Aggregates are divided into two categories from the consideration of size i coarse aggregate and ii fine aggregate. Effects of aggregate types on thermal properties of concrete milon k. The voids between the coarse aggregate are filled up by fine aggregate. Coarse aggregate was then replaced with cs in 10 m2, 15 m3, 20 m4 percentages to study effect of cs replacement. Difference between fine and coarse aggregate civil.
The fine and coarse aggregates generally occupy 60% to 75% of the concrete volume 70% to 85% by mass and strongly influ ence the concretes freshly mixed and hardened proper ties, mixture proportions, and economy. All clsm mixtures were tested for flow, bleedwater, settlement, shrinkage and cracking, setting characteristics, density, compressive strength, and permeability. The natural fine aggregate nf was river sand and the physical properties are presented in table 1. What is the difference between fine aggregate and coarse. Coarse aggregate acts as inert filler material for concrete. Aggregate may be natural, manufactured or recycled natural aggregate aggregate from mineral sources which has been subjected to nothing more than mechanical processing allin aggregate aggregate consisting of a mixture of coarse and fine aggregates. The elongation index is the total weight of the material. The surface area of coarse aggregate is less than fine aggregates. An investigation into the use of manufactured sand as a. The grading is determined in accordance with astm c. Most commonlyused fine aggregates are sand pit orquarry sand, river sand and sea sandand crushed stone in powdered form,how ever. It is sometimes found that a fine aggregate which lies in one grading zone and near the border. Most natural mineral aggregates, such as sand and gravel, have a bulk density of 1520 to 1680 kgcum.
Aggregate aggregate is a broad category of coarse particulate material used in construction, including sand, gravel, crushed stone, slag, recycled concrete and geosynthetic aggregates. In order to minimize the wear in high traffic areas. For a good concrete mix, aggregates need to be clean, hard, strong particles free of absorbed chemicals or coatings of clay and other fine materials that could cause the. Section 3 presents the fresh and hardened concrete test results in combination with the fine aggregate characterization results and uses these to evaluate the properties that make manufactured sand suitable for concrete applications. Influence of waste clay bricks as fine aggregate on the. All aggregates must be essentially free of silt size 60 2 m andor organic matter. Aggregates consisting of materials that can react with alkalies in cement and cause excessive expansion, cracking and. Aggregates come in various shapes, sizes, and materials ranging from fine particles of sand to large, coarse rocks.
Fine recycled aggregate was not considered for rac production because its application in structural concrete is generally not recommended 36. The physical properties of aggregates stem from the inherent properties of the source rock. The following tests are required for basic understanding of aggregate properties. Aggregates occupy 70 to 80 % of total volume of concrete. Aggregate sampling aashto t 2 sample preparation aashto t 248 aggregate gradation of both fine and coarse aggregates aashto t 27 wash loss determination of minus no. Pdf properties of concrete with crumb rubber replacing. Measuring workability properties of aggregates also has effect on resulting concrete.
The test results on the engineering properties of scoria revealed that the material is suitable to be used as a fine aggregate in concrete production. Gradation and physical characteristics of fine aggregates. Suitability of scoria as fine aggregate and its effect on. Properties of aggregates approximately 75% of the volume of concrete is occupied by aggregates, so quality of aggregates plays an important role in determining properties of concrete. Natural river sand which is one of the constituents used in the production of conventional concrete has become highly expensive and also. Construction aggregate, or simply aggregate, is a broad category of coarse to mediumgrained particulate material used in construction, including sand, gravel, crushed stone, slag, recycled concrete and geosynthetic aggregates. Aggregates are inert granular materials such as sand, gravel, or crushed stone that, along with water and portland cement, are an essential ingredient in concrete. Rashid, debashis mallick and tozammel haque department of civil engineering, khulna university of engineering and technology, khulna, bangladesh email. In this study, the crushed stone as coarse aggregate mainly constituted of limestone, as well as possessed the consecutive gradation of 520 mm, the water absorption of 0. Based on global usage it is placed at second position after water. Table 1 limits for deleterious substances in fine aggregate for concrete, astm c 33. Aggregates types of aggregates coarse aggregate, fine.
