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The Magnetic Adaptive Testing (MAT) method emerges as a promising avenue for non-destructive inspection of steel-based materials, offering significant potential in measurement and metrology applications. Overview of the properties and utilization prospects of MAT in this domain is provided. The theoretical framework underlying the MAT method, elucidating its fundamental principles, and highlighting its suitability for precise assessments of ferromagnetic materials is described. The article discusses the new researched evaluation approaches, which include several filtering methods and the comparison of correlation coefficients, evaluating the relationship between the measured properties of the material before and after applying the load, with the aim of increasing the accuracy and universality of the method. Furthermore, it addresses the primary sources of uncertainties encountered in MAT measurements. [ABSTRACT FROM AUTHOR]

This paper focused on investigating the problems associated with the expansion joints in Al Murtadha Bridge that may cause significant damage to its structural components. In addition, the considerable expenses associated with the ongoing maintenance of these expansions were also taken into account. An examination was conducted to determine potential strategies for addressing these challenges, with structural analysis carried out using a CSI bridge software program according to AASHTO LRFD 2017. A potential solution was proposed to reduce issues related to expansion joints on bridges and enhance bridge durability, subsequently leading to an improvement in the service life of the bridges. A link slab was designed to connect the two adjacent spans instead of the expansion joint. Two options were suggested the first one uses Conventional Concrete CC in a link slab and the other uses Ultra High Performance Concrete UHPC as another one. [ABSTRACT FROM AUTHOR]

We all know that a flat slab is sort of slab in the structure don't possess beams. Straight from the slabs, the load is carried to the columns. To withstand shear, a long section of the slab known as the Drop is offered. In comparison to traditional slabs, a flat slab is more affordable. There is a tonne of preserved material. The goal of study is to present a cross-section of structural elements that can meet the stability requirements of IS standards. The primary goal of this effort is to identify the structural components that are cost-effective for G+10 structures in various seismic zones. With the help of the CSI ETABS 2018 software, the building models are examined. [ABSTRACT FROM AUTHOR]

Using local continuous fiber reinforcements in highly stressed component areas, the mechanical properties of injection molded structural parts can be significantly improved while maximizing the potential for lightweight design. The 3D skeleton winding process (3DSW) is a robot-based 3D filament winding approach which enables the winding of thermoplastic impregnated continuous fiber reinforcements, based on commingled yarns (CY), to complex skeleton-like fiber structures. These fiber skeletons (FS) can subsequently be embedded in the final component geometry as local continuous fiber reinforcements using conventional injection molding. The robot-based generation of FS in combination with injection molding means that this manufacturing process can also be applied in the production of highly optimized structural thermoplastic components in larger quantities. This paper presents how the characteristics of the PPS matrix used as thermoplastic filaments in the CY and as overmolding matrix affect the mechanical properties of glass fiber-reinforced tensile loop specimens. Furthermore, the general lightweight potential using wound continuous reinforcements in combination with polyphenylene sulfide (PPS) is demonstrated on a generic 3D structural component. [ABSTRACT FROM AUTHOR]

The competitiveness of present day engineering is based on the four most important criteria: quality, cost, level of service, and maintenance costs. Quality and price aspects are embedded at the design stage which determines the need for prioritising their planning in the initial stages. Assigning criteria must be based on the hierarchy principle which defines the interconnection and inter-subordination of the structural components of a technical system. When using such an approach, the technical requirements that determine consumer quality (desirable quality) of separate components of machinery products, determine in its turn the desirable quality of the materials of these components. This allows us to ascertain that planning the desirable quality for the material used for production of a specific machinery component must depend on the values of indicators and norms for the three complex properties of this material: its capability to perform its purpose, ease of manufacturing and safety. The choice of quality criteria for the material of structural components plays a special role in this case as they allow for planning the demanded properties for both the material and the technical system (machinery production) on the whole, as well as for varying the economic dimensions. [ABSTRACT FROM AUTHOR]

The aim of the research was a comparative analysis of the morphometric parameters of chicken eggs, characterizing their morphological and qualitative composition, as well as studying the dynamics of changes during the reproductive period. In age dynamics, the volume of the egg (10.1%), the area of the longitudinal section (9.1%), the large diameter (7.5%), the surface area (7.4%), the length of the larger circumference (5. 2%). The small diameter (1.3%), the length of the smaller circle (1.2%), and the cross-sectional area (2.5%) changed slightly. The egg shape index varied from 0.755 to 0.857 at 42 weeks of oviposition, and at 80 weeks from 0.684 to 0.844 units. With an increase in the mass of eggs, the value of the shape index significantly decreased by 6.4%. At the 42nd week of oviposition, the egg weight averaged 53.06 g, and at the 80th week, respectively, 59.03 g. The protein weight increased by 5.0%, the yolk by 23.2%, and the shell by 13.9%. With an increase in the absolute mass of the protein, its relative content in the egg decreased from 61.0% at the 42nd week of oviposition of the hens to 57.9% at the 80th week. The relative mass of the yolk increased from 25.9% to 26.7%, and that of the shell from 13.1% to 13.5%. A positive relationship was found between the weight and the size of the structural components of the egg, which varied from 0.17 (shell thickness) to 0.82 (protein weight). A positive correlation was found between the angle of the sharp end of the egg and the cross-sectional area (0.33), as well as the longitudinal section area (0.23). [ABSTRACT FROM AUTHOR]

