AN INNOVATIVE APPROACH TO SMALL

BRIDGE REHABILITATION

Peter Marchant

ITS Pipetech Pty Ltd,

NSW Australia

Introduction

Summary

Since first construction our principle infrastructure we are witnessing

• Increasing traffic frequency

• Heavier loading

• Requirement for a longer working life

• Increasing demands on Design

• Ever changing Design Codes

• Less opportunity for infrastructure closures

• Need for a different approach to maintain serviceability

• Keep the infrastructure open

Alternative to New Build

• Planned Inspections

• Maintenance &

Remediation

• Think out of the Box

• Understand the

Demands on the

Structure

• Simple information

provision can save

significant cost

Conditions leading to failure

Deteriorating Arch ring material

Loss of Arch thickness

Foundation movement

Loss of Arch support

Foundation scour

Impact damage

Weak or uncompacted or over

compacted fill

Water ingress and erosion

Poor design

Simple Testing

Hammer Testing

Acoustic Emission

Radar

Thermal Imaging

Ultrasonic Testing

Loading

Considerations & Assumptions

• Consider the original methodology of construction

• Potential loss of bedding and support at the side zones and deteriorated condition

• Full or partial rehabilitation

• In the absence of physical data assume the worst and design as a stand alone element

Modelling

• Modeling using the FE analysis program i.e. Strand 7, Plaxis etc.

• Two dimensional Beam model to represent the point load test as AS/NZ3725

• Three Dimensional Modelling

• Outputs determine the Concrete and Reinforcement requirements

Design

Philosophy & Parameters

• Designed as a Buried pipe to Australian Standard AS/NZ3725

• Loading to AS/NZ5100 Road & rail

• Deflection and point load tests to AS/NZ 4058

• Concrete design in accordance with AS 3600

• Design life requirement - 100 years

Design Considerations

• Soil cover

• Deformation

• Extent of Corrosion

• Rail & Road loading

• Soil Modulus

• Support Zone Compaction probing

Concrete Mix Design

• Need to ensure Quality in consistent concrete is fundamental

• Designs to AS3600

• Test and trial mixings

• Computer controlled batching for mix traceability

• Mix blending is critical

• QA testing and site checks fundamental

Concrete & Rebar design

Reinforcement Specifications

• Single or Twin Cage Reo

• Elliptical cages Deformed bar- N12 to

N20

• Distribution bar N12 to N16

• Steel Dramix fibre

Concrete Specifications

• 40, 50 & 60 Mpa special design mix -

10mm aggregate with super plasticizer

• Fly Ash or GGBS replacement

Temporary Works

• Super strong light weight modular panel system

• Each Panel weighing less than 60 Kg

• Smooth external surface

• Design checked using FE modelling

• Design sign off to Australian Standards

Profiles

Using Tunneline for Rehabilitation on Bridges

Full profile Rehab

Top Arch

Abutments

Parabolic Arches

Jack Arches

Box Bridges

Applications

Arch Bridges

Flat deck bridges

Circular Culverts

Elliptical Bridge Culverts

Box Bridge Culverts

Pedestrian Underpass

Installation

Installation

• Initially set the invert

• Followed by sides

• Finally crown panel

• Stop End

• Concrete

• Strike and move forward

Site Quality Control Reinforcement

• Accuracy in placement

• Stability of the cage during erection

• Quality Procedures to ensure

standards are met

• Final sign off pre formwork erection

Quality Control Site Procedures

• Developed ITP with hold & verification points

• Concrete Testing pre start

• Design verification by third party

• Pre shutter build check sheet

• Pre pour check sheet

• Concrete Slump and Cylinder tests

• Final visual inspection

Pre Pour Inspection

Quality Management ITS-FM-QA-069 [1]

DETAILS OF POUR (to be completed and approved prior to pour)

CONTRACT/SITE NAME: DATE: ITS ENGINEER:

CONTRACT No: DAY: ITS SUPERVISOR:

CONTRACTOR: WEATHER: DRAWING NO:

SUPPLIER: AMBIENT TEMP: INSTALLATION METHOD:

TESTING REQUIREMENTS:

SHUTTER SIZE: SHAPE: CLEANLINESS REINFORCEMENT WITHIN

TOLERANCES PERMIT TO LOAD

CHAIN YES NO YES NO YES NO YES NO

Tolerances Height :- Plus or Minus 15mm

Width :- Plus or Minus 15mm

Level :- Plus or Minus 5mm

SIGNED FOR ITS DATE & TIME SIGNED FOR VicRoads DATE & TIME

DISTRIBUTION SITE Q.A FILE

CLIENT

OTHERS

Shutter Erection Tolerance Checklist

Quality Management ITS-FM-QA-077 [1]

CONTRACT NAME: DATE: ENGINEER:

CONTRACT No: DAY: SUPERVISOR:

CONTRACTOR: SHUTTER SIZE: SHAPE: DATE CHAIN WIDTH HEIGHT LEVEL DATE CHAIN WIDTH HEIGHT LEVEL

2 52

4 54

6 56

8 58

10 60

12 62

14 64

16 66

18 68

20 70

22 72

Tolerances Height :- Plus or Minus 15mm 24 74

Width :- Plus or Minus 15mm 26 76

Level :- Plus or Minus 5mm 28 78

30 80

32 82

34 84

36 86

38 88

40 90

DISTRIBUTION SITE Q.A FILE 42 92

CLIENT 44 94

OTHERS 46 96

48 98

50 100

Benefits

• 100 Year Design Life

• No disruption to the operational infrastructure above

• Flood Immunity is not compromised

• No Road or Track Closures

• Uses time tested materials

• Designed to Australian Standards

• Low carbon footprint

• Quick Program times

Thank You for Your Attention