Letteratura scientifica selezionata sul tema "GEOGRID ORIENTATION"

Geosynthetics-reinforced soil (GRS) structures have been widely used for the prevention of geological hazards. As a recently introduced product, the triaxial geogrid has been confirmed to provide improved performance due to the more stable grid structure. This paper presents an evaluation of the mechanical behavior based on a series of laboratory tests. The unconfined tensile strength of biaxial geogrid and triaxial geogrid in different loading directions relative to the orientation of ribs was investigated. Then, more than 8 pullout tests were conducted on the triaxial geogrid specimens embedded in the compacted sand. The internal displacements along the geogrid length were monitored. The results show that the triaxial geogrid has been shown to provide nearly uniform tensile strength in all loading directions as compared with the biaxial geogrid. The triaxial geogrid deformation is mainly characterized by rib bending and nodal distortion along with an inward squeeze perpendicular to the pullout direction. The interface friction between the soil and the geogrid develops in a progressive mode, and an elasto-plastic-softening characteristic is detected experimentally due to the extensibility of geogrid.

To explore the initial orientation effect of ballast assembly on the reinforcement performance of the geogrid reinforced ballast, particles with random orientation and five prescribed rotational orientations were developed through particle flow code (PFC3D). The evolution laws of the pullout force and the principal directions of the normal contact force were systematically compared and analyzed. Furthermore, the mechanical responses such as pullout force, distribution of axial force, displacement vectors, force chain, and mesoscopic fabric were discussed. According to the displacement vectors of the ballast particles, the average thickness of the stable shear band is determined. The inherent relationships among the force chain, the rotational angle of the normal contact force, and the mesoscopic fabric parameters are revealed. The results show that the pullout force of specimens with the initial orientation of 45° increases monotonously during the pullout process, and the peak value of pullout force appears at the end of the test. The mesostructural analysis also confirms that the evolution of the principal direction of contact normal force is relatively steady during the pullout process, indicating that the specimen with 45° orientation possesses higher systematic stability and ductility. Moreover, the optimum interval from 56.68° to 57.30° is observed to remain in a self-adapting state for ballast assembly.

The paper investigates how refugees settled in rural Norway and Denmark experience and interact with their new rural places of residence. Theoretically, the paper finds inspiration in “phenomenology of practices” (Simonsen, Prog. Hum. Geogr., 2012, 37, 10–26), which emphasizes the bodily and sensory experiences of daily life that spur feelings of, for example, “orientation” or “disorientation”. The empirical material is based on fieldwork and qualitative interviews with refugees and local volunteers in 2016/2017/2019 in small towns in the rural north of Norway and rural Denmark. There are several differences between the Norwegian and Danish rural areas, in relation to distances, climate and population density. Nonetheless, the ways in which the rural areas are experienced from within, by refugees settled there, show surprisingly many similarities. Many of the informants, in both the Norwegian and Danish cases, initially expressed frustration at being placed in rural areas without having any say in the matter. Those who were former city-dwellers especially experienced moments of disorientation, as their encounters with Nordic rural life were experienced as the opposite of their urban backgrounds. Limiting structural conditions very much shape the everyday lives of refugees in the first years, when they do not have a car or the financial capacity to find their own house. They feel stressed, with busy everyday lives made up of long commuting hours on public transport. In these first years of uncertainty, the dark and harsh weather very much adds to the feeling of stress and insecurity. What seem to add “orientation” are social relations with other refugees and local volunteers organizing activities.

AbstractRecent debates in political ecology have sought to highlight and excavate the complex connectivity between ecological and carceral harms (e.g. Heynen and Ybarra in Antipode 53:21–35, 2021; Pellow 2021; Pulido and De Lara in Environ Plan E Nat Space 1:76–98, 2018; AAA = Brock and Stephens-Griffin, IDS Bulletin, 2017). ‘Abolition ecology’ presents an approach through which to explore, unravel and resist racial capitalism and environmental racism as interlocking and mutually generative systems (Heynen in Abolit A J Insurg Polit 1:240–247, 2018a; Pulido in Prog Hum Geogr 41:524–533, 2017). Green criminology is a field well-placed to explore such radical possibilities (Bradshaw in Crit Criminol 26:407–422, 2018). This paper offers a green criminological rejoinder to the bourgeoning project of ‘abolition ecology’. The paper works to bring together these linked perspectives, asking how green criminology might contribute to abolition ecology. The paper outlines its abolitionist theoretical framework, and then identifies some benefits of a green criminological orientation. It goes on to suggest three possible points of unity between green criminology and abolition ecology. In embracing these points of unity, and abolitionist principles more broadly, green criminology can better work towards more racially and ecologically just futures.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
Cartographical representations (maps, charters and plans) are taken as didactic resources in Geography classes in the 5th grade of the municipal public schools in S?o Jos? de Ribamar through a methodological approach taking into consideration the use of those resources is still worries an important part of the teachers of the Maranh?o State public schools who teach in this level. Papers related to the theme, most of the time, are non accessible to the teachers of the maranhense public schools, mainly because the education instilutions, which use those resources, do it in a very incipient way. So this research proposes from the drawings of magnetccoursein the school courtyards, together with maps, charts, plans among others representation used in the classroom environment, motivate the students to a deeper interests in participating in Geography learning process in the 5th grade. Interviews, analyses of socialcultural questionnaires of the families involved in the process; observations of classes, trainings, geocartographical orientations, application of pre and posttests, discussions about the usage of cartographic representations, proposed and effectivated tasks in the classroom, as well as around the school, were the basis of the researched population. As a result of this process, it was produced a was complement didatical material showing, among others, the space in which students, for sure, will contribute in an effective way to a better teaching practice in the chain of maranhense public schools, having in mind that these geographic subjects may be taught in the level we focused our study
Abordase o uso das representa??es cartogr?ficas (mapas, cartas e plantas) como recursos did?ticos nas aulas de Geografia na 5? s?rie da rede p?blica municipal de S?o Jos? de Ribamar, a partir de uma proposta metodol?gica, onde, o uso desses recursos ainda ? motivo de preocupa??o para uma parcela consider?vel de educadores que ministram aulas no ensino fundamental. Trabalhos a respeito do tema, na maioria das vezes, s?o inacess?veis aos professores da rede p?blica maranhense, principalmente tendo em vista que as institui??es de ensino que fazem uso desse recurso, ainda o fazem de forma incipiente. Assim sendo, a pesquisa prop?e, a partir do desenho derumosmagn?ticosnos p?tios escolares, em conjunto com mapas, cartas, plantas, entre outras representa??es utilizadas na sala de aula, despertar em educandos, um maior interesse em participar do processo de aprendizagem nas aulas de Geografia da 5? s?rie. Entrevistas; an?lises de question?rios s?cioculturais das fam?lias envolvidas no processo; observa??o de aulas; treinamentos; orienta??es geocartogr?ficas; aplica??o de pr? e p?stestes, discuss?es a respeito do uso de representa??es cartogr?ficas, tarefas propostas e efetivadas nas salas de aulas e em torno das escolas, embasaram e envolveram todo o universo amostral pesquisado. Como resultante desse processo, foi produzido material did?tico complementar retratando o espa?o vivenciado pelos educandos, que, certamente, contribuir?, de forma efetiva, para a melhoria da pr?tica docente nas escolas da rede p?blica maranhense, na medida em que os conte?dos geogr?ficos da referida s?rie forem ministrados