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A frequently overlooked aspect in previous research on bearing capacity of reinforced foundations is the prevalent unsaturated properties of soils. This paper provides an analytical framework for evaluating the bearing capacity of strip footings with single-layer and double-layer reinforcement in unsaturated soils. Four classical nonlinear expressions are used to determine the additional cohesion induced by matric suction. Solutions for the reinforcement layer undergoing tensile failure and sliding failure are provided separately. In the former case, where the bearing capacity depends on the reinforcement's tensile strength, the Prandtl mechanism is employed. In the latter case, where the bearing capacity is influenced by the characteristics of the reinforcement-soil interface, a multi-block mechanism is adopted. Additionally, sliding failure exhibits different mechanisms depending on the reinforcement's embedded depth. By comparing the results of different failure mechanisms, accurate upper bound solutions for bearing capacity are obtained. In the case of sliding failure, the optimal reinforcement depths that maximize the bearing capacity are identified for both single-layer and double-layer reinforcement. To facilitate engineering use, the optimum depths and corresponding bearing capacity factors are given in tabular form. The effectiveness of the framework is demonstrated through comparisons with previous theories, experiments, and finite element simulation results. • Utilizes four kinds of nonlinear expressions to quantify the effects of matric suction on additional cohesion and integrates these into the Terzaghi formula. • Provides a quantitative analysis of the impact of sliding and tensile failures of single and double-layer reinforcements by incorporating calculations of reinforcement energy dissipation. • Presents two methods for evaluating the bearing capacity of reinforced foundations in unsaturated soils, with optimal reinforcement depth positions and corresponding bearing capacity factors recorded in tabular form. [ABSTRACT FROM AUTHOR]

The unlubricated sliding-wear behaviour of WC cemented carbides fabricated by pressureless infiltration of the Cu–30Mn–1P alloy without and with Ni infiltration aids (in the range of 3–10 wt%) was investigated. Firstly, detailed microstructural characterisation showed that these cemented carbides are all dense and consist of extra coarse WC grains (∼62 μm) embedded into Cu 0.96 Mn 0.04 (with traces of P), plus secondary Mn 2 P and Mn 3 P phases segregated at the grain/binder interfaces. When infiltrated with Ni aids, the binder contains Ni solutes and there is also interfacial segregation of NiP 2 and Mn 3 Ni 20 P 6. Secondly, the mechanical characterisation showed that the Ni infiltration aids resulted in stronger and more ductile cemented carbides, with no reduction in hardness below 5 wt% Ni aids. Specifically, it was found that 3 wt% Ni infiltration is optimal, which maximises the strength, ductility, and toughness of these cemented carbides as a consequence of the optimised cohesion of the WC grains in the metal binder. And thirdly, the tribological characterisation against Al 2 O 3 showed that all these cemented carbides are wear-resistant, with specific wear rates increasing with applied load, but in the order of 10−5 mm3/(N·m) or lower. Importantly, it was found that Ni infiltration aids up to 5 wt% are beneficial to the wear resistance of these cemented carbides, but more becomes increasingly detrimental. As for the other mechanical properties, Ni infiltration at 3 wt% also maximised the wear resistance. Detailed microstructural characterisation of the worn surfaces of the cemented carbides revealed that wear took place first by two-body abrasion, in which a tribolayer is formed, and then by three-body abrasion, in which partial removal and formation of the tribolayer occur dynamically over time, with the severity of the abrasions depending on the proportion of Ni infiltration aids and the applied load. [ABSTRACT FROM AUTHOR]

Community structure is essential for topological analysis, function study, and pattern detection in complex networks. As establishing community structure in a dynamic network is difficult, it gives a unique perspective in many interdisciplinary fields. Many researchers have explored the challenging technique that requires parameter specification and optimization for quality result. This study proposed an eco-system conceptual framework based on bird flock effect. Relying on the natural law of rule, we designed a dynamic community detection named DCDBFE. The design of algorithm was based on the three basic rules of bird flock: separation, alignment, and cohesion phase. Then, we provide an explanation of similarity measure used between vertices to identify the modules attraction. DCDBFE employs an incremental community detection approach to repeatedly detect communities in each network snapshot or time step. The contributions are obtained for high quality community detected, free-parameter and well stability. To test its performance, extensive experiments were conducted on both synthetic and real-world networks. The outcomes demonstrate that our approach can effectively find satisfaction from each time step by comparison with the other well-known algorithms. [ABSTRACT FROM AUTHOR]

