Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
MALAYSIAN STANDARD
MS 544 : PART 5 : 2001
CODE OF PRACTICE FOR STRUCTURAL USE OF TIMBER : PART 5 : TIMBER JOINTS
ICS : 91.080.20 Descriptors :
permissible stress design, timber joint, solid timbe fabricated with mechanical fasteners, joint groups, timber grade, working loads, permissible loads, spacing, edge, end distances
© Copyright DEPARTMENT OF STANDARDS MALAYSIA
DEVELOPMENT OF MALAYSIAN STANDARDS The Department of Standards Malaysia (DSM) is the national standardisation and accreditation body.
The main function of the Department is to foster and promote standards, standardisation and accreditation as a means of advancing the national economy, promoting industrial efficiency and development, benefiting the health
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
and safety of the public, protecting the consumers, facilitating domestic and international trade and furthering international cooperation in relation to standards and standardisation.
Malaysian Standards are developed through consensus by committees which comprise of balanced representation of producers, users, consumers and others with relevant interests, as may be appropriate to the subject in hand. These standards where appropriate are adoption of international standards. Approval of a standard as a Malaysian Standard is governed by the Standards of Malaysia Act 1996 (Act 549). Malaysian Standards are reviewed periodically. The use of Malaysian Standards is voluntary except in so far as they are made mandatory by regulatory authorities by means of regulations, local by-laws or any other similar ways.
The Department of Standards appoints SIRIM Berhad as the agent to develop Malaysian Standards. The Department also appoints SIRIM Berhad as the agent for distribution and sale of Malaysian Standards.
For further information on Malaysian Standards, please contact: Department of Standards Malaysia OR Level 1 & 2, Block C4, Parcel C Federal Government Administrative Centre 62502 Putrajaya Malaysia
SIRIM Berhad 1, Persiaran Dato' Menteri P.O. Box 7035, Section 2 40911 Shah Alam Selangor D.E.
Tel: 60 3 88858000 Fax: 60 3 88885060 http://www.dsm.gov.my
Tel: 60 3 5544 6000 Fax: 60 3 5510 8095 http://www.sirim.my
Email:
[email protected]
MS 544: PART 5 : 2001
CONTENTS
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
Page Committee representation
iv
Foreword
vi
1
Scope
1
2
Referenced documents
1
3
Joint groups
2
4
Timber grade
3
5
Anti-corrosion treatment
3
6
Tendency to split
3
7
Eccentric joints
4
8
Shear stress in the jointed member
4
9
Nailed joints
5
10
Screwed joints
12
11
Bolted joints
15
12
Coach screws
25
13
Split-ring connectors
28
14
Shear plate connectors
37
Tables 1
Group classification of timbers for use in joint design
2
2
Dry basic single shear lateral loads for one nail inserted at right angles to side grain
5
3
Dry basic single shear lateral loads for one nail in a plywood to timber joint
6
4
Modification factor k1 for duration of loading for different fasteners
9
MS 544: PART 5 : 2001
CONTENTS (continued)
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
Page 5
Values of factor k17 for use in the design of multiple nail and screw joints
9
6
Minimum spacing, edge and end distances for nails
10
7
Basic withdrawal loads for one nail inserted at right angles to side grain
11
8
Dry basic single shear lateral loads for one wood screw inserted at right angles to side grain 12
9
Minimum spacing, edge and end distances for screws
10
Dry basic withdrawal loads for one wood screw inserted at right angles to side
13
grain
14
11
Maximum permissible withdrawal load per screw
14
12
Dry basic loads for one bolt in single shear
16
13
Basic working loads for a bolted joint system loaded parallel to grain
18
14
Basic working loads for a bolted joint system loaded perpendicular to grain
