The University of Southampton
University of Southampton Institutional Repository

Numerical modelling of lateral stress on integral abutments due to cyclic loading

Numerical modelling of lateral stress on integral abutments due to cyclic loading
Numerical modelling of lateral stress on integral abutments due to cyclic loading
The integral bridge concept eliminates problems associated with expansion joints and bearings used on conventional bridges. However, integral structures are not free from problems, and of particular concern is the magnitude of lateral soil stress which acts on the abutments. The cyclic nature of abutment displacement, caused by thermal loading of the deck, results in increased lateral soil stress from the granular backfill. Previous experiments investigated the fundamental behaviour of a granular soil element under integral bridge loading. No existing constitutive soil model replicated this behaviour, and therefore a soil model has been developed based upon this data. It was designed to account for the changes in secant stiffness and vertical strain due to the density and rolling/sliding behaviour of soil particles at the active state, found to be important in the previous research. The model was implemented into a finite difference method program, and initially validated by modelling the experimental triaxial tests. Subsequent modelling of centrifuge tests of bridge abutments, carried out by independent researchers, allowed the soil model to be validated at system level. After validation and testing, the model was considered suitable for predicting the lateral stress profile acting on integral bridge abutments and used in a parametric study. This highlighted that the value of wall friction coefficient is particularly significant in the system behaviour. The centrifuge test is an idealised system where only rotation/flexure is possible, so a spread base abutment was modelled to investigate the predicted stress profile for an in-service bridge. These were shown to be significantly different to those prescribed by BA42/96, both in shape and magnitude. Additionally, modelling daily cycles results in a different profile to yearly cycles. This research has shown that the soil model developed can provide good estimates of lateral soil stress. This can be used to further investigate soil loads acting on integral bridge abutments with the aim of improving the design of such structures.
Banks, J.R
28f25206-ac70-4426-9bd7-acf1a6422123
Banks, J.R
28f25206-ac70-4426-9bd7-acf1a6422123
Bloodworth, A.G.
08ac0375-0691-41d4-937d-d7d643dc8ddb

Banks, J.R (2009) Numerical modelling of lateral stress on integral abutments due to cyclic loading. University of Southampton, Faculty of Engineeering and the Environment, Doctoral Thesis, 292pp.

Record type: Thesis (Doctoral)

Abstract

The integral bridge concept eliminates problems associated with expansion joints and bearings used on conventional bridges. However, integral structures are not free from problems, and of particular concern is the magnitude of lateral soil stress which acts on the abutments. The cyclic nature of abutment displacement, caused by thermal loading of the deck, results in increased lateral soil stress from the granular backfill. Previous experiments investigated the fundamental behaviour of a granular soil element under integral bridge loading. No existing constitutive soil model replicated this behaviour, and therefore a soil model has been developed based upon this data. It was designed to account for the changes in secant stiffness and vertical strain due to the density and rolling/sliding behaviour of soil particles at the active state, found to be important in the previous research. The model was implemented into a finite difference method program, and initially validated by modelling the experimental triaxial tests. Subsequent modelling of centrifuge tests of bridge abutments, carried out by independent researchers, allowed the soil model to be validated at system level. After validation and testing, the model was considered suitable for predicting the lateral stress profile acting on integral bridge abutments and used in a parametric study. This highlighted that the value of wall friction coefficient is particularly significant in the system behaviour. The centrifuge test is an idealised system where only rotation/flexure is possible, so a spread base abutment was modelled to investigate the predicted stress profile for an in-service bridge. These were shown to be significantly different to those prescribed by BA42/96, both in shape and magnitude. Additionally, modelling daily cycles results in a different profile to yearly cycles. This research has shown that the soil model developed can provide good estimates of lateral soil stress. This can be used to further investigate soil loads acting on integral bridge abutments with the aim of improving the design of such structures.

Text
__soton.ac.uk_ude_PersonalFiles_Users_slb1_mydocuments___soton.ac.uk_ude_PersonalFiles_Users_slb1_mydocuments_J._Banks_Thesis_-_June_2009.pdf - Other
Download (2MB)

More information

Published date: 1 June 2009
Organisations: University of Southampton, Faculty of Engineering and the Environment

Identifiers

Local EPrints ID: 210943
URI: http://eprints.soton.ac.uk/id/eprint/210943
PURE UUID: 3efbba7c-3466-4ff6-babd-a9931406f5a5

Catalogue record

Date deposited: 01 Jul 2013 10:46
Last modified: 14 Mar 2024 04:51

Export record

Contributors

Author: J.R Banks
Thesis advisor: A.G. Bloodworth

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×