Plastic Aggregates Research Articles

Investigation of the physical-mechanical properties and durability of high-strength concrete with recycled PET as a partial replacement for fine aggregates

In this study, PET plastic waste, which is a type of polymer commonly used in the manufacture of plastic bottles, has been incorporated into concrete by partially replacing the natural fine aggregate. An experimental study was conducted by casting and testing 90 concrete cylinders and 54 concrete cubes. A concrete mixture was designed in which the natural fine aggregate was substituted partially with PET plastic waste (PW) at a ratio of 0%, 25%, and 50%, with various w/c ratios of .40, .45, and .55. Physical, mechanical, and durability properties were assessed. The downside of the test results show degradation in each of the following characteristics: slump, compressive strength, splitting tensile strength, ultrasonic pulse velocity, water absorption, and porosity. The degradation of these characteristics increased with the increase in the volume of plastic aggregate (PA) and the w/c ratio. While the positive side of the results showed that with the increase of the PA volume and the w/c ratio, the fresh and dry densities decreased further, and by using 50% PET, the dry density became below 2000 kg/m3. Therefore, it is classified as lightweight concrete. Moreover, the fracture of concrete changed from brittle to more ductile compared to control concrete. Also, the thermal conductivity decreased significantly (11%–47%), and by using 50% of PET, the thermal conductivity became less than .71 W/mK, and accordingly, classified as a bearing insulator.

High-strain rate compressive behavior of concrete with two different substituted recycled plastic aggregates: Experimental characterization and probabilistic modeling

This paper presents a pilot study on the characterization of the high-strain rate compressive behavior of a novel concrete with two different substituted recycled plastic aggregates. A reference mix with an average compressive strength of about 55MPa is considered. Recycled PolyEthylene Terephthalate (PET) powder and recycled mixed plastic (composed of PolyPropylene (PP) and PolyEthylene (PE)) granules were adopted to substitute fine and coarse aggregates. Two different substitution strategies are employed. In the first one, the PET powder is used to substitute the fine sand by volume. In the second one, the PET powder is used to substitute the fine sand while the recycled mixed plastic granules are used to substitute the coarse sand and fine coarse aggregates by volume (50% for PET powder and 50% for recycled mixed plastic granules). Four total replacement levels (5%, 10%, 20%, and 30%) by volume were considered. The fresh concrete properties (slump and density) and quasi-static compressive behavior, are investigated. The micro-scale characterization of the material using SEM scans provided a complete understanding of the observed macro-scale behavior. Tests were performed using conventional quasi-static loading with a compressive testing machine and high-strain rate tests with a Φ80-mm Split-Hopkinson Pressure Bar (SHPB) for strain rates up to 200s−1. The dynamic tests revealed the marked strain rate dependency, although specimens with large plastic volume substitution were more sensitive to the strain rate effect. A probabilistic data-driven model for the Dynamic Increase Factor (DIF) is also proposed based on the test data. Ultimately, this study indicates that the proposed material has a good high-strain rate compressive behavior and can be a promising material to be employed for protective techniques against impact and blast loads.

Meta-analysis on PET plastic as concrete aggregate using response surface methodology and regression analysis

This paper aims to thoroughly analyze the effect of polyethylene terephthalate (PET) plastic aggregate on concrete compressive strength using a meta-analysis. Forty-three datasets for concrete containing PET coarse aggregate and 60 data sets for concrete containing PET fine aggregate were collected. The input variables used were percentage and nominal maximum size of PET aggregate along with the concrete mix proportions. Main effect plots, contour plots, and surface plots of the expressions were presented to demostrate the effect of PET aggregate on the 28-day compressive strength of concrete. The statistical parameters of the regression equations, such as R2, adjusted R2 and root-mean-square error (RMSE), indicated that the RSM approach is a powerful tool to describe the change of concrete compressive strength by PET aggregate addition. In addition, the study showed that using PET plastic as a fine aggregate replacement performed better than using it as a coarse aggregate replacement in concrete. At up to 30% replacement, concrete containing PET plastic as a fine aggregate can have satisfactory compressive strength.

