Physico-mechanical Characterization Research Articles

Physico-mechanical Characterization of Stabilized Earth Blocks with Snail Shell and Termite Mound Powders as Pozzolanic Binders

The aim of this study is to reduce the reliance on cement in the construction of Stabilized Earth Blocks (SEBs) by assessing the addition of snail shell and termite mound powders as a partial substitute for cement. The focus of this study is on the valorization of local materials and animal waste in sustainable construction. Laterite, used as the base material, was stabilized by substituting 0 to 80% of the cement with snail shell and termite mound powders to create blocks that were tested for their mechanical strength and water absorption. The results show that the compressive strength of the blocks remains above the required threshold of 4 MPa up to a 50% substitution, with a downward trend at higher rates. The capillary water absorption of the stabilized earth blocks remains within the limits of blocks classified as low-absorption, with coefficients ranging from 0.58 kg/m²/min at a 50% substitution to 1.14 kg/m²/min at an 80% substitution. These findings suggest that a substitution up to 50% could represent an adequate balance between mechanical performance and environmental benefits, thus ensuring the required durability and mechanical strength. Although the research is limited to the study of these materials in their raw state, future work could explore the enhancement of the pozzolanic activity of snail shell and termite mound ash through treatments such as calcination to further strengthen the eco-efficiency of the process.

Cell viability assessment and physicomechanical characterization of Juglans regia leaf fiber-reinforced poly(hydroxybutyrate) films for biomedical uses

Cell viability assessment and physicomechanical characterization of Juglans regia leaf fiber-reinforced poly(hydroxybutyrate) films for biomedical uses

Physico-Mechanical Characterization of Masonry Mortars for Sustainable Construction: Experimental Study with Four Different Aggregates

The construction sector generates a strong environmental impact every year as a result of the high consumption of raw materials and the large waste volumes associated with this productive activity. In this sense, the search for alternative and sustainable solutions that allow progress towards responsible economic growth has become a priority activity. This work presents an exhaustive characterisation of masonry mortars made with four different types of aggregates: standard sand, natural sand, concrete waste recycled sand and ceramic components recovered sand. Differently from other studies, this research addresses the previous characterisation of the aggregates as raw material for the manufacture of masonry mortars, and, afterwards, a study of the most relevant properties for these cement composites in the fresh and hardened state is carried out. The most relevant properties of the mortars made with these raw materials are presented, and the repercussion of aggregate washing on their physical-mechanical characteristics is analysed. The results show how mortars made with 100% recycled aggregate can be competitive in the industry, presenting excellent properties in the fresh state and achieving an optimal mechanical strength. In addition, it has been observed that the introduction of a previous washing step of the aggregates improves their physical-mechanical properties and results in a higher quality of the cement mortars finally produced. In this way, the most representative properties of this type of materials have been collected in a well-structured and complete way, thus showing their possibilities of application in the construction industry.

Investigation of Weathering Resistance and Damage Manifestations of Mortar Formulations for Heritage Structures in Saline Environment

ABSTRACT Salt, moisture, wind, relative humidity, and temperature fluctuations accelerate the deterioration of heritage masonry mortars. The salt entering the structure crystallizes on water evaporation, resulting in efflorescence and cryptoflorescence. As the conservation of built heritage primarily focuses on protecting the structure’s functionality, durability, and compatibility with the materials, salt weathering resistance must be emphasized when choosing a repair material for conservation. This study investigates the resistance of five different mortar compositions to salt exposure. Mortar cubes of size 50 mm were cast using five different binder compositions — dry hydrated lime, lime aged for one month, lime aged for one year, lime mortar with 20% Ordinary Portland Cement by weight and lime mortar with 50% Ordinary Portland Cement by weight. Alternate wetting and drying cycles were simulated by immersing the cubes in a 10% anhydrous sodium sulphate solution followed by drying. Physicomechanical characterization of the mortar was conducted before weathering. X-ray diffraction and Scanning Electron Microscopy provided the mineralogical and morphological alterations of the mortar specimens with weathering, respectively. Along with the microstructural assessment, observations on the mass change during the weathering cycles indicated that the partial replacement of lime with cement improved the weathering resistance of the mortar by changing the pore structure of the matrix. However, salt weathering resistance was unaffected by the changes in the ageing duration of lime. The study provides options for alternative lime-based systems with enhanced salt weathering resistance and investigates the role of the compositional differences and their impact on the pore structure and strength of the matrix, which in turn governs the salt weathering resistance.