Data-driven procedures are gaining importance in Structural Health Monitoring (SHM) because of current technical advances in sensors, as well as high-velocity internet and cloud-based processing. Machine Learning (ML) has gained substantial attention among researchers since its capability of handling huge continuous data. Damage identification utilizing vibration response is a dynamic space of exploration. In the present paper, Vibration responses are used for damage diagnosis. Modal responses of experimental and the numerical models of the cantilever beam are validated with analytical solutions. Different damage scenarios are generated and the modal responses are extracted for all the bending modes. Support Vector Machines, a Supervised Machine Learning algorithm is applied to predict the damage extent and the efficacy of the algorithm is evaluated by comparing the with the test data. [ABSTRACT FROM AUTHOR]

The harmony among the structural components plays a vital role in mitigating the effects of earthquakes. There must be a connection between the proportions of the load bearing components to guarantee this harmony. To prevent local collapse mechanism most of the seismic design codes over the world adopt strong-column weak-beam (SCWB) design i.e., the moment capacity of the columns should be greater than the beam moment capacity, to ensure the beams fail first. In this paper, Non-Linear Static analyses are conducted for Reinforced Concrete special moment-resisting frame buildings. Building non-conforming and conforming to the strong-column weak-beam design criterion are considered. These buildings are designed for seismic zone V and medium soil following the codal provisions of Indian Standards. The effect of height of the building on the SCWB criterion is investigated. The results obtained shows that there is an increase in the Base Shear capacities and displacements when SCWB design is adopted. [ABSTRACT FROM AUTHOR]

The seismic performance assessment of existing buildings and constructions is often required to be conceived and tailored on the structure characteristics and behavior, which are exhibited in the static and dynamic environments. Quasi-brittle existing constructions or structural and non-structural components present in existing structures, which exhibit an heterogeneous resistance, are usually requiring and pushing towards the formulation and adoption of suitable mechanical models able to capture the non-linear nature of their behaviour. Current modelling issues for masonry constructions and components are usually relying on mechanical models of basic materials, where the tensile resistance is almost completely, or completely, neglected. In the paper the problem of interactions and coupling of elements exhibiting a non-linear behaviour and non-heterogeneous resistance with linear elastic structural components is investigated also with reference to the evaluation of the overall lateral resistance of mixed elements, with the task of deepening the incidence of this feature on the structural resistance to horizontal loads and on the decay of the seismic performance of the structure. [ABSTRACT FROM AUTHOR]

This paper describes a method of determining the reliability of a hardware-software complex for real-time systems at the design stage. Reliability is one of the main aspects of hardware-software real-time information processing systems. To increase hardware reliability, it is necessary to use the redundancy of structural components such as processors and interface buses. Software reliability increases through multiversion programming. As a result, a model for calculating the reliability of a multiprocessor hardware-software real-time system with heterogeneous processors and multiversion software had been obtained. The model allows to study variety of architectures for a short period of time without significant costs typical for building prototypes and assessing reliability through trial. In the conclusion, the question about possibility of optimizing a hardware-software complex reliability based on the model is raised. Also, the methods of optimization which can be used to solve this problem are specified. [ABSTRACT FROM AUTHOR]

It is well known that woodpeckers and their distribution is mostly affected by deadwood. However, in Latvia there have not been any studies about how other forest structural components like growing trees and vegetation can affect distribution of woodpeckers and their choice of habitats. In recent years estimation of ecosystem services has become popular in Latvia and it is used in nature conservation matters. The aim of the research was to analyse structures characterizing the habitats of broadleaf forests and identify for which woodpecker species broad-leaf forests are suitable habitat. An assessment of ecosystem services has also been applied to determine value of woodpeckers and their habitats. The amount of dead wood in the habitat is on average 71.2 m³ ha-1, of which majority or 87% is made by logs, while the smaller par tor 13% - by snags. It is possible to determine suitability of the habitat for various woodpecker species by analysing different structures that characterizes habitats - they are suitable for almost all species of woodpeckers. The study also shows that residents of Jelgava municipality would be willing to pay 11.00 EUR a year from a person to protect woodpecker species and to conserve their habitats. [ABSTRACT FROM AUTHOR]

This paper presents the compressive strength of zeolite-based geopolymer paste produced with various alkali to zeolite (A/Z) ratio of 0.4-0.7; and curing temperature (60°C and 80°C for 24 h) with sodium hydroxide (Na0H) molarity of 8 M. Specimens were tested for compressive strength after 28 days in ambient temperature. The test results showed that A/Z and curing temperature significantly influenced the compressive strength values. The optimum compressive strength was achieved with A/Z ratio of 0.5 and cured at 60° which is about 18.34 MPa. The zeolite-based geopolymer paste prepare in this study can be used for structural components from compressive strength viewpoint. [ABSTRACT FROM AUTHOR]

