Properties of pervious concrete incorporating recycled. When comparing the results of both aggregate and concrete experiments, they show that freezethaw resistance of the concrete aggregates has slight to no impact. Recycled aggregates are the materials for the future. Recycled concrete aggregate rca for infrastructure elements.
Pdf effect of recycled aggregate with glass fiber on high. Effect of recycled concrete aggregate properties on the. In designated concrete rc2025 to rc4050, rca can automatically be used at 20% of coarse aggregate mpa, 2011. The coarse recycled concrete aggregate was obtained by crushing a laboratory produced primary concrete at age of 28 days. Type nominal size mm density kgm 3 water absorption kgm 3 crushed granite. Recycled concrete aggregate rca produced from demolished pavements in three geographicallydispersed locations in washington state were used to perform tests on aggregate characteristics, fresh concrete properties, and hardened concrete properties.
Properties of selfcompacting concrete with recycled. Mechanical properties of concrete using recycled plastic. Flexural strength properties of recycled aggregate concrete. It is one of the most significant properties that distinguish recycled aggregate from raw aggregates. Recycled concrete aggregate coming from concrete tiles was used rca. In this method, recycled aggregate was heated to a temperature of 250c 482f and then the aggregates were drymixed in a pan mixture to remove the attached mortar. Mechanical and durability properties of concrete produced. Pdf properties of recycled concrete aggregate under different. A comparative analysis of the experimental results of the properties of fresh and hardened concrete with different replacement ratios of natural with recycled coarse aggregate is presented in the paper.
The compressive strength of recycled aggregate concrete was found to range between 18 and 65 mpa, and therefore a prediction equation is proposed for recycled aggregate concrete that considers the ratio and types of recycled coarse aggregates used. In 1994, in osnabruck, germany built the first apartment building constructed with. Ra is used to replace natural aggregate na as coarse aggregate in concrete mixes. The concrete mixtures incorporate either basalt or crushed limestone, aggregate sizes of 12 mm h in. Effect of recycled coarse aggregate on concrete properties. Laboratory investigations on properties of concrete made with rca. In this research, the fresh and hardened properties of concrete using recycled concrete aggregate as coarse and fine aggregates were evaluated. Evaluation of recycled concrete for use as aggregate in. The use of recycled concrete aggregate rca in concrete as partial and full replacements of natural coarse aggregate is growing interest in the construction industry, as it reduces the demand for virgin aggregate. Experimental study of compressive strength of recycled. Basic properties of concrete with recycled concrete aggregate based on available experimental evidence, the most important properties of recycled concrete aggregate rca and concrete made with recycled aggregate rac are briefly presented in this chapter.
This research was conducted with the use of recycled aggregate as modification. The use of metallurgical sludge waste or crushed or round rca to produce concrete deteriorates the consistency and does not significantly affect. On the other hand the fiber reinforced concrete of the mentioned sort can find applications in a large scale of structures, starting. The scope of study is about comparison between recycle coarse aggregate and natural aggregate in terms of.
Pdf mechanical properties of concrete with recycled coarse. As a reference aggregate, the natural one na was applied, too. Study on mechanical properties of recycled aggregate concreteibehaviour under uniaxial compression, journal of building materials, 105, 598604, 2007. Experimental evaluation of the highgrade properties of recycled.
The fra used come from demolished concrete of known properties. An investigation of mechanical properties of recycled. Moisture control of recycled aggregate is critical in producing consistent and workable concrete. The properties of crushed aggregate, which produced from recycled aggregate concrete are not discussed in the literature yet despite it could be a choice in some circumstances like in case of. The strength of aggregates do not contribute to the strength of concrete for low strength concrete. Aggregates aggregates generally occupy 65 80% of a concretes volume. Recycled concrete aggregate rca for infrastructure. In addition, the use of rca leads to a possible solution to the environmental problem caused by concrete waste and reduces the. The effects of aggregate type, size, and content on the behavior of normal and highstrength concrete, and the relationships between compressive strength, flexural strength, and fracture energy are discussed. For example, water to cement ratio of parent concrete will give an impact on water absorption capacity of recycled aggregates which is related to characteristics of. Crushed concrete aggregates properties and uses of.