19
15
Values of factor K17 for use in the design of multiple connector joints of bolts, coach screws, split ring and shear plates
21
16
Minimum required size of washers for structural bolted joints
24
17
Design parameters for bolts under axial load
24
18
Dry basic withdrawal loads for coach screws in side grain
27
19
Maximum permissible withdrawal loads per coach screws
27
20
Sizes of split-ring connectors and minimum sizes of washers
28
21
Dimensions of circular grooves for split-ring connectors
29
22
Dry basic loads for one split-ring connector unit
30
MS 544: PART 5 : 2001
CONTENTS (continued)
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
Page 23
End distances for split-ring and shear-plate connectors
32
24
Edge distances for split-ring and shear-plate connectors
32
25
Spacing modification factor, k~,for split-ring and shear-plate connectors
33
26
End distances modification factor, k~,for split-ring and shear-plate connectors
35
27
Loaded, edge distances modification factor, kD, for split-ring and shear-plate connectors
36
28
Sizes of shear-plate connectors and minimum sizes of washers
37
29
Dry basic loads for one shear-plate connector unit
40
30
Limiting values for permissible loads on one shear-plate connector unit
41
Figures 1
Shear stress in the jointed member
4
2
Illustration of a longitudinal and rotational joint
8
3
Graph of Hankinson formula
20
4
Spacing, edge and end distances for bolted joints
23
5
Coach screw
26
6
Timber thicknesses and fastener lengths for coach screws
26
7
Spacing, edge and end distances for split-ring and shear-plate connectors
36
8
Dimension of circular recesses for shear-plate connector units conforming to BS 1579
38
III
MS 544: PART 5: 2001
Committee representation
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
The Building and Civil Engineering Industry Standards Committee (ISC D) under whose supervision this Malaysian Standard was developed, comprises representatives from the following Government Ministries, Trade, Commerce and Manufacturing Associations, and Scientific and Professional Bodies: Association of Consulting Engineers Malaysia Construction Industry Development Board Malaysia Department of Standards Malaysia Department of Occupational Safety and Health Jabatan Bornba dan Penyelamat Pertubuhan Akitek Malaysia Master Builders Association Malaysia Ministry of Housing and Local Government (Housing Department) Ministry of Works (Public Works Department) The Institution of Engineers, Malaysia Universiti Teknologi Malaysia The development of this Malaysian Standard is under the supervision of the following representatives of the CIDB Standard Committee: Ir. Mohamed bin Mohd Nuruddin Megat Kamil Azmi bin Megat Rus Kamarani Puan Zainora bt Zainal Puan Hanishahani Othman
General Manager Technology Development Division Senior Manager Standard and Quality Unit Manager Standard and Quality Unit The Secretary of CIDB Standard Committee
The Technical Committee on Structural Use of Timber which developed this Malaysian Standard consists of the following representatives: Dr. Abdul Rashid bin H]. Ab. Malik (Chairman)
Forest Research Institute Malaysia
Puan Hanishahani Othman (Secretary)
Construction Industry Development Board Malaysia
Tuan Hj. Mohd Shukari bin Midon
Forest Research Institute Malaysia
Encik Hilmi bin Md. Tahir
Jabatan Kerja Raya Malaysia
Encik Chow Wah/ Puan Dang Anom Md. Zin
Jabatan Perumahan Negara
Prof. Madya Dr. Sabaruddin bin Mohd.
Universiti Sains Malaysia
Prof. Dr. Zainai bin Mohamed/ Dr. Abd. Latif bin Saleh
Universiti Teknologi Malaysia
Prof Madya lr. Dr. Mohd Zamin bin Jumaat
Universiti Malaya
Dr. Mohd Ariff bin Jamaludin
Universiti Putra Malaysia
Encik Mohd Nor Zamri bin Mat Amin
Malaysian Timber Industry Board
Ir. Yap Chin Tian
Timber Trade Federation Malaysia
Tuan H]. Wahab bin Abdul Razak.