Despite its prominence and functionality in academic writing, cohesion is under-researched in academic genres, including research articles (RAs). Moreover, there is little cross-disciplinary research on cohesion in academic discourse. Thus, this study aimed to investigate cohesion in the discussion section of RAs at sentence, paragraph and text levels, across three disciplines (i.e., applied linguistics, chemistry, and economics). To this end, 24 indices of local, global, and text cohesion were analyzed in a corpus of 300 discussion sections (100 from each discipline). MANOVAs identified significant cross-disciplinary variations in local, global, and text cohesion. Specifically, indices of local cohesion were generally higher in applied linguistics discussions, but measures of global, and text cohesion were mostly higher in chemistry and economics texts, respectively. Random forest modeling revealed that negative connectives were the most powerful classifiers of applied linguistics discussions, whereas adjacent sentence overlap noun synonyms and positive connectives were the best predictors of chemistry and economics discussions, respectively. These results are discussed with a view to offering theoretical and pedagogical implications for English-for-specific-purposes researchers and practitioners. • Indices of local cohesion were generally higher in applied linguistics discussions. • Chemistry and economics feature global and text cohesion respectively. • Local cohesion indices were the best classifiers in the three disciplines. • Random forest modeling complemented MANOVA results. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Milk protein powders are widely used ingredient in processed food products, meanwhile, characterization of powder functionalities is of technical challenge to the manufacturers of ingredients and consumer foods. Rapid evaluation methods or indicators are needed to fill the mentioned technological gap. This study aimed to investigate correlations between a series of powder functionalities and powder surface properties, which may be characterized using a relative rapid method. Six types of milk protein powder with 2 different batches were used as samples in this study. The powder wettability was determined based on a modified International Dairy Federation method. Powder flowability was determined using the Warren Spring cohesion measured by rheometer. The dispersibility was indicated by the median particle size at a designated dispersing time point. Regarding the surface properties, the contact angle of powder samples was determined by the sessile drop method using both water and diiodomethane as reference liquids. Subsequently, surface free energy was computed through the Owens, Wendt, Rabel, and Kaelble model. Pearson correlation analysis revealed meaningful correlations between surface properties (e.g., surface free energy, cohesion work, and adhesion work) and powder functionality attributes (e.g., wettability and flowability). This study suggests that the wettability and flowability of milk protein powders can be indicated by powder surface energy–related parameter, such as work of cohesion. [Display omitted] [ABSTRACT FROM AUTHOR]

Unsaturated soils exhibit distinct physical and mechanical characteristics compared to dry or saturated soils. Ignoring the influence of unsaturation (matric suction) and assuming either dry or saturated conditions can lead to unreliable predictions of pile behavior in unsaturated soils. In this study, the pullout capacity of different physical model piles driven in unsaturated Kaolinite-Bentonite matrices is investigated. A series of lab-scale pullout tests were carried out to examine the influence of matric suction, pile type, pile L/D ratio, and undrained cohesion (cu) of soil on the ultimate pullout capacity of model piles. Soil samples were prepared and compacted in a tank, and holes were created using a pile. Four model piles (solid and hollow stainless steel) were driven into the holes, ensuring proper spacing. Incremental loading was applied until the piles slipped out, with displacement measured by an LVDT. The pile pullout capacity increased with increased matric suction and undrained cohesion. The uplift capacity increased by 50% to 136% as matric suction increased by 157.97% as the compaction state was changed from 0.95γd(max) on the wet side of optimum moisture content (OMC) to 0.95γd(max) on the dry side of OMC of the compaction curve. However, for the compaction state of 0.90γd(max), the matric suction increased by 398.80%, leading to a 275% to 800 % increase in the uplift capacity. As the cohesion of the five samples increased from 17.84 kPa to 137.84 kPa, the uplift capacity of all the model piles increased. In Kaolinite-Bentonite mixes compacted on the dry side of OMC, hollow model piles resisted higher pull-out loads than solid model piles. The increase in uplift capacity was found to be in the range of 11.11% to 75% for different combinations of pile type and compaction density (matric suction). The results from the study imply a strong influence of matric suction, undrained cohesion, L/D ratio, and pile type on pullout capacity for piles driven in unsaturated Kaolinite-Bentonite mix. [ABSTRACT FROM AUTHOR]

Borgatti and Everett's model (2000) remains the prevailing standard for identifying categorical core-periphery structures in empirical networks, yet this method poses two significant issues. The first concerns the handling of inter-categorical ties—those linking core and periphery actors. The second problem is the model's definition of the ideal core as a complete block or clique, which can be overly stringent in practical applications. Building on advancements in direct blockmodeling, we propose modifications to address these shortcomings. To better handle inter-categorical ties, we replace the traditional cell-wise correlation approach with one based on exact- and minimum-density blocks. To relax the constraint of a fully connected core, we introduce the p-core, a proportional adaptation of the k-core/k-plex cohesive subgroups, providing greater flexibility in defining the level of cohesion required for core membership. We illustrate the advantages of these enhancements using both classic network examples and synthetic networks. • This paper addresses two limitations in Borgatti and Everett's popular model for categorical core-periphery structures. • We introduce a method that replaces the existing cell value correlation with exact- and minimum-density ideal blocks. • We implement the p-core, a proportional version of the k-core/k-plex, as a more flexible ideal block for core cohesion. • All core-periphery models mentioned in this article are implemented in Socnet.se, a novel client for direct blockmodeling. [ABSTRACT FROM AUTHOR]

For marine soft soil under the periodic wave loading, the pore water content in soil suffering dry-wet cycle for a long time, which affects its microstructure and macroscopic mechanical strength, resulting in insufficient bearing capacity and excessive deformation of soft soil. To reveal the microstructural characteristics and strength attenuation law of marine soft soil under dry-wet cycle condition, electron microscopy scanning and direct shear tests under different times of dry-wet cycles were carried out, and the mathematical equations of pore structure and strength parameters were established based on fractal theory. The research results showed that: (1) The pore structure changed considerably after the first dry-wet cycle, and then changed gently with the increase of dry-wet cycle times, which was reflected by the fractal dimension D value decreases to a constant value gradually. (2) The shear strength of the soil diminishes with an increase in the number of dry-wet cycle times, and the maximum attenuation occurs after the first dry-wet cycle. (3) The relationship between cohesion (c), internal friction angle (φ), and fractal dimension (D) is exponential, with the curve shapes being concave and convex, respectively. [ABSTRACT FROM AUTHOR]

