3.2 Glossary
3.2 Glossary
Acceleration The rate of change of speed of an object . Adaptive growth The growth of new wood in response to a concentration of strain in the structure of a tree . Anchor In rigging or climbing , the point where the rope is tied off or where friction is controlled . Anchor block
In a mechanical advantage system that employs pulleys , the stationary block in a block and tackle system .
Anchor force The sum of the forces acting upon the anchor point / s in a rigging system . ANSI United States standard . See Australian / New Zealand and International Standards . Arboriculture Arborist
Arc flash
AS / NZS
Australian / New Zealand and International Standards
Axiom of uniform stress
The practice and study of the care of trees and other woody plants in the landscape
A professional worker who through formal training and experience is competent to perform arboricultural works .
Arc flash occurs where an electrical current flows through an air gap between two conductors or between a conductor and the ground . It can cause a heat and shock wave .
Australian / New Zealand standard . E . g .: AS / NZS 1336-2014 Recommended practices for occupational eye protection . See Australian and International Standards .
Standards are documents that set out specifications , procedures and guidelines that aim to ensure products , services , and systems are safe , consistent , and reliable .
The theory that the growth of new wood in trees tends to eliminate any stress concentrations in the tree structure , maintaining a uniform stress distribution .
Axis or axes ( of loading ) A direction in which a component can be loaded . Back cut
Barber ’ s chair
The last in a series of cuts used in felling or limb removal , made on the opposite side of a log toward the scarf .
Dangerous condition created when a tree or branch splits longitudinally ( vertically ) up from the back cut .
Bark The outermost layers of trees and woody plants . Basal anchor
Where a pulling rope is passed through a suspension point in the crown , then tied off to an anchor at ground level .
Becket A secondary attachment point on a pulley . Belay device A piece of equipment used to provide friction for belaying a climber . Bend radius The radius of an object around which a line passes . Bend ratio
Bending moment
The ratio of the diameter of a branch , sheave or other device to the diameter of the rope that is wrapped on it .
The amount of turning force applied at a given point in a structure . Measured in Newton metres or Nm .
Bight |
A curve or arc in rope . |
Block |
A pulley used in rigging , designed for dynamic loading . |
Bollard |
A post on which wraps can be taken with a rope to increase friction . |
Branch attachment |
The point at which a branch is anchored into the parent stem . |
Branch : stem aspect ratio
The ratio of the diameter of the branch and the diameter of the parent stem . Expressed , for example , as 1:2 or as a decimal ( 0.5 ).
Breaking strength |
The force at which a piece of equipment or rope fails under a static load . |
Canopy anchor |
Where a rope is tied off to the tree ’ s structure in the crown . |
Cavity |
An open wound or hollow within a tree , usually associated with decay or damage . |
Co-dominant stems |
Competing stems which have usually originated from the same bud . |
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