| Components | Ideal | Brick | Plain Cement Con- crete | Bitumi- nous Mac- adam | Water- bound Mac- adam | ||
|---|---|---|---|---|---|---|---|
| V | W | X | |||||
| First cost, cheapness | 15 | 15 | 15 | 8 | 10 | 10 | 15 |
| Maintenance, cheapness | 25 | 25 | 20 | 25 | 20 | 20 | 10 |
| Durability | 7 | 7 | 7 | 7 | 5 | 5 | 3 |
| Ease of maintenance | 8 | 10 | 10 | 7 | 8 | 8 | 10 |
| Cleanliness | 5 | 5 | 5 | 3 | 3 | 5 | 2 |
| Low tractive resistance | 10 | 5 | 5 | 5 | 4 | 4 | 4 |
| Non-slipperiness | 10 | 10 | 10 | 4 | 7 | 5 | 10 |
| Sanitariness | 5 | 5 | 5 | 4 | 4 | 5 | 3 |
| Noiselessness | 5 | 5 | 5 | 3 | 3 | 5 | 4 |
| Acceptability | 5 | 5 | 8 | 2 | 3 | 4 | 5 |
| Favorableness to travel | 5 | 8 | 10 | 3 | 5 | 6 | 8 |
| Total | 100 | 100 | 100 | 71 | 72 | 77 | 74 |
Anderson gives the following economical table to assist in arriving at a proper type of surfacing:[187]
Method of Making Economical Comparison of Road Surfaces
| Item | Possible Types of Surfacing | ||
|---|---|---|---|
| A | B | C | |
| Estimated life of surface with proper maintenance, years | 4 | 8 | 12 |
| Original construction cost per mile | $ 8,000 | $15,000 | $30,000 |
| Annual charges for interest, depreciation and resurfacing | 2,364 | 2,528 | 3,797 |
| Cost of maintaining surface per mile, average, annual | 1,000 | 750 | 200 |
| Total cost per mile at end of 12th year, period | 40,368 | 39,336 | 47,964 |
| Value of road surface per mile at end of 12th year period | .... | 7,500 | 12,000 |
| Net outlay per mile of road | 40,368 | 32,836 | 35,964 |
The choice of selection here is evidently between B and C, with the figures so close together that the one with the least number of uncertainties would probably be adopted if economy is the determining factor.
Another method of making economical comparisons is shown in the table and plot following:
| Item | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
|---|---|---|---|---|---|---|---|
| Earth Road | Gravel Road | Bitumi- nous Macadam and concrete | Portland Cement Concrete | Sheet Asphalt Bitulithic | Brick Stone Block | Wood Block | |
| First cost per mile | $1,000 | $5,000 | $10,000 | $20,000 | $30,000 | $40,000 | $50,000 |
| Annual Interest, 5 per cent | 50 | 250 | 500 | 1,000 | 1,500 | 2,000 | 2,500 |
| Annual Maintenance | 250 | 250 | 500 | 100 | 100 | 50 | 50 |
| Life of surface, yrs. | 0 | 5 | 10 | 20 | 20 | 25 | 25 |
| Cost of resurfacing | $ 0 | $2,500 | $ 5,000 | $15,000 | $15,000 | $25,000 | $35,000 |
| Annual Sinking Fund 31⁄2 per cent | 0 | 466 | 427 | 530 | 530 | 884 | 899 |
| Annual Total Cost | 300 | 966 | 1,427 | 1,630 | 2,130 | 2,934 | 3,449 |
| Daily Cost, per mile | 0.82 | 2.74 | 3.90 | 4.45 | 5.84 | 8.03 | 9.46 |
Plot showing cost of several types of roads under varying traffic density. When the traffic density of road No. 1 (Earth and sand clay) becomes greater than 300 or 400 vehicles per day the curve would turn up because the maintenance costs would be increased. Similarly for Nos. 2 and 3 for 1600 to 2000 vehicles per day.