APPENDIX TABLE 2:  FUEL CONSUMPTION ON UNPAVED ROADS

|=================================================================================================================|
|                                  | Main Road 59     | Main Road 51      | Main Road 46      | Main Road 47      |
|----------------------------------|------------------|-------------------|-------------------|-------------------|
|Measured IRI Values (m/km)        | 2,2 (2,1 wet)    | 5,1 (5,0 wet)     | 7,0 (4,9 wet)     | 11,1              |
|----------------------------------|------------------|-------------------|-------------------|-------------------|
|Average Longitudinal Slope (%)    | 1 - 3            | 1 - 3             | 1 - 3             | 1 - 3             |
|----------------------------------|------------------|-------------------|-------------------|-------------------|
|Standard Composition of Pavement  | Calcrete (fine)  | Calcrete gravel   | Coarsely graded   |Coarsely graded    |
|and general                       | (100-150 mm) on  | (100-150 mm) on   | quartz gravel     |quartz gravel      |
|Materials Specification           |fill (> 500 mm) of|fill (> 300 mm) of |(100-150 mm) on    |(100-150 mm) on    |
|                                  |natural sandy soil|natural sandy soil |fill (> 300 mm) of |fill (> 300 mm) of |
|                                  |                  |                   |natural sandy soil |quartz gravel/sandy|
|                                  |                  |                   |                   |soil               |
|----------------------------------|------------------|-------------------|-------------------|-------------------|
|Surface Description               |Smooth texture.   |Fair to slightly   |Rough surface with |Very rough (big    |
|                                  |No loose material |rough. Minimal     |excessive loose    |stones) with wind- |
|                                  |on surface.       |loose material.    |material.          |rows of loose      |
|                                  |Slightly damp     |Slightly damp      |Slightly damp      |gravel             |
|----------------------------------|------------------|-------------------|-------------------|-------------------|
|Rut Depth                         | < 10 mm          | < 20 mm           | 20 - 40 mm in     | > 40 mm due to    |
|                                  |                  |                   | loose material    | loose gravel wind-|
|                                  |                  |                   |                   | rows              |
|----------------------------------|------------------|-------------------|-------------------|-------------------|
|Corrugation                       |Practically none  |Very few. Roughness|Fair amount.       |Not much: more like|
|                                  |                  |due to larger      |Amplitude: ± 20 mm |depressions between|
|                                  |                  |stones             |Wave length: 500 mm|stones             |
|                                  |                  |                   |to 1.000 mm        |                   |
|----------------------------------|------------------|-------------------|-------------------|-------------------|
|Pot-holes                         |None              |Small depressions  |Practically none   |Depressions between|
|                                  |                  |between bigger     |                   |stones. Roughness  |
|                                  |                  |stones             |                   |due to oversize    |
|                                  |                  |                   |                   |stones             |
|----------------------------------|------------------|-------------------|-------------------|-------------------|
|Dust                              |Practically none  |Minimal            |Minimal            |Minimal            |
|----------------------------------|------------------|-------------------|-------------------|-------------------|
|Other Performance Parameter       |Good riding       |Fair riding quality|Fair to poor       |Very poor riding   |
|                                  |quality           |                   |riding quality     |quality            |
|----------------------------------|------------------|-------------------|-------------------|-------------------|
|Maximum Speed without Safety Risk |At least 100 km/h |At least 90 km/h   |Not more than      |Not more than      |
|                                  |                  |                   |90 km/h            |80 km/h            |
|----------------------------------|------------------|-------------------|-------------------|-------------------|
|Traffic (AADT)(average)(% Heavy)  | 60 (10%)         | 25 (10%)          | 60 (10%)          | 80 (10%)          |
|----------------------------------|------------------|-------------------|-------------------|-------------------|
| Age: Built:                      | > 20 years ago   | > 20 years ago    | > 20 years ago    | > 20 years ago    |
| Regravelled:                     | 5 - 10 years ago | 5 - 10 years ago  | middle 1990       | 5 - 10 years ago  |
|=================================================================================================================|
SOURCE: Petrol consumption measured: October 1990 to January 1991: with Toyota Highlux 4x4
Volumetrical measurements by 'HESSAG Kraftstoffverbrauchtester 1000B/400B'
Every fuel measuring point got 12 readings (2x2x3); altogether 8x12=96 points (8 sections)
NOTA: IRI values re-calculated from LDI-measurements as calibrated: QI = 31,96*LDI + 3,04
LDI - vehicle calibrated on 16 calibrating test sections near Windhoek: October 1990
for test sections between QI=21,2 (LDI=0,52 m/km)(IRI=2,1) (Premix: Concordia)
and QI=184 (LDI=5,44 m/km)(IRI=13,5)(S35/MR 52)
(rod and level)

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