Types Of Waste Materials Research Articles

Waste-to-chemicals: Green solutions for bioeconomy markets

In the fast-developing time, the accumulation of waste materials is always in an uptrend due to population increases and industrialization. This excessive accumulation in waste materials harms the ecosystem and human beings by depleting water quality, air quality, and biodiversity. Further, by use of fossil fuel problem-related global warming, greenhouse gases are the major challenge in front of the world. Nowadays, scientists and researchers are more focused on recycling and utilizing different waste materials like a municipal solid waste (MSW), agro-industrial waste etc. The waste materials added to the environment are converted into valuable products or green chemicals using green chemistry principles. These fields are the production of energy, synthesis of biofertilizers and use in the textile industry to fulfil the need of the present world. Here we need more focus on the circular economy considering the value of products in the bioeconomic market. For this purpose, sustainable development of the circular bio-economy is the most promising alternative, which is possible by incorporating the latest techniques like microwave-based extraction, enzyme immobilization-based removal, bioreactor-based removal etc., for the valorization of food waste materials. Further, the conversion of organic waste into valuable products like biofertilizers and vermicomposting is also realised by using earthworms. The present review article focuses on the various types of waste materials (such as MSW, agricultural, industrial, household waste, etc.), waste management with current glitches and the expected solutions that have been discussed. Furthermore, we have highlighted their safe conversion into green chemicals and contribution to the bioeconomic market. The role of the circular economy is also discussed.

Cracking Behavior and Deflections in Recycled-Aggregate Beams Reinforced with Waste Fibers Subjected to Long-Term Constant Loading.

This report presents the results of long-term tests on concrete beams reinforced with steel cord. In this study, natural aggregate was wholly replaced with waste sand or with wastes from the production of ceramic products and ceramic hollow bricks. The amounts of individual fractions used were determined in accordance with guidelines for reference concrete. A total of eight mixtures were tested; these differed in terms of the type of waste aggregate used. Elements with various fiber-reinforcement ratios were made for each mixture. Steel fibers and waste fibers were used in amounts of 0.0%, 0.5%, and 1.0%. Compressive strength and modulus of elasticity were determined experimentally for each mixture. The main test was a four-point beam bending test. Beams with dimensions of 100 mm × 200 mm × 2900 mm were tested on a stand, which was specially prepared so that three beams could be tested simultaneously. Fiber-reinforcement ratios were 0.5% and 1.0%. Long-term studies were conducted for 1000 days. During the testing period, beam deflections and cracks were measured. The obtained results were compared with values calculated using several methods, considering the influence of dispersed reinforcement. The results enabled the best methods for calculating individual values for mixtures with different types of waste materials to be determined.

The Socio-Economic and Environmental Benefits of Waste Scavenging in Maiduguri, Borno State

This study aimed at assessing the economic and environmental benefits of waste scavenging in Maiduguri, which has been presumably neglected by formal sector. The objectives of the study were to: identify the types of waste materials recovered by scavengers, determine the average monthly income and factors that influence the income of Scavengers and examine the environmental benefits of waste scavenging. Data were collected using Questionnaire and observation checklists. Five wards out of the 15 wards that constituted the study area were purposively selected for the study. 210 scavengers were randomly selected and administer Questionnaire at the depots in each of the sampled wards where they sell recovered materials. The data collected were analyzed using descriptive statistics and chi square test. The study found that scavenging is a male dominated occupation, with a mean age of 20.2 and average monthly income of N13, 500. The Chi-square test performed to demonstrate the influence of socio demographic factors on income of scavengers revealed a significant association between Age, Educational attainment, length of practice, marital status and categories of waste scavengers. Gender and alternative occupation were the only insignificant factors. The study also showed that, Scrap metals and aluminum were the major materials recovered by scavengers as ascertain by 65.71%, and that the materials are recovered base on their economic value, quality and state. Seasonal differences also contribute to the pricing of recyclable materials recovered by scavengers. The study also revealed that despite the significant contribution of scavengers to environmental sustenance, economic growth and poverty reduction, their activities is still not acknowledge by local authorities in the study area. The study recommends that Government should recognize their contributions as important stakeholders in the waste management sector in Maiduguri by diversifying the types of recyclables and establishing recycling plants, more permanent employment could be provided for the scavengers and other people, thereby improving the economy. Also, Successful integration of scavengers into a formal programme can help optimize waste collection and recycling in an integrated waste management programme. If well organized, scavengers could be given the necessary training that would enable them overcome the challenges they encounter in their activities, especially those related to vulnerability of hazards.

