Factors That Affect the Mechanical Strength of Archaeological Wood—A Case Study of 18th-Century Wooden Water Pipes from Bóżnicza Street in Poznań, Poland

Large amounts of archaeological wood are often excavated during groundworks in cities and towns. Part of the unearthed artefacts is usually saved, conserved and then presented in museums. However, if the finding contains several similar objects, some of them could potentially be further employed for some other practical purposes. The research aimed to determine the mechanical performance of the remains of wooden water mains excavated at Bóżnicza street in Poznań, Poland and evaluate its potential usefulness for any practical purposes. First, wood density was determined along with its mechanical strength in compression. The density of archaeological wood identified as Scots pine was lower than contemporary pinewood (383 kg × m−3 vs. 572 kg × m−3); therefore, its mechanical properties in compression tests were also lower, as expected, making the wood unsuitable for any practical applications. However, the differences in modulus of elasticity and compressive strength were not justified by the differences in wood density. Further infrared spectroscopy and X-ray diffraction analyses revealed additional differences in chemical composition and cellulose crystallinity between archaeological and contemporary wood. The results indicated the decrease in carbohydrate content and cellulose crystallinity in degraded wood, which, in addition to wood density, apparently contribute to the deterioration in mechanical strength of archaeological wood. The case study of the excavated archaeological wooden pipes shows that they have historical value but are not useful for practical purposes. It also revealed that not only wood density but also its chemical composition and cellulose crystallinity level has a substantial impact on the wood mechanical properties, particularly in compression.

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Weldability - Behavior of Welded Reinforcement

Revista de Chimie ◽

10.37358/rc.19.10.3469 ◽

2019 ◽

Vol 70 (10) ◽

pp. 3469-3472

Keyword(s):

Mechanical Properties ◽

Chemical Composition ◽

Mechanical Characteristics ◽

Mechanical Performance ◽

Current Work ◽

Carbon Equivalent ◽

Work Process ◽

Ultimate Limit

Weldability involves two aspects: welding behavior of components and safety in operation. The two aspects will be reduced to the mechanical characteristics of the elements and to the chemical composition. In the case of steel reinforcing rebar’s, it is reduces to the percentage of Cech(carbon equivalent) and to the mechanical characteristics: the yielding limit, the ultimate limit, and the elongations which after that represent the ductility class in which the re-bars is framed. The paper will present some types of steel reinforcing rebar’s with its mechanical characteristics and the welding behavior of those elements. In the current work, process-related behavior of welded reinforcement, joint local and global mechanical properties, and their correlation with behavior of normal reinforcement and also the mechanical performance resulted in this type of joints. Keywords: welding behavior, ultimate limit, reinforcing rebar’s

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Experimental investigation of the mechanical behavior of glass fiber/high fluidity polyamide-based composites for automotive market

Journal of Reinforced Plastics and Composites ◽

10.1177/07316844211014006 ◽

2021 ◽

pp. 073168442110140

Author(s):

Hossein Ramezani-Dana ◽

Moussa Gomina ◽

Joël Bréard ◽

Gilles Orange

Keyword(s):

Mechanical Properties ◽

Glass Fiber ◽

Mechanical Performance ◽

Physical And Mechanical Properties ◽

Ultimate Strain ◽

Uniaxial Tensile ◽

Compression Tests ◽

Automotive Market ◽

Glass Fiber Reinforced ◽

Glass Fiber Reinforcement

In this work, we examine the relationships between the microstructure and the mechanical properties of glass fiber–reinforced polyamide 6,6 composite materials ( V f = 54%). These materials made by thermocompression incorporate different grades of high fluidity polyamide-based polymers and two types of quasi-UD glass fiber reinforcement. One is a classic commercial fabric, while the other specially designed and manufactured incorporates weaker tex glass yarns (the spacer) to increase the planar permeability of the preform. The effects of the viscosity of the polymers and their composition on the wettability of the reinforcements were analyzed by scanning electron microscopy observations of the microstructure. The respective influences of the polymers and the spacer on the mechanical performance were determined by uniaxial tensile and compression tests in the directions parallel and transverse to the warp yarns. Not only does the spacer enhance permeability but it also improves physical and mechanical properties: tensile longitudinal Young’s modulus increased from 38.2 GPa to 42.9 GPa (13% growth), tensile strength increased from 618.9 MPa to 697 MPa (3% growth), and decrease in ultimate strain from 1.8% to 1.7% (5% reduction). The correlation of these results with the damage observed post mortem confirms those acquired from analyses of the microstructure of composites and the rheological behaviors of polymers.

