EN 15237:2007

Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Information needed for the execution of the work
5 Geotechnical investigations
    5.1 General
    5.2 Specific requirements
6 Materials and product
    6.1 General
    6.2 Raw materials of prefabricated drains
    6.3 Band drains
    6.4 Prefabricated cylindrical drain
    6.5 Sand drains
7 Considerations related to design
    7.1 Field trials
8 Execution
    8.1 Method statement
    8.2 Preparation of the site
    8.3 Drain installation
    8.4 Special aspects
9 Supervision and monitoring
    9.1 Supervision
    9.2 Monitoring
10 Records
    10.1 Records during construction
    10.2 Records at the completion of the work
11 Special requirements
    11.1 General
    11.2 Safety
    11.3 Environmental protection
    11.4 Impact on adjacent structures
Annex A (informative) Practical aspects of vertical drainage
Annex B (informative) Aspects of design
Annex C (informative) Degree of obligation of the specifications
Bibliography

This European Standard establishes general principles for the execution, testing, supervision and monitoring of vertical drain projects.This European Standard includes the application of prefabricated vertical drains and sand drains and deals with requirements to be placed on design, drain material and installation methods. This European Standard applies to the improvement of low-permeability, highly compressible soils by vertical drainage and preloading. Information regarding loading (embankment, vacuum or ground water lowering) and preloading is given in informative Annexes A and B.Vertical drainage is used both in on land and in marine constructions for the following purposes:(pre-)consolidation and reduction of post-construction settlements;speeding up the consolidation process by decreasing the path lengths for pore water dissipation;increase of stability (by increasing effective stresses in the soil);groundwater lowering;mitigation of liquefaction effects.In each case there is an overall treatment of the soil (the volume of the drains is small in relation to the soil volume treated).This European Standard does not include soil improvement by means of wells, gravel and stone columns, large-diameter geotextile enclosed columns or reinforcing elements.Vertical drainage can also be combined with other foundation or ground improvement methods, e.g. electro osmosis, piles and compacted sand piles, dynamic compaction and deep mixing.Guidance on practical aspects of vertical drainage, such as investigation of drain properties, execution procedures and equipment, is given in Annex A. Investigation of soil characteristics and assessment of design parameters, which are affected by drain properties and execution, are presented in Annex B.