General Lumber Fabricators and Builders Bhd
Dr. Peter Kho Chin Seng
Sarawak Timber Association
Encik Lall Singh Gill
Malaysian Wood Moulding and Joinery Council
Encik Mohamad Omar bin Mohamad Khaidzir
Forest Research Institute Malaysia
iv
MS544: PART5: 2001
Committee representation (continued) The Working Group on Timber Joints which developed this Malaysian Standard consists of the following
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
representatives: Tuan H]. Mohd Shukari bin Midon (Chairman)
Forest Research Institute Malaysia
Puan Hanishahani Bte Othman (Secretary)
Construction Industry Development Board Malaysia
Encik Hilmi bin Md. Tahir
Jabatan Kerja Raya Malaysia
Ir. Yap Chin han
Timber Trade Federation Malaysia
Dr. Peter Kho Chin Seng
Sarawak Timber Association
Mr. Nicolas Roulant
General Lumber Fabricators and Builders Bhd
Prof. Madya Ir. Dr. Mohd Zamin bin Jumaat
Universiti Malaya
Dr. Mohd. Ariff bin Jamaludin
Universiti Putra Malaysia
YM. Engku Abdul Rahman bin Chik
Syntek Sdn. Bhd
Encik Chu Yue Pun Encik Mohd Nor Zamri bin Mat Amin
Malaysian Timber Industry Board
V
MS544: PART 5:2001
FOREWORD This Malaysian Standard was developed by the Technical Committee on Structural Use of Timber established at the Construction Industry Development Board Malaysia (CIDB) under the authority of the Building and Civil Engineering Industry Standards Committee. 01DB is the Standards-Writing Organisation (SWO) appointed by SIRIM Berhad to develop standards for the construction industry. In the development of this standard, the following references were referred to:
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
a)
BS 5268: Part 2: 1996, Code of practice for permissible stress design, materials and workmanship; and
b)
AS 1720.1-1 988, SAA Timber structures code: Part 1
-
Design methods.
MS 544 consists of the following parts and sections, under the general title, ‘Code of practice for structural use of timber’ Part 1
:
General
Part 2 :
Permissible stress design of solid timber
Part 3 :
Permissible stress design of glued laminated timber
Part 4 :
Timber panel products Section 1: Structural plywood Section 2: Marine plywood Section 3: Cement bonded particleboard Section 4: Oriented strand board
Part 5 :
Timber joints
Part 6 :
Workmanship, inspection and maintenance
Part 7 :
Testing
Part 8 :
Design, fabrication and installation of prefabricated timber for roof trusses
Part 9 :
Fire resistance of timber structures Section 1 : Method of calculating fire resistance of timber members
Part 10 :
Preservative treatment of structural timbers
Part 11 :
Recommendation for the calculation basis for span tables Section 1 : Domestic floor joists Section 2 : Ceiling joists Section 3 : Ceiling binders Section 4: Domestic rafters
Part 12 :
Laminated veneer lumber for structural application.
Compliance with a Malaysian Standard does not of itself confer immunity from legal obligations. Vi
MS544: PART5: 2001
CODE OF PRACTICE FOR THE STRUCTURAL USE TIMBER: PART 5 : TIMBER JOINTS 1.
Scope
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
This part applies to joints in solid timber fabricated with mechanical fasteners described by Malaysian Standard. These include joints fabricated with the following mechanical fasteners: a) b) c) d) e) f)
nails; wood screws; bolts; coach screws; split-ring connectors; and shear-plate connectors.
NOTES:
1. Design rules for specialised and patented mechanical fasteners and for variants of conventional fasteners are not included in this code. 2. This Standard doe.s not specifically cover glued timber-to-timber or timber-to-plywood connections as occurred in fabricated components such as stressed skin panels or plywood webbed beams. In such cases, joint design can be based on the timber components in the connection, provided that the joint is fabricated using a rigid, durable adhesive. Phenolic type adhesives meet these requirements. The design of fabricated components comprising glued connections is therefore based on the fact that with correct bonding practice and quality control, a joint is developed in which the adhesive bond strength and durability will be superior to the components comprising the joint. Reference may be made to AS 1720.1: 1988, Appendix D2 for information on methods for assessing the deformation of joints.
2.