AUTOMATIC BEACH CLEANING ROBOT

“It is a massive problem that affects everybody around the world,” said Alex Schulze, co-founder of 4ocean, a marine clean up company that removes a pound of trash from the beach for every product they sell, which includes apparel and accessories, so we are trying to solve this problem through our "Automatic ROBOT" which helps us to clean our beach and provide us healthy nature and also used for clean marine life, aquatic animals because they also deserve a better life. This robot is portable through this “AUTOMATIC ROBOT” there is no need for manpower use in beach cleaning. The Automatic ROBOT developed by 4ocean is a significant step towards addressing the issue of ocean pollution, as it offers several advantages over traditional manual beach cleaning methods. In addition to being portable, the robot is equipped with advanced sensors and technology that enable it to identify and collect different types of waste, including microplastics and other small debris that can be difficult to spot with the naked eye. This not only helps to ensure a more thorough and effective cleaning process but also minimizes the risk of human error and injury, as well as reducing the time and cost required for beach cleaning. Furthermore, by keeping our beaches and oceans clean, we can protect and preserve the natural habitats of marine life and aquatic animals, which are essential to the health and well-being of our planet. The purpose of this paper is to present the development of a cutting-edge beach cleaning robot that utilizes advanced components, including an Arduino Uno board, flame sensor, GSM, wiper motor, DC clamp motor, cycle chain sprocket, 60rpm DC gear motor, L298 DC motor driver, Pedestal bearing UCP 204(20MM ID), and solar panel. Through the integration of these innovative technologies, the beach cleaning robot can function autonomously and effectively identify and remove various types of waste materials, such as plastics and metals, from the beach environment. This project is an essential step towards improving environmental sustainability and promoting eco-friendly practices in beach cleaning operations. Keywords – Automatic Beach Cleaning Robot (ABCR), Internet of Things (IoT), Arduino Uno (AU).

Investigation of the Electrochemical Performance of Titanium-Based MXene Hybridisation with Rice Husk Ash (RHA) as an Anode Catalyst Support Material

MXenes possess unique features that are useful for broader industrial development. However, although many different compositions of MXenes have been discovered, little research has been conducted on the optimal synthesis strategy for producing the best MXenes yield. Therefore, substantial work is performed on the synthesis’ structure and property relationship for direct methanol fuel cell (DMFC) applications since MXenes have been successfully hybridised with rice husk ash (RHA). In this study, to produce titanium-based MXene, Ti3C2 nanopowders are added to the rice husk ash matrix to synthesise hybrid RHA/MXene composites (R-MX). Using different weight percentages of MXene hybridised with rice husk ash (2 wt. % R-MX, 4 wt. % R-MX and 6 wt. % R-MX), different electrochemical properties are obtained. Meanwhile, electrochemical analysis is undertaken to investigate the methanol oxidation performance using Linear Sweep Voltammetry (LSV). The highest percentage of the R-MX hybrid composite, 6 wt. % MXene, showed the lowest Tafel slope (148 mV/dec) and the highest ionic exchange current density in the same Tafel analysis. Moreover, the incorporation of MXene into RHA produced good results from the chronoamperometry analysis (CA), with the highest percentage of the hybrid composite, R-6MX, showing the highest retention rate of 97.28%. Meanwhile, the Nyquist plot analysis showed an increasing semicircle arc diameter at the lower-frequency region, implying a lower interfacial charge resistance upon the addition of MXene into RHA. This outcome corresponded to the CA and LSV analysis findings, R-6MX showed a remarkable performance in terms of having the highest peak current density of 0.9454 mA/cm2 and retention rate of 97.28%. Both of these values show that hybrid R-6MX was able to maintain a high current for the entire duration. The current is maintained in a stable form for some time, proving that R-6MX was the most stable, with a minimal corrosion reaction and tolerance in a methanol medium. The results from this study enabled an evaluation of the possibility of utilising low-cost, green RHA material for fuel cell applications to promote sustainability. The novelty of this work is that a cheap source of silica-based RHA, a type of waste material, is incorporated with MXene through hybridisation processes.

