scholarly journals Towards More Sustainable Materials for Geo-Environmental Engineering: The Case of Geogrids

2021 ◽  
Vol 13 (5) ◽  
pp. 2585
Author(s):  
Alessio Cislaghi ◽  
Paolo Sala ◽  
Gigliola Borgonovo ◽  
Claudio Gandolfi ◽  
Gian Battista Bischetti

Plastic materials are widely used in geotechnical engineering, especially as geosynthetics. The use of plastic-based products involves serious environmental risks caused by their degradation. Innovative research has been focusing on biodegradable polymers of natural origin, especially on poly(lactic acid) (PLA), to reduce the use of plastics. This study aims to explore the potentiality of biopolymers for the production of geogrids, measuring the chemical and mechanical characteristics of raw materials and of prototype samples, similar to those available on the market. First, chemical composition and optical purity were determined by hydrogen nuclear magnetic resonance (1H-NMR) and polarimetry. Furthermore, samples of uniaxial and biaxial geogrids were custom-molded using a professional 3D printer. Mechanical properties were measured both on the filament and on the prototype geogrids. The maximum tensile resistance was 6.76 kN/m for the neat-PLA filament and 10.14 kN/m for uniaxial prototype geogrids produced with PLA-based polymer mixed with titanium dioxide. PLA-based materials showed higher tensile properties than polypropylene (PP), the most common petroleum derivative. Conversely, such biomaterials seem to be more brittle and with scarce elongation rate respect PP. Nonetheless, these results are encouraging and can support the use of PLA-based materials for innovative biodegradable geosynthetics production, especially if used in combination with live plants.

2018 ◽  
Vol 53 (6) ◽  
pp. 783-797 ◽  
Author(s):  
Daniele Battegazzore ◽  
Amir Noori ◽  
Alberto Frache

The paper describes the production and the mechanical characteristics of composites made completely of renewable raw materials. Several wastes or by-products from agro-industrial production namely hemp hurd, alfalfa, and grape stem were analyzed with respect to their thermal stability, morphological, and chemical composition in an attempt to validate their use in composites. Such natural particle fillers were used in the range of 10–50 wt% in combination with poly(lactic acid) by melt blending to obtain fully bio-based composites. These fillers were responsible for a noteworthy increase in the storage modulus. Furthermore, two micromechanical models (Voigt and Halpin–Tsai) were used to mathematically fitted the experimental data, and then the unknown moduli were extrapolated and compared with other natural fillers. Finally, the flexural strength of the bio-composites and the adhesion evaluation by exploiting Pukanszky’s model were carried out. As a result, the hemp hurd in the form of chips was the best investigated filler, which showed the highest calculated modulus of 10.5 GPa (Voigt) and the best filler–matrix interaction with “B” (Pukanszky’s coefficient) of 2.10. This information can be useful when comparison and selection of a suitable filler among the natural fillers are required.


2012 ◽  
Vol 200 ◽  
pp. 312-315
Author(s):  
Ping Zhang ◽  
Bing Tao Wang ◽  
De Gao ◽  
Li Hua Wen

The paper describes the production and the mechanical characteristics of composites made completely from renewable raw materials, the corn straw fiber and the biodegradable plastic, poly(lactic acid). The effect of straw fiber content on the mechanical properties of the composites was studied and the optimum mass fraction was 15%. To enhance the mechanical properties of the composites, two different methods were tested. Maleic anhydride as the compatilizer was introduced into the composites but the changes of the mechanical properties were small. While the other method, pre-treatment for straw fiber before blending, the mechanical properties increased obviously. The tensile strength and the impact strength were 35.6 MPa and 1.67 kJ/m2, respectively.


Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2237 ◽  
Author(s):  
P. R. Sarika ◽  
Paul Nancarrow ◽  
Abdulrahman Khansaheb ◽  
Taleb Ibrahim

Phenol–formaldehyde (PF) resin continues to dominate the resin industry more than 100 years after its first synthesis. Its versatile properties such as thermal stability, chemical resistance, fire resistance, and dimensional stability make it a suitable material for a wide range of applications. PF resins have been used in the wood industry as adhesives, in paints and coatings, and in the aerospace, construction, and building industries as composites and foams. Currently, petroleum is the key source of raw materials used in manufacturing PF resin. However, increasing environmental pollution and fossil fuel depletion have driven industries to seek sustainable alternatives to petroleum based raw materials. Over the past decade, researchers have replaced phenol and formaldehyde with sustainable materials such as lignin, tannin, cardanol, hydroxymethylfurfural, and glyoxal to produce bio-based PF resin. Several synthesis modifications are currently under investigation towards improving the properties of bio-based phenolic resin. This review discusses recent developments in the synthesis of PF resins, particularly those created from sustainable raw material substitutes, and modifications applied to the synthetic route in order to improve the mechanical properties.


