Influence of the Accuracy of a Bridge Weigh-In-Motion System on the Determination of a Bridge Assess...
Sponsored Links
This presentation is the property of its rightful owner.
1 / 21

Jason Dowling Arturo González Eugene O’Brien PowerPoint PPT Presentation


  • 85 Views
  • Uploaded on
  • Presentation posted in: General

Influence of the Accuracy of a Bridge Weigh-In-Motion System on the Determination of a Bridge Assessment Dynamic Ratio. Jason Dowling Arturo González Eugene O’Brien. Quick Overview. - Bridge Weigh-In-Motion Model Description Assessment Dynamic Ratio Bridge Weigh-In-Motion Accuracy.

Download Presentation

Jason Dowling Arturo González Eugene O’Brien

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Influence of the Accuracy of a Bridge Weigh-In-Motion System on the Determination of a Bridge Assessment Dynamic Ratio

Jason Dowling

Arturo González

Eugene O’Brien


Quick Overview

  • - Bridge Weigh-In-Motion

  • Model Description

  • Assessment Dynamic Ratio

  • Bridge Weigh-In-Motion Accuracy


Bridge Weigh-In-Motion

Bridge Weigh-In-Motion systems use instrumented bridges to collect data on the truck fleet at a specific location.

  • - This concept was first proposed by Moses (1979)

  • Strain transducers are attached to the soffit of a bridge

  • Axle detectors are placed on the road surface

  • An algorithm is used to interpret the data

source: WAVE (2001)


Bridge Weigh-In-Motion

  • Moses Algorithm (1979) remains the most popular algorithm used in Bridge Weigh-In-Motion systems.

  • - Based on minimizing the sum of squares of differences between theory and measurements:

Lots of measurements are available during the truck crossing...

- This is utilised to smooth out the dynamic component.


Bridge Weigh-In-Motion

Typical ‘Measured’ Response


Bridge Weigh-In-Motion

Theoretical Response

x


Bridge Weigh-In-Motion

Matrix Solution Technique

Minimizing the Error function,

gives a system of simultaneous equations in Wi

Where {W} is a vector of the desired axle weights


Model Description

Truck Model

- 8 Degrees of Freedom


Model Description

Data Used for simulations of truck crossings...

Statistical Data for- GVW & Velocity

- Axle Spacing

- Axle Weights


Model Description

Data Used for simulations of truck crossings...

Carpet Profile


Model Description

Model Accuracy Classification

COST323 (2002) proposed a method of classification for Bridge Weigh-In-Motion systems

- The models classification under this method is ‘B+(7)’

  • Most individual axle weights predicted within ± 7%

  • Axle group weights & GVW predicted within ± 5%


Assessment Dynamic Ratio

Assessment Dynamic Ratio (ADR) is defined as:

i.e. Not necessarily associated with a single loading event

Recent work has discovered a tendency for ADR to decrease as Return Period, or Load Effect increases.


Assessment Dynamic Ratio

Trends in ADR with Time...

source: Rattigan (2007)


Assessment Dynamic Ratio

Trends in ADR with Time...

source: SAMARIS (2006)


Assessment Dynamic Ratio

Trends in ADR with Time...


Bridge Weigh-In-Motion Accuracy

Inferred Static Response


Bridge Weigh-In-Motion Accuracy

Inferred Static Response


Bridge Weigh-In-Motion Accuracy

Inferred Static Response

Error in Maximum Static


Bridge Weigh-In-Motion Accuracy

Error in prediction of ADR


In Summary:

Moses Algorithm tends to over estimate the maximum static response.

This leads to an underestimation of ADR

Future work will look at further understanding this inaccuracy

With a view to quantifying this or suggesting possible remediation measures...


My Thanks to the 6th European Framework Project ARCHES (Assessment and Rehabilitation of Central European Highway Structures) for funding my work.

Thank you for listening.


  • Login