1、- STD-BSI BS EN L3LO-ENGL 1997 II Lb24bb7 Ob37237 279 D BRITISH STANDARD Round and sawn timber - Method of measurement of features The European Standard EN 1310 : 1997 has the status of a British Standard ICs 79.040 BS EN 1310 : 1997 NO COPYING WiTHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGH
2、LAW BS EN 1310 : 1997 Amd.No. This British Standard, having been prepared under the direction of the Sector Board for Buiiding and Civil Engineering, was published under the authority of the Standards Board and comes into effect on 15 September 1997 Date Text affected O BSI 1997 ISBN O 680 28340 2 N
3、ational foreword This British Standard is the English language version of EN 1310 : 1997. The UK participation in its preparation was entrusted by Technical Committee W543, Round and sawn timber, to Subcommittee Bi543/1, limber terminology and measurement, which has the responsibility to: - aid enqu
4、irem to understand the text; - present to the responsible European committee any enquiries on the interpretation, or proposalc for change, and keep the UK interests informed - monitor related intemational and European developments and promulgate them in the UK. A list of organizations represented on
5、 this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled International Standards Correspondence Ind
6、ex, or by using the Find facility of the BSI Standards Electronic Catalogue. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 16, an inside back c
7、over and a back cover. Amendments issued since publication STD-BSI BS EN 1310-ENGL 1997 Lb211bb7 Ob37237 Ob1 EUROPEAN STANDARD NORNE EUROPENNE EuRopAIscHE NOM EN 1310 April 1997 ICs 79.040 Descriptors: Wood, sawlogs, sawn timber, appearance, defects, measurements English version Round and sawn mber
8、- Method of measurement of features Bois ron is the width on the minor axis, in millimetres; is the width on the major axis, in millimetres. Two methods for measuring knots are given: general method for appearance grading and alternative method where the strength of the piece is to be assessed. If s
9、trength grading is required, reference shall be made to EN 518 for visual grading and EN 519 for machine grading. When the standard is applied, it shall be stated whether the general or the alternative method is used O BSI 1997 STD-BSI BS EN L3LO-ENGL 1977 lb24bb9 Ob372Li2 b5b M Page 4 EN 1310 : 199
10、7 4.1.1 General method Consider each knot individually Measure knots on a part or ali the surface of the face) or the edge) as specified by the grading rule used. figures 1 to 6 show the categories of knots that shall be measured Each figure is accompanied by the corresponding formda that is generai
11、ly the arithmetic average of the width on the minor (a) and major (b) axis of the knot d = (a + b)L?. “hen measure the width on the minor and the major axes and derive the size hm the formula. NOTE. The maximum size of each kind of knot and the maximum number of these largest knots per piece or per
12、unit length is stated in the grading standards. For knots that are smaiier, a larger number may be permitted, but the sum of the sizes of such knots should not exceed the maximum permitted size multiplied by the maximum permitted number of the largest hots. See formula below. where d, + c d, 4, . d,
13、 are the sizes of the individual knots, in millimetres; 2 - On edges (knot B not measured, record its presence) Figure 3. Arris knot O BSI 1997 4.1.1.4 spike knot Depending on the grading rule used, a)usethefonnuhd=-;or b) not measured, record its presence. a+ b 2 Figure 4. Spike knot 4.1.1.6 Splay
14、knot Depending on the grading nile used, a) measure on the edge only and use the formula:d=-;or b) not measured, record its presence. a+b 2 Page 5 EN 1310 : 1997 4.1.1.6 Bramkd knot Depending on the grading nile used, a) not measured, record its presence; or b) record the number of knots in a unit o
15、f length. 4.1.1.7 Knot cluster Measure the individual knots. 4.1.1.8 Cats paw Measure the tota size of the knot cluster. a+b 2 FOKTUX d = - Figure 6. Cats paw * * Cn b 1 I I Figure 6. Splay knot O BSI 1997 STD-BSI BS EN L3LO-ENGL I997 mLb24bbS b37244 427 m Page 6 EN 1310 : 1997 4.1.2 Alternative met
16、hod This method is not used for wedged timber. Consider knots only on a face andor an edge where they appear cut transversely or obiiquely figures 7 to 12 show the categories of knots that shall be measured. The size shall be the width of the knot or knot cluster, measured at right angles to the lon
17、gitudinal axis of the piece. 4.1.2.1 Round knot Figure 7. Round knot 4.1.2.2 Oval kmt 1 I C A B 2 I ml D 1 - On faces; 2 - On edges Figure 8. Oval knot E F O BSI 1997 STD-BSI BS EN 1310-ENGL 1997 Lb24bb7 Ob37245 3b5 Page 7 EN 1310 : 1997 4.1.2.3 Arris mot KNOT A KNOT B 1 - On faces; 2 - On edges (kn