Assumptions and simplifications in finite element (FE) modelling for structural vibration analysis contribute to discrepancies in numerical results. This paper presents FE model updating on components of a simplified model of an aircraft pylon. The components are tested under free-free boundary conditions. Impact testing is performed with roving accelerometers technique. Modal parameters are predicted numerically using NASTRAN SOL 103 normal modes analysis. NASTRAN SOL 200 optimisation for modal based updating method is subsequently used and successfully minimised the total error of the initial FE model from 19.17 per cent to 3.19 per cent. These satisfactory results could be confidently enhanced the quality of the FE model to be used for the further engineering analysis. [ABSTRACT FROM AUTHOR]

Functionally graded materials (FGM) with their superior mechanical properties are widely used in transport engineering (for instance, in aeronautics). The safety and reliability of functionally graded structural members and components depend in a high degree on their fracture behavior. This paper describes a longitudinal fracture analysis of a statically undetermined functionally graded beam structure loaded in torsion. The beam has a circular cross-section. There is a longitudinal crack in the beam. The crack represents a circular cylindrical surface. The beam is under linear creep. The time-dependent energy release rate (ERR) for the longitudinal crack is analyzed by considering the energy balance. Verification is performed by analyzing the compliance. A parametric investigation of the time-dependent ERR is carried-out. [ABSTRACT FROM AUTHOR]

The properties of the basic materials of conveyor belts and adhesion between these materials affect the proper functionality and service life of conveyor belts. Their reliability depends on the adhesive force between their structural components. The purpose of this paper was to investigate into the quality of adhesion of the rubber cover layers to the carcass, and of the adhesion between the adjacent textile plies in a rubbertextile conveyor belt. The experiments were aimed at measuring the adhesive force using the tensile testing machine with a constant rate of traverse. The investigation was carried out with 4 conveyor belts with carcasses made of the same material. The experiments were carried out in compliance with the recommendations of the ISO 252:2007 standard and the results were verified according to the ISO 14890:2013 standard. The strength of adhesion between textile plies of the carcass and rubber is very important in the both production and applications of rubber-textile conveyor belts. [ABSTRACT FROM AUTHOR]

The aim of this work was to create a complex three-dimensional model of the VVER-400 / V-213 reactor, i.e., V-2 NPP, and the surrounding area using the MCNP code to perform a calculation of the induced activity of structural components with respect to the planned 60-year period of operation. The survey of operational history defined a reference campaign on the basis of which a neutron source term was developed, which took into account parameters such as height distribution of fuel and control assembly burnup, change in fuel density depending on burnup, moderator temperature distribution and moderator density change from temperature, boric acid concentration in the moderator and position of the 6th group of control assemblies. A model of the V2 NPP reactor was created at the core level. The calculation of the induced activity was performed using the code MCNP5 with cross-section library ENDF / B-VII.1. In addition to the methods and model used in this analysis, the paper also summarizes the results that can be generally applied to the mentioned type of nuclear power plant. At the time of shutdown, the total activity of the steel components reached the level of 7.14E + 09 Bq/g. Reactor biological shielding concrete reached the level of 1E + 07 Bq/g. [ABSTRACT FROM AUTHOR]

Al7050 is distinct among the Al – 7xxx alloy series due to its remarkable features. The rudimentary properties of Al7050 can be improved with the addition of appropriate reinforcing materials to further increase in its adaptability as various structural components. Extensive research is being carried out using different forms (metallic, non-metallic and organic compounds) of reinforcing materials to obtain suitable Aluminium metal matrix composites (AMMC) for specific applications. This review aims to provide an overview of two different reinforcement materials viz., Graphene and Silica utilized in Al7050 MMC and elaborates on the change in characteristics of the composite due to reinforcement inclusion. [ABSTRACT FROM AUTHOR]

Due to the widespread utilization of composites in structural and machine components, the dynamic analysis of these structures has become very essential for their efficient design. The present work deals with the investigation of the effect of fiber orientation/ lamination scheme on the non-linear forced vibration response of angle-ply laminated composite cylindrical shell. The finite element formulation has been carried out and the geometric nonlinearity has been incorporated. The formulation is based on the kinematics of FSDT and the governing equations have been obtained using Hamilton's principal. The solution procedure employed in the analysis is based on the modified shooting method. The nonlinear steady state frequency response curves have been obtained for different lamination scheme. The differences in the response characteristics for different fiber-angle have been explained through the distribution of strain/stress across the thickness of the laminate. The cyclic variation of the response, its FFT and the phase plane plots are also obtained to explain the nature of the non-linear response. [ABSTRACT FROM AUTHOR]

Using the generalized self-consistent field method, the competing effect of structural components on the effective characteristics for problems in terms of generalized conductivity (on the example of heat conductivity) is considered. To this end, the problem of determining the effective characteristics of the system under consideration with the use of the generalized self-consistent field method is preliminarily solved in this paper. To find the effective characteristics of the system under consideration, a comparison body is introduced, representing a malfunctioning homogeneous medium. Each phase component is considered separately in an infinite matrix possessing the properties of a comparison body. In this case, the field in a single inclusion is identical to the mean field in the volume occupied by this phase in a heterogeneous material. In addition, using the Fourier law, which connects the average values of macroscopic fields through the effective coefficient of thermal conductivity and the additivity condition for the average value of the heat flux in the composite material. Expressions for effective characteristics contain a variable parameter that allows us to consider systems with different topologies. [ABSTRACT FROM AUTHOR]

