64 resultados para Pontoon-bridges, Military.


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Little research has examined the impact of being an accompanying spouse on British military foreign postings. The aim of this qualitative study was to investigate the experiences of 13 military spouses from 11 different overseas locations. Data were collected via an online forum and thematic content analysis was conducted. Key findings revealed that, regardless of the location, reactions to overseas posting varied considerably and were related to the military spouse's personality and personal circumstances, as well as their relationship with family, husband and their support networks. Spouses experienced a loss of control over their lives that was in some cases psychologically distressing. The findings corroborate and extend the findings from a previous study that was limited to one location, further highlighting the need for pre-established support resources from the military and healthcare professionals to be readily accessible for all military spouses. Importantly, such support provision may also facilitate the military spouse in regaining some control over their everyday life, enhancing their well-being and the experience for the family.

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As part of an ethnographic study, the impact of foreign postings on spouses who accompany military personnel was explored. Individual interviews and focus groups with 34 British military spouses based in one location in southern Europe were conducted. Key findings suggested that reaction to a foreign posting was a reflection of personal attitudes, prior experiences, support, ability to adjust to change and strength of relationship with the serving spouse and community. For many the experience was positive due to the increased opportunity for family time, for others this helped to compensate for the difficulties experienced. Some military spouses experienced significant distress on the posting, particularly if the family was not well-supported. The potential implications of military spouses not adapting to foreign postings have significant implications for healthcare practice. Provision of more appropriate support resources before and during the posting would facilitate the transition for the military spouse and their family.

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This study discusses structural damage diagnosis of real steel truss bridges by measuring trafficinduced vibration of bridges and utilizing a damage indicator derived from linear system parameters of a time series model. On-site damage experiments were carried out on real steel truss bridges. Artificial damage was applied to the bridge by severing a truss member with a cutting machine.Vehicle-induced vibrations of the bridges before and after applying damagewere measured and used in structural damage diagnosis of the bridges. Changes in the damage indicator are detected by Mahalanobis-Taguchi system (MTS) which is one of multivariate outlier analyses. The damage indicator and outlier detection was successfully applied to detect anomalies in the steel truss bridges utilizing vehicle-induced vibrations. Observations through this study demonstrate feasibility of the proposed approach for real world applications.

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As a consequence of climate change there is now a more frequent occurrence of extreme rainfall events where, with higher rates of urbanisation, the built environment has become increasingly affected by flooding.. This is of particular importance in relation to the stability of bridge structures that span rivers and canals etc. In November 2009, the UK and Ireland were subjected to extraordinarily severe weather conditions for several days. The rainfall was logged as the highest level of rainfall ever recorded within the UK, and as a direct consequence, unprecedented flooding occurred in Cumbria. This flooding led to the collapse of three road bridges which were generally 19th century masonry arch bridges, with relatively shallow foundations. In the UK, knowledge of the combined effect of bridge scouring and inundation has been not been particularly widely studied. Research carried out by Hamill et al [1] considered the hydraulic analysis of single arch bridges under flood conditions, but no consideration was given towards the likely damage to these structures due to scouring. Prior to this, Bierry and Delleur [2] produced a classic paper in predicting the discharge downstream of an inundated arch, focussing on predicting afflux as opposed to bridge scour. Further work on backwater effects was carried out by Martin-Vide & Prio [3] in semi-circular arch bridges. Both pressurized and free-surface flows at the bridge were investigated. Flows on a mobile bed in clear-water conditions were compared to those with a rigid bed, but no predictive equation for scour under pressurised conditions was considered. This paper will present initial findings from an experimental investigation into the effects of surcharged flow and subsequent scour within the vicinity of single span arch bridges. Velocities profiles will be shown within the vicinity of the arch, in addition to the depth of clear water scour, for a series of flows and model spans. The data will be presented, where results will be correlated to the most recent predictive equations that are proposed.

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As a consequence of increased levels of flooding, largely attributable to urbanization of watersheds (and perhaps climate change, more frequent extreme rainfall events are occurring and threatening existing critical infrastructure. Many of which are short-span bridges over relatively small waterways (e.g., small rivers, streams and canals). Whilst these short-span bridges were designed, often many years ago, to pass relatively minor the then standard return-period floods, in recenttimes the failure incidence of such short-span bridges has been noticeably increasing. This is suggestive of insufficient hydraulic capacity or alternative failure mechanism not envisaged at the time of design e.g. foundation scour or undermining. This paper presen ts, and draws lessons, from bridge failures in Ireland and the USA. For example, in November 2009, the UK and Ireland were subjected to extraordinarily severe weather conditions for several days. The resulting flooding led to the collapse of three UK bridges that were generally 19th century masonry arch bridges, withrelatively shallow foundations. Parallel failure events have been observed in the USA. To date, knowledge of the combined effect of waterway erosion, bridge submergence, and geotechnical collapse has not been adequately studied. Recent research carried out considered the hydraulic analysis of short span bridges under flood conditions, but no consideration was given towards the likely damage to these structures due to erosive coupling of hydraulic and geotechnical factors. Some work has been done to predict the discharge downstream of an inundated arch, focusing onpredicting afflux, as opposed to bridge scour, under both pressurized and free-surface flows, but no ! predictive equation for scour under pressurized conditions was ever considered. The case studies this paper presents will be augmented by the initial findings from the laboratory experiments investigating the effects of surcharged flow and subsequent scour within the vicinity of single span arch bridges. Velocities profiles will be shown within the vicinity of the arch, in addition to the depth of consequent scour, for a series of flows and model spans. The data will be presented and correlated to the most recent predictive equations for submerged contraction and abutment scour. The accuracy of these equations is examined, and the findings used as a basis for developing further studies in relation to short span bridges.