Reinforcing calcareous sands with geogrids is a potentially effective method for large-scale geotechnical constructions in coastal lands. The breakable nature of polygonal calcareous sands determines the complex particle-geogrid interactions. A three-dimensional numerical model of geogrid reinforced calcareous sand (GRCS) was established to investigate the potential mechanical laws based on the discrete element method (DEM), and the reasonableness of the numerical model was verified by comparing with the indoor triaxial test. It follows that the macro-microscopic mechanical behavior of GRCS under the influence of aperture size and tensile resistance of geogrids was further investigated via effective DEM simulations. The presented results show that the decreased aperture size and increased tensile resistance are beneficial to enhance the macro-mechanical properties of GRCS, including strength, internal friction angle and pseudo cohesion. Particle crushing is mainly affected by shear strain and confining pressure. The bulging deformation of GRCS is partially suppressed due to the confining effect of geogrids. Besides, the source of strength enhancement of GRCS is revealed based on the microscopic particle-geogrid interactions, and the calculation method of horizontal and vertical additional stresses in the reinforced soil element considering the effects of tensile resistance and aperture size is further established. • A DEM model is established for geogrid reinforced calcareous sand. • Aperture size and tensile resistance effects are considered. • The distribution and evolution of particle crushing are characterized. • The macro-micro mechanical behavior of GRCS is revealed. • An additional stress calculation method is developed. [ABSTRACT FROM AUTHOR]

• The optimal plastic content for MSW is 6–9 %. • Stress path influences the optimal plastic content. • The influence patterns of particle size distribution on MSW. • Traditional well-graded criteria are unsuitable for MSW. Plastics within municipal solid waste (MSW) are non-degradable. As MSW continues to degrade, the relative content of plastics rises, and particle gradation may also change. Moreover, throughout the landfilling process, MSW is subjected to various stress conditions, potentially influencing its mechanical properties. This study explored the effects of varying plastic contents, different particle gradations, and distinct stress paths on the mechanical properties of MSW, and consolidated drained triaxial tests of 42 groups of reconstituted MSW specimens were conducted. The results showed that there was an optimal plastic content of 6–9 % for MSW, where the shear strength of MSW was higher than that of MSW with other plastic contents. When the stress path changed from TC45 to TC72, the optimal plastic content of MSW changed from 6 % to 9 %. As the plastic content increased, both the cohesion and internal friction angle of the MSW initially increased, then subsequently decreased. The impact of plastic content on cohesion was more pronounced than on the internal friction angle, especially at larger strains. Under various stress paths, MSW with distinct particle size distributions demonstrated diverse stress–strain behaviors. Traditional criteria for evaluating well-graded conditions in soils are not suitable for MSW. The effect of gradation on the cohesion of MSW is essentially due to the predominant role of fiber content; the relationship between gradation and the internal friction angle in MSW is complex and correlates closely with the content of both coarse and fine particles, as well as fibers. This study serves as an essential reference for predicting deformations in landfills and analyzing the stability of landfill slopes. [ABSTRACT FROM AUTHOR]

In order to enhance the limited information on elevated temperature stability of MAX phase materials, Ti 2 AlN MAX phase composites were fabricated in a two-step procedure and subsequently tested regarding their oxidation and creep behavior. Furthermore, commentary testing on material enhanced with different amount of Al 2 O 3 fibers was performed. The compressive creep was investigated in the temperature range of 900–1200 °C under stresses ranging from 20 to 100 MPa, with a loading direction parallel and perpendicular to the compression direction during sintering. The oxidation behavior was characterized, demonstrating excellent oxidation resistance of the samples up to 1200 °C. Supported by microstructural investigations, the impact of the texturing of the matrix grains, the content and the orientation of Al 2 O 3 fibers, as well as that of the interfaces between matrix grains and the Al 2 O 3 fibers were investigated. De-cohesion and cracks formed at the triple junctions of the MAX phase grains indicate grain boundary sliding as predominant creep mechanism for the composites. [ABSTRACT FROM AUTHOR]

One of the aspects that affect structure stability is the soil--structure interaction. A good example of this interaction can be witnessed in footings, in which the properties of the soil surrounding the structural parts and the structural parts themselves affect the engineering behavior of the interaction between concrete footings and the soil. Contact stress distribution represents such interaction. However, contact stress distribution beneath concrete footings does not solely rely on the soil type and behavior of footing in working limit state, but also on the variation in the concrete footings stiffness after cracking. The main purpose of this research is to investigate the effect of the reduction in the concrete footing stiffness due to cracking on the contact stress distribution beneath concentric isolated footings resting on cohesive soil. In this respect, numerical simulation and validation was carried out using a non-linear finite element program 'Abaqus'. A parametric study was conducted to extend this study by including soil cohesion, internal friction angle, rebars yield strength, and foundation depth as investigated parameters. The concrete foundation behavior and failure mode were analyzed. The findings of this research indicate that the different variations of cracks in reinforced concrete showed different shapes of contact stress distribution. [ABSTRACT FROM AUTHOR]

