List the assessment methods to be used and the context and resources required for assessment. Copy and paste the relevant sections from the evidence guide below and then re-write these in plain English.
An individual demonstrating competency must satisfy all of the elements and performance criteria in this unit.
There must be evidence that the individual has analysed the edaphic interactions of trees and structures for a specific site and has prepared a minimum of two reports, which must include:
a report on damage to structures by tree roots
a report on the stability of tree with a defective or damaged root plate.
There must also be evidence that the individual has:
investigated soil conditions that contribute to structure and tree stability, including:
angle of repose of soil materials
soil plasticity
impact of soil moisture on soil cohesion and plasticity
modes of soil liquefaction
investigated and tested soils for properties affecting soil conditions, including:
measured soil moisture content and field capacity
determined soil texture
assessed level of soil cohesion
determined shear strength of the soil
investigated load bearing capacity of soil
calculated mass of the soil plate
determined root morphology, division and distribution and amount of buttressing of tree
determined species characteristics for development of tap root system
determined anatomical features of tree roots and identified tree roots for a given tree
conducted research tests to determine forces and pressures exerted by trees through the soil
estimated and measured dimensions of roots exerting a force on a structure
calculated total surface area of the roots exerting a force on a structure
calculated force exerted by roots per unit of surface area of structure
calculated total force exerted by roots of a given surface area
measured and determined volume of structure
researched and calculated mass of structures
determined impact of gravity on mass
determined effect of leverage on the forces exerted by tree roots on structure
determined factors of root–soil matrix interactions
investigate area of contact between root and soil
investigated elasticity, tensile strength and breaking stress of roots
investigated root cross-sectional morphology
assessed root plate for damage, deficiencies or defects that may contribute to tree failure
estimated impact of static and dynamic testing for root plate stability
evaluated possible root failure by root breakage
evaluated possible anchorage failure by soil breakage or slippage
investigated and assessed:
effects of increasing mass
methods for, and effects of, increasing the modus of rupture
effects of use of curved structures
effects of soil mass and friction
effects of use of anchors, braces and props
compiled investigations and assessments into reference portfolio
created a report of potential tree damage to structure and provided design suggestions to mitigate damage
reviewed root plate assessment, prepared final report on stability of tree and provided design advice to mitigate potential tree failure
created an expert witness report on potential structure or tree stability
discussed installation and protection measures with project personnel
negotiated and resolved anomalies in installation and protection measures.
An individual must be able to demonstrate the knowledge required to perform the tasks outlined in the elements and performance criteria of this unit. This includes knowledge of:
impact of soil on the stability and structural integrity of structures and trees, including:
angle of repose of soil
soil plasticity
soil moisture content
field capacity of soil
effects of soil moisture on soil cohesion and plasticity
modes of soil liquefaction
testing soils for performance characteristics and soil stability, including:
soil texture
soil cohesion
soil moisture and field capacity
shear strength of soils
load bearing capacity
calculating mass of soil plate
tree root structures and their impact on soils and stability, including:
root morphology
root division
root distribution
buttressing
species development of tap root systems
identification of tree roots based on anatomical features
pressures exerted by tree roots, including:
experimental modelling of tree root damage
testing tree roots impact on structures and soils
direct and indirect forces and pressures exerted in soils by trees
techniques and methods of estimating and measuring dimensions of roots
factors of root–soil matrix interactions
area of contact between root and soil
elasticity of roots
tensile strength of roots
breaking stress of roots
root cross-sectional morphology
calculations for determining forces exerted by tree roots, including:
total surface area of the roots exerting forces on structures
forces exerted by roots per unit of surface area of structure
total force exerted by roots of a given surface area
measurement of volume of structures
calculating the mass of structures and the impact of gravity on mass
effect of leverage on the forces exerted by tree roots onto structure
tree root health and condition and impact on tree stability, including:
size of root plate and extent of root plate damage
extent of root plate deficiencies
extent of root plate defects
impact of static and dynamic testing for root plate stability
likelihood of root failure by root breakage and failure of root plate
likelihood of anchorage failure by soil breakage or slippage
considerations of structural design and development, and tree support to mitigate potential tree or structure damage, including:
effects of increasing mass of structure
effects of structure design and curvature of shape on strength of structures
effects of soil mass and friction
effects of increasing the modus of rupture
effects of use of tree support mechanisms
Australian standards relevant to trees on development sites
structure designs for mitigation of tree damage and failure
tree protection measures
creating reference portfolios of research and investigations, including annotations and calculations
documenting and reporting procedures, report preparation and communicating results of analysis, including:
test results and assumptions
expert witness reports, their purpose and design
using the correct language in reports and reporting
fundamentals of the concepts, basic science and technology of structural engineering, construction and architecture as relates to arboriculture and impact of trees on structures.
Assessment of the skills in this unit of competency must take place under the following conditions:
physical conditions:
a construction or development site with trees and structures or an environment that accurately represents workplace conditions
resources, equipment and materials:
computer with word processing software
digital imaging device
diagnostic tools, including sounding hammer, trowel, probe, cordless drill
soil testing equipment
digital dissection microscope 10x – 100x
compound microscope
microtome, staining and slide mounting equipment
specifications:
standard procedures and quality standards for performing soil analysis, tests and analysis on roots and structures
reference materials, reports and literature relevant to investigations and research into engineering, construction and architectural interactions with trees.
Assessors of this unit must satisfy the requirements for assessors in applicable vocational education and training legislation, frameworks and/or standards. In particular, assessors must have:
arboriculture vocational competencies at least to the level being assessed
current arboriculture industry skills directly relevant to the unit of competency being assessed.