A computational quasi-static model is proposed to simulate fracture in materials and along material interfaces. In any case, the cracks are modelled within the mechanical damage theory introducing two independent damage variables: one for domain damage, one for interface damage. The interface cracks are supposed to appear in a negligibly thin adhesive layer of an interface between two structural components so that cohesive zone models with generally prescribed stress-strain relationships can be implemented within a variationally based model. Similarly, the fracture in the material also considers an energy state and results in phase-field damage which brings about bulk degradation only in a narrow material strip forming the actual crack. The computational approach for finding an approximation of such a variational formulation includes a time stepping procedure with the solution at each instant being obtained by sequential quadratic programming algorithms implemented together with a finite element code. [ABSTRACT FROM AUTHOR]

Coatings are multifaceted having raw materials combined and utilized to a prepared substrate by allowing it to be dried and cured to obtain effectiveness. Majority of coating challenges occurs in coating manufacturing and its application in different environment not shielded away from the impact of rain, sunlight, wind, heat, cold, humidity, and oxygen. Few coatings, including those applied in marine, aerospace, automobile and medical cannot resist some difficulties arising from corrosion. This paper focuses on identifying the challenges in marine, aerospace and automobile. In marine, the antifouling coating at the watertight body of the ship destroy organisms before they get close to it. Tributyltin (TBT), which is released to the ocean or the sea happens to be the most effective compound used for antifouling coating but its pose serious problems to marine organism due to its toxic substance.In automobile, application of chromium coating is the main source of exposure for workers leading to sneezing, headache, skin irritation, ulcers and respiratory disorder because of its ions that comes in contact with the environment in form of chromate and dichromate anions from the sewage while in aerospace ,movements of a aircraft structural joint would deform, elongate the coating system making the structural component of the aircraft coating system a major challenge in determining aircraft joint displacement. The essence of identifying coatings challenges is to find measure of ensuring substrate are improve in terms of ;appearance, bonding, moisture ability, resistance to wear etc. Hard chromium coated constituents can now find application in agricultural equipment's, aircraft industry, automobile, marine and other industries. [ABSTRACT FROM AUTHOR]

The usage of industrial manipulators is increasing globally due to its superiority. A topology optimization approach is a promising method to optimize the structural components of a robot to make energy-efficient. Topology optimization distributes the material in the design space based on solid isotropic material with a penalization approach. The ABB IRB-120 multi-body industrial manipulator is chosen here for dynamic analysis at maximum reach conditions. The upper arm of the manipulator is subjected to the topology optimization problem because it plays a vital role in dynamic performance. The one end of a manipulator is submitted to a fixed support, and another end experiences the forces and torque. Required constraints can be calculated employing multi-body dynamics simulations using ADAMS software. The objective function of the optimization chosen as the best stiffness to weight ratio for volume fraction values ranging from 0.2 to 0.7. The static analysis and topology study are simulated and analyzed using SOLIDWORKS software for given constraints and boundary conditions. The simulation results, such as deformation, and Von-Mises stress for optimized links at different volume fractions are compared with the initial design. [ABSTRACT FROM AUTHOR]

The study of the spectrum and structure of excited nucleon states employing the electroproduction of exclusive reactions is an important avenue for exploring the nature of the non-perturbative strong interaction. The CLAS detector in Hall B has provided the dominant part of the available world data on most relevant meson electroproduction channels off the nucleon in the resonance region for Q2 up to 5 GeV2. Analyses of CLAS data for the exclusive channels πN, ηN, and π+π−p on a proton target have provided the only results available on the Q2 evolution of the electro-excitation amplitudes for the transitions from the initial photon-proton to the final N* states in the mass range up to W =1.8 GeV. These electrocouplings allow for exploration of the internal structure of the produced excited nucleon states. This work has made it clear that consistent results from independent analyses of several exclusive channels with different resonance hadronic decay parameters and non-resonant backgrounds but the same N* electro-excitation amplitudes, is essential to have confidence in the extracted results. Starting in early 2018, a program to study the spectrum and structure of N* states in various exclusive electroproduction channels using the new CLAS12 spectrometer commenced. These studies will probe the structure of N* states in the mass range up to W =3 GeV and for Q2 as low as 0.05 GeV2 and as high as 10-12 GeV2, thus providing a means to access N* structure information spanning a broad range of distance scales. Quasi-real photoproduction studies are also planned to search for additional N* states, the so-called hybrid baryons, for which the glue serves as an active structural component. In this talk the N* programs from both CLAS and CLAS12 will be reviewed. [ABSTRACT FROM AUTHOR]

This work describes the methodology and the main results of the calculation of resonant wavelengths and absorption frequencies of microwave radiation for the main structural components of liquid water in the temperature range of 293…353 K. [ABSTRACT FROM AUTHOR]

It is shown that samples of crude oil produced from various objects of the Permian-Carboniferous deposit of the Usinskoye oil field and residual oils extracted from cores differ in their component and structural group composition. In the composition of the residual oil extracted from cores, the proportion of paraffin-naphthenic hydrocarbons is lower (by 14–25%) than that in the produced oil. It is found out the rate of asphaltene precipitation for extracted oils are significantly lower than that for residual oils. [ABSTRACT FROM AUTHOR]

