|
Specification Notes
| TABLE 1 - CALIFORNIA BEARING RATIO |
| |
California Bearing Ratio (CBR)% |
| |
Plasticity Index |
Depth of water table below formation level |
| Type of soil |
% |
>600mm |
<600mm |
| Heavy Clay |
70 |
2 |
1 |
|
60 |
2 |
1.5 |
|
50 |
2.5 |
2 |
|
40 |
3 |
2 |
| Silty Clay |
30 |
5 |
3 |
| Sandy Clay |
20 |
6 |
4 |
|
10 |
7 |
5 |
| Silt |
n/a |
2 |
1 |
| Sand(poorly graded) |
non-plastic |
20 |
10 |
| Sand(well-graded) |
non-plastic |
40 |
15 |
| Well-graded sandy gravel |
non-plastic |
40 |
15 |
| |
| TABLE 2 - SUB BASE THICKNESSES FOR HIGHWAY PAVEMENTS |
| Type of Pavement |
| California Bearing Ratio (CBR) |
Pedestrian Area |
Footway |
Car Park |
Cul-de-sac |
Minor Residential Road |
Roads with up to 25 Public Service Vehicles per day |
Roads with 25-50 Public Service Vehicles per day |
Residential roads with over 50 Public Service Vehicles per day |
Main Roads |
| % |
mm |
mm |
mm |
mm |
mm |
mm |
mm |
mm |
mm |
| <2 |
|
520 |
530 |
550 |
550 |
610 |
640 |
670 |
700 |
| 2 |
|
370 |
380 |
400 |
400 |
460 |
490 |
520 |
550 |
| 3 |
|
280 |
280 |
300 |
300 |
350 |
370 |
390 |
430 |
| 4 |
|
210 |
220 |
230 |
230 |
280 |
300 |
310 |
330 |
| 5 |
|
170 |
180 |
190 |
190 |
230 |
240 |
260 |
280 |
| 6 |
|
130 |
130 |
140 |
140 |
180 |
190 |
200 |
220 |
| > 7 |
|
100 |
100 |
110 |
110 |
150 |
150 |
160 |
180 |
| The recommended thicknesses for pedestrian areas and footways include a safety factor to allow for occasional over-riding by vehicles
|
|
|
Ketley Brick Company Ltd Home
Dreadnought Works, Pensnett, Brierley Hill, West Midlands, DY5 4TH, UK.
Tel: 01384 78361. Fax: 01384 74553 Email: info@ketley-brick.co.uk
Ketley Brick Company Ltd. is a company registered in England and Wales
with Reg number 699040. |