Physico-mechanical characterization of eco-friendly gypsum composites incorporating shredded surgical face masks

Physico-mechanical characterization of eco-friendly gypsum composites incorporating shredded surgical face masks

Fabrication and Physico-mechanical Characterization of Short Natural/Synthetic Fiber–Reinforced Hybrid Composites: Effects of Biodegradation and Chemical Aging

The main goal of this study was to develop eco-friendly and low-cost multiple short natural fiber-reinforced hybrid composites with the hybridization of comparatively high-strength glass fibers. The hybrid composites were fabricated via hand lay-up by using short jute, silk, water hyacinth, and glass fibers for the reinforcements and unsaturated polyester resin for the thermoset polymer matrix. The reinforcing fibers were randomly oriented, and five types of hybrid composites were fabricated with different types of fiber content (wt.%). The performance of the manufactured hybrid composites was assessed by tensile, flexural, and impact testing, as well as water uptake (%). It was revealed that composites with high glass fiber content (wt.%) exhibited optimum mechanical performance in most cases, while poor moisture resistance performance was exhibited for the hybrid composites containing higher natural fibers (wt.%). The hybrid composite samples were also aged in soil medium (biodegradation) for 25 days and different chemical solutions (alkaline, acidic, and salt) for 10 days. After biodegradation, the drop of tensile strength (TS) and tensile modulus (TM) was revealed to be approximately 38–61 and 58–72%, respectively. On the other hand, after chemical aging, the drop of TS and TM was exhibited to be approximately 49–76% and 51–65%, respectively, for alkali solution aging; 42–75% and 29–76%, respectively, for acid solution aging; and 43–59% and 51–65%, respectively, for salt solution aging.

Comparative Studies of the Physico-Mechanical Characterization of Ugwuoba Clay with Admixtures of Corncob and Sugarcane Bagasse Ashes

An investigation into the effects of combustible materials on the refractory properties of Ugwuoba clay, using sugarcane bagasse ash and corncob ash has been undertaken. Ugwuoba clay was sourced from Ugwuoba town in Oji River Local Government Area of Enugu State. Sugarcane bagasse were collected at Lokpanta, a Fulani settlement in Okigwe Community, Imo State, while corncobs were collected at New Artisan Market in Enugu Metropolis. The clay was processed using standard beneficiation and purification procedures at the Ceramics Department of Projects Development Agency (PRODA), Enugu. The sugarcane bagasse and corncobs were each and separately calcined into amorphous ash by heating in a furnace at 650oC. The refractory blends were compounded at the ratio of 90:10, 80:20, 70:30, and 60:40 for Ugwuoba clay (UGC) to Sugarcane Bagasse Ash (SBA) and Ugwuoba Clay (UGC) to Corncob Ash (CCA) separately and respectively. These blends were subsequently molded into the standard test pieces for the various properties determination and subjected to firing at temperatures of 900oC, 1000oC, 1100oC and 1200oC. Thereafter, the fired samples were characterized for fired shrinkages, total shrinkages, apparent porosities, water absorption coefficients, apparent densities, bulk densities and moduli of rupture. The results obtained for each of the blends showed that the values were within the tolerable limits for industrial refractories with the 10%SBA and the 20%CCA blends showing the best results. Comparatively however, the 10%SBA produced the better of these properties than the 20%CCA. A conclusion is drawn to the effect that both sugarcane bagasse ash and corncob ash can serve as good organic admixtures for refractory bricks production for the lining of melting furnaces in the metals industry, hence opening new frontiers for recycling of these agricultural wastes for environmental safety and economic development in Nigeria.