WASTE CLASSIFICATION USING RESNET-152

Waste classification is the process of identifying and separating different types of waste materials based on their characteristics, such as composition, size, and shape. Accurate waste classification is important for efficient waste management and resource recovery, as it allows for the proper disposal or reuse of waste materials. One method for automated waste classification is the use of deep learning algorithms, such as the ResNet-152 model. ResNet-152 is a convolutional neural network (CNN) that has been trained on a large dataset of images and is able to classify objects in images with high accuracy. By applying ResNet-152 to images of waste materials, it is possible to classify the materials into different categories, such as paper, plastic, or metal. This can be done in real-time using computer vision techniques and can significantly improve the efficiency and accuracy of waste classification processes. However, the success of waste classification using ResNet-152 or other CNNs depends on the quality and diversity of the training data, as well as the availability of computational resources and infrastructure. Key Words: Computer Vision, Deep Learning, Transfer Learning, ResNet-152, Waste Management.

Utilization potential of borogypsum and silica fume in producing lightweight building material

The present study is aimed at investigating the utilization of two crucial industrial wastes, borogypsum and silica fume, as the main raw materials in the production of building materials. For this aim, different receipts were designed from boron waste (borogypsum) belonging to Emet Boric Acid factory (Kütahya/Turkey) and silica fume, which was taken from Electrometallurgy facilities (Antalya/Turkey). Mixtures were prepared so that the amount of waste material used in the composition was 90%, and the remaining 10% was binder clay. The samples were prepared with different proportions of both wastes were pressed uniaxially at 10 MPa, and the shaped samples were then fired at 1000, 1050, 1100, and 1150 °C. Physical and mechanical tests, as well as mineralogical and microstructural analyses, were carried out on the fired samples. The technical properties of the samples derived from the wastes were evaluated depending on the type of waste material and its usage amounts, and firing temperatures. It has been understood that the use of high Borogypsum will cause high firing loss, which will negatively affect the dimensional stability of the material. Moreover, with silica fume addition to borogypsum, the water absorption and porosity values increased, and the strength values decreased accordingly. Consequently, the water absorption and bending strength values obtained in the samples prepared from a mixture of 70% borogypsum and 20% silica fume can be considered the usage as a wall tile is possible since they coincide with the technical properties defined in the EN ISO 10545-3 and EN ISO 10545-4 standards, respectively.

Mechanical Properties and Flexural Strength of Reinforced Concrete Beams Containing Waste Material as Partial Replacement for Coarse Aggregates

The volume of waste materials and by products are increasing and endangering the environment safety. Some of these waste materials can be used in the production of building materials, such as concrete. In order to study the possibility of using some waste materials as aggregate replacement for the purpose of producing structural RC members this investigation was carried out. This research describes the results of test of reinforced concrete beams containing different types of waste materials, namely crumbed rubber, granular plastic, and crushed bricks. Ten RC beams containing different percentages (0%, 5%, 10%, and 15%) of waste materials as coarse aggregate replacement have been investigated. The beams were 150 × 200 mm in size and 2000 mm in length and tested under four points loading. Mechanical properties of the concrete used for the beams were also studied. Test results indicated a reduction in compressive strength, splitting tensile strength, and elastic modulus due to the inclusion of the waste materials used. The maximum loss in concrete compressive strength was recorded to be 54.95%, 50.31%, and 20.41% for concrete mix with 15% crumbed rubber, plastic waste aggregate, and 5% crushed brick, respectively. Test results of the beams showed that ultimate load capacity was reduced by 30.21% and 9.94% when 15% of crumbed rubber and granular plastic were used, respectively. The failure mode of all the tested beams was similar and followed same pattern, steel yielding followed by concrete compression failure. Finally, based on the flexural capacity of the beams tested it is recommend that gravel replacement of up to 15% of crumbed rubber, granular plastic, and crushed brick can be safely used to produce normal type of RC beams for minor structural application.