18、ot B: not measured, record its presence) Figure 9. Arris knot 4.1.2.4 Spike mot Figure 10. Spike knot 4.1.2.6 Spuy knot Measure on the edge where it has been tmnwemly cut. 4.1.2.6 Brunched knot Measure on the edge, see 4.1.2.6 and figure 11. 2 I 1 - On faces; 2 - On edges Figure 11. Splay knot O BSI
19、 1997 STDOBSI BS EN 1310-ENGL 1977 m LbZqbbS Ob392qb 2TL Page 8 EN 1310 : 1997 4.1.2.7 Knot cluster Knots are measured on the surface on which they are transvercely cut. The size d sha be the overail width of the knot cluster (figure 1% measure d), or the sum of the sizes of the individual knots (fi
20、gure 12B), where whichever is less. 4.2 Resin pocket Dependmg on the gradmg rule used, d = dl + d2 + . + d, a) measure the major axis of the resin pocket, expressed in millimetres. If more than one, also record their number per metre length of the piece or for the full length of the piece; or b) not
21、 measured, record its presence. 4.3 Reaction wood Depending on the gradmg nile used, a) measure the length and/or the width of a rectangle that encloses it, expressed in centimetres or as a percentage of the length ancUor the width of the surface (face or edge) being considered. Where there are two
22、or more areas of reaction wood, each shail be measured as before, and the respective dimensions totalled; or b) not measured, record its presence. 4.4 Grain 4.4.1 Slope of grain Use a scribe to determine slope of grain. A scribe is shown in figure 13.1. It consists of a cranked rod with a swivel han
23、dle at one en4 a needle set to a slight tsailllig angle at the other. If the scribe is drawn along the piece of timber in the apparent direction of the grain, applying sufficient but not excessive pressure, it will scribe a line that shows accurately the direction of grairi. To check, it is recommen
24、ded to draw several adJacent lines, with the direction of pull diverging slightly to the left and to the right; the scribe should still follow the correct direction (see figure 13.2). Express the result as a percentage, using the formuh X - x 100 Y where x is the deviation of the grain, in millimetr
25、es; y is the length over which the measurement is taken, in millimetres. d B d3 A Figure 12. Knot cluster B O BSI 1997 STD-BSI BS EN 13LO-ENGL 1777 1b24bb7 0b37297 238 Page 9 EN 1310 : 1997 Figure 13.1 Scribe I 1 X J I Y I Figure 13.2 Use of a scribe 4.4.2 Spiral, interlocked grain Not measured, rec
26、ord its presence. 4.4.3 Curly grain Depending on the gmhg rule used, a) measure the length and/or the width of a rectangie that encloses it, expressed in centimetres or as a percentage of the length andor the width of the surface (face or edge) being considered. Where there are two or more areas of
27、curly gram, each shall be measured as before, and the respective dimensions totalled or b) not measured, record its presence. 4.6 Rate of growth On one end of the piece, mark out the longest possible straight line nomd to the growth rings. Count the number of growth rings along this he. Repeat at th
28、e other end of the piece. Disregard the portion, if any, within 25 mm of the pith. Divide the sum of the lengths of the two lines at the two ends by the total number of growth rings counted to obtain the rate of growth, expressed as the average width of the growth rings in millimetres (see figure 14
29、). O BSI 1997 STD=BSI BS EN L3LO-ENGL 1797 Lb24bb7 Ob372Li8 O74 Page 10 EN 1310 : 1997 I A B C Figure 14. Rate of growth D 4.6 Bark pocket Depending on the grading rule used, a) measure the length and/or the width of a rectangle that encloses it, expressed in centimelxes or as a percentage of the le
30、ngth and/or the width of the surface (face or edge) being considered. Where there are two or more areas of bark pocket, each shaU be measured as before, and the respective dimensions totalled; or b) record the number of bark pockets over one metre length or over the length of the piece; or c) not me
31、asured, record its presence. 4.7 Sapwood Depending on the grading rule used, a) find that portion of the surface (face or edge) being considered where the sapwood is widest. Measure the width and express the result in millimetres or as a percentage of the width of the surface; or b) not measured, re
32、cord its presence. 4.8 Wane Depending on the grading rule used, a) measure the length (c) of wane and express it in centimetres or as a percentage of the length. If wane shows on more than one part of the arris, add the dierent lenh (CI. c. . . . m). see firne 15: or Figure 16. Wane O BSI 1997 b) me
33、asure the greatest width of the wane on the face or edge and express the result in millimetres, or dternaiively, as a decimal fraction using the following formulae: a - a1 wf=- a b - 61 We=b where wf is the width of the wane on the face, as a decimal fractioq we is the width of the wane on the edge,
34、 as a decimal fraction; a is the full width of the face, in millimetres; al is the width of the face when reduced by the wane, in millimetres; b is the full width of the edge, in millimetres; bl is the width of the edge when reduced by the wane, in millimetres, see figure 15; or c) not measured, rec
