Concrete Mix
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2022 ◽  
Vol 5 (1) ◽  
pp. 77-82
Author(s):  
Yosi Haristha ◽  
Elfania Bastian

Concrete is the majority of materials used in construction in Indonesia in general. Concrete mix innovations are needed so that concrete has better quality and quality. Innovation in concrete mixture one of them by using organic waste. In addition to improving quality, organic waste used is expected to reduce global warming. In Nagari IV Koto Palembayan ijuk from enau trees is not processed and left alone, so over time the ijuk can become waste. In this study discussed the effect of the addition of ijuk in the concrete mixture against the strong press of concrete. The targeted concrete press strong value is 14.5 MPa. The test object is made by varying the amount of ijuk addition in the concrete mixture by 0.25% and 0.5%. The test object used is a cylinder measuring 15cm in diameter and 30 cm high. Testing was conducted when the concrete was 7 days old, 14 days and 28 days old using 2 samples of test objects. The results showed a strong value of normal concrete press age of 28 days obtained at 15.57, while the strong value of additional concrete press ijuk 0.25% and 0.5% obtained by 19.82 MPa and 18.26 MPa. The results showed additional concrete ijuk 0.25% increased by 27.30% from the normal concrete press strength and the strong value of additional concrete press ijuk 0.5% also increased by 17.28% from the strong normal concrete press.


2022 ◽  
Author(s):  
Sunita Kumari ◽  
Dhirendra Singhal ◽  
Rinku Walia ◽  
Ajay Rathee

Abstract The present project proposes to utilize rice husk and maize cob husk ash in the cement to mitigate the adverse impact of cement on environment and to enhance the disposal of waste in a sustainable manner. Ternary concrete / MR concrete was prepared by using rise husk and maize cob ash with cement. For the present project, five concrete mixes MR-0 (Control mix), MR-1 (Rice husk ash 10% and MR-2.5%), MR-2 (Rice husk ash 10% and MR-5%), MR-3 (Rice husk ash 10% and MR-2.5%), MR-4 (Rice husk ash 10% and MR-2.5%) were prepared. M35 concrete mix was designed as per IS 10262:2009 for low slump values 0-25mm. The purpose is to find the optimum replacement level of cement in M35 grade ternary concrete for I – Shaped paver blocks.In order to study the effects of these additions, micro-structural and structural properties test of concretes have been conducted. The crystalline properties of control mix and modified concrete are analyzed by Fourier Transform Infrared Spectroscope (FTIR), Scanning Electron Microscopy (SEM), and X-Ray Diffraction (XRD). The results indicated that 10% Rice husk ash and 5% maize cob ash replaced with cement produce a desirable quality of ternary concrete mix having good compressive strength. The results of SEM analysis indicated that the morphology of both concrete were different, showing porous structure at 7 days age and become unsymmetrical with the addition of ashes. After 28 day age, the control mix contained more quantity of ettringite and became denser than ternary concrete. XRD analysis revealed the presence of portlandite in large quantity in controlled mix concrete while MR concrete had the partially hydrated particle of alite.


2022 ◽  
Vol 1212 (1) ◽  
pp. 012032
Author(s):  
M A Dahim ◽  
M Abuaddous ◽  
H Al-Mattarneh ◽  
A E Alluqmani ◽  
R Ismail

Abstract Recycle and reuse of agriculture and industrial wastes becomes a big chalenge in different parts of the world. The success in the waste recycle could lead to conserve the environment, reduce the use of cement, and improve health environment. This paper presents the potential use of fly ash from olive oil waste in Jordan to improve concrete material which could be used as a sustainable material for rigid pavement and building construction material. Olive oil ash was collected from olive oil mill and replace cement in producing concrete material. The range of cement replacement was 0% to 12.5% with increment 2.5%. The results indicate that olive oil reduces the workability of concrete material. The reduction of the slump of concrete increases with increasing olive ash content. Strength and durability of concrete improved and increased with increasing olive ash content in concrete up to 7.5 percent then the strength reduced. The results in this study show that the use of 7.5% was the optimum replacement of cement. This percent could produce concrete with higher strength and higher durability in comparison with the control concrete mix. Olive waste ash enhances both strength and durability because it reduces the effective water-cement ratio in concrete mix and filling the pore and void structure in concrete material. The benefits of this study could reduce the cost of concrete and recycle waste material and enhance concrete properties.


