Open Access. Powered by Scholars. Published by Universities.®

Structural Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Technological University Dublin

Discipline
Keyword
Publication Year
Publication
File Type

Articles 91 - 105 of 105

Full-Text Articles in Structural Engineering

Modeling Extreme Traffic Loading On Bridges Using Kernel Density Estimators, Cathal Leahy, Eugene J. Obrien, Bernard Enright Jan 2011

Modeling Extreme Traffic Loading On Bridges Using Kernel Density Estimators, Cathal Leahy, Eugene J. Obrien, Bernard Enright

Conference papers

Kernel density estimators are a non-parametric method of estimating the probability density function of sample data. In this paper, the method is applied to find characteristic maximum daily truck weights on highway bridges. The results are then compared with the conventional approach


Input-Output Analysis Of Irish Construction Sector Greenhouse Gas Emissions, Adolf Acquaye, Aidan Duffy Apr 2010

Input-Output Analysis Of Irish Construction Sector Greenhouse Gas Emissions, Adolf Acquaye, Aidan Duffy

Articles

Ireland is committed to limiting its greenhouse gas (GHG) emissions to 113% of 1990 levels over the period 2008-12 and to 84% of 2005 levels by 2020 under the Kyoto Agreement and the EU’s ’20 20’ by 2020 respectively. National policies have targeted many industry sectors but have failed to directly tackle GHG emissions associated with construction activity. This paper estimates energy and GHG emissions intensities of the Irish construction sector and subsectors and estimates its contribution to Irish national emissions. This information is used to identify and assess the impacts of policy measures which would result in a reduction …


Simulation Of Traffic Loading On Highway Bridges, Bernard Enright Mar 2010

Simulation Of Traffic Loading On Highway Bridges, Bernard Enright

Other resources

This work is based on weigh-in-motion measurements for approximately three million trucks obtained from sites in five European countries. Techniques have been developed, supported by photographic evidence, for filtering the measurements to identify and remove unreliable values, and for the classification of extremely heavy vehicles. The collected measurements have been used as the basis for building and calibrating a Monte Carlo simulation model for bridge loading. Two-lane traffic is simulated – either two lanes in the same direction or one lane in each direction. The model allows for vehicles that are both heavier and have more axles than in the …


Site Specific Modelling Of Traffic Loading On Highway Bridges, Bernard Enright, Eugene J. Obrien Jan 2010

Site Specific Modelling Of Traffic Loading On Highway Bridges, Bernard Enright, Eugene J. Obrien

Conference papers

Accurate traffic loading models based on measured weigh-in-motion (WIM) data are essential for the accurate assessment of existing bridges. Much work has been published on the Monte Carlo simulation of single lanes of heavy vehicle traffic, and this can easily be extended to model the loading on bridges with two streams of traffic in opposing directions. However, a typical highway bridge will have multiple lanes in the same direction, and various types of correlation are evident in measured traffic, such as groups of very heavy vehicles travelling together and heavy vehicles being overtaken by lighter ones. These traffic patterns affect …


Characteristic Dynamic Increment For Extreme Traffic Loading Events On Short And Medium Span Highway Bridges, Eugene J. Obrien, Daniel Cantero, Bernard Enright, Arturo González Jan 2010

Characteristic Dynamic Increment For Extreme Traffic Loading Events On Short And Medium Span Highway Bridges, Eugene J. Obrien, Daniel Cantero, Bernard Enright, Arturo González

Articles

More accurate assessment of safety can prevent unnecessary repair or replacement of existing bridges which in turn can result in great cost savings at network level. The allowance for dynamics is a significant component of traffic loading in many bridges and is often unnecessarily conservative. Critical traffic loading scenarios are considered in this paper with a model that allows for vehicle-bridge interaction and takes into account the road surface condition. Characteristic dynamic allowance values are presented for the assessment of mid-span bending moment in a wide range of short to medium span bridges for bi-directional traffic.