Referenced documents
The following referenced documents contain provisions which, through reference in this text, constitute provision of this Malaysian Standard. For dated references, where there are subsequent amendments to, or revisions of, any of these publications the Malaysian Standard shall be amended or revised accordingly. For undated references, the latest edition of the publication referred apply. MS 544: Part 2: Permissible stress design of solid timber MS 544 : Part 4: Timber panel products: Section 1: Structural plywood Section 2: Marine plywood NZS 3603: 1981 Code of practice for timber design : Section 4 Joints —
Timber design handbook-Malaysian Forest Record No. 42 FRIM -
Structural timber joints-Malaysian Forest Record No. 32 FRIM -
AS 1393
Coach screws (metric series) (with ISO hexagon heads)
AS 1476
Metric wood screws
AS 2334
Steel nails Metric series -
1
MS 544: PART5: 2001
Products grade C
AS 1111
ISO metric hexagon bolts and screws
BS 373
Methods of testing small clear specimens of timber
BS 1579
Connectors for timber
ASTM D143
Standard methods of testing small clear specimens of timber
—
Air seasoning properties of some Malaysian timbers -Malaysian Forest Service Trade Leaflet No.41 MTIB -
The strength properties of some Malaysian timbers Malaysian Forest Service Trade Leaflet No. 34- MTIB Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
-
3.
Joint groups
For the purpose of joint design, timber species have been classified into five joint groups: Ji, J2, J3, J4 and J5. The joint group classifications for specific timbers are shown in Table 1. Table 1. Group classification of timbers for use in joint design Joint group
Strength group
Timbers
J1
SG1
Balau
J2
SG2/ SG3
Agoho Dedaru Kelat Merbatu Pauh kijang Ranggu
J3
504
J4
J5
Bitis
Chengal
Penaga
Bekak Delek Kembang semangkok Mertas Penyau Tualang
Belian Kern pas Kekatong Mata ulat Petaling
Balau, red Keranji Kulim Perah Surian batu
Berangan Kapur Malabera Meransi Merpauh Rengas
Dedali Kasai Meranti bakau Nyalin Resak
Derum Keruntum Merawan Perupok Simpoh
Giam Mempening Merbau Punah
SG5
Alan bunga Brazil Nut Kungkur Meranti, dark red Meranti white Ramin Tembusu
Babai Gerutu Kelendang Melunak Nyatoh Rubberwood Teak
Balik angin bopeng Kedondong Keruing Mempisang Petai Sepetir
Biritangor Kayu kundur Ketapang Mengkulang Penarahan Sen gkuang
SG6/ SG7
Ara Damar minyak Jenitri Machang Mersawa Terap
Bayur Geronggang Kasah Medang Pelajau Terentang
Batal Jelutong Laran Melantai/ Kawang Pulai
Durian Jongkong Meranti, light red Meranti ,yellow Sesendok
2
MS 544: PART 5 : 2001
Where joints comprise more than one species of timber, the design load to be used in the absence of other information is that appropriate to the weakest species in the joint.
4~
Timber grade
No allowance for the various grade of timber has been made in design data for fasteners. Design loads for joints have been based on the assumption that there are no loose knots, severe sloping grain, gum veins, gum or resin pockets, pith, holes or splits near any fastener. Accordingly, all of these defects shall be avoided at fastener locations.
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
5.
Anti-corrosion treatment
The loads specified for nails, screws, bolts and coach screws apply to fasteners that are not treated against corrosion. Some forms of anti-corrosion treatment may affect fastener performance. The loads specified for timber connectors apply to fasteners that are treated against corrosion. Fasteners used in wet timber or in timber, which will be exposed to the wet exposure condition, should be non-corrodable or are treated by an anti-corrosive process.
6.
Tendency to split
Special precautions shall be specified in the use of timber that has a tendency to split to an extent that may be detrimental to connector strength. In the absence of other guidance, the criterion for tendency to split shall be based on the parameter cx defined by:
where, c
is the tangential shrinkage, in %; and
y
is the tangential cleavage strength of green timber, in Newton per millimetre (N/mm), as measured by BS 373 or ASTM D143.