CHARACTERISTIC STUDY OF INDUSTRIAL SLUDGE, TREATMENT AND THEIR DISPOSAL MECHANISM

This research papers is the characteristic study and suggestive measure for disposal mechanism for the sludge. Sludge is one of the important common waste materials which is generated in tons per day from many industries. The different types of waste materials can undergo various treatment based upon its characteristics which also resulted in the variation for the treatment like Stabilization before disposal, Direct Landfill (DLF), Alternative Fuel and Raw material (AFRF), Incineration, Solvent recovery, Chemical treatment, Recycling of metals and others for the Hazardous waste management process. The various physicochemical, gravimetric and spot test were carried out in order to determine the quality of the waste and its suitability for the disposal by following different national and international methods. Further, Heavy metals were also analyzed by AAS obtained by following different methods in different forms like TM, TCLP and WLT which also indicated that the heavy metals are within the limits. Overall, the results obtained were found to be within the limits provided by the CPCB guidelines and the waste is suitable for the direct landfill disposal mechanism. KEYWORDS: Industrial Sludge, Hazardous Waste Management, Heavy metals

Multicomponent Low Initial Molar Ratio of SiO2/Al2O3 Geopolymer Mortars: Pilot Research.

Alkali-activated binders have the potential to consume various types of waste materials. Low initial molar ratios of SiO2/Al2O3 geopolymer mortars were considered in this article. Here we studied alkali-activated binders produced with photovoltaic glass powder in 5%; kaolin clay in 15%; ground granulated blast furnace slag in 30%; alumina-lime cement in 30%; and, interchangeably, fly ash from coal combustion in 5%, fly ash from biomass combustion in 5%, or granulated autoclaved cellular concrete in 5%. The influence of clay dehydroxylation, curing conditions, glass presence, and a kind of waste material was investigated. According to the experimental results, strength (compressive and tensile) gradually increased with increasing time and with the use of calcined clay. Significant improvement in compressive strength was seen with the additional 3 days curing time in 105 °C when non-sintered clay was used. The presence of photovoltaic glass in alkali-activated mortars immobilised mercury and arsenic but released zinc, chromium, and sulphates. The microscopic observations confirmed the greater densification of the microstructure of the binder made of calcined clay due to its greater surface development and dehydroxylation. The binder of non-calcined clay was granular, and the interfacial transitional zone was more porous. The C–A–S–H gel seemed to be the main phase. XRD examination confirmed the presence of C–A–S–H, C–S–H, zeolites, and many other phases in minor amount. The presented research was a pilot study, and its main goal was to develop it further.

Recycling light-emitting-diode waste quartz sand and stone sludge for the synthesis of amine grafted mesoporous humidity control material