Wet compression molding (WCM) provides large-scale production potential for continuously fiber-reinforced structural components due to simultaneous infiltration and draping during molding (viscous draping). Experimental and theoretical investigations proved strong mutual dependencies between resin progression and textile draping. Significant cavity pressures only develop towards the end of the tool stroke, when the cavity is almost filled with resin and fibers. Therefore, the resin’s impact on the draping behavior (intra-ply and interface behavior) is of great relevance, since it represents a large share of the draping process. This study extends the work presented by Hüttl et al. [1] with experimental interface tests on dry and infiltrated woven fabrics, which confirm rate-, pressure- and viscosity-dependent tangential contact behavior within the viscous draping stage. Furthermore, experimental results for the ply-ply interface are utilized to parametrizes a contact model, which is subsequently applied to assess and evaluate the process relevance on part level by means of FE forming simulation. Although a relatively simple geometry has been investigated, numerical results show a significant impact of the infiltration-depended tangential contact formulation on part level. Beyond that, an investigation of the ply-ply contact state (pressure or tension) reveal that transversal pressure is only predominate towards the end of the tool stroke. Consequently, contact characterization and parametrization should also include tests at low transversal pressure. [ABSTRACT FROM AUTHOR]

The structure and mechanical properties complex of X80 pipe grade steel after controlled rolling and low-temperature treatment were studied. The microstructure of X80 pipe steel has been studied, the size of the structural components has been determined. The mechanical properties of steel for samples cut perpendicular and parallel to the direction of the rolling axis are determined. Serial curves of impact toughness were constructed and the fracture surfaces of the samples of the steel under investigation were researched. [ABSTRACT FROM AUTHOR]

Determination of mechanical properties in multiphase bodies of extraterrestrial origin is a fundamental task. In this work the hardness and Young's modulus in the Seymchan pallasite were determined in kamacite a-Fe (Ni, Co), taenite α-Fe (Ni, Co), plessite (α+γ), tetrataenite FeNi using nanoindentation technique. For the first time, the hardness and modulus of elasticity of a two-phase nanostructure of cloudy zone FeNi+a-Fe(Ni,Co), formed as a result of very slow cooling (about 1 K/Myr), was determined. [ABSTRACT FROM AUTHOR]

The term smart growth is defined as developing an economy based on knowledge and innovations (EC, 2010). According to Eurostat (Eurostat regional yearbook 2014, Eurostat yearbook 2018, etc.), an expansion of the knowledge-based economy segment is observed in the European Union, which leads to a structural redeployment of the economy. Accordingly, growth in the knowledge-based economy segment becomes an important research problem in each EU Member State. The authors analysed this process in three Baltic States, placing a special focus on Latvia, which is represented by the authors. Based on data of the World Economic Forum, Eurostat, the Latvian Business Register (LURSOFT) and the Central Statistical Bureau (CSB) of Latvia, the authors assessed the expansion of the knowledge-based economy segment and its structural components due to globalisation. A structural redeployment, first, in the economy as a whole, second, in the knowledge-based economy segment as a whole and, third, in each of the knowledge-based economy sub-segments has been observed in Latvia. The research results allow concluding that bioeconomy- and digitalisationrelated economic activities grew at the highest rates in the knowledge economy of Latvia. Consequently, opportunities for Latvia to become a strong innovator increase, and through contributing to smart growth, sustainable and inclusive growth is promoted as well. [ABSTRACT FROM AUTHOR]

The objectives of the study were to develop approaches to evaluate the effectiveness of the institutional matrix of regional innovation systems from the point of view of the formation of “key” institutions for sustainable development, identification of the structural components of the “green” innovation system, their resources and functions. The methodological basis of the study was an interdisciplinary approach, including a comparative analysis of foreign and domestic scientific discourse on “green” innovation, as well as analysis of reports and studies on various aspects of the development of “green” economy and “green” innovations, case analysis, statistical data analysis, system analysis based on quantitative and qualitative approaches. The authors found that the differentiation of organizational structures of intersectoral interaction, their resource potential and functionality in the field of creation and promotion of environmental innovations determines the poly-variable nature of institutional design practices, as well as their results. The authors established possible risks of institutional development of innovation systems associated with the ongoing shift of the scientific and technological structure and social changes. Based on an empirical study of institutional practices in Russian regions, the authors identified and analyzed the main institutional mechanisms and tools that determine the success of the “scenarios” of the institutional development of eco-oriented innovation systems. It was justified the need to develop analytical tools with a set of interrelated indicators in order to adequately assess the effects of the dynamics of the regional innovation system in the context of national and global socio-economic processes. A structural model of a regional ecoinnovation system has been developed. [ABSTRACT FROM AUTHOR]

Grouted ground anchor is a structural component used to transmit tension force from the structure to the subgrade. Determination of the ground anchors ultimate carrying capacity is mostly conducted using various empirical and semi-empirical methods. These procedures are usually successful, but highly simplified. Hence, each system ground anchor has to be tested during its prestressing to prove design assumptions. The aim of the test is to prove accomplishment of acceptance criteria, which has been defined to demonstrate the capacity and serviceability of tested anchor. The acceptance criteria are derived also from the investigation tests conducted in advance on non-system anchors. The research project aimed on the better understanding of behavior of prestressed ground anchors in fine-grained soils has been solved in Czech Republic. One of the outputs of this research is the software utility developed for purpose of keeping and evaluating the test records according to the new Europe recommendations. The paper describes set up of full-scale investigation test of ground anchors and the process of evaluation the results of such test via newly developed software. [ABSTRACT FROM AUTHOR]

