1996 overview htrs

8/3/2019 1996 Overview Htrs

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THE HDM-4 TECHNICAL

RELATIONSHIPS STUDY

Asian Development Bank RETA 5549

Dr. Christopher R. Bennett

Team Leader

HDM-4 Technical Relationships Study

ISOHDM Secretariat

University of Birmingham

U.K.


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HIGHWAY DESIGN AND MAINTENANCE

STANDARDS MODEL (HDM-III)

Developed by the World Bank and released in 1987

Used in over 100 countries for different types of

investment studies

Predicts pavement performance over time and undertraffic and effects of maintenance on pavements

Predicts the effects of pavement and operating

conditions on vehicle operating costs (VOC)

Fundamental relationships based on researchconducted in Kenya, the Caribbean, India and Brazil

1971-1984


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DEVELOPMENT OF HDM MODEL

de Weille

1966

Highway Cost

Model

1971

Kenya Study

1971-75

HDM-II

1981

Caribbean Study 1977-82

India Study 1976-82

Brazil Study 1975-84

HDM-III

1987

HDM-VOC Model 4

1994


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LIMITATIONS OF HDM-III

Software difficult to use

Vehicle and tyre technology in the VOC studies

different to those of modern vehicles

HDM-III does not consider: Traffic congestion

Environmental impacts

Rigid pavements

Many types of flexible pavements Pavement texture and skid resistance

Freeze-thaw conditions

Traffic safety


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ISOHDM RESEARCH TEAMS

Malaysian TechnicalRelationships Study

Japanese Study Team

Technical Experts Swedish Study Team

University of

Birmingham SoftwareDevelopment

Finnish Study TeamChile Study Team


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STATUS - JANUARY 1996

ISOHDM Study Accomplishments Held Inception Workshop in Birmingham UK October 1993

Held Cold Climate Workshop in Sweden March 1994

Held International Workshop on HDM-4 in Malaysia

November 1994

Technical Relationships Study completed November 1995

Held Workshop on Road User Effects at TRL December

1995

Preliminary Specifications of HDM-4 RUE and RDMEModels completed

Programing of software has commenced and some

preliminary modules completed

Have established FTP site for accessing material on the

Internet


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HDM TECHNICAL RELATIONSHIPS

STUDY (HTRS)

Funded by ADB

Led by N.D. Lea International Ltd. (Canada)

Hosted and supported by Institut Kerja Raya

Malaysia (IKRAM)

Other participants:

Works Consultancy Services (New Zealand)

Department of Transport (South Africa)

Van Wyk and Louw (South Africa)

TRL (U.K.)

University of Auckland, University of Pretoria, Michigan

Technical Institute

Snowy Mountain Engineering Corporation (Australia)

Various Individuals


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HTRS RESEARCH APPROACH

Focused on areas deficient in HDM-III

Limited primary research - mainly desk study

Evaluated available research results and selecting

those most appropriate

Can be summarised as what were the areas where

HDM-III needs the most improvement and how could

this best be achieved with the available resources


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REVIEW OF PREVIOUS EXPERIENCES

WITH HDM

Contacted academics, consultants, governments, lending

agencies

To date have identified studies in over 100 countries

Used the results to identify the key areas requiring

attention in HDM-4 and for preparing draft specifications

Very few studies undertook rigorous calibration/

adaptation of HDM

Summarised parameter values by region and study

Identified alternative models and relationships to those in

HDM-III

VOC and RDME results presented in two internal reports


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KEY ISSUES - RDME

Standardising/Simplifying Data Collection

Generally, one set of models with different parameter

values by surface/base materials

Flexible pavements characterised by modifiedstructural number

Uses incremental models developed based on

structured empirical approach

Models provided in HDM-4 for Flexible

Rigid

Block

Unsealed


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KEY ISSUES - RDME

Extension of Flexible Pavement Deterioration Model

New distresses

Disaggregated distresses to account for individual

components

Extended models to account for more diverse

construction and climatic effects

Made models easier to calibrate

Rigid pavements

Work conducted by Chile team

Based on USA Ripper Model


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KEY ISSUES - RDME

Block pavements

Unsealed pavements

Includes models for surface texture and skid

resistance

Pavement Maintenance Effects

Covers full range of maintenance practices

More flexible than HDM-III


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HDM-4 PAVEMENT DISTRESSES

Cracking

Structural

Thermal

Reflection

Disintegration

Ravelling

Delamination Potholing

Longitudinal Profile

Roughness in IRI

m/km

Rutting

Densification

Structural

Plastic Deformation

Wear

Friction

Macrotexture Skid Resistance


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INTERACTION OF HDM-4 PAVEMENT