Study of the Effect of Plastic Aggregates on Drying Shrinkage and Expansion of Concrete

The aim of this work was to propose a possibility of using plastic aggregates from waste to reduce the shrinkage and expansion observed in concrete. The process of obtaining plastic aggregates was presented. Natural aggregates were partially substituted by plastic aggregates in the percentages: 0%, 5%, 10%, 20% and 30%. Drying shrinkage, water absorption and expansion tests were carried out on three families of concrete: control concrete (BT), concrete with addition of BAgP-PEHD high-density polyethylene plastic aggregate and with polyvinyl chloride BAgP-PVC. Given the slow appearance of the internal sulfate attack (ISA), an experimental technique was proposed to accelerate the appearance of this pathology. This technique involves heat treatment which stimulates the heating of the concrete at a young age, followed by a cycle of drying and cooling and ends with total immersion in water. The method of measuring expansions through sample image correlation was also proposed. The results showed an increased skrinkage of BAgP-HDPE compared to BT. On the other hand, a significant decrease in shrinkage was observed in BAgP-PVC samples. Water absorption increased in BAgP-HDPE and BAgP-PVC compared to BT. Greater expansion was observed at the cement paste-plastic aggregate interface than at the cement paste-natural aggregate interface. Given these properties, BAgP-PVC can be recommended for paving surfaces exposed to the hard weather conditions.

Recycled plastic (HDPE) coarse aggregate manufacturing method and performance in concrete

The process for preparing plastic aggregate to be used in concrete mixtures, The plastic can be reprocessed plastic that has been broken into strips after being washed through the templates. Sand and plastic rock dust aggregates are strong contenders for concrete mixes. This article uses recycled plastic collected from a local plastic shredder, measuring between 1 mm and 6 mm, melted at a temperature between 294 and 339 °C, and mixed with sand and rock dust. Here in this paper, scanning electron microscopy (SEM). And Elemental identification and quantitative composition information are also obtained using an “energy-dispersive X-ray analyzer” (EDX. or EDA). The size of the aggregates manufactured in the beginning varies. between 2.36 and 20 mm, which is covered with a granulometry under the ASCE-C330, C33-99a, and IS 383-2019 standards. In concrete, by use of light-weight plastic aggregates, as well as the use of high-density plastic materials to prepare plastic aggregates (single and well-graded), the method of manufacturing plastic aggregates for civil infrastructure, and the composition that incorporates this type of aggregate, are the concepts of this research.

Influence of Incorporating Waste Glass Powder and Fine Waste Plastic Aggregate on Fresh and Hardened Properties of Structural Concrete

This research aims to create green concrete with acceptable characteristics by recycling glass and plastic waste together. Cement was partially replaced with a 15% waste glass powder by weight mixture and fine aggregates with a 5% waste plastic crushed mixture. According to the findings, adding glass alone to concrete enhanced its qualities, such as compressive strength, splitting tensile strength, flexural strength, energy capacity, and bond strength, compared to a reference sample. The splitting tensile strength increases with replaced cement by 15% glass by 5.4%. When replacing fine aggregate with 5% fine plastic, splitting strength decreases by 5.4%. Flexural strength increased by 1.6% when adding 15% glass to the reference mixture. On the other hand, replacing sand with plastic for concrete with 15% glass powder led to some properties of concrete being affected downwards.