The article analyzes methodological approaches to defining the concept of "adaptive capacity of an individual". The content of this phenomenon as well as the structural components of the adaptive capacity of adolescents are being discussed. [ABSTRACT FROM AUTHOR]

Spring up trends and necessities make the pipelines for the brand new Technologies. The same way, Multimaterial structures emerging as fruitful alternatives for the conventional structures in the manufacturing sector. Especially manufacturing of transport vehicles is placing a perfect platform for these new structures. Bonding or joining technology plays a crucial role in the field of manufacturing for sustainability. These latest structures are purely depending on such joining technologies so that multi-material structuring can be possible practically. The real challenge lies on joining dissimilar materials of different properties and nature. Escalation of thermoplastic usage in large structural components also faces similar ambiguity for joining multi-material structures. Adhesive bonding, mechanical fastening and are the answering technologies for multi-material structures. This current paper analysis the prospects of these bonding technologies to meet the challenges of tomorrow. [ABSTRACT FROM AUTHOR]

Due the presence of through-thickness reinforcement which eliminates delamination, 3D woven composites have superior fracture toughness, fatigue life, and damage tolerance compared to laminated composites. Unlike 2D laminated composites which exhibit catastrophic failure typically through delamination, 3D woven composites exhibit a progressive damage behavior that leads to high specific energy absorption (SEA). Thus, enabling the manufacture of reduced weight structural components for energy absorption compared to traditional materials such as laminated composites or high strength metals. This is of particular importance for automotive applications, where weight reduction is sought through material change in vehicle components that play a critical role in crashworthiness. The rate dependent nature of these materials, however, is not well understood. The goal of this study was to experimentally compare the SEA of various 3D woven and 2D laminated composites manufactured with identical carbon fiber and resin that were tested under quasi-static and various dynamic crushing loads. In general, 3D woven composites were found to have higher SEA measures than 2D laminates, and orthogonal fiber topologies were found to have higher values than ply-to-ply interlocking configurations. All specimens tested displayed substantially reduced SEA for higher velocity impacts. Microcomputed tomography scans of tested samples were used to gain insight into energy absorption mechanisms in 3D woven composites. Finally, resin toughening was found to have a significant impact on SEA performance. [ABSTRACT FROM AUTHOR]

High performance composite-to-metal joints require reliable manufacturing process to produce repeatable adhesive bond quality. Contamination on pre-bond surfaces stands as a major threat to adhesive bonded structural components. Growing capability in detecting and removing contaminants on pre-bond surfaces has been a strong driving force over years in adhesive bonding applications. In this study, contaminants from multiple sources, including mold release, lubricant and shop environment, were introduced to the pre-bond surfaces. Plasma and laser surface treatments were applied and their effectiveness in removing contaminants was investigated. Surface tension measurement by water contact angle and elemental analysis of surface functionalities by X-ray photoelectron spectroscopy were performed to reveal fundamental surface characteristics and modifications induced by plasma and laser surface treatments. A hybrid composite-to-metal sample configuration was developed for double cantilever beam test. Fracture toughness and associated failure modes were assessed before and after surface treatments. Both plasma and laser surface treatments demonstrated great potentials in enhancing bond performance and removing contaminants. [ABSTRACT FROM AUTHOR]

The multi material design (MMD) enables the use of locally optimized materials with required properties and low costs. A vital challenge of the MMD is the demand for suitable technologies for joining different types of materials like metal and fibre reinforced thermoplastics (FRP) concerning the performance and large-scale production. Novel lightweight-optimized hybrid metal- FRP structures contain locally reinforced joining areas. A suitable process for high-volume production with regard to sustainability and recyclability is the thermoforming process for fibre reinforced thermoplastics. The base material is a planar FRP organic sheet. If both - metal structures and FRP reinforcements - have to be integrated locally into the FRP part, this requires a modified thermoforming process, which ensures the forming from planar to 3D and a proper joining between the FRP/FRP and FRP/metal interface during consolidation. Different approaches are evaluated in this paper: a multi-step process with separated forming of metal and FRP plus final consolidation, a novel customized process with integral forming and consolidation of all parts in a single step as well as a mixture of both. [ABSTRACT FROM AUTHOR]

Carbon fibre reinforced polymer (CFRP) composites employing epoxy matrices have been recently used in a number of space applications, especially in structural components of spacecraft in low Earth orbit (LEO). However, in this region, CFRP structures are subjected to degradation by highly energetic ultraviolet radiation. Aromatic epoxies, which are commonly used, contain rigid phenyl rings, which confer higher mechanical properties and thermal stability, but these structural moieties absorb UV radiation strongly. In contrast, fully saturated cycloaliphatic epoxy resins are better suited for outdoor exposures, since they are poor chromophores with lower intensity UV absorption. In this work, we report on incorporation of an octa-functional polyhedral oligomeric silsesquioxane (POSS) reagent into a cycloaliphatic epoxy and discuss the influence of this hybridization on the thermal-degradation mechanism. POSS has been added in various concentrations of 5, 10, 15 and 20 wt. % and the cycloaliphatic epoxy was cured with either an anhydride or a cycloaliphatic diamine. The thermal and thermomechanical properties of each cured polymer were evaluated using thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). The findings of this study contribute to development of advanced polymer matrix materials for extreme operation environments, such as LEO. [ABSTRACT FROM AUTHOR]