Morphological and physicomechanical characterization of synthetic and natural fibers

Morphological and physicomechanical characterization of synthetic and natural fibers

Physico-mechanical characterization of Higher Himalayan granite under the thermal treatments of different heating–cooling conditions

Physico-mechanical characterization of Higher Himalayan granite under the thermal treatments of different heating–cooling conditions

Eco-Design and Characterization of Sustainable Lightweight Gypsum Composites for Panel Manufacturing including End-of-Life Tyre Wastes.

The incorporation of rubber recycled aggregates from end-of-life tyres (ELT) in the manufacturing process of sustainable building materials has gained great interest in recent decades as a result of the large volume of this waste being generated annually. In this work, the objective is to make a contribution towards the circularity of construction products by carrying out a physico-mechanical characterisation of new gypsum composites made with the incorporation of these recycled rubber aggregates. To this end, up to 30% by volume of the original raw material has been substituted, analysing the mechanical resistance to bending and compression. Although lower than those of traditional gypsum material, both properties exceed the limits set at 1 and 2 MPa, respectively, by the current regulations. In addition, water absorption by capillarity significantly decreases, and thermal conductivity is reduced by more than 35% with respect to the reference material. Finally, in order to provide the research with a practical application, a prefabricated plate design has been proposed that incorporates the gypsum materials studied and an agglomerated rubber band that increases the thermal resistance and improves the efficiency of the designed construction system. In this way, this research reflects the potential of these novel building materials and explores new avenues for their application in building construction.

Synthesis and Physico-mechanical Characterization of Polystyrene Blended with Uvaria chamae Seed Oil (UCSO) Used as a Plasticizer

Polystyrene has long been recognized as a versatile and cost-effective material used in several industries, such as packaging, consumer electronics, building, medical, and and food service disposables. The current research focuses on the synthesis and physico-mechanical characterization of polystyrene blended with Uvaria chamae seed oil (UCSO), used as a plasticizer. UCSO was extracted with hexane and used as a plasticizer in the suspension polymerization of styrene. The findings on the quality of the oil are as follows: oil content (12.54%), specific gravity at 25 oC (0.94 ± 0.00), acid value (8.029 ± 0.12 mg KOH), iodine value (18.987 ± 0.40), peroxide value (7.0), free fatty acid (4.015%), and saponification values (173.392). The mechanical properties of the polystyrene blend with Uvaria chamae seed oil (PS-UCSO) at 100g were reported as follows: ultimate tensile strength (48.6 MPa), Young modulus (1985.3 MPa), % elongation (12.6%), break load (390.6 N), peak load (386.5 N), Shore D hardness (80.0), and water absorption (1.31%). Other properties like thermal conductivity and thermal resistance were reported as 0.2614 (W/m.K.) and 3.8256 (1/k). The findings revealed that the mechanical properties of PS-UCSO were highly competitive with the conventional white petroleum oil used as a plasticizer. As a recommendation, Uvaria chamae seed oil should be used as a plasticizer since it is available, cheap, and environmentally friendly.

Initiative to Increase the Circularity of HDPE Waste in the Construction Industry: A Physico-Mechanical Characterization of New Sustainable Gypsum Products

The annual production of plastic waste worldwide has doubled in just two decades, with approximately 390 million tonnes of plastic waste now being generated. In this context, the construction industry must move towards the development of new, more sustainable materials made under circular economy criteria. In this work, a physico-mechanical characterisation of gypsum composites with the incorporation of high-density polyethylene (HDPE) waste, replacing 2–4–6–8–10% by volume of the original raw material, has been conducted. The results show how the incorporation of these plastic wastes improves the water resistance of the gypsum material without additions, as well as producing a decrease in thermal conductivity and greater resistance to impact. On the other hand, it has been found that, as the percentage of recycled raw material added increases, the mechanical resistance to bending and compression decreases, leading to fracture due to a lack of cohesion between the matrix and the waste. Nevertheless, in all the cases studied, mechanical strengths higher than those established by the EN 13279-2 standard were obtained. Thus, the results confirm the viability of these secondary raw materials to be used in the development of new products for sustainable building, especially in the design of prefabricated panels for false ceilings.

