The rehabilitation of a Victorian clay brick railway viaduct

Larpool viaduct is a 13 span clay brick viaduct built between 1882 and 1884 to carry the Scarborough and Whitby railway across the picturesque Esk Valley in Whitby, North Yorkshire, England. The structure is of multi-ring clay brick arch construction supported on solid brickwork piers founded on mass concrete or concrete filled brickwork caissons. The railway was closed to rail traffic in 1965 but was re-opened to pedestrian and cycle traffic in 2000; it is now part of a regional sustainable transport network used mainly by tourists. Exposure to wind, driving rain and repeated freeze-thaw cycles has resulted in severe spalling of some of the brickwork, particularly that from the 30m high piers. This paper describes the original construction, the rehabilitation works including the historical context of the structure, site inspections prior to and during construction and a review of the rehabilitation works taking into account factors such as differential movement and the need to achieve a high standard of workmanship

The rehabilitation of short span masonry arch highway bridges using near-surface reinforcement

Near-surface reinforcement has been developed as a minimum intervention, minimum disruption repair or strengthening technique for masonry arch bridges and similar structures. It involves installing small diameter stainless steel reinforcing bars, typically 6mm to 12mm in diameter, into pre-cut grooves or pre-drilled holes in the near-surface zones of the bridge that are likely to be subject to tensile stress. The principal aims of adding reinforcement are to improve flexural crack control, increase flexural and shear strength and to increase robustness and ductility. Typically the reinforcement is installed in the readily accessible surfaces, i.e. the intrados (or soffit) of the arch barrel and the exposed faces of the piers, abutments, spandrels, parapets and wingwalls. This paper summarises the results of a series of tests carried out on 2.95m span clay brick arches in the laboratory. The results of the research were used when designing the strengthening works for a single span arch bridge constructed in the late 18th century to span the Kennet and Avon Canal at Hungerford in Southern England. An innovative feature of this project, which is also briefly described in the paper, is that the longitudinal steel reinforcement was installed in holes that were pre-drilled into the soffit of the arch barrel to follow the line of the arch using a directed drilling technique. The strengthening scheme was given an Historic Bridge and Infrastructure Award by the Institution of Civil Engineers

Group additive modeling of substituent effects in monocyclic aromatic hydrocarbon radicals

The thermodynamic properties of the unsubstituted and substituted phenyl, phenoxy, anisyl, benzoyl, styryl and benzyl radicals with six substituents (hydroxy, methoxy, formyl, vinyl, methyl, and ethyl) are calculated with the bond additivity corrected (BAC) post-Hartree-Fock G4 method. Bond dissociation energies of monocyclic aromatic hydrocarbons are calculated and used to identify substituent interactions in these radicals. Benson's Group Additivity (GA) scheme is extended to aromatic radicals by defining 6 GAV and 29 NNI parameters through least squares regression to a database of thermodynamic properties of 369 radicals. Comparison between G4/BAC and GA calculated thermodynamic values shows that the standard enthalpies of formation generally agree within 4 kJ mol−1, whereas the entropies and the heat capacities deviate less than 4 J mol−1 K−1

A curve shortening flow rule for closed embedded plane curves with a prescribed rate of change in enclosed area

Motivated by a problem from fluid mechanics, we consider a generalization of the standard curve shortening flow problem for a closed embedded plane curve such that the area enclosed by the curve is forced to decrease at a prescribed rate. Using formal asymptotic and numerical techniques, we derive possible extinction shapes as the curve contracts to a point, dependent on the rate of decreasing area; we find there is a wider class of extinction shapes than for standard curve shortening, for which initially simple closed curves are always asymptotically circular. We also provide numerical evidence that self-intersection is possible for non-convex initial conditions, distinguishing between pinch-off and coalescence of the curve interior

Significant Miocene larger foraminifera from South Central Java

The Gunung Sewu area of South Central Java, Indonesia during Mid Miocene, Langhian-Serravallian (Tf1-Tf2), was deposited in a large area of warm, very shallow-marine water. Coralline algae and abundant larger benthic foraminifera dominate the carbonate lithologies. Larger benthic foraminifera from previously unstudied sections in South Central Java are described and figured. They have led to an understanding of sequence stratigraphic and facies relationship of Miocene carbonates in Indonesia. Thirteen larger foraminifera species are described and illustrated. A detailed biostratigraphical studies of The phylogeny Katacycloclypeus annulatus - K. martini and the gradual evolution from Austrotrillina asmariensis into A. howchini are recognised. Analysis of the larger benthic foraminifera has allowed accurate dating of the carbonate sections studied using the East Indian Letter Classification