Species for which cx > 0.8 often have a high tendency to split, particularly in exposed locations; species for which cx < 0.55 may be considered to have a negligible tendency to split. NOTES: 1. Information on shrinkage and cleavage for specific species can be obtained from the following: a) Malaysian Forest Service Trade Leaflet No: 41: Air-seasoning properties of some Malaysian timbers. b) Malaysian Forest Service Trade Leaflet No: 34: The strength properties of some Malaysian timbers. 3 2. It will be found that most hardwoods that have a basic density of less than 700 kg/m will have splitting parameter c~> 0.8; most rainforest hardwoods of higher density have a splitting parameter a < 0.8.
3
MS 544: PART5 :2001
7.
Eccentric joints
When it is impracticable to ensure that all the members meeting at a joint are arranged symmetrically, with their centrelines intersecting on a common axis which is also the axis of resistance of the fasteners or group of fasteners, the combined effects of primary stresses and secondary stresses due to the resulting bending and shear stress shall be checked.
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
8.
Shear stress in the jointed member
The effective cross-section of a jointed member should be used when calculating its strength. The method of determining the effective cross-section is given in the appropriate clauses for each type of fastener. In addition, it should be shown that the shear stress condition shown in Figure 1 is satisfied in the jointed member.
Unloaded edge
hI
Figure 1. Shear stress in the jointed member V
=
Fsina
3V shall not exceed ‘C
adm
2 bhe where, V is the shearing force at the section; B is the thickness of the member;
4
MS544: PART5 :2001
he
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
‘C
is the depth of member less the distance from the unloaded edge to the centre of the bolt (see Figure 1); and
adm
permissible shear stress as given by MS 544: Part 2.
9.
Nailed joints
9.1
Lateral loads
9.1.1
Basic working loads
The basic working loads for plain shank, low carbon steel nails specified in AS 2334 or equivalent whether driven by hand or by gun, in single shear in timber fabricated in the dry condition is given in Table 2. For plywood to timber joints the basic working loads are given in Table 3. A nailed joint should normally contain at least two nails. In general, the species in joint groups Ji and J2 of Table 1 require to be pre-drilled. Driving nails into holes pre-drilled to a diameter slightly less than the diameter of the nail results in a small increase in the holding power. The diameter of the pre-drilled holes should not be greater than four-fifths of the diameter of the nail. Table 2. Dry basic single shear lateral loads for one nail inserted at right angles to side grain Diameter of nail
Standard thickness of members (mm)
Basic lateral load (N) for timber in joint group:
(mm)
SWG
Head side
Point-side
Ji
J2
J3
J4
J5
2.0
14
13
19
248
197
158
126
99
2.3
13
16
22
310
246
197
157
123
2.6
12
19
25
377
300
239
191
150
3.0
11
22
29
473
375
300
240
188
3.3
10
25
32
551
437
350
280
219
3.7
9
29
38
660
523
419
335
262
4.1
8
32
44
779
618
495
395
309
4.5
7
38
51
900
715
572
457
359
4.9
6
44
57
1035
822
657
526
411
5.4
5
51
67
1205
958
767
613
480
5.9
4
57
76
1390
1103
882
703
555
6.4
3
64
89
1575
1250
1000
801
626
5
MS 544: PART 5 : 2001
Table 3. Dry basic single shear lateral load for one nail in a plywood to timber joint
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
Nominal” plywood thickness
Nail (mm)
Penetration of nail to timber~(mm)
Basic Lateral load (N) for timber in group
~_________
(mm)
Diameter
Minimum length
Standard
Minimum
JI
J2
J3
J4
J5
6
2.6 3.0 3.3 3.7 4.1
40 45 45 55 60
34 39 39 49 55
13 15 17 19 21
339 426 496 594 701
270 337 393 471 556
215 270 315 377 445
172 216 252 301 355
135 169 197 236 278
9
2.6 3.0 3.3 3.7 4.1
40 45 45 55 60
31 36 36 46 51
13 15 17 19 21
342 429 494 597 704
273 340 396 474 559
218 273 318 380 448
175 219 255 304 358
138 172 200 239 281
12
2.6 3.0 3.3 3.7 4.1
40 45 45 55 60
28 33 33 43 48
13 15 17 19 21
345 432 502 600 707
276 399 477 562
221 276 321 383 451
178 222 258 307 361
141 175 203 242 284
2.6 3.0 3.3 3.7 4.1
40 45 45 55 60
25 30 32 40 45
13 15 17 19 21
348 435 505 603 710
279 346 402 480 565
224 279 324 386 454
181 225 261 310 364
144
178 206 245 287
18
2.6 3.0 3.3 3.7 4.1
43 47 50 56 62
25 29 32 38 44
13 15 17 19 21
351 438 508 606 713
282 349 405 483 568
227 282 327 389 457
184 228 264 313 367
147 181 209 248 290
21
2.6 3.0 3.3 3.7 4.1
46 50 53 59 65
25 29 32 38 44
13 15 17 19 21
354 441 511 609 716
285 352 408 486 571
230 285 330 392 460
187 231 267 316 370
150 184 212 251 293
15
343
NOTES: 1. Plywood should be structural or marine plywood depending on service condition, see MS 544: Part 4: Section 1 and 2. 2. The basic load is based on the standard nail penetration, If the penetration is less than the standard but not less than the minimum, the basic load should be reduced proportionately. If the penetration is more than the standard, no increase in basic load is allowed.
