DETOUR10 Deterioration of Unpaved Roads (Ver 1.00)

7/31/2019 DETOUR10 Deterioration of Unpaved Roads (Ver 1.00)

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Deterioration of Engineered Unpaved Roadsusing HDM Relationships, Version 1.0, 9/9/99

DETOUR10

Rural Roads & Transport Thematic Group

The World Bank

Written by Rodrigo Archondo-Callao, The World Bank

Disclaimer

The Deterioration of Engineered Unpaved Roads Model software and documentation is copyrightedby the World Bank.

The World Bank makes no warranty in terms of correctness, accuracy, currentness, reliability or

otherwise regarding the literature and software. The user relies on the products of the software andthe results solely at his or her own risk. In no event will the World Bank or anyone else who has beeninvolved in the creation of this product be liable for its application or misapplication in the field. TheWorld Bank reserves the right to make revisions and changes from time to time without obligationto notify any person of such revisions and changes.

Warning

The model is designed primarily for engineered unpaved roads, of either gravel or earth surfacing,because the empirical models are based on a variety of such roads. When necessary it is possibleto use the relationships also for tracks as a first estimate, but the user needs to be aware that theenvironmental effects of drainage and rainfall may be poorly represented.The term "earth road" is sometimes used to denote a track as opposed to an engineered road. In thismodel, "earth road" denotes those engineered unpaved roads having a surface of predominantly fine


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deterioration relationships for unpaved roads of the Highway Design and Maintenance StandardsModel (HDM-III), which are the same as the forthcoming Highway Development and Management

Model (HDM-4).

To use the model, go to the "Road Deterioration" worksheet of this Excel workbook and enter thefollowing information in the input cells with yellow background located on the In Area.

- Road environment, geometry, and traffic characteristics- Gravel layer characteristics- Earth layer characteristics- Recurrent maintenance policy

- Periodic maintenance policy- Material loss calibration

DETOUR automatically computes the road deterioration over twenty years (traffic progression,

roughness progression, gravel thickness, and placement of new gravel layer timing) and presents theresults at the Out area, which is located below the input data area. The table just below the input

data area contains the main road deterioration results and a graph of roughness and gravel thicknessprogression, and the table to the right contains secondary road deterioration results.

Below the results area, you will find four buttons, which perform the following tasks.

Automatic Calculation On Turns the automatic calculation on

Automatic Calculation Off Turns the automatic calculation off

Manual Calculation Recalculates the workbook if automatic calculation is off

Print Report Prints all the inputs and main road deterioration results in one page

The Inputs

Enter the input data on the cells with yellow background. Don't change other cells or change the


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e) If you enter zero for the "Regravelling at Thickness" threshold, no regravelling will be doneand the model ignores the other periodic maintenance inputs.

Road Agency and User Costs

To estimate annual road agency maintenance costs and annual road user costs, got to the "RoadAgency and User Costs" worksheet of this Excel workbook and enter the following informationin the input cells with yellow background.

- Recurrent maintenance unit costs

- Periodic maintenance unit costs- Coefficients of cubic polynomials relating roughness to road user costs

DETOUR computes the resulting annual road agency, user costs and total society costs, and

displays the results below the input area every time the "Road Deterioration" worksheet is recalculated.Therefore, if you change any of the inputs on the "Road Agency and User Costs" worksheetthe results will not be updated automatically until the "Road Deterioration" worksheet is recalculated.To manually update the results of the "Road Agency and User Costs" worksheet, press: ctrl-m or thebutton named "Calculate Results" located at the bottom of the table. To print the table, press the

Excel print button.

Maintenance Levels

To perform a sensitivity analysis of a series of maintenance levels, go to the "Maintenance Levels"worksheet of this Excel workbook and enter the following information in the input cells with

yellow background.

- Grading interval- Spot regravelling- Regravelling threshold and thickness

To perform the sensitivity analysis, press the button "Press Here to Compute Results" located at the


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Support Tables

The "Support Tables" worksheet contains some suggested values, collected from many sources,for material properties, environments, and geometry of roads. Use these values as a guide toyour inputs.