In this paper, the permeability properties of fine recycled aggregate concrete are presented. Properties of recycled aggregate concrete springerlink. First effort has been made by nixon in 1977 who complied all the work on recycled aggregate carried out between 19451977 and prepared a stateof. It is generally accepted that when natural sand is used, up to 30 percent of natural crushed coarse aggregate can be replaced with coarse recycled aggregate without significantly affecting any of the mechanical properties of the concrete. The utilisation of recycled concrete aggregate rca in selfcompacting concrete scc has the potential to reduce both the environmental impact and financial cost associated with this increasingly popular concrete type. Recycled aggregate an overview sciencedirect topics. After crushing of these cubes, the maximum nominal size of recycled coarse aggregate used in mixes 2, 3 and 4 was 25 mm. Research efforts to introduce ra into the construction industry and to address their effects on properties could be classified to the following categories.
In this research, the fresh and hardened properties of concrete using recycled concrete aggregate as. Properties of recycled concrete aggregate under different. Four concrete mixes were produced using different replacement ratios, along with four different curing methods. Recycled concrete aggregates rca, mix design methods, equivalent volume ev, waste management, rca quality control. Creep and shrinkage of recycled aggregate concrete normal properties of recycled coarse aggregates are a lower density, a lower elastic modulus and a higher absorption than natural coarse aggregates. With the recycled aggregate content of 100%, the concrete compressive performance was very close to that of the control concrete due to the only one aggregate style used. The research of structural members made of recycled aggregate concrete rac was conducted from the 90s in many countries. Moreover, the rca type and properties seem to influence in the behaviour of rca concrete and thus should be accounted in the mix design. Pdf construction and demolition wastes are produced every day around the world. 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.
Similarly, the basic concrete properties like, compressive strength, workability etc. Properties of selfcompacting concrete with recycled coarse. Properties of concrete made with recycled aggregate from. Mechanical properties of recycled aggregates concrete. In this study, the behavior of the recycled plastic as aggregate in concrete has been investigated on compressive, tensile, and flexural strengths, weight reduction and workability. A study on the properties of recycled aggregate concrete. Crushed concrete aggregates also called as recycled concrete aggregates are fragments and pieces of concrete. Use of recycled aggregate in concrete can be useful for environmental protection.
The properties of the recycled aggregate and of the new concrete made from it, with nearly 100% of aggregate replacement, were tested. Properties of highworkability concrete with recycled. Properties of natural and recycled coarse aggregates. Pdf durability of recycled aggregate concrete miquel. May 05, 2016 3 properties of concrete with recycled concrete aggregates. In this study, research was conducted on the mechanical and durability characteristics of concrete using recycled aggregate, after developing. Pdf properties of recycled aggregate concrete made with recycled. As replacement amounts increase drying shrinkage and creep will increase and tensile strength and modulus. Crushed concrete aggregates properties and uses of recycled. The characteristics of aggregates impact performance of fresh and hardened. A lot of research has already been done on the mechanical properties of recycled aggregate concrete. The 28day compressive strengths of concretes with recycled aggregates were found similar to the ones obtained with natural aggregates regarding the standard curing condition. Recycled concrete aggregates in portland cement concrete. Aggregate particles have certain physical and chemical properties which make the aggregate acceptable or unacceptable for specific uses and conditions.
The work presented in this paper seeks to build on the existing knowledge in this area by. In this paper, the effects of various percentages 0%, 25%, 50%, 75%, 100% of recycled aggregate ra on compressive strength of recycled aggregate concrete rac were investigated. Present of contaminants in recycled aggregate decline strength of concrete produced with this aggregate. Aggregates are inert fillers floating in the cement paste matrix for concretes of low strength. The important properties of fresh and hardened recycled aggregate concrete such as workability, compressive strength, split tensile strength, flexural strength, modulus of elasticity, density and ultrasonic pulse velocity upv are discussed in detail in this chapter. This led to some changes in the standard for various applications. Abdus salamb, mohd zamin jumaat b, fahrol fadhli jaafar, hawa binti saadb adepartment of civil and environmental engineering, faculty of engineering, university of waterloo, 200 university avenue west, waterloo, ontario, canada n2l 3g1. Recycled concrete aggregates in portland cement concrete pavement.