6
MS 544: PART5:2001
9.1.2
Permissible loads
The permissible load Fadm
-
Fadm
of a laterally loaded nail shall be taken to be given by:
k1 k2 k13 k14 k16 k17 F
where; k1
=
k2
= =
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
=
k13
= =
k14
= =
= =
k17
=
the factor for duration of load given in Table 4; 1.0 for dry timber 1 .0 for annular ring shank and helical threaded shank nails under all exposure conditions 0.7 for wet timber; 1.0 for nails in side grain 0.7 for nails in end grain; 1.0 for nails in single shear 0.9 times the numbers of shear plane, provided that each of the member in a multiple shear joint has a thickness of not less than 0.7 of the standard thickness for point side member given in Table 2; 1.25 for nails driven through close fitting holes into metal side plates 1 .0 for timber to timber joint; factor for multiple nailed joints given in Table 5.1 for longitudinal joints and Table 5.2 for rotational joints; and
F
=
basic working load given in Table 2.
For longitudinal joints containing n nails, F~,the design load capacity of the joint, shall be taken to be given by =
nFadm
For rotational joints containing n nails, M~,the design in-plane moment capacity of the joint, shall be taken to be given by n M~
=
Fadmrmax~
(rj/rma,~f’2
1=1 where; r,
is the distance from the P~nail to the centroid of the nail group; and
rmax
is the maximum value of r1
Longitudinal and rotational joints are illustrated in Figure 2.
7
MS 544: PART5:2001
7
~aI
Fn~
•
••••
•
• •
•
• ••
•
•
• • •
•
~.
• ••
F,~
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
(a) Longitudinal joint
Circle of radius 0.7 r M~ .‘ I •,i.
• •
•‘~.
•
II I I I I I
•
N
• ~
~ •~‘
‘
—~‘~
r max na= 14
k~i
(b) Rotational joint Figure 2. Illustration of a longitudinal and rotational joint
8
MS 544: PART5:2001
Table 4. Modification factor k1 for duration of loading for different fasteners
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
Fastener
Duration of loading Long term
Medium term
Short and very short term
Nails and screws
1.0
1.125
1.25
Bolts, coach screw, split-rings and shear- plates
1.0
1.25
1.5
Table 5. Values of factor k17 for use in the design of multiple nail and screw joints (Comprising of Table 5.1 and 5.2) Table 5.1. For longitudinal tension joints Value of 1c17 Condition of timber
•
Fasteners flal
Wet
flat
1.00 1.00
ry NOTE.
4
5
0.90 0.94
fla;
= 10
flal
0.80 0.90
0.75 0.85
number of fasterners in each row per interface. See Figure 2(a)
flaf
Table 5.2. For rotational joints flar =
k
number of nails per interface
17
1.00 1.05 1.10 1.15 1.20
2 5 10 20 100 or greater NOTES: fla
=
number of nails within the circle of radius 0.7 rmax
r,
=
distance from fth nail to centroid of nail group
rmax
=
maximum value of r
1
See Figure 2 (b).