It is extremely necessary to fully understand the mechanical properties of hydrate-bearing sediments before the commercialization of hydrate. However, few studies have explored the effect of matrix composition on mechanical behavior. In this paper, seabed clay recovered from the Shenhu Sea in the hydrate deposit area of the South China Sea and quartz sand were used as the matrix skeleton to remold hydrate-bearing clayey-sandy sediments (HBCSS). A series of triaxial tests were then carried out to investigate the effect of matrix composition (clay and fine contents) on the strength behavior of HBCSS. The results show that the fine can fill the pores and thus increase the density, which in turn enhances the strength and stiffness of HBCSS and makes the stress-strain relationship more easily softened. The lubrication of clay can significantly change the contact relationship between particles, induce strain hardening and reduce stiffness. Cohesion and internal friction angle are positively and negatively correlated with clay content, respectively. A new concept of the hardening index was proposed, which has a better quantitative description of the hardening or softening of the stress-strain relationship. The strength behavior of HBCSS is the result of the coupling of various factors. • The effects of fine and clay on the strength behavior of HBCSS are illustrated. • The influence essences of fine and clay are the filling and lubricating effects respectively. • Particle-scale shearing mechanisms are revealed. • A new hardening index is proposed to quantitatively analyze hardening or softening. [ABSTRACT FROM AUTHOR]

Hexagonal boron nitride (hBN) with excellent self-lubrication performance is expected to relieve the friction resistance and wear of NiCr–Cr 3 C 2 coatings. However, the poor wettability of hBN with most materials makes it difficult to fabricate NiCr–Cr 3 C 2 -hBN composite coating with good cohesion strength. In this study, hBN was firstly pretreated through magnetron-sputtering aided Ni plating to form hBN@Ni particles. Then, NiCr–Cr 3 C 2 -hBN@Ni powder was prepared by spray granulation. Next, corresponding coatings were prepared through supersonic atmosphere plasma spraying. It was found that in comparison with NiCr–Cr 3 C 2 -hBN coating, the NiCr–Cr 3 C 2 -hBN@Ni coating exhibited a decreased porosity (from 3.6% to 0.3%), elevated cohesion (from 52.78 N to 62.11 N), and the wear rate decreased by an order of magnitude. It was concluded that hBN@Ni can effectively improve the component interface inside powder, enhance the cohesion of molten in-flight particles, and make the internal structure of the coating denser. [ABSTRACT FROM AUTHOR]

Magnesium phosphate-based cements (MPCs) are nowadays regarded as promising materials in the field of bone repair. The inclusion of Sr ions in the formulations may represent a valuable strategy to improve their bone regeneration performances, but the effect that such ion exerts on the physico-chemical properties of the material have not been investigated so far. In this work we describe the development of Sr-MPCs obtained including Sr ions in different forms, i.e., using Sr-substituted tri-magnesium phosphate precursor powder or including in the formulation Sr-based salts (SrCl 2 and SrHPO 4). The materials were characterized both in the form of pastes and hardened cements, finding that according to the type of Sr precursor used we can tune the setting time, the amount of binding phases in the cements, their morphology and thermal behavior. The dissolution behavior and the release kinetics of Mg2+ and Sr2+ can as well be modulated, and in particular the use of SrCl 2 in the formulation leads to a higher dissolution and a faster release of a significant amount of both Mg2+ and Sr2+, compared to the other samples. Given the unsatisfying performances obtained during the injectability and anti-washout tests, we also included two polymeric additives, namely poly(N-isopropylacrylamide) and mucin, in the Sr-MPCs formulations. The results demonstrate that it is possible to obtain Sr-MPCs with promising properties for applications as bone cements, that can be tuned according to the form under which Sr is included in the formulation. In addition, mucin markedly improves the cohesion and injectability of the Sr-MPC pastes, providing a simple but effective strategy to develop materials of interest in the orthopedic field. [ABSTRACT FROM AUTHOR]

Usage of computational tools to quantify language disturbances among individuals with psychosis is increasing, improving measurement efficiency and access to fine-grained constructs. However, few studies apply automated linguistic analysis to life narratives in this population. Such research could facilitate the measurement of psychosis-relevant constructs such as sense of agency, capacity to organize one's personal history, narrative richness, and perceptions of the roles that others play in one's life. Furthermore, research is needed to understand how narrative linguistic features relate to cognitive and social functioning. In the present study, individuals with schizophrenia (n = 32) and individuals without a psychotic disorder (n = 15) produced personal life narratives within the Indiana Psychiatric Illness Interview. Narratives were analyzed using the Coh-Metrix computational tool. Linguistic variables analyzed were indices of connections within causal and goal-driven speech (deep cohesion), unique word usage (lexical diversity), and pronoun usage. Individuals with schizophrenia compared to control participants produced narratives that were lower in deep cohesion, contained more first-person singular pronouns, and contained fewer first-person plural pronouns. Narratives did not significantly differ between groups in lexical diversity, third-person pronoun usage, or total word count. Cognitive-linguistic relationships emerged in the full sample, including significant correlations between greater working memory capacity and greater deep cohesion and lexical diversity. In the schizophrenia group, social problem-solving abilities did not correlate with linguistic variables but were associated with cognition. Findings highlight the relevance of psychotherapies which aim to promote recovery among individuals with psychosis through the construction of coherent life narratives and increasing agency and social connectedness. [ABSTRACT FROM AUTHOR]