This article proposes a cost-effective development method to recycle two types of waste material (i.e., light-emitting-diode (LED) waste quartz and stone sludge) to produce mesoporous materials. The proposed method is simple yet effective. Extraction of the precursor liquid from the silicon and aluminum sources respectively contained in the waste quartz and stone sludge is based on the alkali fusion method, and the mesoporous material is synthesized after the hydrothermal reaction. The novelty of this work lies in our functionalization of Mobil Composition of Matter No. 41 (MCM-41) through amine group grafting (AGG-MCM-41). The results show that the structure of the mesoporous MCM-41 grafted by the amine functional groups remains orderly. The 29Si nuclear magnetic resonance spectrum confirmed that the supported surface of the MCM-41 features a large number of silanol groups, which verifies that modification of the amine functional group improved the effect. The results show that when the addition amount of amine functional group is 5 vol% (when relative humidity = 95%), the highest equilibrium moisture content of the material is 26.5 kg/kg. The wet performance of the material was studied, and it was proved that 5.0-AGG-MCM-41 complies with the standard of Japanese Industrial Standard (JIS A 1475) (equilibrium moisture content>5 m3/m3). The research results also show that the optimal equilibrium moisture content is more than 44 times that of metal-organic frameworks humidity pump. Therefore, the synthesized AGG-MCM-41 offers excellent humidity control performance in the practical application of building materials as it narrows the indoor humidity fluctuation spontaneously without any energy consumption. This creates new opportunities for smart indoor humidity control. The amine-group-grafted MCM-41 effectively reduces the shortcomings of high energy consumption, high costs, and insufficient space caused by mechanical dehumidifiers. In addition, the production of AGG-MCM-41 from LED waste and stone sludge achieves 100% recycling. Transformation of two problematic industrial byproducts into humidity-conditioning materials with beneficial technical and environmental properties represents a significant contribution towards the goals of sustainable development.

Utilization of Waste Clay Bricks and Waste Lightweight Concrete Blocks as Fine Aggregates for the Preparation of Mortar

Recently there has been major attention towards waste materials for converting them into useful materials. This study is aimed to investigate the possibility of utilizing waste clay bricks and waste lightweight concrete blocks as suitable materials for partial replacing of the fine aggregate in the production of cement mortar. In mortar mixes, waste clay bricks constitute 10%, 20%, 30%, and 40% of fine aggregate. On the other hand, the second line (waste lightweight concrete blocks) has contained 10%, 20%, and 30% of the natural sand produced. Some mixes have contained the combination of two types of waste materials together (20% clay bricks with 10% lightweight concrete block, 10% clay bricks with 20% lightweight concrete block, and 15% clay bricks with 15% lightweight concrete block respectively). The effects of the wastes aggregate on flow and engineering properties (i.e., density, compressive strength, flexural strength, and water absorption) of mortar have been also investigated at 7, 28, and 360 days. The results have presented a reduction in the flow of mortar when using a waste aggregate and a significant increase in compressive and flexural strength when using waste clay bricks aggregate at different percent. Utilizing lightweight concrete blocks aggregate has a clear effect on mortar density.

Waste Material via Geopolymerization for Heavy-Duty Application: A Review.

Due to the extraordinary properties for heavy-duty applications, there has been a great deal of interest in the utilization of waste material via geopolymerization technology. There are various advantages offered by this geopolymer-based material, such as excellent stability, exceptional impermeability, self-refluxing ability, resistant thermal energy from explosive detonation, and excellent mechanical performance. An overview of the work with the details of key factors affecting the heavy-duty performance of geopolymer-based material such as type of binder, alkali agent dosage, mixing design, and curing condition are reviewed in this paper. Interestingly, the review exhibited that different types of waste material containing a large number of chemical elements had an impact on mechanical performance in military, civil engineering, and road application. Finally, this work suggests some future research directions for the the remarkable of waste material through geopolymerization to be employed in heavy-duty application.

Geosynthetic Encased Concrete Debris Stone Columns

Rapid urbanization has compelled the building industry to improve the soft soil grounds which otherwise are unsuitable for construction activities. Ground improvement helps achieve better performance by avoiding several problems like excessive settlements, large lateral flow of soft soil beneath the structures, and loss of global or local stability under operational loading conditions by modification of foundation soils. The growing quantities and types of waste materials, shortage of landfill spaces, and lack of natural earth materials highlight the urgency of finding innovative ways of recycling and reusing waste material additionally can reduce the demand for natural resources creating sustainable ecosystem. The aim of this experiment is to use crushed concrete debris (CCD) in soil stabilization. A series of experiments are to be carried out to develop an understanding on the performance of soft clay foundation beds reinforced using geosynthetic encased stone-concrete debris column. Model tests was conducted on clay reinforced with encased vertical columns filled with both CCD and aggregates. A comparative study is to be done and an assessment of ultimate bearing capacity of the composite ground is to be done. The column failure mechanism in the both the cases are to be carefully studied. Modal tests and later numerical analysis is done in PLAXIS 2D for analyzing the behavior of geosynthetic encased stone column stabilized clay bed numerically. Analyses were carried out using Mohr-Coulomb’s criterion. Lab conditions were simulated in PLAXIS for accurate comparison for same model tests.