2019 ◽  
Vol 303 ◽  
pp. 05001
Author(s):  
Mónica Bedoya ◽  
Federico Rivera ◽  
María Rico ◽  
David Vélez ◽  
Andrés Urrego ◽  
...  

It is clear that construction and demolition wastes (CDW) are constantly increasing throughout the world and these wastes can be used effectively to minimize the consumption of natural resources in the manufacture of more sustainable concrete. The CDW occupy an important segment of world waste production and its generation reached approximately 3 billion tons in 2012 in 40 countries [1]. Although this topic has been studied in the world, it is still valid for the reuse of waste that is constantly increasing, and although in many countries there are already examples of its use this type of concrete in Colombia and in the Medellìn city lacks applications. This project proposes the application of a sustainable concrete made with CDW and coal ash in the Medellín city for its implementation in the construction of urban furniture. A university community diagnosis of the needs in terms of furnishing was made. With the design reached, a modular chair was proposed to enable spaces within the university. The mechanical characteristics of the concrete and the design of the chair are evaluated and a simulation is done through finite elements to evaluate the viability of the proposed concrete, finding that with these properties is possible to manufacture durable and sustainable furniture that serves as an example for the application of sustainable materials


Polymers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 381
Author(s):  
Alessandro Nanni ◽  
Mariafederica Parisi ◽  
Martino Colonna

The plastic industry is today facing a green revolution; however, biopolymers, produced in low amounts, expensive, and food competitive do not represent an efficient solution. The use of wine waste as second-generation feedstock for the synthesis of polymer building blocks or as reinforcing fillers could represent a solution to reduce biopolymer costs and to boost the biopolymer presence in the market. The present critical review reports the state of the art of the scientific studies concerning the use of wine by-products as substrate for the synthesis of polymer building blocks and as reinforcing fillers for polymers. The review has been mainly focused on the most used bio-based and biodegradable polymers present in the market (i.e., poly(lactic acid), poly(butylene succinate), and poly(hydroxyalkanoates)). The results present in the literature have been reviewed and elaborated in order to suggest new possibilities of development based on the chemical and physical characteristics of wine by-products.


2020 ◽  
Vol 49 (6) ◽  
pp. 465-472
Author(s):  
S. Raj Sachin ◽  
T. Kandasamy Kannan ◽  
Rathanasamy Rajasekar

Purpose The purpose of this study is to carry out an investigation of the role of the wood particle size on the mechanical properties of poly lactic acid (PLA)-reinforced neem fiber biocomposite. Design/methodology/approach Composite test specimens were processed by reinforcing neem wood flour (NWF) in two different particle sizes, micro-sized NWF (MNWF) and nano-sized NWF (NNWF) separately into PLA. Composites were extruded at four different fiber loadings (10, 15, 20 and 25 Wt.%) into PLA matrix. The MNWF and NNWF had particle sizes varying from 5 to 15 µm and 10 to 15 nm, respectively. Findings Tensile strength, flexural strength and impact strength of PLA increased with fiber reinforcement for both the MNWF and NNWF cases. The NNWF-reinforced PLA composite at 20 Wt.% fiber loading proved to be the best composite that had outstanding mechanical properties in this research. Practical implications The developed composite can be used as a substitute for conventional plywood for furniture, building infrastructure and interior components for the automobile, aircraft and railway sectors. Originality/value A new biocomposite had been fabricated by using PLA and NWF and had been tested for its mechanical characteristics.


2011 ◽  
Vol 335-336 ◽  
pp. 1412-1417 ◽  
Author(s):  
Jiri Zach ◽  
Jitka Peterková ◽  
Vít Petranek ◽  
Jana Kosíková ◽  
Azra Korjenic

Production of building materials is mostly energy consuming. In the sphere of insulation materials we mostly see rock wool based materials or foam-plastic materials whose production process is demanding from material aspect and raw materials aspect as well. At present the demand for thermal insulation materials has been growing globally. The thermal insulation materials form integral part of all constructions in civil engineering. The materials mainly fulfill the thermal insulating functions and also the sound-insulating one. The majority of thermal insulation materials are able to fulfill both of the functions simultaneously. The paper describes questions of thermal insulation materials development with good sound properties based on natural fibres that represent a quickly renewable source of raw materials coming from agriculture. The main advantage of the materials are mainly the local availability and simple renewability of the raw materials. In addition an easy recycling of the materials after their service life end in the building construction and last but not least also the connection of human friendly properties of organic materials with advanced product manufacture qualities of modern insulation materials.