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Mechanical properties and microstructure of recycled mortar reinforced with hybrid fiber

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i4.12279 ◽

2018 ◽

Vol 7 (4) ◽

pp. 2178 ◽

Cited By ~ 2

Author(s):

Sallehan Ismail ◽

Mohammad Asri Abd Hamid ◽

Zaiton Yaacob ◽

Dzulkarnaen Ismail ◽

Hazizan Md Akil

Keyword(s):

Mechanical Properties ◽

Flexural Strength ◽

Mechanical Strength ◽

Mechanical Performance ◽

Volume Fraction ◽

High Strength ◽

Strength Properties ◽

Recycled Aggregate ◽

Hybrid Fiber ◽

Hybrid Fibers

This study investigated the hybrid effects of two types of microfiber, namely, polypropylene and nylon, on the mechanical properties of high-strength mortar, which produced fine recycled aggregate (FRA). The amount of microfibers was maintained at a volumetric fraction of 0.6%. The microstructure and mechanical strength properties (compressive strength and flexural strength) of recycled mortar reinforced with hybrid-size microfibers were evaluated at various curing ages. Experimental results show that the inclusion of hybrid fibers significantly influenced the mechanical performance of the recycled mortar. The hybridization fiber at volume fraction 0.3% polypropylene + 0.3% nylon yielded the most promising mechanical performance. Enhancements of 8% on compressive and 11% flexural strength were achieved at 28 days. Scanning electron microscopy observations revealed that reinforcement at the microscale prohibited the initiation and growth of cracks at the micro level. High loads were required to form macrocracks within composites, thereby improving the mechanical strength of the mortar matrix.

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Influence of wire arc additive manufacturing of Ti-6Al-4V on microstructure and mechanical properties for potential large-scale aviation parts

MATEC Web of Conferences ◽

10.1051/matecconf/202032103037 ◽

2020 ◽

Vol 321 ◽

pp. 03037

Author(s):

D. Elitzer ◽

H.W. Höppel ◽

M. Göken ◽

D. Baier ◽

C. Fuchs ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Additive Manufacturing ◽

Mechanical Strength ◽

Large Scale ◽

Solution Treatment ◽

Compression Tests ◽

Process Gas ◽

Relationship Of ◽

Wire Arc Additive Manufacturing

As one of the most common Titanium alloys, Ti-6Al-4V faces new challenges concerning the ecological footprint. Due to the current processes, a high metal chip pollution leads to a Buy-to-Fly of 25:1. In this study the parameter / microstructure relationship of Ti-64 on the mechanical properties are discussed. Wire Arc Additive Manufacturing (WAAM) was applied to build samples for microstructural analyses and compression tests. A stress relief (SR) and a solution treatment and annealing (STA) was performed. It was found that SR had no influence on multi-layered samples due to intrinsic heat-treatment. A STA heat-treatment led to a reduction in the mechanical strength. Helium as process gas resulted in an increased mechanical strength due to higher heat capacity compared to argon.

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Investigation and Statistical Modeling of the Mechanical Properties of Additively Manufactured Lattices

Materials ◽

10.3390/ma14143962 ◽

2021 ◽

Vol 14 (14) ◽

pp. 3962

Author(s):

Derek G. Spear ◽

Anthony N. Palazotto

Keyword(s):