Experimental investigation along with 3-D Finite Element Analysis to determine the stress bearing ability of concrete containing waste plastic aggregates

Experimental investigation along with 3-D Finite Element Analysis to determine the stress bearing ability of concrete containing waste plastic aggregates

Mediating Effect of COVID-19 Pandemic on Single Use Plastic Production, Usage and Disposal Management Models Correlations

This research examines the consequences of the COVID-19 epidemic on the production, use, and disposal of single-use plastics. This research explores the intricate relationships between the impacts of COVD-19 on single-use plastic production, usage, and waste management with a focus on the mediating effects of the pandemic related to model parameters and correlations to develop a trustworthy approach. The report examines first the increasing evidence regarding the pandemic’s influence on various users and industries, and then the consequences for waste management and the environment. The research then examined the relationships and modelling framework correlations between the variables utilised to estimate the influence of COVID-induced changes in production, consumption, and management on single-use plastics. The study variables captured the influence of production, usage, and disposal on the environment. The study’s parameters are equally linked to types of usage, have a pronominal effect, and disposal plays a vital role in the environmental impact, which makes them extremely dynamic for parameters in this study. Single-use plastic aggregation in the environment is predicted to be a dominant mechanism by disposal behaviour.

Statistical optimization of fibre reinforced polymer concrete made with recycled plastic aggregates by central composite design

Statistical optimization of fibre reinforced polymer concrete made with recycled plastic aggregates by central composite design

Flexural behavior of composite T-beam made of plastic waste aggregate concrete web and high-strength concrete flange

The growth of post-consumed plastic waste needs recycling for new products. One of the methods of recycling is the use of plastic waste in concrete in the form of shredded aggregate and plastic fibers. Researches on the performance of structural members made of plastic waste recycled concrete are limited. In this study, a novel composite T-section beam made of high-strength concrete (HSC) for flange and plastic waste aggregate concrete (PWAC) for the web is investigated. Firstly, tests on materials were performed to measure compressive strength, tensile strength, shear transfer between the two concretes, and steel pull-out strength for the two concretes. Later, design of a composite T-beam was made for flexure, shear force, and shear connection between the flange and the web of the section. Results show that when PWAC is used to surround steel rebar, it affects the interfacial bond, and the steel will not yield. However, the first crack load will be high compared with the beams of tension steel surrounded by HSC . The design of shear connectors could be successful for the composite section using the ACI-PCI design procedure. Six composite T- beams were designed and tested. The mode of failure was found to be pure flexure and the test ultimate load capacity was found to be higher than the calculated one by a ratio between 1.295 and 2.212.

A Sustainable Alternative for Green Structural Lightweight Concrete: Performance Evaluation.

The use of structural lightweight concrete in the construction industry is on the rise in the last few decades mainly because of the higher strength per unit density, as it reduces the total deal load of the structural elements as compared with normal strength concrete. In addition, the environmental concerns of the concrete industry have gained supreme importance in recent times, demanding vital and effectual steps. In this regard, the current study was carried out to formulate an alternative approach for producing a sustainable lightweight structural concrete. The study followed two stages: initially, the selection of optimized manmade plastic aggregates based on trial concrete mixes, and finally, to gauge the physical-, mechanical- and durability related properties of the concretes integrating optimized manmade aggregate series at different replacement fractions. As a result of the first phase: two aggregate series out of eight were selected based on the compressive strength and durability properties of their concretes. In the next stage, all the properties for the optimized aggregate concrete were analyzed in terms of compressive strength. It was noted that the physical, mechanical and chloride penetration resistances have generally displayed a decreasing trend, with an increase in the manmade plastic aggregate replacement fractions as compared with reference lightweight concrete. However, the two aggregates, i.e., 70% DS-30% LLDPE and 50% QF-50% PET at the replacement fractions of 25% and 100%, were found to be the best two contenders that fulfilled the criteria for structural lightweight concrete, i.e., ASTMC330/C330M-14, and were proposed for structural lightweight purposes with low and relatively high strength and chloride resistance-based durability requirements, respectively. In addition, the brittleness ratios and structural efficiency parameters for the concretes of the 70% DS-30% LLDPE and 50% QF-50% PET also supplemented the aforementioned findings. Overall, this study presents a sustainable approach for the effective utilization of plastic waste for producing structural lightweight concrete.

