
Fine Aggregate ◽  
Demolition Waste ◽  
Concrete Blocks ◽  
Modified Block

ABSTRACT: The consumption of natural resources and energy increased proportionally with the growth of the world population and its economic level. There was an increasing exponential consumption of natural resources, which implied an increase in environmental impacts. The construction sector is responsible for a very significant production of construction and demolition waste (CDW). Thus, there is a concern in search of a more sustainable final disposal. Many studies have been investigated the development of new materials with the incorporation of recycled aggregates from CDW. This paper presents a study of performance evaluation of concrete blocks produced with CDW. For that purpose, an experimental campaign was performed, including a characterization of the aggregates used. The incorporation of 100% of fine and coarse recycled aggregates. The mixtures were designed according to the condition of the aggregate (dry, washed or saturated). The performance of these blocks was evaluated in terms of mechanical strength and water absorption. Some additional tests were also performed to deeper analyze of the microstructure of these blocks. To assess the durability of the concrete blocks, a full-scale road was built. The results were very positive, since there were no significant differences between the modified concrete blocks and the reference sample (0% of the CDW). The modified block with fine aggregate presented the best performance of all the blocks, concerning mechanical strength. In addition, the performance of concrete blocks with washed recycled aggregates had a better performance compared to the others. The results obtained were satisfactory for the application of the blocks in the streets with low movement and low load.

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