DISTRESSES

PavementStructure

PavementCondition

& Age

Traffic

CrackInitiation

RavellingInitiation

CrackProgression

RavellingProgression

PotholeDelaminationProgression

Roughness

Rutting

Deformation

ShoulderDeterioration

EdgeBreak

Shoulder Use on Narrow Roads

PotholeDelamination

Initiation


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HDM-4 ROAD USER EFFECTS

Road User

Effects

Vehicle Operating

Costs

Fuel

Consumption

Depreciation

Motorised Travel

Time CostsAccident Costs

Labour Hours

Oil and

Lubricants

Consumption

Interest

PartsConsumption

Tyre

Consumption

Overheads

Uncongested

Travel Time

Delay Due To

Congestion

Delay Due ToRoad Works

Environmental

Impact

NoiseVehicle

Emissions

Other EffectsNon-Motorised

Traffic

Impact on

Motorised

Traff ic

Operating

Costs

Travel Time

Road User Effects Researched by HTRS


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RUE STUDIES

NZVOC

COBA

VETO

RTIM

Scandanavian

Studies

HDM Study

KenyaCaribbean

Studies

Intermediate

Brazil Study

HDM

TRDF Model

MicroBENCOST

VOC

CB-ROADS

NIMPAC VOC

ARFCOMAustralian

Studies

South African

Studies

Winfrey

Claffey

Red Book

U.K. Studies


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REPRESENTATIVE VEHICLES

Motorised

MotorcyclesPassenger

CarsUtilities Buses

Motorcycles(1)

Small Car(2)

Medium Car(3)

Large Car(4)

Light DeliveryVehicle

(5)

Light GoodsVehicle

(6)

Four WheelDrive

(7)

Light Truck(8)

Medium Truck(9)

Heavy Truck(10)

ArticulatedTruck(11)

Mini-bus(12)

Light Bus(13)

Medium Bus(14)

Heavy Bus(15)

Coach(16)

Trucks

TYPES

CLASSES

CATEGORIES


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REPRESENTATIVE VEHICLES

Non-

motorised

Pedestrian BicycleCycle-

RickshawAnimal Cart Farm Tractor

Pedestrian BicyclePassenger

(Commercial)

Freight

(Commercial)

Freight(Private)

Animal Cart Farm Tractor

TYPES

CLASSES

CATEGORIES


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SPEED PREDICTION

Minor changes to HDM-

III Brazil free speed

model

Use 3-zone speed-flow model to consider

congestion effects

Qo Qnom Qult

Flow in PCSE/h

Speedkm/h

S1

S2

S3

Snom

Sult


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FUEL CONSUMPTION

Replaced HDM-III

Brazil model with one

based on ARRB

ARFCOM model Predicts fuel use as

function of power usage

TRACTIVE FORCES

Rolling, air, inertia, grade

and cornering resistance

ACCESSORIES

Cooling fan,power steering,

air conditioner,alternator, etc.

INTERNAL

ENGINE

FRICTION

DRIVE - TRAIN

INEFFICIENCIES

TOTAL POWER

ENGINE FUEL EFFICIENCY FACTOR

ESTIMATED FUEL CONSUMPTION


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FUEL CONSUMPTION - CONGESTION

AND ROAD EFFECTS

Modelling based on

acceleration noise -

standard deviation of

acceleration Comprised of natural and

traffic noise

Natural noise function of

slow-moving transport, side

friction, roughness

Use Monte Carlo simulation

to establish correction factors

through calibration routine

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Relative Traffic Flow (Q/Qult)

TotalAccelerationNoiseinm/s/s

.

Qo/Qult=0.0

Qo/Qult=0.1

Qo/Qult=0.2

Qo/Qult=0.3

Qo/Qult=0.4

Qo/Qult=0.5

natural noise

0

5

10

15

20

25

30

35

40

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Relative Flow

AdditioanlFuelinm

L/km

NZ - Two-lane

India - Two-lane

India - One-lane


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MAINTENANCE AND REPAIRS

Replaced HDM-III model with linear model

Linear model easier to calibrate and parameter

values provided for Brazil and India

Significant reduction in roughness effects forpassenger cars and light vehicles

Increased roughness effects for heavy buses

No benefit on parts from reducing roughness below 3

IRI m/km


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CAPITAL COSTS

Using Chesher and

Harrison Optimal Life

(OL) method

Uses maintenance coststream to determine OL

Model calibrated by

supplying target OL and

adjusting age exponent

in parts model

Costsperyear

Vehicle Age in years

Discounted Area = New Vehicle Price

RUN(OL)

Running Costs

OL


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OTHER RUE COMPONENTS

Tyre Consumption

Extending HDM-III mechanistic model to cover full

range of tyre types

Oil Consumption Adopting South African model

Overheads and Utilisation

Changes to methods from HDM-III

Traffic Safety

Using matrix approach

Effects of road works on users

Noise and Vehicle Emissions


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SUPPORTING STUDIES

Swedish Study

Tyre consumption

Emissions

Speed-flow

Cold-climate pavement deterioration

Japanese Team

Slow-moving transport

1996 overview htrs

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