9
20
MS544: PART5:2001
9.1.3
Spacings, edge and end distances
Table 6 provides recommended minimum spacings, edge and end distances for nails in terms of nail diameter d. For spacings at an angle to the grain, interpolation by means of Hankinson’s formula may be used. NOTE. For timber that has a tendency to split (see Clause 6) some mitigation measures such as pre-drilling or increased spacing are recommended. The fabrication of prototype joints is a useful method of checking the efficacy of mitigation measures.
Table 6. Minimum spacing, edge and end distances for nails
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
Spacing type
Minimum distance Holes predrilled to 80 percent of Holes not predrilled nail diameter
End distance Edge distance Between nails Along grain Across grain
9.1.4
20d Sd
lOd Sd
20d 1 Od
lOd 3d
Nail length and timber thickness
For the basic loads to apply, the nails ~Iiouldfully penetrate the tabulated standard thickness of members or, for members receiving the nail point, should penetrate to an equivalent depth. Where the thickness of members is less than those tabulated, the basic load should be reduced proportionately. No increase in basic load is allowed for thickness of members greater than that in Table 2. The nail should be considered as non-load bearing if the penetration of the head side or point side is less than 5d. 9.1.5
Improved nails
For sc~uaregrooved or square twisted nails of steel with a yield stress of not less than 375 N/mm the basic loads given in Table 2 should be multiplied by 1.2. The nominal diameter of the nail should be assumed to be 0.75 times the distance between diagonally opposite corners of the cross-section. ,
9.1.6
Slant driving
The direction of the slant should be such that the joint will not loosen under load. 9.1.7
Avoidance of splitting
The basic loads for nails have been derived on the assumption that splitting of the timber does not occur to any significant extent. In wet timber which shows a marked tendency to split, (see Clause 6), the use of predrilied holes of diameter 80 percent of the nail diameter is recommended.
10
MS 544: PART5:2001
9.2
Withdrawal loads
9.2.1
Basic working loads
The basic working loads in withdrawal for plain shank, low carbon steel nails as specified in AS 2334 driven by hand, into side grain of timber are given in Table 7. Table 7. Basic withdrawal loads for one nail inserted at right angles to side grain
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
Diameter of nail
Basic withdrawal load (N/mm of penetration) for timber in group
(mm) 2.0 2.3 2.6 3.0 3.3 3.7 4.1
SWG 14 13 12 11 10 9 8
Ji 5.8 6.7 7.6 8.7 9.6 10.7 11.9
J2 4.1 4.7 5.3 6.1 6.7 7.5 8.3
J3 2.9 3.3 3.7 4.3 4.7 5.3 5.9
J4 2.0 2.3 2.6 3.0 3.4 3.8 4.2
J5 1.4 1.6 1.8 2.1 2.3 2.6 2.8
4.5
7
4.9 5.4 6.9 6.4
6 5 3 3
13.1
9.1
6.5
4.6
3.1
14.2 15.7 17.1 18. 6
9.9 10.9 11.9 13.0
7.0 7.7 8.5 9.2
5.0 5.5 6.0 6.5
3.4 3.7 4.1 4.4
NOTES:
1. No withdrawal load should be carried by a nail driven into the end grain of timbers. 2. The penetration ofthe nail should not be less than 15 mm.
9.2.2
Permissible loads
The permissible load F adm of a single nail in withdrawal from side grain shall be taken to be given by Fadm
=
k1k2 F
where; k1
=
k2
=
F
1.0 for all duration of loading;
=
1.0 for both wet and dry timber which subsequently will not change appreciably in moisture content. 0.25 where cyclic changes in moisture content can occur after nailing; and
=
the basic working load in withdrawal given in Table 7.
11
MS 544: PART 5 : 2001
9.2.3
Changes in moisture content
The values of basic resistance to withdrawal given in Table 7 apply to round wire nails driven into timber which subsequently will riot change appreciably in moisture content. Where large changes in moisture content of the timber subsequently to nailing are expected, the values given in Table 7 should be multiplied by 0.25.
