Use soils in engineering


This unit describes the performance outcomes, skills and knowledge required to understand the engineering properties of soils and to carry out appropriate soil tests.

The unit of competency is applied by technicians in a civil and structural engineering environment in analysing soils for construction projects.

No licensing, legislative, regulatory or certification requirements apply to this unit at the time of publication.

PREREQUISITE UNIT DCSBSE612 Use basic soils in engineering


Elements describe the essential outcomes.


Performance criteria describe the performance needed to demonstrate achievement of the element.

1.    Determine soil pressure on retaining walls.

1.1.      Describe Rankine’s theory for predicting active and passive soil pressure

1.2.      Describe Coulomb’s wedge theory for lateral soil pressure

1.3.      Calculate foundation pressure on footings by using the mid-third rule

2.    Determine shear strength of soils.

2.1.      Describe in detail a shear-box test for sands and for clay

2.2.      Outline the outcome of the shear-box test as well as any other phenomena observed during the test.

2.3.      Describe a tri-axial test

2.4.      Apply Mohr’s circle method for shear determinations

3.    Perform soil slope stability calculations.

3.1.      Develop and apply stability calculations for granular and cohesive soils

4.    Determine methods of soil stabilization. 4.1.      Compare the following methods of soil stabilisation in terms of applications, effectiveness and efficiency:

(a)  cement

(b)  mechanical

(c)  lime

(d)  bitumen

(e)  chemical

4.2.      Describe in detail a CBR test on a gravel soil

4.3.      Outline the outcome of a CBR test as well as any other phenomena observed during the test.

5.    Describe piled footings

5.1.      Summarise the theory of piles

5.2.      Outline significant features of the following types of pile:

(a)  steel

(b)  timber

(c)  concrete

(d)  Franki

(e)  driven

(f)  bored

6.     Evaluate the methods used for site investigations.

 6.1.      Describe in detail a field dry-density test.

6.2.       Outline the outcome of a field dry-density test as well as any other phenomena observed during the test.

6.3.       Outline procedures for the following types of penetrometer test:

(a)  Cone method

(b)  Sand method

6.4.       Explain seismic and sampling methods.


Foundation skills essential to performance are explicit in the performance criteria of this unit of competency.


41962 Use soils in engineering is equivalent.



Assessment requirements for DCSSOL623 Use soils in engineering


To achieve competency in this unit a person must satisfy the requirements of the elements and performance criteria, foundation skills and range of conditions included in the unit.

The person must also:

  • record the results of at least one test series that includes a shear-box, tri-axial, CBR, and dry density tests.

Note: If a specific volume or frequency is not stated, then evidence must be provided at least once for each criterion.


To achieve competency in this unit a person must demonstrate knowledge of:

  • collating and interpreting data from tests and write laboratory reports
  • principles of soils in the context of pressure, force and friction
  • relevant mathematics and trigonometry symbols, concepts and calculations


Assessment conditions:

All assessment must be completed in accordance with work health and safety standards.

When assessments are conducted remotely, invigilation software must be used to ensure authenticity of work completed.

Model answers or marking guides must be provided for all assessments to ensure reliability of assessment judgements when marking is undertaken by different assessors.

The candidate must have access to all tools, equipment, materials and documentation required.

Assessor Requirements:

Assessors must satisfy the assessor requirements in the standards for registered training organisation (RTOs) current at the time of assessment.

Assessors must also hold a tertiary qualification in engineering or related field.

Assessors must have worked for at least 3 years in industry where they have applied the skills and knowledge covered in this unit of competency.

The RTO must also ensure that trainers and assessors keep their industry knowledge up to date through ongoing professional development.

The RTO must take appropriate steps, as an ongoing procedure, to verify information about trainer and assessor’s qualifications, vocational competencies and current industry skills


Software/Hardware Used


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