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Anticrack propagation in snow results from the mixed-mode failure and collapse of a buried weak layer and can lead to slab avalanches. Here, authors reproduce the complex dynamics of anticrack propagation observed in field experiments using a Material Point Method with large strain elastoplasticity.

The fractography and mechanical behaviour of fatigue crack propagation in the heat-affected zone (HAZ) of AISI 4140 steel welded using the shielded metal arc process was analysed. Different austenitic grain size was obtained by normalizing performed at 1200 °C for 5 and 10 hours after welding. Three point bending fatigue tests on pre-cracked specimens along the HAZ revealed that coarse grains promoted an increase in fatigue crack growth rate, hence causing a reduction in both fracture toughness and critical crack length, and a transgranular brittle final fracture with an area fraction of dimple zones connecting cleavage facets. A fractographic analysis proved that as the normalizing time increased the crack length decreased. The increase in the river patterns on the fatigue crack propagation in zone II was also evidenced and final brittle fracture because of transgranular quasicleavage was observed. Larger grains induced a deterioration of the fatigue resistance of the HAZ.

Efecto del mantequillado en las propiedades mecánicas de uniones soldadas disímiles en barras de refuerzo para estructuras de concreto RESUMEN En este trabajo se ha investigado la influencia de utilizar Inconel 182 como material de “mantequillado” en las propiedades mecánicas de uniones disimiles acero al carbono-inoxidable manufacturadas por soldadura con electrodo recubierto. Para ello se han empleado las siguientes técnicas: análisis microestructural, ensayos de microdureza Vickers y ensayos mecánicos de tensión. Se ha empleado el proceso de soldadura con electrodo recubierto por que es el más común en la soldadura de campo para la construcción. Los resultados demuestran que aun cuando las uniones disimiles sin “mantequillado” presentan defectos, sus propiedades mecánicas son superiores a las de las uniones soldadas con “mantequillado”. Esta metodología es propuesta para la rehabilitación de estructuras de concreto para ambiente marino con barras de acero como refuerzos. Palabras clave: mantequillado; uniones soldadas con materiales disimiles; propiedades mecánicas; microestructura; defectos. Effect of buttering in mechanical properties of dissimilar metal weld joints for reinforcement bars in concrete structures ABSTRACT In this work, the influence of Inconel 182 as buttering material in the mechanical properties of dissimilar metal welds between plain carbon steel and stainless steel bars welded using SMAW has been investigated using microstructural analysis, Vickers microhardness testing, and tensile tests. Welding with SMAW process is commonly applied in field welding of concrete structures; therefore this process was selected for this work. The results indicated that even if the joints contain defects generated by the welder, the mechanical properties of dissimilar welded joint without buttering are higher than the properties of joints with buttering. This methodology is proposed for the rehabilitation of concrete structures with steel bars as reinforcements, which are located in marine enviroments. Keywords: buttering, dissimilar metal weld joints; mechanical properties; microstructure; defects. Efeito da introdução de um terceiro material sobre as propriedades mecânicas das juntas soldadas entre aço carbono e aço inox, em barras de aço para estruturas de concreto RESUMO Este artigo investiga a influência da utilização de Inconel 182 como um terceiro material, nas propriedades mecânicas de diferentes aços inoxidáveis soldados a aços carbono com uso de eletrodo revestido. Para tanto foram usados os seguintes métodos: análise microestrutural, ensaios de microdureza Vickers e ensaios mecânicos de tensão. Tem sido empregado o processo de solda com eletrodo revestido, porque é o mais comum no campo de solda para a construção. Os resultados mostram que quando as uniões são realizadas sem esse terceiro material, as propriedades mecânicas são superiores às das juntas soldadas com auxílio do Inconel 182. Esta metodologia, ora criticada, tem sido proposta para a reabilitação de estruturas de concreto em ambiente marinho, com uso de barras de aço inox como reforços. Palavras-chave: juntas soldadas com materiais diferentes; propriedades mecânicas; microestrutura; defeitos.

Este trabajo se dirigió a determinar el efecto de tamaño y orientación en las propiedades de tracción y tenacidad a la fractura mediante las curvas CTOD-R, utilizando probetas estándar y miniatura de una placa de acero estructural. El estudio requirió la estimación de la función flexibilidad de las probetas miniatura a partir de la curva carga versus desplazamiento. Los resultados experimentales y estadísticos muestran que tanto el tamaño como la orientación afectan las propiedades mecánicas y la tenacidad a la fractura. Las probetas miniatura de tracción mostraron valores de resistencia ligeramente mayores que las estándar pero una menor ductilidad. Las curvas CTOD-R de las probetas miniatura mostraron ser sensibles a las variaciones de carga y al método de medición de la abertura y longitud de la grieta. Asimismo, se observó inconsistencia del efecto de tamaño en la tenacidad a la fractura en la orientación longitudinal circunferencial (LC), siendo las orientaciones cortas menos resistentes y tenaces que las otras direcciones.

This article examines the role of the Japanese financial system in the industrialisation of Japan over the period 1900-1970. The author explores the role of a financial system in the development of an industrialising economy and considers the pre-war and post-war financial system in Japan, arguing that although it underwent great transformations, the merits and demerits of each particular system must be viewed in terms of its current environment. JEL Codes: N15, N25, O14

This article examines the role of the Japanese financial system in the industrialisation of Japan over the period 1900-1970. The author explores the role of a financial system in the development of an industrialising economy and considers the pre-war and post-war financial system in Japan, arguing that although it underwent great transformations, the merits and demerits of each particular system must be viewed in terms of its current environment. JEL: N15, N25, O14

Background: Although the emotional and psychological impact of nurses' work had been identified before the COVID-19 pandemic, the pandemic aggravated risk indicators for their mental health., Aim: The objective of this study was to analyse the levels of anxiety, depression, post-traumatic stress and burnout of nurses in the Balearic Islands (Spain) during the pandemic to identify possible sociodemographic and related occupational factors., Design: A cross-sectional study of 892 nurses was conducted during four weeks from February to March 2021., Methods: Sociodemographic data related to the pandemic were collected and anxiety, depression, burnout and post-traumatic stress were measured with validated scales. A multivariate and predictive analysis was carried out with risk estimates., Findings: About 75.6% of the nurses had experience in COVID-19 units, and 49.1% had worked for more than 10 months in a COVID-19 unit. Nurses in COVID-19 units (hospital ward or ICU) were more likely to report emotional fatigue (OR 1.9, p < 0.001) and anxiety (OR 1.5, p = 0.021). In general, moderate post-traumatic stress was evident in general nurses (p = 0.027), and severe post-traumatic stress was evident in ICU nurses (p = 0.027). A 1.24-month reduction in COVID-19 patient care predicted reduced levels of emotional fatigue (5.45 points), depersonalisation (1.87 points) and post-traumatic stress (4.65 points) in nurses., Conclusion: Given the occurrence of new waves of COVID-19, the need to establish preventive strategies that focus on the personal and occupational characteristics related to these indicators and to implement urgent psychological support strategies is demonstrated., Impact: Given these findings, it is imperative solutions are urgently applied in order to prevent compounding risk to the health system., Competing Interests: None., (© 2021 Australian College of Nursing Ltd. Published by Elsevier Ltd.)