Stabilization of Lead-Contaminated Mine Soil Using Natural Waste Materials

Stabilization was applied as a remediation option for immobilizing lead (Pb) in contaminated mine soil. Four types of waste materials were used as stabilizing agents, namely waste oyster shells (WOS), calcined oyster shells (COS), natural starfish (NSF), and spent-coffee-grounds-derived biochar (SCGB). The Pb-contaminated mine soil was treated with the stabilizing agents ranging from 0 to 10 wt% and a curing period of 28 days. The toxicity characteristic leaching procedure (TCLP) was employed for evaluating the effectiveness of the remedial process. The Pb immobilization mechanism in the treated mine soil was investigated using scanning electron microscopy–energy dispersive X-ray spectroscopy (SEM-EDX) analyses. The obtained results showed that the TCLP Pb levels decreased as the stabilizing agent dosage increased. The WOS and COS stabilizing agents immobilized Pb effectively in the contaminated mine soil. Application dosages of 4 wt% and 2 wt% for WOS and COS, respectively, were sufficient for compliance with the TCLP regulatory level of 5 mg/L. For the NSF and SCGB treatments, 4 wt% and 10 wt%, respectively, were necessary to meet the TCLP regulatory limit. The effectiveness of Pb immobilization was found to increase in the following order: SCGB < NSF < WOS < COS. The chemical fraction analyses showed that the lower F2 (weak acid soluble) fraction and higher F3 (reducible) and F4 (oxidizable) fractions were most likely associated with the high level of Pb immobilization. Moreover, the SEM-EDX analysis results showed that the most effective Pb immobilization could be strongly associated with the pozzolanic reaction products.

Industrial Internet of things-based solar photo voltaic cell waste management in next generation industries.

Nowadays, modern industries generate their energy by using renewable solar. The rapid increase in photovoltaic (PV) module installations provides a better energy conversion, but their life cycle is a major concern. This research paper focuses on the recycling process for solar PV modules using the Internet of Things in industries. The smart bin with the Internet of Things (IoT) utilizes a machine learning approach to collect solar waste. The proposed smart bin uses k-Nearest Neighbor's algorithm (k-NN) and Long Short-Term Memory (LSTM), a network-based learning algorithm. These algorithms are useful in updating the level of the bin via alert messages. It also helps in identifying the type of waste material. The k-NN algorithm provides 83% accuracy in predicting the bin level in a real-time testing environment. The smart dust bin classifies the waste materials, and notifies its level to the collection center through the IoT platform when the level reaches a prescribed threshold, the signal corresponding to the level is passed to the common waste collection unit. IoT is connected to Cloud Server. It helps to predict the level of the smart bin. Delay is introduced in the order of 3-8s while the alert message is sent to the common waste collection unit. The system monitors the smart bin levels and sends the notifications to alert and initiate the collection unit. Real-time mobile app monitors the bin's level and location. The cloud IoT analytics analyze the solar e-waste in a different locations in industries.The proposed system works better and provides accurate results by using machine learning approach.

Use of Municipal Solid Waste Incineration Bottom Ash and Rice Husk Ash as Blended Cement

