Secant piled wall using segmental casing


The purpose of this standard is to provide the candidate with details of why and how segmental casing is used in the construction of secant piled walls. This standard was previously called Using segmental casing, extractors and ocsillators for secant piled wall construction.

CITB has developed this standard in discussion with industry


Minimum 1 day of 6 learning hours


The purpose of this standard is to provide the candidate with details of why and how segmental casing is used in the construction of secant piled walls.



  • basement & substructure design principles
    • basement grade & water tightness
    • propping
  • secant wall design principles
    • basement depth and retained height
    • secant wall type (hard/hard, hard/firm, hard/soft)
    • reinforcement
    • concrete mix design
  • general methodology of installation
    • tolerances and how to achieve them in relation to: guide-wall construction, plan position, verticality, casing length.
    • sequencing
    • use of extractors
    • use of oscillators
    • casing type, maintenance & management
    • associated risks

Occupational relevance

Training delivered against this standard would be relevant to the following occupational groups:

  • supervision
  • management and supervision.

Candidate pre-requisites

A basic knowledge of piling techniques is required.


As a minimum, course instructors must be able to demonstrate that, in relation to this standard, they have:

  • A train the trainer or instructional techniques course certificate
  • Successfully completed training to this standard 
  • At least 2 years relevant industrial experience
  • A verifiable CV.


Delivery may be in an on or off the job environment.

All materials and equipment must be of a suitable quality and quantity for candidates to achieve learning outcomes, and must comply with relevant legislation.

The class size and candidate/instructor ratio must allow training to be delivered in a safe manner and enable candidates to achieve the learning outcomes.

The following delivery methods may be used in the delivery of this standard:

  • classroom
  • a blend of classroom and e-learning

This standard is considered to contain 51 per cent or more theoretical learning.


For the successful completion of training, candidates must complete an end of course practical assessment or knowledge test that measures the learning outcomes and has a pass or fail criteria.

Quality assurance

Quality assurance against this standard will require initial approval of the training organisation and their content mapped to the standard. 

CITB will also conduct an approval intervention, either desk-based or centre visit, to ensure the training organisation can meet the requirements of the Training Standard. 

Approved training organisations (ATOs) will be required to present information on records of training and assessment upon request to CITB for desk-based analysis. They will also be visited annually by the CITB quality assurance team.


There are no mandatory renewal or recommended refreshment requirements for this standard.

Approval date

November 2018

Review cycle

Either on request or in 3 years from approval date.

Learning outcomes

The candidate will be able to Additional guidance to support learning outcome

Describe how and why basements are constructed in the modern environment


Describe the basic principles of a retaining structure to form a basement


Describe types of secant piled wall and the differences between them


Describe how required tolerances are achieved and the impact that they can have on basement construction

ICE Specification for Piling & Embedded Retaining Walls

Outline the importance of construction sequencing for secant walls


Explain how and why casing extractors and oscillators are used


Outline of how and why casing management and maintenance is important


Identify the main safety risks associated with secant piled wall construction


Additional information about this standard

See the Institute for Civil Engineers publication: Specification for Piling and Embedded Retaining Walls, ICE, Third Edition