Selected Mechanical and Physical Properties Concrete with Polypropylene Plastic Granule Aggregate

Amount of plastic use contribute significantly to the accumulation of plastic waste. The use of plastic waste in concrete is one of the world’s partial solutions for dealing with plastic waste. Polypropylene plastic granules are used as a partial replacement for fine aggregate in this study. The purpose of this research is to examine the physical and mechanical properties of the chosen base concrete while considering the potential of polypropylene plastic granules as a sand substitute in the concrete mixture. Variables to be investigated incorporate compressive strength, split tensile strength, workability, and density. The results of this study show that using polypropylene plastic granules as a substitute for fine aggregate at 10%, 20%, 30%, and 40% rates slump values of 8.1 cm, 8.4 cm, 8.6 cm, and 8.8 cm, respectively. However, it does not perform well in terms of compressive strength or split tensile strength. The strength reduction achieved by using 40% PP plastic granule can reach 58.06 percent.

Enhanced recyclability of waste plastics for waterproof cementitious composites with polymer-nanosilica hybrids

Waste plastics may be an environmentally friendly alternative to natural aggregates for concrete manufacture. However, the inferior bond strength between waste plastic aggregates and cement matrix greatly limits the uses of waste plastics for engineering designs and applications. Herein, ethylene–vinyl acetate (EVA) and nanosilica (nS) were jointly employed to enhance the matrix-aggregate interactions in cementitious composites with recycled waste plastics (RWPs). Waterproof properties of the cementitious composites with EVA and nS hybrids were measured. A non-destructive test using micro-focus X-ray computed tomography (µ-XCT) with contrast enhancing technique followed by microstructural tests (SEM/BSE and EDS) were conducted to in-situ trace liquid migration in the composite specimens. The single addition of EVA into the cementitious composites increased the porosity and depressed the compressive strength, but greatly decreased the water sorptivity by nearly 50 %. The organic–inorganic (EVA-nS) hybrids enhanced the recycling potential of the waste plastics in terms of the mitigated strength reduction and improved waterproofing performance. The coupled polymerization of EVA and nanofilling of nS effects were resolved to account for the recyclability improvement. The findings would shed light on design and fabrication of cementitious materials towards large scale recycling methods and technologies of waste plastics.

STUDY ON PERVIOUS CONCRETE PAVING BLOCK CONTAINING PLASTIC WASTE TYPE PET AS A SAND REPLACEMENT

This study reports the effects of using plastic waste type PET (Polyethylene Terephthalate) as sand replacement in the manufacture of pervious concrete paving block to be applied for low-traffic volume roads, parking areas and pedestrian walkways. The PET plastic aggregates were prepared through the pre-heated method under 150-180°C and then crushed into pieces to partially replace the sand content in concrete paving block mixtures at percentage of 5%, 10%, 20% and 30% by wt. of total sand. The experimental studies were conducted on concrete paving block (size 210x110x60 mm3) containing PET plastic waste aggregate. The coarse aggregate to cement ratio used was 4:1 while the fine aggregate to cement ratio was 1.5:1. The properties of concrete paving block specimens were evaluated based on the compressive strength, flexural strength, and void ratio results after curing. From the results obtained, it can be concluded that the maximum of percentage when using plastic waste type PET was 5% by wt. of sand. The mechanical properties and void ratio of the concrete paving block showed that the utilization of plastic waste type PET as construction material has potential contribution in improving the pavement structure and offering sustainable solution on environmental issue.