Hot stamping constitutes a manufacturing process for both high strength and lightweight automotive structural components and is used to produce some 40 % of today's structural components in car bodies. Lightweight approaches aim at weight reduction by reducing steel thickness and applying fiber-reinforced plastics (FRP) to regain structural stiffness and strength. Inherent thermal metal processing renders hot stamping an adequate process chain for the manufacturing of hybrid metal polymer composites. Thereby, residual heat in metal parts is used to enhance adhesion between polymer and metal. In fact, the temperature of the parts after hot stamping is in the range of the processing temperatures of several technical polymers, thus providing process conditions suitable for thermal direct joining or activation of adhesion promoters. In this paper, the integration of fusion bonding of thermoplastic FRP in the hot stamping process chain is investigated. Therefore, characteristic process requirements are matched with actual temperature behavior and thus, hybrid specimens are manufactured under realistic industrial conditions. The specimens are tested with respect to shear strength and bending stiffness, resulting in adequate mechanical performance at reduced mass. [ABSTRACT FROM AUTHOR]

Using the generalized self–consistent field method, the competing effect of structural components on the effective characteristics for problems in terms of generalized conductivity (on the example of heat conductivity) is considered. To this end, the problem of determining the effective characteristics of the system under consideration with the use of the generalized self–consistent field method is preliminarily solved in this paper. To find the effective characteristics of the system under consideration, a comparison body is introduced, representing a malfunctioning homogeneous medium. Each phase component is considered separately in an infinite matrix possessing the properties of a comparison body. In this case, the field in a single inclusion is identical to the mean field in the volume occupied by this phase in a heterogeneous material. In addition, using the Fourier law connects the average values of macroscopic fields through the effective coefficient of thermal conductivity and the additivity condition for the average value of the heat flux in the composite material. Expressions for effective characteristics contain a variable parameter that allows us to consider systems with different topologies. [ABSTRACT FROM AUTHOR]

In this paper, the theoretical and experimental results of fatigue crack growth in AISI 5140 steel have been presented. According to the previous theoretical background - the energy parameter ΔH is introduced as a crack driving force in construction of fatigue crack growth rate (FCGR) diagrams. The physical explanation of this model is also presented. In experimental parts of this work, the kinetics fatigue fracture diagrams (KFFD) for AISI 5140 steel were constructed. The main goal of experimental works was to investigate the influence of microstructure on kinetics of fatigue crack growth. The AISI 5140 steel were tested in three different heat treatment conditions. As it has been confirmed, the energy parameter H describes the kinetics of fatigue crack growth much more synonymously than the classical stress intensity factor - ΔK. [ABSTRACT FROM AUTHOR]

Newly developed freeform architecture offers great potential. But it also sets strong demands on design and manufacturing technologies. New developments in the fields of CAD and CAM open new possibilities. Therefore, both new production methods and new planning tools are necessary to manufacture these architectural forms properly and more efficient. The Collaborative Research Center 666 (CRC 666) explores different methods of cold forming of sheet metal. In particular, flow splitting and bend splitting both result in an ultrafine grain structure of the metal and thus a material hardening. These profiles can be manufactured with defined curvature radii. In subsequent processing steps cut-outs can be milled. These technologies are offering the possibility to use sheet metal material for structural elements of freeform shells or skins because of their precise shaping options. To apply these new manufacturing technologies to highly individualized structures, the production processes needs to be considered at an early stage in the design phase of a building. Especially for the form finding and the subdivision into producible elements new geometric methods are needed. Therefore this paper shows an approximation method for the simplification of free geometries into single curved strips. [ABSTRACT FROM AUTHOR]

The use of industrially prefabricated components is gaining an increasing importance in the construction industry. The on-site assembly of finished components requires very high standards on their joining techniques. The currently explored technology of the Collaborative Research Centre 666 "Integral Sheet Metal Design with Higher Order Bifurcations - Development, Production, Evaluation" (CRC 666) has great potential to develop new and innovative joining techniques. With these new connection new product lines can be developed. Thereby the new cold forming processes of linear flow splitting and linear bend splitting are producing integral bifurcations. These techniques have improved material properties due to an ultra-fine grained (UFG) structure in the new shaped flange. Based on selected conventional joining techniques new joining techniques were developed. Then these representative selected joining techniques are assessed qualitatively in terms of previously defined evaluation criteria. After comparing the conventionally and newly developed joining techniques, the favored solutions were discussed critically and constructive recommendations were drafted. [ABSTRACT FROM AUTHOR]