Glossary

GVW Gross Vehicle WeightIRI International Roughness Index

km Kilometerm Metermm MilimeterRUC Road User Costs

veh Vehiclesvpd Vehicles per Day


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DETOUR - Deterioration of Engineered Unpaved Roads - Version 1.0

In Road Name Holeta-Muger

Environment, Geometry, and Traffic Rainfall (m/month) 0.08Road Width (m) 6.0 Shoulder Width (m) 0.0Rise and Fall (m/km) 19 Horizontal Curvature (degree/km) 68Light Vehicle Traffic, GVW3.5 tons (vpd) 50 Heavy Vehicle Traffic Growth (%) 6%

Gravel Layer Characteristics Maximum Roughness (IRI) 15Thickness (mm) 50 Maximum Particle Size (mm) 30.0Age (years) 10 Plasticity Index (#) 7.0Mechanical Compaction (Y/N) Y % Passing 2.000 mm Sieve 65.0

Current Roughness (IRI) 22 % Passing 0.425 mm Sieve 40.0

Minimum Roughness (IRI) 2 % Passing 0.075 mm Sieve 10.0Earth Layer Characteristics Plasticity Index (#) 7.0Minimum Roughness (IRI) 0 % Passing 2.000 mm Sieve 70.0

Maximum Roughness (IRI) 0 % Passing 0.425 mm Sieve 50.0Maximum Particle Size (mm) 4.8 % Passing 0.075 mm Sieve 20.0

Recurrent Maintenance PolicyGrading Interval (days) 180 Spot Regravelling (m3/km/year) 5

Periodic Maintenance Policy Maximum Roughness (IRI) 0New gravel layer at gravel thickness (mm) 50 Maximum Particle Size (mm) 21.9New gravel layer thickness (mm) 200 Plasticity Index (#) 10.1Mechanical Compaction (Y/N) Y % Passing 2.000 mm Sieve 51.1

Initial Roughness (IRI) 2 % Passing 0.425 mm Sieve 41.6Minimum Roughness (IRI) 2 % Passing 0.075 mm Sieve 25.5

Material Loss CalibrationGravel Loss Factor 1.0 Traffic-induced Loss Factor 1.0

Out Road DeteriorationGravel Gravel

Traffic Roughness Thickness Layer

Year (vpd) (IRI) (mm) (in year)1 60 12.6 234 1

2 64 3.0 218

3 67 5.0 201

4 71 7.1 1845 76 8.5 167 2.0

4.0

6.0

8.0

10.012.0

14.0

16.0

Roughness,IR

I


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InRoad Name Holeta-MugerEnvironment, Geometry, and TrafficRoad Width (m) 6.0 Shoulder Width (m) 0.0

Rise and Fall (m/km) 19 Horizontal Curvature (degree/km) 68

Gravel Thickness (mm) 50 Rainfall (m/month) 0.08Light Vehicle Traffic, GVW3.5 tons (vpd) 50 Heavy Vehicle Traffic Growth (%) 6%

Gravel Layer Characteristics Earth Layer CharacteristicsPlasticity Index (#) 7.0 Plasticity Index (#) 7.0

Maximum Particle Size (mm) 30.0 Maximum Particle Size (mm) 4.8

% Passing 2.000 mm Sieve 65.0 % Passing 2.000 mm Sieve 70.0% Passing 0.425 mm Sieve 40.0 % Passing 0.425 mm Sieve 50.0% Passing 0.075 mm Sieve 10.0 % Passing 0.075 mm Sieve 20.0

Recurrent Maintenance Policy Recurrent Maintenance Unit Costs

Grading Interval (days) 180 Grading ($/km) 400Spot Regravelling (m3/km/year) 5 Spot Regravelling ($/m3) 12.00

Routine Maintenance ($/km-year) 1000.00

Periodic Maintenance Policy Periodic Maintenance Unit CotsNew gravel layer at gravel thickness (mm) 200 Gravel Layer ($/m3) 10.00

New gravel layer thickness (mm) 50

Light Vehicles Road User Costs Coefficients Heavy Vehicles Road User Costs CoefficientsRUC = 0.381600 RUC = 1.117900($/veh-km) + -0.000428 * IRI ($/veh-km) + 0.017005 * IRI

+ 0.000928 * IRI 2 + 0.000808 * IRI 2

+ -0.000018 * IRI 3 + -0.000014 * IRI 3

Out Road Agency Costs RoadSpot Routine Gravel Total Total Total User Society

Gradings Regravelling Maintenance Layer Recurrent Periodic Agency Costs Costs

Year ($/km) ($/km) ($/km) ($/km) ($/km) ($/km) ($/km) ($/km) ($/km)1 811 60 1,000 12,000 1,871 12,000 13,871 27,905 41,776

2 811 60 1,000 0 1,871 0 1,871 24,240 26,111

3 811 60 1,000 0 1,871 0 1,871 26,664 28,535

4 811 60 1,000 0 1,871 0 1,871 29,516 31,387

5 811 60 1,000 0 1,871 0 1,871 32,214 34,085

6 811 60 1 000 0 1 871 0 1 871 34 598 36 470


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In Out

Maintenance Level Average Values Over 20 YearsGrading Spot New Gravel New Gravel Gravel Agency Road User Society

