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Znidaric A.,Slovenian National Building And Civil Engineering Institute | Pakrashi V.,Roughan ODonovan Consulting Engineers | O'Brien E.,University College Dublin | O'Connor A.,Trinity College Dublin
Proceedings of the Institution of Civil Engineers: Urban Design and Planning

The European Union has expanded significantly in recent years. Sustainable trade within the Union, leading to economic growth to the benefit of the 'old' and 'new' member states is thus extremely important. The road infrastructure is strategic and vital to such development since an uneven transport infrastructure, in terms of capacity and condition, has the potential to reinforce uneven development trends and hinder economic convergence of old and new member states. In the decades since their design and construction, loading conditions have significantly changed for many major highway infrastructure elements/networks owing primarily to increased freight volumes and vehicle sizes. This, coupled with the gradual deterioration of a significant number of highway structures due to their age, and the absence of a pan-European assessment framework, can be expected to affect the smooth functioning of the infrastructure in its as-built condition. Increased periods of reduced flow can be expected owing to planned and unplanned interventions for repair/rehabilitation. This paper reports the findings of a survey regarding the current status of the highway infrastructure elements in six countries within the European Union as reported by the owners/ operators. The countries surveyed include a cross-section of 'existing' older countries and 'new' member states. The current situations for bridges, culverts, tunnels and retaining walls are reported, along with their potential replacement costs. The findings act as a departure point for further studies in support of a centralised and/or synchronised EU approach to infrastructure maintenance management. Information in the form presented in this paper is central to any future decision-making frameworks in terms of trade route choice and operations, monetary investment, optimised maintenance, management and rehabilitation of the built infrastructure and the economic integration of the newly joined member states. Source

Pakrashi V.,University College Cork | Harkin J.,Queens University of Belfast | Kelly J.,Roughan ODonovan Consulting Engineers | Farrell A.,National Roads Design Office | Nanukuttan S.,Queens University of Belfast
Proceedings of the Institution of Civil Engineers: Bridge Engineering

This paper details the monitoring and repair of an impact damaged prestressed concrete bridge. The repair was required following an impact from a low-loader carrying an excavator while passing underneath the bridge. The repair was carried out by preloading the bridge in the vicinity of the damage to relieve some prestressing. This preload was removed following the hardening and considerable strength gain of the repair material. The true behaviour of damaged prestressed concrete bridges during repair is difficult to estimate theoretically due to a lack of benchmarking and inadequacy of assumed damage models. A network of strain gauges at locations of interest was thus installed during the entire period of repair. Effects of various activities were qualitatively and quantitatively observed. The interaction and rapid, model-free calibration of damaged and undamaged beams, including identification of damaged gauges, were also probed. This full-scale experiment is expected to be of interest and benefit to the practising engineer and the researcher alike. Source

Choine M.N.,Roughan ODonovan Consulting Engineers | Kashani M.M.,University of Bristol | Lowes L.N.,University of Washington | O'Connor A.,Trinity College Dublin | And 3 more authors.
International Journal of Structural Integrity

Purpose - The purpose of this paper is to explore the impact of corrosion of reinforcing steelin RC columns on the seismic performance of a multi-span concrete integral bridge. A new constitutive model for corroded reinforcing steel is used. This model simulates the buckling of longitudinal reinforcement under cyclic loading and the impact of corrosion on buckling strength. Cover concrete strength is adjusted to account for corrosion induced damage and core concrete strength and ductility is adjusted to account for corrosion induced damage to transverse reinforcement. This study evaluates the impact which chloride induced corrosion of the reinforced concrete columns on the seismic fragility of the bridge. Fragility curves are developed at a various time intervals over the lifetime. The results of this study show that the bridge fragility increases significantly with corrosion. Design/methodology/approach - This paper first, evaluates the impact which chloride induced corrosion of the columns has on bridge fragility. Finally, fragility curves are developed at various time intervals over the lifetime of the bridge. The results of this study show that the bridge fragility increases significantly with corrosion. Findings - First, it was found that columns dominate the system fragility at all levels of deterioration. Therefore, it highlights the importance of good column design in terms of both seismic detailing and durability for this integral bridge type. Second, in terms of foundation settlement coupled with corrosion, it was found that settlements on the order of the discrete levels,adopted for this study increased the system fragility at the slight, moderate and extensive damage states but their impact at the complete damage states is negligible. Third, ageing considerations are currently neglected in widespread regional risk assessment and loss estimation packages for transport infrastructure. The result of this study provides a methodology that enables bridge managers and owners to employ in seismic risk assessment of existing aging bridges Originality/value - The modelling technician developed in this paper considers the impact of detailed corrosion damaged of RC column on nonlinear dynamic response and fragility of a corroded integral bridge under earthquake loading. The current modelling technique is the most comprehensive 3D fibre element model for seismic analysis and risk assessment of corroded bridges. Source

McCabe B.A.,National University of Ireland | Sheil B.B.,National University of Ireland | Long M.M.,University College Dublin | Buggy F.J.,Roughan ODonovan Consulting Engineers | Farrell E.R.,AGL Consulting Geotechnical Engineers
Proceedings of the Institution of Civil Engineers: Geotechnical Engineering

Numerous correlations have been developed in the literature relating the compression index Cc of soft soils to simple index properties that serve as a useful reality check on oedometer test results. However, many of these empirical correlations are specific to soils of a certain geographic region and/or geological origin and therefore may not be applicable in other contexts. Compression index data and corresponding index properties, specific to a good geographic spread of Irish soft soil sites, have been compiled in this paper. Of all the forms of correlation considered, the relationship between compression ratio Cc and the natural water content is the most fruitful in terms of allowing preliminary predictions of compression index to be made. © 2014, Thomas Telford Services Ltd. All rights reserved. Source

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