Mechanical Properties ◽

Mechanical Performance ◽

Design Parameters ◽

Statistical Experimental Design ◽

Lattice Structures ◽

Compression Tests ◽

Static Compression ◽

Interaction Terms ◽

Cell Densities ◽

The Impact

This paper describes the background, test methodology, and experimental results associated with the testing and analysis of quasi-static compression testing of additively manufactured open-cell lattice structures. The study aims to examine the effect of lattice topology, cell size, cell density, and surface thickness on the mechanical properties of lattice structures. Three lattice designs were chosen, the Diamond, I-WP, and Primitive Triply Periodic Minimal Surfaces (TPMSs). Uniaxial compression tests were conducted for every combination of the three lattice designs, three cell sizes, three cell densities, and three surface thicknesses. In order to perform an efficient experiment and gain the most information possible, a four-factor statistical experimental design was planned and followed throughout testing. A full four-factor statistical model was produced, along with a reduced interactions model, separating the model by the significance of each factor and interaction terms. The impact of each factor was analyzed and interpreted from the resulting data, and then conclusions were made about the effects of the design parameters on the resultant mechanical performance.

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3D Printing of Thermoplastic Elastomers: Role of the Chemical Composition and Printing Parameters in the Production of Parts with Controlled Energy Absorption and Damping Capacity

Polymers ◽

10.3390/polym13203551 ◽

2021 ◽

Vol 13 (20) ◽

pp. 3551

Author(s):

Marina León-Calero ◽

Sara Catherine Reyburn Valés ◽

Ángel Marcos-Fernández ◽

Juan Rodríguez-Hernandez

Keyword(s):

Mechanical Properties ◽

Chemical Composition ◽

3D Printing ◽

Energy Absorption ◽

Thermoplastic Elastomers ◽

Damping Capacity ◽

Compression Tests ◽

Wide Range ◽

Printing Parameters

Additive manufacturing (AM) is a disruptive technology that enables one to manufacture complex structures reducing both time and manufacturing cost. Among the materials commonly used for AM, thermoplastic elastomers (TPE) are of high interest due to their energy absorption capacity, energy efficiency, cushion factor or damping capacity. Previous investigations have exclusively focused on the optimization of the printing parameters of commercial TPE filaments and the structures to analyse the mechanical properties of the 3D printed parts. In the present paper, the chemical, thermal and mechanical properties for a wide range of commercial thermoplastic polyurethanes (TPU) filaments were investigated. For this purpose, TGA, DSC, 1H-NMR and filament tensile strength experiments were carried out in order to determine the materials characteristics. In addition, compression tests have been carried out to tailor the mechanical properties depending on the 3D printing parameters such as: infill density (10, 20, 50, 80 and 100%) and infill pattern (gyroid, honeycomb and grid). The compression tests were also employed to calculate the specific energy absorption (SEA) and specific damping capacity (SDC) of the materials in order to establish the role of the chemical composition and the geometrical characteristics (infill density and type of infill pattern) on the final properties of the printed part. As a result, optimal SEA and SDC performances were obtained for a honeycomb pattern at a 50% of infill density.

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Weldability - Behavior of Welded Reinforcement

Revista de Chimie ◽

10.37358/rc.19.10.7577 ◽

2019 ◽

Vol 70 (10) ◽

pp. 3469-3472

Author(s):

Anamaria Feier ◽

Oana Roxana Chivu ◽

Augustin Stoica

Keyword(s):

Mechanical Properties ◽

Chemical Composition ◽

Mechanical Characteristics ◽

Mechanical Performance ◽

Current Work ◽

Carbon Equivalent ◽

Work Process ◽

Ultimate Limit

Weldability involves two aspects: welding behavior of components and safety in operation. The two aspects will be reduced to the mechanical characteristics of the elements and to the chemical composition. In the case of steel reinforcing rebar�s, it is reduces to the percentage of Cech(carbon equivalent) and to the mechanical characteristics: the yielding limit, the ultimate limit, and the elongations which after that represent the ductility class in which the re-bars is framed. The paper will present some types of steel reinforcing rebar�s with its mechanical characteristics and the welding behavior of those elements. In the current work, process-related behavior of welded reinforcement, joint local and global mechanical properties, and their correlation with behavior of normal reinforcement and also the mechanical performance resulted in this type of joints.