35、ord its presence. 4.9 Fissure 4.9.1 Face, edge and end shakes, splits Depending on the graduig nile used, a) measure its length by determining the distance between two lines normal to the longitudinal axis of the piece and passing through the ends of the fissure. For a cluster of fissures, measure t
36、he overall Page 11 EN 1310 : 1997 length of the cluster. If there are severai fissures or clusters, total their length. Express the result in miiiimetres or as a percentage of the length of the piece; or b) not measured, record their presence. 4.9.2 Ring and heart shakes If showing only at one or bo
37、th ends of the piece, record their presence. If showing on a face or edge, measure as in 4.9.1. 4.9.3 Checks Depending on the grading rule used, a) measure the length andor the width of the rectangle that encloses the portion where they occur, expressed in millimelxes or as a percentage of the lengt
38、h andlor width of the surface (face or edge) being considered; or b) record their presence. 4.10 Warp 4.10.1 Bow and spring Measure the maximum distortion hm the stmight: a) for pieces up to a length of 2 m, applying a stsaight edge, expressing the result in millimetres; b) for pieces longer than 2
39、m, over a 2 m length, using a 2 m long rigid straight edge applied against the piece symmetrically at the point of maximum distortion, visually estimated. Express the result in millimetres per 2 m (see dimension w in figure 16 and dimension x in figure 17). Figure 16. Bow I Figure 17. Spring O BSI 1
40、997 STD-BSI BS EN 1310-ENGL 1977 Lb24bb7 Ob37250 722 Page 12 EN 1310 : 1997 4.10.2 Cup Measure the maximum distortion in the width of the piece, expressed in millimetres or as a percentage of the width. See dimension z in figure 18. Figure 18. Cup 4.10.3 lhist Measure the maximum distortion of the s
41、urface over a representative 2 m length, expressed in millimetres or as a percentage of the length of the piece. See dimension y in figure 19. 5 Round timber 6.1 Knots 6.1.1 Uncovered knot Measure, close to the curved surface of round timber, the smaiier diameter of the knot. Express the result in m
42、illimetres. Disregard the surrounding dus. 6.1.2 Covered knot Not measured, record its presence. 6.1.3 Rose Depending on the grading rule used, a) measure the smaller diameter of the outer complete concentric ring, expressed in millimetres; or b) not measured, record its presence. 6.1.4 Epicormic sh
43、oot Not measured, record its presence. 6.1.6 Burl Not measured, record its presence. 6.1.6 Chinese moustache Depending on the grading rule used, a) measure the height of the arc drawn on the surface, expressed in millimetres; or b) not measured, record its presence. 6.2 Fissures 6.2.1 Heart shake De
44、pending on the grading rule used, a) measure the length of the fissure visible on one end surface of round timber starting from the pith, expressed in miilimetres; or b) not measured, record its presence. 6.2.2 Star shake Depending on the grading rule used, a) measure the length of the longest fissu
45、re visible on the end surface of round timber starting from the pith, expressed in millimetres; or b) not measured, record its presence. 6.2.3 Ring shake Depending on the grading rule used, a) measure the diameter of the circle of which the ring shake is an arc, expressed in millimetres or as a perc
46、entage of the diameter of round timber; or b) not measured, record its presence. 6.2.4 Frost crack, lightning shake Depending on the grading rule used, a) measure its length, expressed in centimebe or as a percentage of the length of round timber. If more than one, total their length; or b) not meas
47、ured, record its presence. 6.2.6 Check, traversing crack Not measured, record its presence. 6.2.6 Felling shake Measure its length, expressed in centimetres or as a percentage of the length of round timber. Figure 19. %ist O BSI 1997 - STD-BSI BS EN 1310-ENGL 1797 LbZLibbS Ob39251 bb7 Page 13 EN 131
48、0 : 1997 6.3 Sweeps 6.3.1 Simple sweep If conditions permit, measure the maximum distance between the messed concave centre he of the log and a straight line joining the centres of each end, expressed in centimetres per metre length of the log (see figure 20A). If the above method is not possible, m
49、easure the maximum distance between the rounded concave surface and a straight he joining the innermost points of the end surfaces (see figure 20B). 6.3.2 Multiple sweep Divide the log with theoretical crosscut points into straight or simple sweep portions. Measure each porjon as specified in 6.3.1 above (see figures 2iA and 21B). Record each value separately in centimetres per meire length of the portion. A B A) Centre line measure B) Surface measure Figure 21. Multiple sweep A B Figure 20. Simple sweep A) Centre line measure B) Surface mea