2020 ◽  
Author(s):  
Carlos Galhano ◽  
Pedro Lamas ◽  
Diogo Seixas

The massive growth of the ceramic industry and the consequent demand for construction materials worldwide has motivated the search for alternative solutions aimed at reducing the use of mineral / natural resources as the main source of raw materials. One of the strategies frequently adopted by the scientific community is the reuse of industrial waste. It is beneficial not only to reduce the overexploitation of mineral resources but also to reduce the environmental, economic and social impacts resulting from their incorrect disposal/treatment and consequent deposition on land unsuitable or that purpose. Duetoconsiderationssuchasphysico-mechanical characteristics and the high production rate, two different types of industrial waste were selected for this work, ashes resulting from the burning of coal in thermoelectric power plant, commonly known as bottom ash (B), and the Marble Powder (MP). It was intended to test the technological feasibility of the manufacture of ceramic materials produced from clay mixtures containing these two residues. For this purpose, the fine fraction(<63μm)obtained from the sieving of the marbleresidue(MR)and slag(Bf)was used,aswellasacoarsergrainslagfractionrangingfrom63-125μm(Bg). The resulting test samples were subjected to a firing of 950 °C under an oxidizing atmosphere, following a primary drying process. Faced with the standard values, the new ceramic materials obtained from MP have seen their mechanical and porous characteristics decrease and increase, respectively. Atthesametime,althoughtheadditionofBinno way influenced the mechanical characteristics,a significant improvement the porous characteristic was observed. The incorporation of these residues produced a color very close to the original sample material. Keywords: industrial waste, ceramic, construction materials, bottom ash, Marble Powder


2019 ◽  
Vol 10 (2) ◽  
pp. 75-86 ◽  
Author(s):  
Rita Ambarwati ◽  
Andre Saputro ◽  
Aditya Galih Fathurochman ◽  
As'ad Rizal

The research aimed to provide the solutions for the method of selecting product development strategies based on competitive advantage criteria including Quality, Cost, Delivery, Service, and Morale (QCDSM). The research was done in Micro, Small, and Medium Enterprises (MSMEs) of Ikat woven fabric in which the collecting data used questionnaires for the customers. The questionnaire was regarding the criteria for competitive advantage for MSMEs of Ikat woven fabric in Kediri. The analysis methods applied Importance-Performance Analysis (IPA) and Quality Function Deployment (QFD) based on the criteria of competitive advantage. The results show that the MSMEs of Ikat woven fabric should replace plastic materials into recyclable materials, ensure that raw materials do not contain dangerous and poisonous materials, choose coloring materials that do not contain dangerous and poisonous materials, choose the third parties to deliver products, weigh dye materials according to their composition and measurement, and utilize domestic raw materials.


2017 ◽  
Vol 4 ◽  
pp. 43-51
Author(s):  
Yuriy Suсhenko ◽  
Vladislav Suсhenko ◽  
Mikhail Mushtruk ◽  
Vladimir Vasyliv ◽  
Yuriy Boyko

Studies were conducted of the stressed-strained state of biopolymers of meat, which were exposed to the processes of elastic, residual and highly elastic deformation at cutting and mincing. Analysis of the structure of this natural biopolymer and the evaluation of mechanical characteristics of meat under normal and low temperatures are important factors that are taken into account for the rational selection of meat mincing machines and tools in the production of meat products, minced meat, semi-finished and sausage products. The structure of meat is a system of structured protein fibers, impregnated with tissue fluid, which is protein sol that contains organic and inorganic substances, soluble in it. The tissues that the meat is composed of belong to natural biopolymers, so conducting analytical studies into mechanical properties of meat within the framework of our understanding of the mechanics of polymers will make it possible to improve mincing processes, employed during manufacturing of meat products. In order to prevent meat overheating, the mincing process is performed at several stages. For example, in cutting mechanisms of choppers, they use a row of knives and grids with holes, diameter of which gradually changes from the original size of0.06 mto 0.003-0.002 min the outlet grids. Quality indicators of the finished products are affected by mechanical characteristics of raw materials and the way the cutting process is carried out. In the course of conducted analysis it was found that in modern food production there remain unresolved important problems, which address current issues, related to rheological and structural mechanical properties of meat raw material. First of all, it concerns theoretical and practical developments that enhance an understanding of physico-chemical and mechanical properties of raw materials, which will make it possible to develop theoretical foundations and experimentally substantiate the new conceptual approach to solving the task of improving the quality of semi-finished products and durability of equipment at meat processing enterprises of APC. The research is the basis for constructive and technological solutions, choice of mode, kinematic and dynamic parameters of cutting devices, steel and wear resistant coatings for cutting tools that provide saving of energy and materials at meat mincing, high quality of minced meat. and finished products and appropriate service life of the equipment. It was established that in order to determine characteristics of the strained state of meat, it is necessary to apply a circular diagram of loading-unloading, which allows analysis of behavior of the sample in a closed cycle of changing in external load. An analysis indicates a very large dependence of meat elasticity module on temperature. Dependences of this kind are generally characteristic of polymer bodies.


Sign in / Sign up

Export Citation Format

Share Document