Aggregate is classified as two different types, coarse and fine. Aggregates are chemically inert, solid bodies held together by the cement. Aggregates are divided into 3 categories based on particle size. Specific gravity and water absorption of fine aggregate by pycnometer duration. The properties of the rock, from which the aggregates are formed, depend on the properties of. It also presents the selection and justification of the fine aggregate characterisation tests used in this study. The texas highway department presently makes use of the results of the sand equivalent and loss by decantation tests as. The elongation index is not applicable to sizes smaller than 6. Aggregates coarse aggregates 5 mm fine aggregates properties of aggregates must be known before mixing concrete to obtain a desirable mixture. Physical properties of fine and coarse aggregate uwmilwaukee. The aggregates used for making concrete are normally of the maximum size 80 mm, 40 mm, 20 mm, 10 mm, 4.
Recycled concrete as aggregate for structural concrete. The physical and chemical properties of cfa are given in tables 1 and 2, respectively. Elongation index the elongation index on an aggregate is the percentage by weight of particles whose greatest dimension length is greater than 1. Waste tyre crumb rubber particle as a partial replacement. The fine aggregate density depends on the inside solid material and void content, thus you need to measure the absorption rate prior to ensure how much water will be required in the concrete mixture. The gradation, particle shape and texture of the coarse aggregate along with fineness modulus of the fine aggregate will determine how low the fine to total aggregate percentage can be for a given workability requirement.
Physical properties of aggregates 19 fine aggregate angularity traffic depth from surface esals 100 mm. Aggregates are the most mined materials in the world. Aggregates for use in concrete 2 learning objective develop a basic understanding of aggregates and aggregate properties. The importance of using the right type and quality of aggregates cannot be overemphasized. Coarse aggregates those aggregates passing through 75 mm sieve and entirely retained on 4. Approximately 75% of the volume of concrete is occupied by aggregates, so quality of aggregates plays an important role in determining properties of concrete. Natural sand, crushed stone dust or manufactured sand by. Classification of aggregates based on size and shape. The compressive strength of aa concrete, however, sharply decreased when the replacement level of lightweight fine aggregates exceeded 30%. Correlation of concrete properties with tests for clay. Gravel aggregates are small rounded stones of different sizes which are generally obtained as such from some river beds. Aggregate grading grading of recycled coarse aggregate normally satisfies the standards for natural aggregate, while in the case of recycled fine aggregate. Mix proportions in order to investigate properties of cs concretes, six mixes were employed. The effect of shape, texture and grading of aggregates on fresh concrete was evaluated experimentally, quantified by means a proportioning method based on packing density concepts, the compressible packing model cpm, and analyzed by an empirical tool suggested by shilstone.
Properties of concrete with coconut shells as aggregate. Pdf study on properties of concrete using robosand as. This paper investigates the properties of some natural fine aggregates in. Each cfa was also tested for chemical properties which included determination of oxides, basic chemical elements, and mineralogy. In particular, the increase in the discontinuous grading of lightweight aggregate resulted in the deterioration of the mechanical properties. Properties of concrete with coconut shells as aggregate replacement 22 2. Fine aggregates generally consist of natural sand or crushed stone with most.
Physical properties the physical properties of aggregates are those that refer to the physical structure of the particles that make up the aggregate. Classification of aggregates based on shape and size such as coarse and fine aggregates are discussed here, aggregates are the important constituents of the concrete which give body to the concrete and also reduce shrinkage. Nine soil samples were obtained from different locations and. Basic properties of concrete with recycled concrete aggregate.
Textural properties give rise to internal characteristics, of which the pore size is perhaps most important. The coarse aggregate particles are usually crushed stone or crushed gravel, and the fine aggregate particles are usually natural sand. Properties of concrete with crumb rubber replacing fine aggregates sand article pdf available may 20 with 3,055 reads how we measure reads. Properties of aggregates construction aggregate porosity. In addition, table 2 shows the chemical composition of cement and wcbf, while. One source of fine aggregate was utilized in this investigation for the highstrength series h clsm mixtures. Properties of alkaliactivated mortar and concrete using. Aggregate particles have certain physical and chemical properties which make the aggregate acceptable or unacceptable for specific uses and conditions.