2021 ◽  
Vol 14 (1) ◽  
pp. 437
Author(s):  
Wajeeha Mahmood ◽  
Asad-ur-Rehman Khan ◽  
Tehmina Ayub

This research aims to examine the effect of carbonation on the strength properties and carbonation depth of ordinary Portland cement (OPC) concrete using two different water to cement ratios (w/c) and two different replacement percentages of natural coarse aggregate (NCA) with recycled coarse aggregate (RCA). Two concrete mixes were prepared using w/c of 0.4 and 0.43. The two concrete mixes were subdivided into two subgroups based on the use of NCA and 30% RCA. The first concrete mix having w/c of 0.4 was contained NCA and from this concrete, 42 cylinders of 100 mm dia. and 200 mm height were cast. Six out of 42 cylinders served as control specimens and were not exposed to CO2. A total of 18 out of the remaining 36 cylinders was exposed to the simulated environment and the rest were exposed to the natural environment. The second concrete mix having a w/c of 0.4 contained 30% RCA/70% NCA, and using this concrete, 42 cylinders of similar size were cast. A similar scheme was adopted for w/c of 0.43 and, in total, 84 cylinders using four mix designs were cast. After casting and 28 days of curing, six out of 42 cylinders cast from each concrete mix design were tested for compression and splitting tensile strength, following ASTM C39 and ASTM C496 without any exposure to carbon dioxide (CO2). A total of 18 out of the remaining 36 cylinders was exposed to the simulated environment in a carbonation chamber for an equivalent time duration of 90, 180 and 365 days following CEN test guidelines and the other 18 cylinders were kept in the natural environment for a period of 90, 180 and 365 days. After the completion of simulated and natural exposure periods, these cylinders were distributed equally to test for compressive strength and splitting tensile strength to observe the effect of carbon dioxide (CO2) at each time duration (i.e., 90, 180 and 365 days), and replacement percentage of RCA (i.e., 0 and 30%), which showed that carbonation depth increases incrementally with the w/c ratio and CO2 exposure duration. In both the simulated and the natural environment, the use of RCA in concrete cast using a w/c of 0.4 increased carbonation depth up to 38% and 46%, whereas, in the case of the concrete cast using a w/c ratio of 0.43, the use of RCA increased the carbonation depth up to 16% and 25%. In general, the use of RCA in the concrete exposed to the natural environment significantly affected the compressive strength of concrete, due to multiple interfaces and the porous structure of RCA, and the variation in the temperature, humidity and content of carbon dioxide (CO2) present in the actual environment. The maximum compressive strength variation prepared from the mixes M0-0.4, M30-0.43, M0-0.43 and M30-0.43 differed by 5.88%, 7.69%, 16.67% and 20% for an exposure period up to 365 days. Similarly, the results of splitting tensile strength tests on cylinders prepared from the same mixes exposed to the natural environment differ by 7.4%, 27.6%, 25.41% and 18.2% up to 365 days of exposure, respectively, as compared to the simulated environment.


YMER Digital ◽  
2021 ◽  
Vol 20 (12) ◽  
pp. 694-709
Author(s):  
S Mahaboob Subhani ◽  
◽  
P Dinesh Sankar Reddy ◽  
S .Altaf Hussain ◽  
◽  
...  