Physico-Mechanical Characterization of Recycled Waste Tire Rubber and Rice Straw Reinforced Composite

Physico-Mechanical Characterization of Recycled Waste Tire Rubber and Rice Straw Reinforced Composite

Physicomechanical Characterization of a Novel Resin-Modified Glass Ionomer Luting Cement Functionalized with a Phosphate Functional Monomer

Background. Resin-modified glass ionomer cements (RMGICs) are characterized by their ability to chemically bond with the tooth structure and their fluoride release, making them commonly used to retain indirect restorations. However, inferior mechanical properties and solubility (SO) are their main drawbacks compared to the most recent resin-based cement. Aim of the Study. Formulate a novel brand of experimental RMGIC (eRMGIC), based on RMGIC by incorporating 2-(methacryloxy) ethyl phosphate (2-MEP), an organophosphorus monomer with the potential to enhance mechanical properties along with low SO. Materials and Methods. eRMGICs were prepared by the inclusion of 2-MEP monomer with different weight percentages (0–40 wt%) into the RMGIC’s liquid (Fuji PLUS, GC. Corp.), then their compressive strength (CS), flexural strength (FS), film thickness (FT), setting time (ST), SO, and water sorption were examined and compared to the conventional RMGIC. Furthermore, a scanning electron microscope analyzed their surface homogeneity and integrity. Shapiro–Wilk test of normality was used to analyze data, one-way analysis of variance, Dunnett T3, and Tukey’s honest significant difference post-hoc tests. Results. After 28 days and 180 days of storage, the values of CS of the eRMGICs were significantly higher. However, after 24 hr of storage, the values were comparable to the control group. The FS results showed a double-fold increase in different concentrations of eRMGICs through all the time intervals ( p < 0.001 ) compared to conventional RMGIC. Furthermore, the inclusion of 2-MEP increased water uptake and decreased SO. The FT of experimental eRMGICs cement showed a statistically significant increase with increasing 2-MEP concentration. However, it was within the specification given by ISO 9917-1:2007. There was a decrease in the ST of eRMGICs compared to control cement; however, it was within the specification given by ISO 9917-2:2017. Conclusions. 2-MEP monomer showed encouraging results and could be used in producing new (eRMGICs) with enhanced physicomechanical properties, which can increase the longevity of cement and improve its ability to resist occlusal stresses without fracture.

Investigation of gypsum composites with different lightweight fillers: A physico-mechanical characterisation regarding possibilities for building applications

This paper shows the characterization of a new lightened gypsum-based material for use in buildings. Super absorbent polymer (SAP) Potassium Polyacrylate has been used as main lightener leading to a 20% density reduction. In addition, tests have been carried out with the lightened plaster material reinforced with vermiculite (VER), recycled glass wool (RGW), expanded clay (EC). A significant improvement in physical properties was achieved. After material evaluation, a new precast design was elaborated and tested for its use in building. Physical-mechanical properties of these new material have been studied. A complementary ignitability test was also conducted to set this material's suitability for its use in building. All samples performed over standard minimum requirements. Samples containing RGW obtained best results in both, thermal conductivity, and acoustic absorption.