Dysphagia, a widely suffered disease mainly by seniors, causes food swallowing-related issues such as choking, aspiration, aspiration pneumonia, and even death. Designing special diets such as thickened fluids (e.g. water, milk, soups, and juices) is an essential means of managing swallowing problems for people with dysphagia. This review discusses intrinsic influencing factors (e.g. surface tension, viscosity, yield stress, and the cohesion of fluid food boluses) and external influencing factors (e.g. temperature, fluid volume, saliva secretion, and body posture) that influence the swallowing behaviors (e.g. oropharyngeal flow velocity, residual amount, and aspiration risk) of thickened fluids. Subsequently, computer models assessing the swallowing features of thickened fluids (Newtonian/non-Newtonian) are highlighted, including mesh-based methods (e.g. finite element method (FEM)) and mesh-free methods (e.g. smooth particle hydrodynamics (SPH) and moving particle semi-implicit (MPS)). Also, current challenges and prospects of computer modeling in the development of dysphagia fluid foods are proposed. The swallowing behaviors of thickened fluids are closely linked to intrinsic and external factors. Increasing the viscosity and cohesiveness can slow the flow of the swallowed fluid bolus and suppress fluid splashing, thus providing more response time for the nerve system and muscles to reduce choking and aspiration risks. Such information is vital for establishing mesh-based and mesh-free computer models used to inspect the swallowing process of thickened fluids. These computer models are potentially useful for developing dysphagia foods, especially thickened fluids, with tailored swallowing performance. [ABSTRACT FROM AUTHOR]

Ice slurries are phase change materials extensively used in refrigeration technology. This work describes an experimental study and empirical modeling that was carried out to characterize the rheological behavior of ice-in-oil slurries. Decane and crushed ice were mixed to prepare test samples with ice volume percentages ranging from 3.5 to 17.7%. The size of the particles was 0.27 ± 0.13 mm. The viscosity measurements are performed at −2.5, −5.0, and −10.0 °C using a rotational viscometer with a three-bladed impeller. The maximum relative velocity was ∼ 3.1 for 17.7% vol. concentration. A Bingham viscoplastic model was used to predict the rheological behavior of ice-in-oil slurries. The fractal dimension, packing limit, size of ice particles, and inter-particle cohesive forces were all considered in rheological calculations to make the model extensively applicable. The model accuracy is then examined using third-party experiments and experimental findings from the current study. The model appears to be a viable tool for predicting the viscosity of ice-in-oil slurries. • We measure the apparent viscosity of an ice-in-decane slurry. • The concentration of ice is 3.5...17.7%, the temperature is −2.5...−10 °C. • The average size of the ice particles is 270 μ m. • The maximum relative velocity was 3.1. • Bingham viscoplastic model fits the experiments. [ABSTRACT FROM AUTHOR]

Hydrate exploitation requires a deep understanding on the mechanical behavior of methane hydrate-bearing sediment (MHBS). Due to the low permeability of overlying strata, partial MHBS likely exhibit failure behavior under undrained condition. Therefore, it is essential to understand the undrained shear strength and excess pore pressure behavior of MHBS for facilitating the evaluation of the stability of hydrate-bearing layer during methane hydrate recovery. This study conducted several undrained triaxial compression and hydrate dissociation tests on methane hydrate-bearing sand specimen to analyze the shear strength and excess pore pressure characteristics of MHBS under undrained condition. The experimental result shows that hydrate saturation and initial effective confining pressure significantly affect the undrained mechanical behavior of MHBS. Hydrate saturation increases the shear strength and negative excess pore pressure. High initial effective confining pressure also enhances the shear strength but suppressed the negative excess pore pressure. Hydrate saturation has a minimal effect on the undrained internal friction angle but remarkably enhances the undrained cohesion. The effective internal friction angle and cohesion exhibits an increase with the increase in hydrate saturation. Notably, completely different from the common soil, the effective undrained strength indexes are not equivalent to the drained strength indexes for MHBS, which should be careful in evaluating the stability of methane hydrate-bearing layer. In addition, the hydrate dissociation test by thermal stimulation method concludes that hydrate dissociation induces the positive excess pore pressure, axial compression, and volume expansion under undrained condition. The large deviatoric stress enhances volume expansion of MHBS but hinders the generation in excess pore pressure during hydrate dissociation. These findings significantly contribute to the safe exploitation process of methane hydrate. • Undrained triaxial compression and dissociation tests were conducted on MHBS. • Hydrate saturation increases shear strength and negative excess pore pressure. • High initial effective confining pressure enhances shear strength but suppresses negative excess pore pressure. • Effective undrained strength indexes are not equivalent to drained strength indexes for MHBS. • Hydrate dissociation induces positive excess pore pressure and deformation of MHBS. [ABSTRACT FROM AUTHOR]

• Absorber coating degradation depending on the heating and cooling rate. • Optical properties degradation when the coating is removed. • Mismatch effect and substrate oxidation promote degradation. • To use mix rule to estimate the surface absorptance. Concentrating solar power (CSP) is emerging as an increasingly important component of renewable energy. CSP systems are being widely adopted in the establishment of large-scale thermal power plants, with an increase in the number of successfully operating demonstration systems. Special coatings are generally used in various types of receivers for solar collector systems. Selective coatings are used for receivers intended to be operated at low or medium temperatures. Similar selective coatings are not currently available for application under high temperatures. In such cases, high-temperature absorbing coatings are generally used to improve the thermal efficiency of the receiver and protect their tubes from oxidation. It is worthwhile to observe the behaviour of such coatings when exposed to high fluxes for extended periods, in order to develop more efficient technologies. Currently, the essential properties for characterizing the paint are absorptivity, emissivity, and structural integrity of the coating (adhesion and cohesion). Good understanding of the behaviour of this paint under representative operating conditions would help to improve the design of the plant, maintain its performance and maintain the thermal efficiency of the receiver. The principal objective of this study was to provide extensive knowledge of the durability and variation of the optical properties of Pyromark when it is consolidated with improved methods. No degradation or loss of optical performance was observed at temperatures under 700 °C. The substrate affected the crystalline structure of an initial coating at high temperatures owing to the diffusion of metal ions. Concentrated solar radiation was the main factor that affected the integrity of the coating. At concentrations higher than 550× suns, a significant area of the irradiated samples was found to be uncoated. These results can be used to design more accurate latest generation receivers to improve the performance of this technology. [ABSTRACT FROM AUTHOR]