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Mechanical and Durability Properties of Lightweight Foamed Concrete Containing Palm Kernel Shell

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i3.9.15277 ◽

2018 ◽

Vol 7 (3.9) ◽

pp. 65 ◽

Cited By ~ 1

Author(s):

Hanizam Awang ◽

Adebayo Adeshina Dauda ◽

Wenny Arminda

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Mechanical Strength ◽

Mechanical Performance ◽

Palm Kernel ◽

Dry Density ◽

Palm Kernel Shell ◽

Durability Properties ◽

Foamed Concrete ◽

Strength And Durability

The research project aimed to investigate the effect of palm kernel shell (PKS) on the mechanical strength and durability of foamed concrete at the level of 10% to 60%. The samples were designed and prepared having a dry density of 1600 kg/m3with a binder to filler ratio of 1:1.2. Hardened foamed concrete samples were subjected to air cured and tested at the age of 7, 14, 28, 56 and 90 days. Mechanical performance of the PKS foamed concrete was assessed in term of its compressive strength. Durability properties namely water absorption and vacuum porosity were investigated. The result shows that the addition of PKS to lightweight foamed concrete up to 30% significantly improve the mechanical properties and the durability of the foamed concrete.

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Mechanical performance of Scots pine wood from northwestern Poland – A case study

BioResources ◽

10.15376/biores.15.3.6781-6794 ◽

2020 ◽

Vol 15 (3) ◽

pp. 6781-6794

Author(s):

Edward Roszyk ◽

Przemysław Mania ◽

Elżbieta Iwańska ◽

Władysław Kusiak ◽

Magdalena Broda

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Scots Pine ◽

Mechanical Performance ◽

Raw Material ◽

Site Conditions ◽

Commercially Important ◽

Growing Conditions ◽

Northwestern Poland

Scots pine is one of the most commercially important wood species in Europe. This study assessed the potential usefulness of pinewood from the Noteć Forest for construction purposes by evaluating its mechanical properties and investigating the influence of the site conditions on the pinewood performance. Additionally, the variability of the mechanical properties from the bark to the pith was analyzed. The results showed that the properties of pinewood varied significantly within the Noteć Forest despite similar growing conditions, which may be a result of genetic variation. Wood from Sowia Góra had the greatest density (566 kg/m3) and excellent mechanical performance (compressive strength of 64 MPa), while wood from Zamyślin exhibited the lowest density (526 kg/m3) and a lower compressive strength (54 MPa). Comparison of the properties of the pinewoods from various locations indicated that the general conditions in the forest stand, however crucial for tree growth, were not the only determinants of wood performance. The results also showed high variability in density and mechanical properties between juvenile and mature wood in all the examined trees. Overall, pinewood from the poor habitats of the Noteć Forest could be a useful raw material for various industrial purposes.

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Characterisation of recycled ceramic mortars for use in prefabricated beam-filling pieces in structural floors

Materiales de Construcción ◽

10.3989/mc.2019.04518 ◽

2019 ◽

Vol 69 (334) ◽

pp. 189

Author(s):

P. Rubio de Hita ◽

F. Pérez-Gálvez ◽

M. J. Morales-Conde ◽

M. A. Pedreño-Rojas

Keyword(s):

Mechanical Properties ◽

Chemical Composition ◽

Partial Replacement ◽

X Ray Diffraction ◽

X Ray ◽

Ceramic Waste ◽

Physical Chemical ◽

Different Types ◽

Materials Used

This study analyses a procedure to manufacture mortars with different percentages of ceramic waste as partial replacement for aggregates. The study also examines the physical, chemical and mechanical properties of the new mortars, analysing substitution ratios that range from 10% to 50%. Prior to this, all the materials used in the production of the mortar were characterised using X-ray diffraction (XRD) and fluorescence (XRF). The objective was to determine the similarity between different types of ceramic waste, as well as the differences in the minerology and chemical composition with the aggregate. The results of the study show that it is possible to obtain mortars with lower densities compared to the same product with no recycled content. The product’s characteristics make it ideal for the manufacture of prefabricated components for structural floors for rehabilitation works. Finally, the pieces are used in a real rehabilitation case study, highlightining the structural advantages.

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