Effect of Polystyrene Waste on Concrete at Elevated Temperature

Objectives: The purpose of the present study is to examine the thermal and impact behaviour of the concrete containing polystyrene waste as aggregates. Methods: The concrete specimens were cast and cured in a conventional way to examine the mechanical behaviour of the concrete. A separate equipment was prepared to determine the impact strength of the concrete as per ASTM D5420-21. The thermal behaviour of the concrete with plastic aggregates were also examined with reference to IS 7861-1 (1975). Artificial Neural Network was also used to predict and compare the properties between both the conventional and plastic concrete. Findings: The mechanical behaviour of the concrete behaves well at Mix 2 when compared to other mixes. The impact strength of the concrete was found to be 98.375 J at Mix3 which was 20.69% higher than the Mix2. At Mix2 the 7 days compression strength in elevated temperature is 16.79 N/mm2 which was 4.8% higher than the Mix 1 and 31.74% higher than the Mix 3. At 28 days, the compressive strength of concrete containing 50% replacement of aggregate exposed to temperature 50oc for 24 hours is 26.84 N/mm2 which shows a better result and resistance in the thermal condition than the other mixes. ANN also gives reliable predicted values which exhibits a clear relation with the inclusion of the plastic aggregate and concrete matrix with some minimum errors. Novelty: From the experimental investigation it was observed that the plastic concrete fails in the transition zone of concrete due to the weaker bonding between the plastic aggregate and cement matrix. The plastic aggregate has not undergone any crushing failure in the concrete specimens when compared to the conventional aggregate. Thus, this solid polystyrene waste can be used as an alternative material for coarse aggregate in concrete. Keywords: Waste plastic; Modified concrete; Mechanical properties; Impact Strength; Thermal behaviour

Assessment of Sustainable Green Lightweight Concrete Incorporated in New Construction Technologies

Recent studies have led to the development of approaches for recycling plastic waste and using it as an alternative for natural aggregates in concrete. The studies mainly focused on the material properties and sustainability aspects of such implementation, with little focus on the financial implications and the technical feasibility. The purpose of this research is to investigate the different lifecycle costs associated with the use of green recycled plastic lightweight aggregates (GLACs) in concrete construction in different structural systems. For that purpose, the authors evaluated a concrete structure with several variable design systems and conducted structural design once using conventional concrete and once using concrete with recycled plastic aggregates, resulting in a total of 36 distinct scenarios. The lifetime cost analysis was performed on such scenarios. Finally, a sensitivity analysis was carried out to determine how structural characteristics and critical element costs influence cost-effectiveness. According to the findings, this approach can save up to 6% in life-cycle expenses. The findings of this research will contribute to the upcoming paradigm shift of using recycled plastic in concrete, which will reduce the environmental impacts of both the concrete and plastic industries while also assisting developers in lowering their life cycle costs.

Review of the Utilization of Plastic Wastes as a Resource Material in Civil Engineering Infrastructure Applications

The world is being burdened with excessive usage and indiscriminate dumping of plastic waste. The world presently produces nearly 400 million tons of plastic every year: less than 10% is recycled, 8% is incinerated, and the rest is dumped in landfills. The reduction of plastic has become a significant challenge due to the lower degradation rate. A substantial amount of this waste turns out to be litter in the oceans or landfills due to limited recycling or reuse in an environmentally friendly way. Compared with incineration and landfilling processes, recycling plastic waste is more productive. Hence, the utilization of plastic waste in civil engineering applications is found to have the maximum potential for consumption in bulk quantities, which can also help in minimizing disposal issues. This article reviews the characteristic properties of waste plastic and its utilization in civil engineering applications, specifically in bricks, blocks, road embankment, pavement layers, plastic aggregates, and voided slabs, which are systematically comprehended with various international standards. The use of waste plastic either retained or slightly improved the properties of the materials to which it is added. The paper also discusses the leaching properties of different kinds of plastic waste; their limitations along with probable opportunities associated with plastic waste utilization.