A series of SiC/Al composites with different contents of 3-dimensional graphene networks (3DGN) were prepared by using mechanical alloying (MA) and spark plasma sintering (SPS). The effects of 3DGN on the microstructure, mechanical properties and corrosion behaviors of SiC-3DGN/Al composites were investigated. The results show that the 3DGN can substantially enhance the synergistic strength-toughness of SiC/Al composites. Compared with SiC/Al composites, the SiC-3DGN/Al composites demonstrate stronger interface cohesion, and an increase in hardness (56.5%), density, ductility and corrosion resistance in NaCl solution. The reason is that 3DGN results in enhanced interface cohesion by reducing defective interface between the reinforcement and the matrix. [ABSTRACT FROM AUTHOR]

We developed and verified a high-performance open-source discrete element method (DEM) solver with simultaneously-supported feedstock-specific interaction models, including bonded-sphere, liquid bridge, cohesion, and non-linear contact models. Our solver uses parallel data structures on hybrid central and graphics processing unit (CPU/GPU) architectures, with favorable strong scaling performance observed for large problem sizes comprised of O (100 M particles), and 4X single-node GPU speedup. The particles for corn stover feedstock were conceptualized and calibrated based on experimental measurements and results. Sensitivity analyses demonstrate that the mass flow rate from a wedge hopper is governed primarily by moisture content, friction coefficient, and cohesion energy density. The model is used to reproduce experimentally observed hopper jamming results, highlighting that the experimental no-flow trends can only be achieved by using non-spherical particles, liquid bridge and cohesion models, highlighting the importance of using concurrent feedstock specialized models for the effective representation of biomass material handling problems. [Display omitted] • Developed an open-source DEM solver with strong CPU/GPU scaling for >100 M particles. • Corn stover particle types and conceptualized and simulated using experimental data. • Sensitivity analysis conducted to identify DEM parameters that govern flowability. • DEM solver is validated experimentally via corn stover hopper discharge experiments. • Bonded sphere, moisture, and cohesion models are all required to predict biomass flow. [ABSTRACT FROM AUTHOR]

• Irradiation on fracture behavior of alumina scales formed on FeCrAl ODS alloy has been investigated. • Preferential intergranular fracture dominates the fracture of irradiated alumina scales in nanoindentation. • Irradiation induced REs segregation and Ti/TiC precipitation on alumina grain boundaries. • Cohesion strength of alumina scales formed on FeCrAl ODS alloys has been efficiently evaluated by DNS compression tests. The design of FeCrAl ferritic oxide dispersion strengthened (ODS) alloys is based on the formation of a stable alumina scale, which is expected to protect the alloys from extreme heat and corrosion in nuclear applications. To ensure reliable alumina protection in nuclear environment, it is indispensable to concern the radiation tolerance of the alumina scales formed on the FeCrAl ODS alloys. The present study investigates the effect of Fe ions irradiation on fracture modes and grain boundary cohesion of the alumina scales in conjunction with nano-impact tests and micro-double notch shear (DNS) compression tests. Pre-oxidation was carried out in air at 1000 °C to form an α-alumina layer on the surface of Fe-15Cr-7Al-0.5Y 2 O 3 –0.4Zr (wt.%) ferritic ODS alloy, followed by 6.4 MeV Fe3+ ion beam irradiation at 500 °C. Based on the microstructural characterization of the cross-sectional micrographs of nanoindentation imprints on the alumina scales, it was confirmed that the irradiation on the alumina scales resulted in significant intergranular fracture in nanoindentation, whereas the unirradiated alumina scales showed transgranular fracture. The elemental distribution around the alumina grain boundaries was elucidated with the aid of scanning transmission electron microscopy (STEM) and atom probe tomography (APT) observations, and obvious segregation of reactive elements (REs) and intergranular Ti/TiC precipitation were observed after irradiation, indicating the link between the microstructural evolution and the fracture behavior of the alumina scales. The detailed grain boundary cohesion of alumina scales before and after irradiation was accurately measured by the micro-DNS compression tests, and the results showed that the cohesion strength of the alumina decreased significantly after the Fe ions irradiation. [ABSTRACT FROM AUTHOR]