Importance Of The Tail In Truck Weight Modeling For Bridge Assessment, Eugene J. Obrien, Bernard Enright, Abraham Getachew Jan 2010

Importance Of The Tail In Truck Weight Modeling For Bridge Assessment, Eugene J. Obrien, Bernard Enright, Abraham Getachew

Articles

To predict characteristic extreme traffic load effects, simulations are sometimes performed of bridge loading events. To generalize the truck weight data, statistical distributions are fitted to histograms of weight measurements. This paper is based on extensive WIM measurements from two European sites and shows the sensitivity of the characteristic traffic load effects to the fitting process. A semi-parametric fitting procedure is proposed: direct use of the measured histogram where there are sufficient data for this to be reliable and parametric fitting to a statistical distribution in the tail region where there are less data. Calculated characteristic load effects are shown …


Estimating The Characteristic Vertical Response Of A Flexible Footbridge Due To Crowd Loading, Joe Keogh, Colin C. Caprani, Paul Archbold, Paul Fanning Jan 2010

Estimating The Characteristic Vertical Response Of A Flexible Footbridge Due To Crowd Loading, Joe Keogh, Colin C. Caprani, Paul Archbold, Paul Fanning

Conference papers

The issue of excessive vibration of footbridges due to pedestrian loading is now well documented. Bridge vibrations produced from a crowd of pedestrians have been estimated by modifying the effect caused by a single pedestrian by an enhancement factor to take crowd synchronization into account. In this paper this approach is extended to account for the fact that all pedestrians will not have the same pacing frequencies, and the effects of distributions of pacing frequency and other parameters on the enhancement factor are investigated. It is shown that this more faithful representation of pedestrian crowd walking behaviour gives reduced vibration …


The Influence Of Correlation On The Extreme Traffic Loading Of Bridges, Eugene J. Obrien, Bernard Enright, A. T. Dempsey Jan 2010

The Influence Of Correlation On The Extreme Traffic Loading Of Bridges, Eugene J. Obrien, Bernard Enright, A. T. Dempsey

Conference papers

Accurate traffic loading models based on measured data are essential for the accurate assessment of existing bridges. There are well-established methods for the Monte Carlo simulation of single lanes of traffic, and this can easily be extended to model the loading on bridges with two independent streams of traffic in opposing directions. However, a typical highway bridge will have multiple lanes in the same direction, and various types of correlation are evident in measured traffic. This paper analyses traffic patterns using multi-lane WIM data collected at two European sites. It describes an approach to the Monte Carlo simulation of this …


Management Strategies For Special Permit Vehicles For Bridge Loading, Bernard Enright, Eugene J. Obrien Jan 2010

Management Strategies For Special Permit Vehicles For Bridge Loading, Bernard Enright, Eugene J. Obrien

Conference papers

An examination of weigh-in-motion data collected recently at sites in five European countries has shown that vehicles with weights well in excess of the normal legal limits are found on a daily basis. These vehicles would be expected to have permits issued by the responsible authorities. It can be seen from the measurements that most of them are travelling at normal speeds. Photographic evidence indicates that, while many are accompanied by an escort vehicle, normal traffic is flowing alongside in other lanes. As European freight volume grows, the frequency of these special vehicles can be expected to increase. Hence, the …


Using Virtual Reality To Enhance Electrical Safety And Design In The Built Environment, Martin Barrett, Jonathan Blackledge, Eugene Coyle Jan 2010

Using Virtual Reality To Enhance Electrical Safety And Design In The Built Environment, Martin Barrett, Jonathan Blackledge, Eugene Coyle

Articles

Electricity and the inherent risks associated with its use in the built environment have long since been a priority for the electrical services industry and also the general public who must live and work in this environment. By its nature virtual reality has the advantage of being safe for both the user and equipment. In addition, it offers the user an opportunity to be exposed to a range of scenarios and conditions that either occur infrequently or are hazardous to replicate. This paper presents a prototype desktop virtual reality model, to enhance electrical safety and design in the built environment. …


A New Congested Traffic Load Model For Highway Bridges, Colin C. Caprani, Colm Carey, Bernard Enright Jan 2010