Biodegradable nano-reinforced packaging with improved functionality to extend the freshness and longevity of Plums Oemleria cerasiformis

Food packaging reinforced with Zn-doped TiO2 nanoparticles with enhanced prerequisite film-forming and biodegradable traits was prepared to augment fresh food storage. Pure and tailored metal (Zinc, Copper, and Selenium) doped TiO2 nanoparticles were synthesized and analyzed through multiple characterization techniques (optical spectra, XRD patterns (X-Ray Diffraction), Dynamic Light Scattering, and Scanning Electron Microscopy). The synthesized nanoparticles were tested for their Minimum Inhibitory Concentrations, antimicrobial potential against common lethal food pathogens, and cytotoxicity. Compared to Cu- and Se-doped nanoparticles, Zn-doped TiO2 nanoparticles displayed the most potent antimicrobial activity with insignificant cytotoxicity and were incorporated into the food packaging materials. The developed nano-reinforced food packaging efficaciously augmented the freshness of plums (Oemleria cerasiformis) for 16 days (42 ± 2 °C). The physicomechanical characterization of the nano-reinforced packaging establishes its utility in food packaging applications. The developed biodegradable packaging undergoes complete decomposition within 12 days of storage in natural soil.

Physico-Mechanical Characterization of Cement Concrete using Quarry Waste as Fine Aggregate Replacement of Natural Sand

Physico-Mechanical Characterization of Cement Concrete using Quarry Waste as Fine Aggregate Replacement of Natural Sand

Physico-mechanical characterisation of basecoats for tailored UV-cured multilayered wood coating systems

The durability and aesthetic properties of wood flooring arise from the properties of the coating applied on its surface. Due to their fast-curing speed, high crosslinking density and high durability, UV-curable coatings are often preferred for flat surfaces such as hardwood flooring, tabletops and doors. In the case of hardwood flooring, several types of deteriorations on the coating surface can shatter the perception of the whole product. In the present work, UV-curable formulations with various monomer-oligomer couples were prepared and used as a basecoat within a multilayered wood finishing system. While the topcoat is designed to endure most of the in-use loads, elastic and plastic stresses can reach deeper layers. The aim of this study is to analyze the influence of basecoat composition and thickness on the mechanical behavior of a UVcurable multilayered wood finishing system. First, physical properties such as the average theoretical segment length, glass transition temperature and crosslinking density, of standalone films of the various monomer-oligomer couples were investigated. Then, indentation and scratch resistance tests were performed to understand the role of the basecoats in the overall mechanical response of the multilayered coatings. The thickness of the basecoat applied was found to have a great influence on the mechanical resistance of the finishing system. No direct correlation was established between the basecoat as standalone films and within the multilayered coatings, considering the complexity of such systems several behaviors were detected. A finishing system able to promote overall good scratch resistance and good indentation modulus was obtained for a formulation displaying an equilibrium between the network density and the elasticity.

Polyacrylamide hydrogel-based nanocomposites containing graphene, kaolin or laponite: Physico-mechanical characterization and adsorption properties

Polyacrylamide hydrogel-based nanocomposites containing graphene, kaolin or laponite: Physico-mechanical characterization and adsorption properties

Waste Cork in Metakaolin–Geopolymer Matrix: Physico-Mechanical Characterization

Cork powdery waste (CW) from agglomerated cork caps manufacturing is commonly transported to waste-to-energy plants, although it could be locally exploited for lightweight building materials. The transformation of CW into a geopolymer formulation to obtain a novel composite formulation suitable for insulating panels is presented in this contribution. The geopolymer mix was based on metakaolin added to NaOH and Na silicate solutions, to which 2.4, 4.8 and 9.1 wt% (calculated upon dry metakaolin) of CW in the form of as-received powdery waste were added. No pre-treatments were performed on CW and no thermal curing was conducted for the alkali-activated product that was consolidated at room temperature to improve product sustainability. The insulating panel presented an apparent density of about 1.521 to 0.990 ± 0.001 g/cm3, combined with a total porosity in the range of 35.61 to 56.22 ± 0.003 % for 2.4 to 9.1 wt% of CW, respectively, and this was dependent upon ageing time. The values of its mechanical properties (compressive strength ranged from 2.5 to 1.5 MPa at 28 and 90 days of curing time, complying with UNI EN 998-2) and thermal insulating properties (thermal conductivity around 0.1146 W/mK) indicated that the highest percentage of CW in the formulations, i.e., 9.1 wt%, was suitable to obtain self-standing insulating panels.