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Externally bonding of FRP composites is an effective technique for retrofitting historical masonry arch structures. A major failure mode in such strengthened structures is the debonding of FRP from the masonry. The bond behaviour between FRP and masonry thus plays a crucial role in these structures. Major challenges exist in the finite element modelling of such structures, such as modelling of mixed Mode-I and Mode-II bond behaviour between the FRP and the curved masonry substrate, modelling of existing damages in the masonry arches, consideration of loading history in the unstrengthened and strengthened structure etc. This paper presents a rigorous FE model for simulating FRP strengthened masonry arch structures. A detailed solid model was developed for simulating the masonry and a mixed-mode interface model was used for simulating the FRP-to-masonry bond behaviour. The model produces results in very close agreement with test results.

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This paper presents a multimodal analysis of online self-representations of the Elite Squad of the military police of Rio de Janeiro, the Special Police Operations Battalion BOPE. The analysis is placed within the wider context of a “new military urbanism”, which is evidenced in the ongoing “Pacification” of many of the city’s favelas, in which BOPE plays an active interventionist as well as a symbolic role, and is a kind of solution which clearly fails to address the root causes of violence which lie in poverty and social inequality. The paper first provides a sociocultural account of BOPE’s role in Rio’s public security and then looks at some of the mainly visual mediated discourses the Squad employs in constructing a public image of itself as a modern and efficient, yet at the same time “magical” police force.

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Bridge construction responds to the need for environmentally friendly design of motorways and facilitates the passage through sensitive natural areas and the bypassing of urban areas. However, according to numerous research studies, bridge construction presents substantial budget overruns. Therefore, it is necessary early in the planning process for the decision makers to have reliable estimates of the final cost based on previously constructed projects. At the same time, the current European financial crisis reduces the available capital for investments and financial institutions are even less willing to finance transportation infrastructure. Consequently, it is even more necessary today to estimate the budget of high-cost construction projects -such as road bridges- with reasonable accuracy, in order for the state funds to be invested with lower risk and the projects to be designed with the highest possible efficiency. In this paper, a Bill-of-Quantities (BoQ) estimation tool for road bridges is developed in order to support the decisions made at the preliminary planning and design stages of highways. Specifically, a Feed-Forward Artificial Neural Network (ANN) with a hidden layer of 10 neurons is trained to predict the superstructure material quantities (concrete, pre-stressed steel and reinforcing steel) using the width of the deck, the adjusted length of span or cantilever and the type of the bridge as input variables. The training dataset includes actual data from 68 recently constructed concrete motorway bridges in Greece. According to the relevant metrics, the developed model captures very well the complex interrelations in the dataset and demonstrates strong generalisation capability. Furthermore, it outperforms the linear regression models developed for the same dataset. Therefore, the proposed cost estimation model stands as a useful and reliable tool for the construction industry as it enables planners to reach informed decisions for technical and economic planning of concrete bridge projects from their early implementation stages.

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It seems unlikely that Moscow can hope for an outright victory in Syria’s civil war, so some kind of political compromise with the moderate opposition is in the offing. This, however, is at best a long shot given the hostility to Assad in the West and the intensity of the conflict in Syria.

Instead, the immediate priority seems to be to ensure a survival of the Syrian state and military institutions in the areas it can control, what one Russian observer called an “Alawite Israel” – a strip of land from the Mediterranean coast to Damascus, able to at least contain IS with some external support.

The Kremlin has consistently prioritised stability over revolutionary change and sovereign rights over humanitarian intervention. In fact, from the Russian point of view, the Western interventionist agenda of democratisation, which ignored local conditions, has made the situation in the Middle East worse – from Iraq to Libya and Syria.

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Bridge structures are subject to continuous degradation due to the environment, ageing and excess loading. Monitoring of bridges is a key part of any maintenance strategy as it can give early warning if a bridge is becoming unsafe. This paper will theoretically assess the ability of a vehicle fitted with accelerometers on its axles to detect changes in damping of bridges, which may be the result of damage. Two vehicle models are used in this investigation. The first is a two degree-of-freedom quarter-car and the second is a four degree-of-freedom halfcar. The bridge is modelled as a simply supported beam and the interaction between the vehicle and the bridge is a coupled dynamic interaction algorithm. Both smooth and rough road profiles are used in the simulation and results indicate that changes in bridge damping can be detected by the vehicle models for a range of vehicle velocities and bridge spans.

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This paper describes a ‘drive-by’ method of bridge inspection using an instrumented vehicle. Accelerometers on the vehicle are proposed as a means of detecting damage on the bridge in the time it takes for the vehicle to cross the bridge at full highway speed. For a perfectly smooth road profile, the method is shown to be feasible. Changes in bridge damping, which is an indicator of damage, are clearly visible in the acceleration signal of a quarter-car vehicle on a smooth road surface modelled using MatLab. When road profile is considered, the influence of changes in bridge damping on the vehicle acceleration signal is much less clear. However, when a half-car model is used on a road with a rough profile, it is again possible to detect changes in bridge damping, provided the vehicle has two identical axles.

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This chapter uses the newly released Military Service Pensions files to examine the contribution of Rosana 'Rosie' Hackett and the members of the Irish Citizen Army to the Irish revolution. It also includes and assessment of the collection as a source for studying the revolution and assesses how it helps reassess the role of the ICA in the revolution. It was produced to mark the naming of a Liffey bridge in Dublin after Rosie Hackett