The unit price of the prepared CRFA concrete was around 12.7% lower than that of the natural aggregate concrete. Additionally, the proposed procedure for the concrete mixture design could recycle all concrete waste into the new concrete and replace all the natural fine aggregate in the concrete mixture.
This paper is devoted to the studies of material and mechanical properties of recycled aggregate concrete using packing density method. This paper
Mix Design and Properties of Recycled Aggregate Concretes Applicability of Eurocode 2 International Journal of Concrete Structures and Materials, 2014 George Wardeh
Jun 29, 2017 Malesev M, Radonjanin V, Marinkovic S (2010) Recycled concrete as aggregate for structural concrete production. Sustainability 2(5)12041225. Article Google Scholar 44. Ajdukiewicz AB, Kliszczewicz AT (2007) Comparative tests of beams and columns made of recycled aggregate concrete and natural aggregate concrete.
Nov 27, 2012 In the process of mix design of pervious concrete with either natural aggregate or recycled concrete aggregate, Fig. 11 could be used to obtain the void content needed for trial mixes to satisfy the specification requirement for water permeability and compressive strength of concrete. Once the void content is known, simple mathematical approach ...
Rasiahsriravindra rajah et. al. (2012) 4 prepared a mix design for pervious concrete which is made of recycled aggregate and to replace the cement 70% of its weight with Ground Granulated Blast ...
May 02, 2020 Abstract This study proposes a new mix design method for C30 recycled concrete using recycled aggregate crushed from different strength source concrete (SC). The dosages of cement, water, sand, and coarse recycled concrete aggregate (CRCA) are the same as the corresponding components in natural concrete, but the CRCA should be pre-wetted
For the environment protection and sustainable development in building construction, waste concrete can be processed into recycled aggregate to mix the recycled aggregate concrete (RAC). However, the existing mix design methods of RAC were complex, and the mechanical properties of RAC were more weakened than ordinary concrete. This paper presents a simple
Mar 02, 2018 Aggregate shapes effect on concrete quality. By Frank Bowen. Editors Note This is the second article in a year-long series that explores the science of concrete to provide a better understanding of mix design. The series will be collaboratively written by Paul Ramsburg, technical sales specialist at Sika Corp., and Frank Bowen, quality control manager at
Aug 25, 2008 Much of the U.S. research focused on using crushed, hardened concrete as an aggregate in fresh concrete has been in mainline paving. Work on this topic began with a major effort in the 1980s in Minnesota. Unfortunately, most of the research focused on using recycled concrete aggregate (RCA) as a base material to the pavement.
Mar 03, 2020 In this method of mix design, the acceptable percentage of recycled concrete aggregate (RCA) depends on the AMC value. Five different batches of design mixes were prepared, including one batch that used conventional design from natural aggregate, two batches that used conventional design from RCA, and two batches that used the proposed
Mar 08, 2016 The final mix design proportions for the recycled hot mix paving mixture will be determined by completing mix design testing using standard procedures to satisfy applicable mix design criteria. Additional virgin aggregates may be required to satisfy gradation requirements to improve stability and to limit the RAP content in recycled hot mixes.
The use of concrete with recycled aggregate in reinforced concrete structures is allowed by several design standards 9 and, as a result, some studies 10, 11 and practical applications 12 have reported the inherent gains in economic or sustainability terms of this material.
Aug 02, 2018 In this work, Recycled Coarse Aggregate (RCA) is replaced 100% to produce RAC. The Particle Packing Method (PPM) is proposed for the mix proportioning of concrete. In PPM, the smaller particles are selected to fill up the voids between large particles and so on.
Aug 26, 2014 At fresh state, the mix design of concrete with recycled aggregates requires an additional quantity of water to obtain a similar workability as a concrete formulated with natural aggregates (Hansen and Boegh 1986 ). Such a modification may obviously affect the mechanical characteristics of recycled aggregates concrete.
Oct 30, 2020 RSM can be used to design the mix proportion of recycled aggregate pervious concrete. Experiments on the paste based on BBD show that IPT and ACT are significantly affected by the dose combination of three admixtures (SP, VMA, and RE). The most significant factor affecting IPT is VMA 2, while the linear term SP has strongest influence on ACT.