GEOMETRY OF RECENT RUPTURE ZONE AT СAPE RYTYI BASED ON GROUND PENETRATING RADAR (NORTHWESTERN COAST OF LAKE BAIKAL)

In here, we present the results of the GPR study of the modern rupture zone discovered earlier in the periphery of the Rita River delta flowing into Lake Baikal. The research was aimed at subsurface imaging of dislocation geometry using the Logis-Geotech OKO-2 radar equipped with the ABDL Triton antenna. As a result, the characterizations have been obtained for six 73 to 197 m long profiles across the rupture zone. All disturbances visible on the aerial photography materials are highlighted on the radargrams by the oblique reflection event due to a decrease in the signal amplitude. The rupture zone has two large segments – northeastern and submeridional, – which differ in zone width, number of discontinuities, dip angles, and displacement amounts. The deformation features can be attributed to different amounts of a plastic loamy aggregate of coarse deposits in different parts of the Rita River delta that is indirectly confirmed by weaker signal amplitudes on the northeastern segment. Based on present and previous studies, we proposed that the M=5.2 earthquake occurred on August 13, 1962, in Lake Baikal initiated the gravitational sinking in the Rita river delta edge by subsidence along gently sloped rupture surfaces on one segment and along steeply sloped ones on the other. It is necessary to identify and monitor such phenomena to prevent the development of emergencies associated with the collapse of the coasts of large water reservoirs.

Effect of Partial Replacement of Coarse Aggregate with Electronic Waste Plastic in Light Weight Concrete

This study assessed the usefulness of the replacement of coarse aggregate partially with electronic waste (e-waste) plastic in lightweight concrete since developing countries have been challenged with management of e-waste as well as high cost of coarse aggregates for concrete production. Coarse aggregates were replaced with e-waste plastic in concrete at 5%, 10%, 15%, and 20% for a concrete class of C20. The particle size distribution of the e-waste plastic aggregates was determined as well as the slump, compressive strength, water absorption and bulk density of the concrete. Generally, the slump decreased as the e-waste increased. The compressive strengths decreased for the 5% and 10% replacement of coarse aggregates with e-waste but increased for the 15% and 20% replacement of coarse aggregate with e-waste. 0% water absorption was obtained for the 15% and 20% e-waste content while the 10% e-waste concrete obtained 0.01% and the 5% e-waste obtaining of 0.013% after 28days of curing. The densities of 5%, 10%, 15% and 20% e-waste plastic content decreased as compared to the 0% e-waste plastic content. The values of compressive strength obtained showed that coarse aggregate replacements by e-waste plastic at 15% and 20% may be appropriate for lightweight concrete of class C20/25 since compressive strengths ranged between 16.09 Nmm–2 and 22.87 Nmm–2. This implies that partial replacement of coarse aggregate with e-waste plastic may be useful for lightweight concrete as well as helping in eradicating the environment of the menace of e-waste plastic.

Compressive and Flexural Strengths of Mortars Containing ABS and WEEE Based Plastic Aggregates.

The incorporation of plastic aggregates as a partial replacement of natural aggregates in cementitious materials is interesting in several ways. From a mechanical point of view, the partial substitution of sand with plastic aggregates could improve some properties (e.g., ductility, thermal insulation). This paper deals with the mechanical strength of mortars containing plastic aggregates as a partial replacement of sand. Part of the volume of sand in cement mortars is substituted with plastic aggregates which originate from WEEE (Waste from Electrical and Electronic Equipment) and consist of a mix of ABS (acrylonitrile-butadiene styrene), HIPS (high impact polystyrene) and PP (Polypropylene), or of monomaterial ABS from WEEE sorting. Three rates of replacement (by volume of sand) were tested: 10%, 15% and 30%. Mechanical tests were performed according to European standard EN196-1. The results show that compressive and flexural strength decrease with rate of replacement, but remain satisfactory for structural purposes. In addition, the density of mortar is reduced with the incorporation of plastic aggregates. The decrease of mechanical strength is mainly due to the weak bond between cement paste and plastic aggregates leading to the increase of porosity. Furthermore, it appears that mortars containing plastic aggregates could present a ductile rupture.