ISO 15206:2010 材木柱—基本的な要件と試験方法 | ページ 6

3.1

bark pocket

bark that is partly or wholly enclosed in the wood

3.2

characteristic value

value corresponding to the 5th percentile of the statistical distribution of strength or the mean value of modulus of elasticity, at a 75 % confidence level

3.3

charge

all the wood treated together in one treatment at one time (one complete treatment cycle)

3.4

crack

separation of wood fibres across the grain

Note 1 to entry: These can be due to internal strains resulting from unequal longitudinal shrinkage, or the fibres being crinkled by compression or other external forces

3.5

critical zone

1,6 m length of pole measured from a point 1 m above the nominal ground line to 600 mm below the nominal ground line

Note 1 to entry: If the pole is nominated as a stayed pole, an additional zone measured from the top of the pole equivalent to the length between the nominal ground line and the butt of the pole shall be included.

3.6

decay

rot

decomposition of wood by fungi or other micro-organisms resulting in softening, progressive loss of mass and strength, and often a change of texture and colour

3.7

direct testing

testing the preservative treatment achieved by the direct measurement of the penetration and retention of preservative

3.8

double sweep

sweep characterized by two or more bends in one or several planes

3.9

fibre saturation point

FSP

state of a piece of timber when the cell walls are saturated with moisture but no moisture exists in the cell cavities

3.10

fissure

longitudinal separation of fibres

3.11

grain detector

device for detecting the angle of grain in timber

3.12

growth rate

mean number of growth rings per 25 mm

3.13

heart shake

radial end shake originating at the pith

3.14

incised zone

area of the lateral surface of the pole, which has undergone an incising process as an aid to securing deeper and more uniform penetration of preservative

Note 1 to entry: The minimum limit of the incised zone should be 400 mm above and 400 mm below the specified ground line for the pole in service.

3.15

included sapwood

presence in the heartwood of a complete or incomplete ring, having the colour and the properties of sapwood

3.16

indirect testing

testing the preservative treatment achieved by measurement of a property found to exhibit a correlation between itself and the penetration and retention of preservative

3.17

kerf

groove or slot formed in wood during the process of sawing

3.18

knot

portion of a branch embedded in wood

3.19

knot cluster

knots located such that no grain recovery is evident between adjacent knots

3.20

knot diameter

dimension of the knot measured on the surface of the pole and perpendicular to the axis of the pole

Note 1 to entry: The diameter takes the entire knot into account, including the sapwood.

3.21

length

distance from the pole butt to the pole tip

3.22

maximum diameter

largest diameter of the pole at the section of measurement

3.23

minimum diameter

smallest diameter of the pole at the section of measurement

3.24

moisture content

ratio of the mass of the quantity of water in a material to the mass of the dry material

3.25

nominal diameter

3.25.1

nominal diameter

theoretical diameter, usually the diameter measured at the nominal ground line

3.25.2

nominal diameter

minimum diameter

3.26

nominal ground line

plane normal to the axis of the pole usually located at a distance of 600 mm plus 10 % of the nominal length from the butt end

3.27

ovality

difference between the maximum and minimum diameter at a cross-section expressed as a percentage of the minimum diameter

3.28

pith

innermost part of the pole

3.29

pole

long, round timber for use in a free-standing application

3.30

pole butt

lowermost point of the thicker end of the pole

3.31

pole tip

uppermost point of the narrow end of the pole

3.32

population

group of poles defined by having the same species, source and grade

3.33

resin pocket

cavity that contains or has previously contained resin

Note 1 to entry: This may be similar to rind galls.

3.34

rind gall

surface wound that has been partially enclosed by the growth of a tree

3.35

ring shake

fissure following the line of a growth ring

3.36

sample

one or more poles taken from a single population

3.37

sampling unit

single preservative-treated pole taken from a charge

3.38

scribe

cranked rod with a swivel handle and a needle at the tip, set to a slight trailing angle

Note 1 to entry: This is used as a grain detector by pressing the needle into the timber and drawing it across the surface in the apparent direction of the grain.

3.39

section of maximum stress

section of pole where the diameter equals 1,5 times the diameter at the point of application of load if this section is above ground line; otherwise the actual ground-line section

3.40

short crook

local deflection

natural deviation of the axis of the pole occurring on a length less than 1,5 m

3.41

simple sweep

sweep characterized by one bend only

3.42

slope of grain

divergence of the direction of the fibres from the longitudinal axis of the piece

Note 1 to entry: The slope of grain in poles is usually observed as an inclination of the wood cells on the surface, which is referred to in some International Standards as spiral growth angle.

3.43

standard size pole

pole of a size 8 m or 10 m long and 180 mm to 220 mm diameter at 1,5 m from the butt end, and used for the determination of characteristic values

3.44

star shake

two or more heart shakes

3.45

sweep

deviation of the longitudinal axis of round timber from a straight line

3.46

taper

gradual reduction in diameter of a stem along its height or round timber along its length

3.47

theoretical diameter

diameter of a circle with the same circumference as the actual circumference at the section of measurement