By using packing density mix design method, recycled aggregated concrete strengths fluctuation can be resolved, and the concretes can have similar strengths consistency, regardless the recycled ...
among porosity, compressive strength and water perme- At 50 % cement replacement with y ash, the compressive ability, needed for the mix design of pervious concrete mixes strength of pervious concrete was reduced by 44 % but the with either natural aggregate or recycled concrete aggregate. permeability was marginally improved, when compared with the
This paper demonstrates that RSM can be used to design the mix proportion of recycled aggregate pervious concrete. From the perspective of the internal structure of recycled permeable concrete, the factors affecting its strength and porosity are the paste properties, the coating thickness of paste on the surface of aggregate and the void content of aggregate.
Keywords pervious concrete, porosity, strength, permeability, recycled concrete aggregate, mix design. 1. Introduction In recent times, major cities around the world have experienced frequent ooding due to the combination of increased rainfall and reduced in
This paper considers mix of two different aggregate sizes of 10 and 20mm, 0, 30, 50, 70 and 100% recycled aggregate replacement ratios, and water-cement ratio of 0.35, 0.45 and 0.55. In total of fifteen concrete mix designs are considered. The paper presents the material properties of aggregates which were obtained from the material testing.
mix design procedure for recycled aggregate concrete Conservation of natural resources and preservation of environment is the essence of any development. Use of recycled aggregate concrete (RAC) is one such attempt and is an answer
The undesirable properties of conventional recycled fine aggregate (RFA) often limit its application in the construction industry. To overcome this challenge, a method for preparing completely recycled fine aggregate (CRFA), which crushes all concrete waste only into fine aggregate, was proposed. The obtained CRFA had high apparent density, and its water
Apr 26, 2012 The results showed that the use of 100% recycled concrete aggregates increased the optimum moisture content and decreased the maximum dry density of base course materials compared to those of natural base materials. The effect of recycled aggregate replacement on un-confined compressive strength was discussed at 7, 28 and 90 days.
This study proposes a new mix design method for C30 recycled concrete using recycled aggregate crushed from different strength source concrete (SC).
Aug 14, 2017 Using recycled pavement as aggregate in new concrete mixes can save money and promote environmental sustainability. New design methods published in a new research report allow engineers to create more durable mixes from recycled aggregate than in the past, reducing the need for virgin aggregate, a diminishing and expensive resource.
In this project, the mix design of M30 grade of cement concrete is developed at water cement ratio 0.45 using virgin coarse aggregate (CA). In order to study the potential of RAP in the mix design of M30 grade cement concrete, different percentage of RAP aggregate are
concrete mix design. Mills-Beale J. and You Z. (2010) investigated the viability of using recycled concrete aggregate for a typical light duty asphalt highway and concluded that the use of recycled concrete aggregate would save some amount of compaction energy. Arabani M. and Azarhoosh A. R. (2012) concluded that
Apr 21, 2020 The mix design process also lends us a mix ratio that defines the parts of sand and crushed stones to be added for 1 part of cement. It is generally expressed as Mix Ratio Cement Fine Aggregates Coarse Aggregates. For example, a mix design ratio of 124 indicates that for 1 part of cement, we have 2 parts of sand and 4 parts of crushed ...
Aug 19, 2020 Methodology. Recycled concrete aggregates are generally more porous than the primary coarse aggregates. The main property of pervious concrete is its permeability, so the part of fine aggregate can be reduced and the part of natural aggregate can be replaced with recycled concrete aggregate to enhance permeability without much affecting the strength of
To give it good load bearing partial replacement of natural aggregate with 0%, capability when under tension, it has to be 25%, 50%, 75%, 100% recycled aggregate and reinforced with steel bars, polymer strands or fibers cement with 25% of fly ash, 1% of PET to the total .It is the most commonly used building weight of concrete and the mix ...
Mix Design and Properties of Recycled Aggregate Concretes Applicability of Eurocode 2. George Wardeh*, Elhem Ghorbel, and Hector Gomart. (Received May 23, 2014, Accepted July 24, 2014) Abstract ...
In addition, concrete made with 20% of mixed recycled aggregate presented a reduction of only 0.6% in maximum compressive strength and 36.8%
Feb 28, 2019 However, using a recycled aggregate of more than 65% can impact the mixs durability significantly, reducing its physical properties tenfold. The optimum amount blended in with the concrete should be 35%. Some experiments have shown that the recycled aggregate is durable, no doubt, but not as sturdy as natural coarse aggregate.
Recycled concrete, or crushed waste concrete, is a feasible source of aggregates and an economic reality, especially where good aggregates are scarce. Conven-tional stone crushing equipment can be used, and new equipment has been developed to reduce noise and dust. Aggregates must conform to certain standards for