Sensitivity Interval Regravelling Threshold Thickness Roughness Thickness Costs Costs CostsCases (days) (m3/km/year) (mm) (mm) (IRI) (mm) (000$/km) (000$/km) (000$/km)

1 365 5 50 200 12.7 142 2660 22585 25245

2 350 5 50 200 12.6 142 2677 22434 25111

3 335 5 50 200 12.5 142 2696 22276 249724 320 5 50 200 12.4 142 2716 22108 24824

5 305 5 50 200 12.3 142 2739 21930 246696 290 5 50 200 12.1 142 2763 21742 245057 275 5 50 200 12.0 142 2791 21543 24334

8 260 5 50 200 11.8 142 2822 21333 24154

9 245 5 50 200 11.6 142 2856 21107 23962

10 230 5 50 200 11.4 142 2895 20863 2375811 215 5 50 200 11.2 142 2939 20601 23540

12 200 5 50 200 11.0 142 2990 20316 23306

13 185 5 50 200 10.8 142 3049 20006 23055

14 170 5 50 200 10.5 142 3119 19663 22782

15 155 5 50 200 10.2 142 3202 19287 2248916 140 5 50 200 9.8 142 3303 18852 22155

17 125 5 50 200 9.4 142 3428 18367 2179518 110 5 50 200 9.0 142 3587 17835 21423

19 95 5 50 200 8.4 142 3797 17250 2104720 80 5 50 200 7.9 142 4085 16605 20690

20690

Out

10.0

12.0

14.0

20,000

25,000

30,000

IRI)

year)


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0

20

40

60

80

100

0.00 0.01 0.10 1.00 10.00 100.00 1000.00

%l

essthand

Particle Diameter, d (mm)

Grading Curves

Gravel Layer Earth Layer

CLAY SILT SAND GRAVEL STONEFINE COARSE FINE MEDIUM COARSE


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Support Tables for Reference

Materials Database

Maximum Percent Percent PercentParticle Passing Passing Passing

Size Plasticity 2.0 mm 0.425 mm 0.075 mmSource Description Layer (mm) Index Sieve Sieve SieveHDM-4 Volcanic gravels angular Surface 25.0 17.0 49.3 38.0 23.5HDM-4 Quartzitic gravels Surface 23.8 9.1 57.5 44.6 24.2HDM-4 Lateritic gravels Surface 21.9 10.1 51.1 41.6 25.5HDM-4 Coral gravels angular Surface 21.0 13.0 64.3 49.0 25.0HDM-4 Earth Surface 4.8 15.8 90.5 84.9 70.2HDM-4 Gravel-sand mixture with excess of fines Subgrade 17.0 17.0 46.0 34.0 23.0

HDM-4 Well-graded gravel-sands with small clay content Subgrade 13.0 15.0 60.0 40.0 18.0HDM-4 Sand with excess fines Subgrade 12.0 8.3 88.0 68.5 27.0HDM-4 Clayey silts (inorganic) Subgrade 10.0 17.5 88.0 77.0 54.0HDM-4 Clays (inorganic) of medium plasticity Subgrade 8.0 18.8 83.5 77.0 59.0HDM-4 Clays (inorganic) of high plasticity Subgrade 4.0 34.3 86.3 81.5 74.0HDM-III Quartzitic gravels Surface 23.8 9.1 57.5 44.6 24.2HDM-III Lateritic gravels Surface 21.9 10.1 51.1 41.6 25.5HDM-III Earth Subgrade 4.8 15.8 90.5 84.9 70.2

Geometry Database

Riseand HorizontalFall Curvature

Source Description (m/km) degrees/km)HDM-4 Straight and level 1 3HDM-4 Mostly straight and gently undulating 10 15HDM-4 Bendy and generally level 3 50HDM-4 Bendy and gently undulating 15 75

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HDM-4 Bendy and severely undulating 25 150HDM-4 Winding and gently undulating 20 300HDM-4 Winding and severely undulating 40 500HDM Manager Flat terrain 0 0

HDM Manager Level terrain 10 50HDM Manager Rolling terrain 20 150

HDM Manager Hilly terrain 50 300HDM Manager Mountainous terrain 80 500

Environment Database

Monthly Annual

Rainfall RainfallSource Description (m/month) (mm/year)HDM-4 Arid 0.015 180HDM-4 Semi-Arid 0.050 600HDM-4 Semi-Humid 0.100 1200

HDM-4 Humid 0.175 2100HDM-4 Per-Humid 0.210 2520

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DETOUR10 Deterioration of Unpaved Roads (Ver 1.00)