Nature has blessed with natural resources like rocks / minerals, vegetation, air and water. These are about one crore eighty six lakhs living creatures existing in the world. Most of the living creatures are using their intellect and residing in the natures nest, where as human being is blessed with unique knowledge and wisdom which propelled to discover wheel, moving machineries and established good shelter with ultra architectural designs. Ancient man was living in huts further more constructed mud houses with the available clay / mud. Over a period of time man discovered calcium oxide to use in construction. In 1840s, a scientist by name William Aspdin has invented the manufacturing process of Portland cement production. Over a period of time, lot of advancements took place in producing different types of cement. During 1950’s fly ash was considered as a waste and used to land fill /dumps. Over a period of time man discovered compatible chemicals in fly ash and successful in mixing Ordinary Portland cement up to 30% which is called Pozzolana Portland cement. Several Researchers tried different waste materials to be used as a potential, concrete mix and have been successful in doing so. This paper deals in reviewing potential waste materials being used in cement concrete. Granite rocks are sliced to fine plates for the utility as flooring material. In the process of cutting and smothering the granite, fine dust of approximately 50µm is generated. Researchers discovered compatibility of granite saw dust in cement mix and were successful. Everyday hundreds and thousands of tones of plastic waste is generated. Researchers also tried to use plastic waste in civil construction and partially successful as plastic is organic in nature where as cement is inorganic in nature, nevertheless plastic waste is found as a potential mix in laying bitumen road. Limestone which consists of calcium atom and oxygen atom exists naturally in certain areas where as calcium oxide is also produced synthetically by cracking calcium carbonate at approximately 1000oC. Researchers have been successful in using calcium oxide, municipal waste in civil construction at different proportions. The optimal quality of final cement is governed by particle size and its distribution. Therefore adequate review is also done in terms of particle size, distribution and quality. The current objective of this review article is to give an insight about the sustainable technologies in cement using waste materials disposed in abundance.


2021 ◽  
Vol 5 (2) ◽  
pp. 74-84
Author(s):  
Syf. Umi Kalsum ◽  
Betti Ses Eka Polonia ◽  
Hurul 'Ain

Recycling is one way that is used to minimize the amount of waste that exists. Recycling is also a process to reduce the use of new raw materials, reduce energy use, reduce pollution, land degradation and greenhouse gas emissions. Materials that can be recycled consist of waste of glass, plastic, paper, metal, textiles and electronic goods. Glass has characteristics suitable as concrete aggregates, considering that glass is a material that does not absorb water. In addition, glass has high abrasion resistance. Meanwhile, the waste glass flux lowers the temperature to the temperature at which the formers will melt. Stabilizers in glass waste are made of calcium carbonate, which makes the glass waste solid and water-resistant. This glass waste is recycled by mixing it into the concrete mix. The recycling method is done by pounding the glass and putting it into the concrete mix stage. The purpose of mixing the glass waste is expected to increase the compressive strength of concrete. The use of glass waste as a mixed material affects the compressive strength of the concrete. The concrete with the most inferior to highest compressive strength is 4% variation concrete, 2% variation concrete, and traditional concrete. Optimal percentage addition of glass waste impacts on maximum concrete compressive strength is 2% mixture variation which obtained 11,88 Mpa & 11,32 Mpa.


Processes ◽  
2021 ◽  
Vol 9 (12) ◽  
pp. 2206
Author(s):  
Harry Hermawan ◽  
Peter Minne ◽  
Pedro Serna ◽  
Elke Gruyaert

Self-healing concrete has emerged as one of the prospective materials to be used in future constructions, substituting conventional concrete with the view of extending the service life of the structures. As a proof of concept, over the last several years, many studies have been executed on the effectiveness of the addition of self-healing agents on crack sealing and healing in mortar, while studies on the concrete level are still rather limited. In most cases, mix designs were not optimized regarding the properties of the fresh concrete mixture, properties of the hardened concrete and self-healing efficiency, meaning that the healing agent was just added on top of the normal mix (no adaptations of the concrete mix design for the introduction of healing agents). A comprehensive review has been conducted on the concrete mix design and the impact of healing agents (e.g., crystalline admixtures, bacteria, polymers and minerals, of which some are encapsulated in microcapsules or macrocapsules) on the properties of fresh and hardened concrete. Eventually, the remaining research gaps in knowledge are identified.


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