An experimental investigation of retro-reinforced clay brick arches

This paper describes the laboratory testing of eight 2.95m span segmental profile clay brick arches. Seven of the arches were strengthened with longitudinal intrados (soffit) reinforcement; the eighth was left unreinforced as an experimental control. Three of the arches also contained reinforcement to resist inter-ring shear. The barrel of each arch consisted of 3 rings of brickwork laid in stretcher bond; the compressive strength of the mortar used in the arch construction varied from 1.7 to 6.2 MPa. In each case a full width line load was applied incrementally to the arch extrados at quarter span until collapse occurred. Surface crack development and the vertical deflection profile of each arch were recorded at each load increment. In all cases, the longitudinal reinforcement was found to delay the onset of cracking and to increase the load carrying capacity. As expected, premature failure by ring separation was found to occur in the arches constructed with the weakest mortar without inter-ring reinforcement. Radial dowels were found to be the most effective means of preventing ring separation. The effect of the longitudinal reinforcement was found to be greatest in the arches where measures were taken to prevent ring separation

A heuristic model of bounded route choice in urban areas

There is substantial evidence to indicate that route choice in urban areas is complex cognitive process, conducted under uncertainty and formed on partial perspectives. Yet, conventional route choice models continue make simplistic assumptions around the nature of human cognitive ability, memory and preference. In this paper, a novel framework for route choice in urban areas is introduced, aiming to more accurately reflect the uncertain, bounded nature of route choice decision making. Two main advances are introduced. The first involves the definition of a hierarchical model of space representing the relationship between urban features and human cognition, combining findings from both the extensive previous literature on spatial cognition and a large route choice dataset. The second advance involves the development of heuristic rules for route choice decisions, building upon the hierarchical model of urban space. The heuristics describe the process by which quick, 'good enough' decisions are made when individuals are faced with uncertainty. This element of the model is once more constructed and parameterised according to findings from prior research and the trends identified within a large routing dataset. The paper outlines the implementation of the framework within a real-world context, validating the results against observed behaviours. Conclusions are offered as to the extension and improvement of this approach, outlining its potential as an alternative to other route choice modelling frameworks

NGOs, Turnout, and the Left: A Sub-national Analysis of Brazil

This article is designed to examine the role non-governmental organizations (NGOs) play in politics. Previous evidence suggests that NGOs mobilize communities to challenge existing patterns of authority or that they serve hand in glove with existing elites. We reconcile these two contradictory findings by identifying an important contextual feature that helps determine the extent NGOs mobilize or anesthetize. We argue that a community’s level of education influences not only whether people vote but how they vote. We employ a cross-sectional data set from Brazilian municipalities that allows us to estimate the relationship between NGOs, voting turnout, and electoral results. We find that although there is a significant statistical interaction between literacy and NGOs when explaining voting turnout, the effect is not substantively important. The interaction between literacy and NGOs is, however, an important consideration in determining how people vote: in communities with relatively low literacy rates, a robust NGO presence significantly increases the left’s electoral fortunes. Our findings imply the influence NGOs have on society is more political than social

Patient enablement requires physician empathy: a cross-sectional study of general practice consultations in areas of high and low socioeconomic deprivation in Scotland

<b>Background</b> Patient 'enablement' is a term closely aligned with 'empowerment' and its measurement in a general practice consultation has been operationalised in the widely used patient enablement instrument (PEI), a patient-rated measure of consultation outcome. However, there is limited knowledge regarding the factors that influence enablement, particularly the effect of socio-economic deprivation. The aim of the study is to assess the factors influencing patient enablement in GP consultations in areas of high and low deprivation.<p></p> <b>Methods</b> A questionnaire study was carried out on 3,044 patients attending 26 GPs (16 in areas of high socio-economic deprivation and 10 in low deprivation areas, in the west of Scotland). Patient expectation (confidence that the doctor would be able to help) was recorded prior to the consultation. PEI, GP empathy (measured by the CARE Measure), and a range of other measures and variables were recorded after the consultation. Data analysis employed multi-level modelling and multivariate analyses with the PEI as the dependant variable.<p></p> <b>Results</b> Although numerous variables showed a univariate association with patient enablement, only four factors were independently predictive after multilevel multivariate analysis; patients with multimorbidity of 3 or more long-term conditions (reflecting poor chronic general health), and those consulting about a long-standing problem had reduced enablement scores in both affluent and deprived areas. In deprived areas, emotional distress (GHQ-caseness) had an additional negative effect on enablement. Perceived GP empathy had a positive effect on enablement in both affluent and deprived areas. Maximal patient enablement was never found with low empathy.<p></p> <b>Conclusions</b> Although other factors influence patient enablement, the patients' perceptions of the doctors' empathy is of key importance in patient enablement in general practice consultations in both high and low deprivation settings

Measurement and Particle Statistics in the Szilard Engine

A Szilard Engine is a hypothetical device which is able to extract work from a single thermal reservoir by measuring the position of particles within the engine. We derive the amount of work that can be extracted from such a device in the low temperature limit. Interestingly, we show this work is determined by the information gain of the initial measurement rather than by the number and type of particles which constitute the working substance. Our work provides another clear connection between information gain and extractable work in thermodynamical processes.Comment: 4 page