The issue related to disposing the waste material from the industries becomes one of a major problem to the environmental, economic, and social issue. However, natural resources consume worldwide, while at the same time increased amount and type of waste material has resulted in a waste disposal crisis with a growing consumer population. In this project, Municipal Solid Waste Incineration (MSWI) by-product which is bottom ash and rice husk ash were used as blended cement. This research paper is prepared to investigate the utilization of municipal solid waste incineration bottom ash in blended cement and designed for the strength of 15 MPa at 28 days will be evaluated for its early-stage properties. Rice husk ash is used to reduce the amount of cement in mortar and it helps to increase the durability of mortar while keeping up consistent workability. The percentage of replacement in cement is by 0% (control), (5% rice husk ash + 10% bottom ash), (10% rice husk ash + 10% bottom ash), and (15% rice husk ash + 10% bottom ash) The result of this research indicates that 5% of replacement of rice husk ash with 10% of bottom ash shows highest compressive strength with 17.79 MPa with density 2080 kg/mɜ and water absorption of 5.18% at 28 days. This study proved that the addition of bottom ash can increase the durability, workability, and strength of mortar containing rice husk ash as a replacement for cement.

Enhancement of Agro-Industrial Waste Composting Process via the Microbial Inoculation: A Brief Review

Composting is an important technology used to treat and convert organic waste into value-added products. Recently, several studies have been done to investigate the effects of microbial supplementation on the composting of agro-industrial waste. According to these studies, microbial inoculation is considered to be one of the suitable methods for enhancing the biotransformation of organic materials during the composting process. This review provides up-to-date research findings on microbial inoculation strategies and their role and functions in enhancing the composting process and the improvement of compost quality. Based on this review, the addition of microorganisms could enhance the composting process such as accelerating the organic matter degradation, mineralization and microbial enzymes activities, and the quality of the end-products such as high germination index. It is important to notice in this strategy that sludge’s microbial consortium is feasible to enhance the composting process in pilot-scale and industrial-scale productions. Besides, it also reduces the cost of compost production. The findings of this review show the various positive impact of microbial inoculation on agro-industrial waste composting which in turn might be useful as a reference for selecting a suitable inoculum based on the type of waste materials.

The effect of nanosilica incorporation on the mechanical properties of concrete exposed to elevated temperature: a review.

Exposing concrete to high temperatures leads to harmful effects in its mechanical and microstructural properties, and ultimately to total failure. In this sense, various types of waste materials are exploited not only to tackle serious environmental issues but also to enhance the thermal stability of concrete exposed to elevated temperatures. Furthermore, nanomaterials have been incorporated in concrete as admixtures to reduce the thermal degradation of concrete due to exposure to high temperatures. In the present study, the effects of nanosilica (NS) incorporation on the properties of concrete subjected to elevated temperature are discussed in several sequential sections. The process mechanism of concrete deterioration due to fire exposure and the important factors that could affect the performance of concrete under fire were evaluated. Moreover, brief highlights on the effect of elevated temperature on concrete containing waste materials are included in this review paper. Reviews and summaries of the available and updated literature regarding concrete containing NS are considered. According to the findings of the studies under review, the addition of nanosilica to concrete contributed in reduced strength loss, minimized internal porosity, and enhanced matrix compactness in concrete.

Mechanical properties of recycled aggregates concrete with sisal fiber and silica fume

Concrete is a heavily reliant material in the field of construction with aggregates the key ingredient. In construction, various practices like renovation, updating of new rules in construction, obsolescence and demolition leads to the accumulation of large quantity of wastes. Mainly it contains large amount of concrete contents which are considered as solid waste. It necessitates the importance of research for the management of these solid wastes, particularly construction and demolition (C&D) wastes. By converting them for the new construction purposes we can effectively use these type of waste materials. The government would incur colossal losses and the ecosystem will suffer greatly degrading the sustainability of concrete. Hence in this research, the objective was chosen to recycle the old Concrete waste as coarse aggregate with different grades to prepare new mixes in M30 mix design. We can solve the impact of these wastes by strengthening and reutilizing the demolished wastes by adding sisal fibres with silica fumes as admixtures to the recycled aggregate concrete to improve the mechanical properties of the RAC. The effective usage of the demolished Construction waste can reduce the environmental consequences to a great extent as well as the transformation of waste materials into aggregates helps to overcome the problem of material scarcity in the field of construction. As we know, in case of rigidity and strength the name concreate comes as ultimate, so that reusing the used concrete aggregate helps in various fields under cost effectively.