Water damage is the primary cause of premature deterioration of asphalt pavement, leading to a decrease in its durability. Hence, it is essential to utilize an effective approach for quantifying water damage to extend the lifespan of roadways. Previous methodologies for evaluating the water sensitivity of asphalt mixtures were either less accurate or time-consuming. This review article provides a comprehensive overview of the principles and factors that influence various laboratory and field test methods, as well as the integration of theoretical analysis and test methods for detecting water damage and quantitatively evaluating loose asphalt mixtures and compacted asphalt mixes using digital image processing technology. It also explores the microstructure change of the asphalt mixture at different stages of the process and the influence of water penetration on the inside of the material through the data collection of water damage images. Various image processing techniques, including visual assessment, monochrome image, grayscale image, colorful picture, and light reflection image, effectively provided scientific and precise evaluations of asphalt mixtures using advanced data analysis and image processing software. An optimal correlation was demonstrated between the boiling water test (BWT) and the rolling bottle test (RBT) of loose asphalt mixtures when recognizing color interference in grayscale image processing. Image-based direct tensile strength (DTS) evaluation revealed that the main variables affecting water resistance are adhesion and cohesion degradation. Image-based indirect tensile strength (ITS) tests explained a significant positive relationship between cohesion damage and tensile strength ratio (TSR). In contrast, the aggregate broken area exhibited a negative connection, highlighting its importance in assessing water resistance. Furthermore, the implementation of artificial intelligence can improve the accuracy of identifying asphalt adhesion to aggregate surfaces. This study presents a theoretical framework for rapidly determining water damage, scientifically evaluating asphalt materials, and establishing a more precise qualitative standard for designing and optimizing water damage-resistant materials in road construction. [ABSTRACT FROM AUTHOR]

The shear strength of rock joints under dynamic normal load (DNL) conditions is quite different from that under constant normal loading (CNL) conditions. However, existing studies seldom involve the shear strength prediction of rock joints under DNL conditions. Therefore, a series of shear tests for rock joints under DNL conditions were carried out. The evolutions of the shear strength parameters, including both cohesion and internal friction angle, with dynamic loading amplitude and frequency were investigated according to the experimental results. A shear strength criterion for rock joints under DNL conditions was developed. The proposed model was verified by comparing the theoretically predicted values with experimental results, both of which showed excellent agreement. Additionally, the strength criterion is utilized to predict the peak shear strength under CNL and new DNL conditions. These prediction results were further validated by experimental methods, which extend the applicability of the proposed strength criterion. This study can provide valuable references for the stability evaluation of rock formation engineering and geological hazard warning under dynamic load disturbance. • The relationship between the strength parameters and the dynamic normal load was established. • The shear strength criterion for rock joints under dynamic normal load conditions was proposed. • The proposed criterion predicts the experimental results well for shear strength under dynamic and/or constant normal load conditions. [ABSTRACT FROM AUTHOR]

Neighborhood characteristics can influence cardiometabolic health, including during the perinatal period. However, maternal health research has largely examined the influence of objective neighborhood measures, limiting insights into psychological and social processes. We examined associations of perceived neighborhood disorder and social cohesion with maternal cardiometabolic risk 1 year postpartum and explored potential pathways of psychological distress and physical activity. A predominantly low-income sample of Black, Latina, and White postpartum women (n = 987) were participants in the Community Child Health Network study. Women reported on neighborhood characteristics at 1 month postpartum and on symptoms of depression, anxiety, and posttraumatic stress disorder and physical activity at 6 months postpartum. Biometrics and biological samples were collected at 1 year postpartum, including blood pressure, height, weight, and dried blood spots for cardiometabolic biomarkers (e.g., C-reactive protein, glycosylated hemoglobin). In this pre-registered study, we used structural equation modeling to estimate latent variables for disorder, social cohesion, distress, physical activity, and cardiometabolic risk. We fit a parallel mediation model to test associations between latent neighborhood factors at 1 month postpartum, distress and physical activity at 6 months postpartum, and cardiometabolic risk at 1 year postpartum. Greater social cohesion, but not disorder, was significantly associated with lower distress and greater physical activity. However, there were no significant associations between disorder or social cohesion with subsequent cardiometabolic risk nor evidence for indirect effects of distress or physical activity. Results suggest that social cohesion may be more pertinent than disorder for health-relevant behavioral mechanisms in postpartum women. • Neighborhood factors are contextual elements that can influence postpartum health. • Social cohesion related to postpartum psychological distress and physical activity. • Neither disorder nor cohesion was linked to cardiometabolic risk 1 year postpartum. • Promoting social cohesion may positively impact health-related behavioral mechanisms. [ABSTRACT FROM AUTHOR]

A new strategy to predict the different failure processes of reinforced concrete members via macroscale modeling is proposed. In the mesh fragmentation framework , the technique relies on the use of condensed high aspect ratio interface elements and two independent damage models (tensile and shear-frictional), enabling specific energy dissipation for each fracture propagation mode, as well as modeling the formation and propagation of multiple fractures in the concrete. Additionally, to simulate reinforced concrete members, coupling finite elements are incorporated to model the interaction between the concrete and steel reinforcements, considering appropriate bond–slip behavior. Uniaxial compression tests are carried out to assess the ability of the strategy to predict the failure mechanism of concrete and to study the influence of material parameters such as cohesion and friction angle. The predictions of reinforced concrete beams with different spans, cross sections, and reinforcements are in good agreement with the experimental results reported in the literature, particularly with respect to the failure modes. The experimentally observed relationships between the geometric parameters and failure modes (flexural, shear and crushing failure modes) of reinforced concrete beams can also be properly predicted via the proposed approach. • A numerical approach to represent different failure modes in RC beams is proposed; • Interface elements are ruled by two independent damage models; • This technique captures the formation and propagation of multiple cracks; • The use of CFEs allows effective bond-slip modeling with a lower computational cost; • The model predicts shear-compression, concrete crushing, and flexural failure modes; [ABSTRACT FROM AUTHOR]