Structural components unavoidably are affected by defects such as surface scratches, surface roughness and weld defects of random sizes, which usually occur during the manufacturing and handling process. These defects are shown to have an important effect on the fatigue life of the structural components by promoting crack initiation sites. In general, the fatigue and fracture performance of cracks contains a significant number of uncertainties. Fatigue phenomena have a deep stochastic behavior that must be taken into account. Equivalent initial flaws size(EIFS) has been developed as useful design tools to make life predictions for structural reliability problems. For probabilistic fatigue assessment by using EIFS in this study, the LEFM-based fatigue reliability approach is used based on a limit state function related to crack size and a damage accumulation function. From analysis results, the probabilistic reliability method can provide lifetime fatigue performance in terms of reliability and number of cycles, based on LEFM. This is useful for estimating both the cumulative number of cycles and remaining fatigue life. [ABSTRACT FROM AUTHOR]

Automated manufacturing of dry preforms for composite structures has shown to improve control and repeatability of fiber orientation as well as to increase process speed. This paper proposes an integrated braiding solution for curved centerline mandrels with axisymmetric sections. It combines the flexibility of a seven degrees of freedom industrial manipulator with a 144 carriers radial braiding machine. The mandrel is braided by keeping its centerline coincident with braider's central axis, ensuring constant radial tension of yarns along the process. Pre-processing starts by defining mandrel's centerline using Frenet-Serret frames. Du et al. braiding model is used to relate the braid's architecture with the mandrel's take-up speed. The convergence zone length is synchronized with the mandrel's positions in order to diminish the transitory regime. Based on the centerline definition and take-up speeds, a multi-objective algorithm optimizes the path of the manipulator. The braiding solution's repeatability, accuracy and precision were validated on an industrial system. Two mandrels with increasing complexity were braided. Fiber angles were measured by imaging. A statistical analysis done on the measured fiber angles confirms the predictions made using the integrated braiding solution. [ABSTRACT FROM AUTHOR]

The current study uses FRP structural components for the design of a green fence, and performs a three-point bending test of the FRP profile specified by the design in an effort to determine the FRP profile ultimate flexural strength. Moreover, connection pull-out tests of mechanical connection and chemically bonded connection were separately performed as well as FRP beam-column connection strength test. It is expected that the viability of FRP green fence can by testified from the ultimate loads obtained from both experiments. A demonstration case study was also performed to prove the feasibility of the FRP green fence. In the end, a carbon footprint evaluation and life cycle cost assessment are conducted to evidence the low carbon emission and low life-cycle cost of FRP green fence. [ABSTRACT FROM AUTHOR]

In the present work a numerical investigation on the energy absorbing capability of dedicated structural components made of a carbon fiber reinforced polymer and an emulsion polymerised styrene butadiene rubber is reported. The shock absorbers are devices designed to absorb large amounts of energy by sacrificing their own structural integrity. Their aim is to cushion the effects of an impact phenomenon with the intent to preserve other structures from global failure or local damaging. Another important role of shock absorbers is reducing the peak of the acceleration showed during an impact phenomenon. This effect is of considerable interest in the case of vehicles to preserve passengers' safety. Static and dynamic numerical results are compared with experimental ones in terms of mean crushing forces, energy and peak crushing. The global performance of the absorbers has been evaluated by referencing to a proposed quality index. [ABSTRACT FROM AUTHOR]

Investigations on PP-LGF30 foam sandwiches have been carried out using different manufacturing processes: standard injection molding, MuCell® and LFT-D foam. Both chemical and physical blowing agents were applied. Precision mold opening (breathing mold technology) was selected for the foaming process. The integral foam design, which can be conceived as a sandwich structure, helps to save material in the neutral axis area and maintains a distance between load-bearing, unfoamed skin layers. The experiments showed that, at a constant mass per unit area, integral foams have a significantly higher flexural rigidity than compact components, due to their greater area moment of inertia after foaming: with an increase of the wall thickness from 3.6 mm to 4.4 mm compared to compact construction, the flexural rigidity increased by 75 %. With a final wall thickness of 5.8 mm an increase of 300 % was measured. Compared to non-reinforced components that show significant embrittlement during foaming, the energy absorption capacity (impact strength) of LFT foam components remains almost constant. [ABSTRACT FROM AUTHOR]

Predictive health monitoring of structural components will require the development of advanced sensing techniques capable of providing quantitative information on the damage state of structural materials. By focusing on nonlinear acoustic techniques, it is possible to measure absolute, strength based material parameters that can then be coupled with uncertainty models to enable accurate and quantitative life prediction. Starting at the material level, this review will present current research that involves a combination of sensing techniques and physics-based models to characterize damage in metallic materials. In metals, these nonlinear ultrasonic measurements can sense material state, before the formation of micro- and macro-cracks. Typically, cracks of a measurable size appear quite late in a component's total life, while the material's integrity in terms of toughness and strength gradually decreases due to the microplasticity (dislocations) and associated change in the material's microstructure. This review focuses on second harmonic generation techniques. Since these nonlinear acoustic techniques are acoustic wave based, component interrogation can be performed with bulk, surface and guided waves using the same underlying material physics; these nonlinear ultrasonic techniques provide results which are independent of the wave type used. Recent physics-based models consider the evolution of damage due to dislocations, slip bands, interstitials, and precipitates in the lattice structure, which can lead to localized damage. [ABSTRACT FROM AUTHOR]