7.4 Observations during construction

7.4.1 The observations during construction shall conform to EN 1997-1 (clause 2.7)

7.4.2 Where required information arising out of observations during construction or from monitoring shall be promptly reported.

7.4.3 Where a reinforced fill structure is to be placed on a slope or a ground with underlying rock, the exact delineation of the rock head shall be reported to enable final design of excavation, facing (where relevant), reinforcement lengths and spacing, to be completed.

7.4.4 Where a reinforced fill structure is to be placed on top of an anchored or soil nailed structure, the exact delineation of the anchors or soil nails shall be reported to enable final design of excavation, facing (where relevant), reinforcement lengths and spacing, to be completed.

7.4.5 Where significant consolidation and settlement of the foundation soil is expected, the reinforced fill structure may have to be built in more than one phase. The movements (and, where applicable, the pore pressure) shall be monitored as the construction progresses and reported as specified, for comparison with the predictions. The computation of the anticipated final settlements, as well as the design of the upper courses of the structure, shall be completed as soon as sufficient data is available.

7.4.6 Where settlements are expected the construction of any superimposed structures, including copings, may be delayed until future anticipated settlements fall within the settlement tolerances of superimposed structures. Where the superimposed structures will produce significant additional load the reinforced soil structure may be surcharged to the future load level.

7.5 Design output

The design output shall contain the required geometry of the structure to be built, relevant specification of materials or products assumed in the design together with any further details such as phasing of the works. Table 2 lists possible aspects of the design output.

Table 2 — Some possible aspects of design output
General Geometry including:
  • plan view;
  • typical cross sections;
  • elevation with layout.
Construction phases
Level of control
Construction tolerances
Climatic condition
Retained fill Physical properties:
  • unit weight;
  • particle size distribution (Dmax, Uniformity Coefficient)
  • friction angle and cohesion at design stress levels;
  • water content;
  • water and frost susceptibility, where appropriate.
Selected fill Physical properties:
  • maximum and minimum unit weight, Proctor density;
  • particle size distribution and / or friction angle and cohesion at design stress levels.
Electrochemical, chemical and biological properties:
  • minimum soil resistivity;
  • minimum/maximum pH;
  • maximum chloride and sulphate contents;
  • maximum organic and sulphide contents.
Frost susceptibility, where appropriate;
Placement requirements;
  • maximum dry density;
  • moisture content;
  • layer thickness;
  • installation method.
Reinforcement All types of reinforcement:
  • type and configuration, laying direction, seams and connections;
  • short term design strength;
  • long term design strength;
  • fill/reinforcement interaction;
  • mechanical damage related to fill particle size and angularity;
  • structural layout;
  • installation of test samples.
Steel reinforcement
  • grade;
  • type of coating.
Geosynthetic reinforcement
  • creep behaviour in accordance with EN ISO 13431.
Facing and connections Type and shapes
Aesthetic requirements
Performance level of facing
Performance level of reinforcement/facing connection
Maximum wind speed for erection of large panels
Top soil for greened faces Physical properties:
  • particle size distribution;
  • contents of organic material.
Chemical properties:
  • minimum/maximum pH.
Hydraulic properties;
  • capacity of water retention.

EN 14475:2006 Execution of special geotechnical works – Reinforced fill