1. FRENCH CODE
1) NF P DTU 13.2 (1978 & additional modifications 1991)
II ) Fascicule 62 titre V
III) Euro Code 7 : Geotechnical Design

2. DTU 13.2 Micropiles : - Drilled - Diameter < 250 mm
Classification based on the method of grouting

3. Design : - Structural bearing capacity - Geotechnical bearing capacity
- Control tests

4. Structural bearing capacity :
Micropiles (II, III, IV)
- Steel is only considered in the design
- Admissible stress
- Service loads (ELS) : sa = 0.5 se
- Ultimate loads (ELU) : sa = 0.75 se
- Reduction of the section for corrosion
- Buckling verfication (Mandel Method)

5. Geotechnical bearing capacity
Friction forces only
Qs = 2pDs L qs
Design Diameter (Ds)  :
Ds = a Dd (Dd = Drilled diameter)
Values of a

6. Determination of friction qs
Cohesive soils (laboratory tests)
Without results from in-situ tests
Cone penetration tests
Pressuremeter test of Menard

7. b = 1 (low injection pressure) (Type I, II)
Cohesive soils
qs = b Cu
b = 1 (low injection pressure) (Type I,  II)
b = 1.5 (high injection pressure) (III et IV)
Without results from in-situ tests

8. Cone penetration test
qs = qc /a

9. Pressuremeter test of Menard
Classification (soil, type of micropile)

11. Reduction factor for qs
Service loads (ELS) : 0.5
Ultimate loads (ELU) : 0.75

12. Control tests - Compression : 1 test / 200 micropiles
- Tension : 1 / 50
- N < 25, without test, reduction of the bearing capacity by 1.5