|
|
Soil Type and Compaction Level
(standard Proctor density)
|
|
|
Class I
|
Class II
|
Class III
|
|
|
|
GW, GP, SW, SP
|
GM, SM, ML(1), and GC and
SC with < 20% passing the 200 sieve
|
|
Cover Height ft.(m)
|
compacted psi
(kPa)
|
uncompacted psi
(kPa)
|
95% psi
(kPa)
|
90% psi
(kPa)
|
85% psi
(kPa)
|
95% psi
(kPa)
|
90% psi
(kPa)
|
85% psi
(kPa)
|
|
1
(0.3)
|
2350
(16200)
|
470
(3240)
|
2000
(13790)
|
1280
(8830)
|
470
(3240)
|
1420
(9790)
|
670
(4620)
|
360
(2480)
|
|
5
(1.5)
|
3180
(21900)
|
510
(3500)
|
2450
(16900)
|
1440
(9900)
|
510
(3500)
|
1610
(11100)
|
720
(5000)
|
380
(2600)
|
|
10
(3.0)
|
3900
(26900)
|
550
(3800)
|
2840
(19600)
|
1580
(10900)
|
550
(3800)
|
1730
(11900)
|
750
(5200)
|
400
(2800)
|
|
15
(4.6)
|
4460
(30800)
|
590
(4100)
|
3090
(21300)
|
1660
(11400)
|
590
(4100)
|
1790
(12300)
|
760
(5200)
|
410
(2800)
|
|
20
(6.1)
|
4980
(34300)
|
620
(4300)
|
3270
(22500)
|
1730
(11900)
|
620
(4300)
|
1840
(12700)
|
770
(5300)
|
420
(2900)
|
|
25
(7.6)
|
5500
(37900)
|
650
(4500)
|
3450
(23800)
|
1800
(12400)
|
650
(4500)
|
1880
(13000)
|
790
(5400)
|
430
(3000)
|
|
30
(9.1)
|
5900
(40700)
|
690
(4800)
|
3610
(24900)
|
1860
(12800)
|
690
(4800)
|
1920
(13200)
|
810
(5600)
|
450
(3100)
|
|
35
(10.7)
|
6300
(43400)
|
720
(5000)
|
3770
(26000)
|
1920
(13200)
|
720
(5000)
|
1960
(13500)
|
830
(5700)
|
460
(3200)
|
|
40
(12.2)
|
6700
(46200)
|
780
(5400)
|
3930
(27100)
|
1980
(13700)
|
780
(5400)
|
2010
(13900)
|
860
(5900)
|
480
(3300)
|
|
45
(13.7)
|
7100
(49000)
|
790
(5400)
|
4090
(28200)
|
2040
(14100)
|
790
(5400)
|
2050
(14100)
|
880
(6100)
|
490
(3400)
|
|
50
(15.2)
|
7500
(51700)
|
830
(5700)
|
4250
(29300)
|
2100
(14500)
|
830
(5700)
|
2090
(14400)
|
900
(6200)
|
510
(3500)
|
|