Base Resistance
Determination of base resistance qb should be part of the geological survey.
Recommended values of resistance qb [kPa] can be found in professional literature for specific soils and structure types:
- for bored piles:
qb | ||||||
non-cohesive soil | cohesive soil | |||||
qc | cu | |||||
s/D | 7,5 | 15 | 25 | 100 | 150 | 250 |
0,02 | 550-800 | 1050-1400 | 1750-2300 | 350-450 | 600-750 | 950-1200 |
0,03 | 700-1050 | 1350-1800 | 2250-2950 | 450-550 | 700-900 | 1200-1450 |
sg=0,10 | 1600-2300 | 3000-4000 | 4000-5300 | 800-1000 | 1200-1500 | 1600-2000 |
- for driven piles:
qb | ||||||
non-cohesive soil | cohesive soil | |||||
qc | cu | |||||
s/Deq | 7,5 | 15 | 25 | 100 | 150 | 250 |
0,035 | 2200-5000 | 4000-6500 | 4500-7500 | 350-450 | 550-700 | 800-950 |
sg=0,10 | 4200-6000 | 7600-10200 | 8750-11500 | 600-750 | 850-1100 | 1150-1500 |
where: | qc | - | cone penetration resistance, CPT [MPa] |
cu | - | total cohesion of the soil [kPa] | |
s | - | pile settlement | |
sg | - | limit settlement | |
D, Deq | - | pile diameter |
Intermediate values may be linearly interpolated.
Literature:
EA-Pfähle, ISBN: 978-3-433-03005-9.