BS EN 14199:2015

Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Information needed for the execution of the works
5 Geotechnical investigation
6 Materials and products
7 Considerations related to design
8 Execution
9 Supervision, monitoring and testing
10 Records
11 Special requirements
Annex A (informative) - Execution methods of micropiles
Annex B (informative) - Guidance on minimum cover
        (in mm) for bearing element of low strength steel
        for cast in situ micropiles
Annex C (informative) - Borehole testing and pregrouting
Annex D (informative) - Guideline for a record for micropiles
Annex E (informative) - Degree of obligation of the provisions
Bibliography

Presents general principles for the execution of micropiles.

1.1 This European Standard establishes general principles for the execution of micropiles. They are for drilled piles constructed using a drilling tool with a diameter less than 300mm. NOTE1 This European Standard is not applicable to driven piles, the execution of which is governed by EN12699 . NOTE2 For a definition of shaft diameter see 3.3. 1.2 Micropiles are structural members to transfer actions to the ground and can contain bearing elements to transfer directly or indirectly loads and or to limit deformations. For examples of micropiles see Figure1, Figure2 and Figure3. Their shaft and base resistance can be improved (mostly by grouting) and they can be constructed with (see Figure4): uniform cross section (straight shaft); or telescopically changing shaft dimensions; shaft enlargements; and/or base enlargement. 1.3 Other than practical considerations, there are no limitations regarding, length, inclination (definition of inclination, see Figure5), slenderness ratio or shaft and base enlargements. 1.4 The provisions of this European Standard apply to (see Figure6): single micropiles; micropile groups; reticulated micropiles; micropile walls. 1.5 The material of micropiles covered by this European Standard can be: steel or other reinforcement materials; grout, mortar or concrete; a combination of above. 1.6 Micropiles can be used for: working under restricted access and/or headroom conditions; foundations of new structures (particularly in very heterogeneous soil or rock formations); reinforcing or strengthening of existing structures to increase the capacity to transfer load to depth with acceptable load settlement characteristics, e.g. underpinning works; reducing settlements and/or displacements; forming a retaining wall; reinforcing of soil to form a bearing and/or retaining structure; improving slope stability; securing against uplift; other applications where micropile techniques are appropriate. 1.7 Deep mixing columns according to EN14679 are not included in this European Standard. Columns constructed by jet grouting are covered by EN12716 . Ground anchors are covered by EN1537 .