To accelerate the replacement of damaged bridge expansion joints and minimize the impact on traffic, employing rapid hardening high performance concrete (RHHPC) as infilling materials is one competitive alternative. To this end, five groups of concrete considering different contents of sulfate aluminate cement (SAC) and steel fiber were designed to obtain the optimal RHHPC mixtures. Subsequently, a series of push-off tests were conducted to investigate the interfacial shear performance between RHHPC and normal concrete (NC), with the variables of interfacial treatment, shear reinforcement ratio, concrete strength, and curing age. The test results demonstrated that increasing the steel fiber contents enhanced both the compressive and tensile strength, but reduced the slump of fresh RHHPC. The increase in the SAC contents resulted in a significant decrease in setting time. The push-off tests failed by interfacial shear failure, accompanied with significant concrete cracking, spalling, or splitting. Both the ultimate load and residual load improved as the interfacial roughness, shear reinforcement ratio, concrete strength, and curing age increased. Based on the experimental results, a modified model considering the contributions of concrete strength, shear reinforcement clamping stress, and concrete cohesion was proposed to predict the interfacial shear capacity between RHHPC and NC. • A new formula was developed to predict the shear strength between the two concretes. • The new formula better predicts shear capacity than current standards for these concretes. • The formula considers concrete strength, aggregate interlock, and interface reinforcement ratio. • This concrete is ideal for rapid bridge joint repairs requiring early strength and fast hardening. [ABSTRACT FROM AUTHOR]

Evaluating and confirming a reduction in mixing and compaction (M&C) temperature upon Warm mix asphalt (WMA) modification can be challenging, particularly when assessing bitumen modified with chemical and water-based WMA additives that show no significant change in viscosity. On the other hand, many a times adoption of Manufacturer's recommended construction temperature is a norm. Therefore, (a) quantifying the temperature reduction with WMA additives is necessary to achieve sustainable goal and (b) there is need to develop methodology to evaluate M&C temperatures of WMA modified binders. Present study plans to modify the viscosity grade (VG30) asphalt binder with 6 different types of WMA additives (Sasobit, Sasobit Redux, Wetbond, Rediset, Zycotherm, Zycotherm SP2), further this modified bitumen is used with basalt aggregates to prepare asphalt mixtures. Viscosity (by Rotational viscometer, Steady shear flow method), and other key parameters like gyratory compaction level (Super gyratory compactor), activation energy (Ea) (Arrhenius equation), surface free energy (SFE), work of cohesion, and wettability (Sessile drop method), were analysed to interpret temperature reduction with WMA modification. The results indicate that Sasobit-modified bitumen achieved a significant temperature reduction, as observed in the rotational viscometer analysis, the SSF method, and the Ea assessment. Wetbond had better results in gyratory compaction level and SFE approach (reduced surface tension and more workable asphalt mixtures upon modification). All other additives also showed significant variation in different approaches upon modification. Further correlation analysis explores the relationships between these parameters and attempts to predict mixing temperature based on strongly correlated parameters are also reported. [Display omitted] • Warm Mix Asphalt Technology as sustainable approach for asphalt construction. • Lack of understanding regarding the determination of reduced mixing temperatures on WMA modification. • Different approaches to ensure reduction in mixing temperature. • Factors influencing temperature reduction upon WMA modification. • Correlation and prediction of temperature with highly correlated parameters. [ABSTRACT FROM AUTHOR]

This paper presents a mesoscale concurrent atomistic–continuum (CAC) simulation of crack initiation at the atomically structured grain boundaries (GBs) in bi-crystalline BCC iron (α -Fe) charged with hydrogen (H). By retaining the atomistic GB structure evolution together with the long-range dislocation-mediated plastic flow away from the GB in one model at a fraction of the cost of full molecular dynamics (MD), CAC enables us to probe the interplay between the atomic-level H diffusion, the nanoscale GB cavitation, crack initiation, growth, as well as the dislocation activities far away from the GB. Our several main findings are: (i) a tensile strain normal to the GB plane largely promotes the H diffusion towards the GB. (ii) the plasticity-induced clustering of H atoms (PICH) is identified as an intermediate process in between the H-enhanced localized plasticity (HELP) and H-enhanced de-cohesion (HEDE). (iii) PICH significantly amplifies the local stress concentration at the GB and decreases its cohesive strengths, and (iv) the GBs with different atomic structures fail differently. In detail, the H-charged Σ 3 GB fails through micro-twinning assisted void nucleation and coalescence, while the H-charged Σ 9 GB fails through crack initiation and growth accompanied by dislocation emission. Compared with nanoscale molecular dynamics (MD) simulations, the mesoscale CAC models get one step closer to the experimentally measurable length scales and thus predict reasonably lower GB cohesive strengths. This research addresses one key aspect of how H impacts the GB cohesive strengths in α -Fe. It offers insights into the multiscale processes of hydrogen embrittlement (HE). Our findings highlight the importance of using concurrent multiscale models, such as a combination of CAC, crystal plasticity finite element (CPFE), and cohesive zone finite element method (CZFEM), to understand HE. This will, in turn, support the development of new strategies for mitigating HE in a variety of engineering infrastructures. [Display omitted] • PICH bridges HELP and HEDE, playing a key role in hydrogen embrittlement (HE). • PICH causes high local stresses at GBs, reducing strength and causing failure. • H-charged Σ 3 fails via micro-twinning; Σ 9 fails via dislocations and cracks. • MD overestimates GB strength; CAC accounts for long-range internal stresses. [ABSTRACT FROM AUTHOR]