Concrete mixtures were prepared by using 50% and 100% rca and. Pdf the influence of recycled concrete aggregate on the. May 14, 2015 properties of recycled aggregate concrete. Recycled concrete as aggregate for structural concrete. Durability and other concrete properties are affected by the use of recycled aggregate in concrete mixes. Pdf effect of recycled aggregate with glass fiber on. Pdf the aim of this investigation is to use coconut fibers as a reinforcing factor for concrete made of 70% natural aggregates and 30%. The basic engineering properties of recycled concrete aggregate rca is evaluated and it is compared with the normal aggregate na. Recognition of these properties and characteristics assists the technician in evaluating the different aggregates used in highway construction. Properties of concrete with recycled concrete aggregate.
These properties are due to the fact that the recycled coarse aggregates have partially adhered mortar which has. The goals of this study were to investigate the effects of substituting recycled concrete aggregate rca for natural aggregate na in concrete intended for new portland cement concrete pavements pccp, and to investigate the effects of substituting fly ash for portland cement while simultaneously substituting rca for na. Berry 4 undergraduate research assistant 5 school of engineering 6 the university of vermont 7 116 votey hall, 33 colchester ave. Range of particle sizes found in aggregate for use in concrete. Strength and durability evaluation of recycled aggregate concrete. Recycled concrete as aggregate for structural concrete production. No significant adjustment in paving operations is necessary due to the use of 100% recycled coarse and fine aggregate in concrete. Recommendations for production of rac are also presented. This method removed 70 to 80% of attached mortar of the rca. Using recycled coarse aggregate rca to replace natural pebbles and using lithium slag ls from industrial waste to replace cement in order to improve the mechanical properties of concrete and solve environmental problems. Rca is mostly being used in granular bases, embankments, sound barriers, fills, and so on. Significant differences were observed between the properties of the recycled aggregates of various particle size groups, while the crushing age had almost no effect. The application of recycled aggregate has been started in a large number of construction projects of many european, american, russian and asian countries.
There are several reasons for specifying grading limits and nominal maximum aggregate size. Residual tiles from construction site were crushed using laboratory crusher, following by sorting of 48 fraction. Strength and durability evaluation of recycled aggregate. However, to date limited research exists exploring the use of coarse rca in scc. Use of recycled concrete wastes can solve the problem of dumping of such wastes on valuable landfill and decreases the depletion of natural resources. Why use aggregate reduce the cost of the concrete 14 18 of the cement price reduce thermal cracking 100 kg of opc produces about 12oc temperature rise reduces shrinkage 10% reduction in aggregate volume can double shrinkage high aggregate. Pdf this paper presents the experimental results of a study on comparing the difference in properties of recycled aggregates ras with. A comparative between the experimental results of the properties for fresh and hardened concrete is presented in the paper. The percentages of recycled coarse aggregate to dolomite were 0. Proceedings of the international symposium organised by the concrete technology unit, university of dundee and held at the department of trade and industry conference centre, london, uk on 11 12 november 1998.
Properties of recycled concrete aggregate under different curing. Influence of recycled aggregate on concrete properties 1. An investigation of mechanical properties of recycled coarse. It appears that the selfsustained concrete with recycled aggregate obeys very restrictive material properties and can only be uses in a short range of applications. Also, in moist curing, full replacement of coarse aggregates gave the highest compressive strength at age of 28 days. Mixes with 10%, 30%, 50% and 100% by volume replacement of fine natural aggregates fna with fra were produced and tested for water. Properties of the recycled aggregate concrete scientific. Pdf mechanical properties of concrete with recycled. It was concluded that compressive strength did not seem to be affected by recycled concrete coarse aggre. In 1994, in osnabruck, germany built the first apartment building constructed with recycled aggregate concrete. Research article properties of selfcompacting concrete. Evaluation of recycled concrete for use as aggregate in new.
Use of recycled aggregates in concrete a paradigm shift. The extensive research on recycled concrete aggregate and recycled aggregate concrete rac as started from year 1945 in various part of the world after second world war, but in a fragmented manner. Aggregate strength, gradation, absorption, specific gravity, shape and texture are some of the physical and mechanical characteristics that contribute to the strength and durability of concrete. Effect of the aggregate size on strength properties of. Modulus of elasticity of recycled aggregate concrete.