A New Congested Traffic Load Model For Highway Bridges, Colin C. Caprani, Colm Carey, Bernard Enright

Conference papers

Long span highway bridges are critical components of any nation’s infrastructure. Therefore accurate assessment of highway bridge loading is essential, and it is well known that congested traffic governs load effect for such bridges. Current congestion models use conservative assumptions about traffic and inter-vehicle gaps. This research investigates congested traffic flow through the use of traffic microsimulation which has the ability to reproduce complex traffic phenomena based on driver interactions. A time series model has been developed to produce a speed time-series similar to the results of the microsimulation. The speed time-series from the new model, combined with the established …


Highway Bridge Assessment For Dynamic Interaction With Critical Vehicles, Daniel Cantero, Eugene J. Obrien, Arturo González, Bernard Enright, Cillian Rowley Jan 2009

Highway Bridge Assessment For Dynamic Interaction With Critical Vehicles, Daniel Cantero, Eugene J. Obrien, Arturo González, Bernard Enright, Cillian Rowley

Conference papers

Dynamic vehicle-bridge interaction is often considered for the most common classes of vehicle such as the 5-axle articulated truck. However, the dynamic response of bridges to this type of trucks is quite different to the response to the vehicles more likely to feature in maximum-in-lifetime traffic loading events. This paper focuses on large (>100 tonne) cranes and crane-type vehicles that have been recorded at Weigh-in-Motion sites in Europe. This paper analyses the total bending moment due to these vehicles on short to medium span bridges and compare them to 5- axle articulated trucks. To account for the variability in …


Investigation Of Dynamic And Steady State Calculation Methodologies For Determination Of Building Energy Performance In The Context Of The Epbd, Mervin Dean Doyle Jul 2008

Investigation Of Dynamic And Steady State Calculation Methodologies For Determination Of Building Energy Performance In The Context Of The Epbd, Mervin Dean Doyle

Masters

The aim of this thesis was to investigate the ability of a dynamic and a quasi-steady state calculation methodology to capture the heating and cooling aspects of a buildings energy performance in the context of the requirements of the EU Energy Performance of Buildings Directive (EPBD). Chapters 1 and 2 provide a general background review and description of the implementation of the directive’s requirements in Ireland. Chapter 3 established the usefulness and relevance of building energy benchmarks, traditional approaches to building energy performance calculation methodologies. Chapter 4 established the ability of a sample of simplified and dynamic calculation tools to …


Study Of Same-Lane And Inter-Lane Gvw Correlation, Bernard Enright, Eugene J. O'Brien, Colin C. Caprani Jan 2006

Study Of Same-Lane And Inter-Lane Gvw Correlation, Bernard Enright, Eugene J. O'Brien, Colin C. Caprani

Conference papers

The methodology used is to generate a number of years of simulated traffic and to use extreme value statistics to predict more accurately the characteristic loading for a given bridge. The parameters and probability distributions used in the Monte Carlo simulation must be based on observed sample traffic data. Some previous studies have made unsubstantiated assumptions regarding correlation between the Gross Vehicle Weights (GVW) of trucks in the same lane, or between trucks in adjacent, same-direction lanes. For this paper, an extensive database of Dutch Weigh-in-Motion data is analysed. Data are collected from two same-direction lanes and are time-stamped to …


Finite Element Modelling Of Moisture Movement In Concrete Floors, Niall Holmes, Roger West Sep 2003

Finite Element Modelling Of Moisture Movement In Concrete Floors, Niall Holmes, Roger West

Conference papers

Predictive methods for determining the point at which it is safe to apply floor coverings to concrete floors can save time and money for the client, contractor and the floor installer. The current standard states that impervious floor coverings should not be applied until the surface of the floor reaches a relative humidity (RH) of 75%, established using a surface hygrometer test. Tests at Trinity College Dublin on drying concrete slabs in natural and forced drying environments show that there is a large variation in the residue of moisture deep in the concrete when the floor covering is applied, particularly …