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
9.2.4
Improved nails
The values of basic resistance to withdrawal given in Table 7 should be multiplied by 1 .5 for ringed-shank or annularly-threaded nails. No reduction in basic resistance to withdrawal of these nails need be made where timber seasons subsequent to nailing. However, no load in withdrawal should be carried by ringed-shank or annularly-threaded nails driven into the end grain of the timber.
10.
Screwed joints
10.1
Lateral loads
10.1.1 Basic working loads The basic working loads for plain steel wood screws as specified in AS 1476, whether driven by hand or by machine, in single shear in dry timber are given in Table 8. NOTE. In the absence of specific data, these loads may also be used for other forms of steel screws intended for the fabrication of timber joints. Loads for other diameters may be derived by linear interpolation in direct proportion to diameter raised to the power of 1.7.
Table 8. Dry basic single shear lateral loads for one wood screw inserted at right angles to side grain Diameter of screw
Standard thickness of members (mm) Head-side Point-side
(mm)
Gauge
2.7 3.1 3.4 3.8 4.2 4.5
4 5 6 7 8 9
10 11 12 13 15 16
4.9
10
5.2
Basic lateral load (N) for timber in group: Ji
J2
J3
J4
J5
19 22 24 27 29 32
498 587 655 748 843 915
410 484 540 617
340 401 448 511
282 333 371 424
229 270 302 344
695
576
477
388
755
625
518
421
17
34
1012
835
692
574
466
11
18
37
5.6
12
20
39
6.3 7.0
14 16
22 25
44 49
1087 1187 1366 1548
897 976 1126 1276
742 811 933 1057
616 672 774 877
500 546 628
7.7
18
27
54
1734
1430
1184
982
10.1.2 Permissible loads The permissible load
Fadm
for a laterally loaded screw shall be taken to be given by: Fadm
=
k1 k2 k13 k16 k17 F 12
712 798
MS 544: PART5:2001
where; the factor for duration of load given in Table 4;
=
k2
1.0 for dry timber 0.7 for wet timber;
=
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
=
k13
=
k16
=
F
1.0 for screws in side grain 0.7 for screws in end grain;
=
=
1.25 where the load is applied through metal side plates of adequate strength to transfer the load and the screws are a close fit to the holes in these plates 1.0 otherwise;
=
factor for multiple screw joints given in Tables 5.1 and 5.2; and
=
basic working load given in Table 8.
10.1.3 Spacings, edge and end distances Table 9 provides recommended minimum spacings, edge and end distances for screws stated in terms of the shank diameter d. Table 9. Minimum spacing, edge and end distances for screws Spacing type
Minimum distance
End distance
lOd
Edge distance
5d
Between screws -along grain -across grain
lOd 3d
NOTE. d = shank diameter of screws.
For spacing at an angle to the grain, interpolation according to Hankinson’s formula may be used. 10.1.4 Screw length and timber thickness For the basic loads to apply, the screws should fully penetrate the tabulated standard thickness of members, or for members receiving the screw point should penetrate to an equivalent depth. Where the thickness of members are less than those tabulated the basic load should be reduced proportionately. No increase in basic load is allowed for thickness of members greater than those in Table 8. The penetration of the point should be not less than 0.6 of the standard point side member.
13
MS 544: PART 5 : 2001
10.1.5 Pre-drilling The values given in Table 8 apply when the correct size lead holes have been drilled. The diameter of the hole for the shank must be equal to the diameter of the shank, and the lead hole for the threaded portion of the screw must not be greater than 7/8 of the root diameter of the screw adjacent to the shank. Screws installed directly without pre-drilling have the same value given in Table 8, provided that the timber does not split. 10.2
Withdrawal loads
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
10.2.1 Basic working loads The basic working loads for plain wood screws as specified in AS 1476 driven by hand or by machine from the side grain of dry timber are given in Table 10. The maximum working load that may be applied to any one screw shall not exceed the value appropriate to the diameter and metal from which the screw is manufactured as given in Table 11. Loads for other diameters may be obtained by linear interpolation in all tables. The basic working loads for wood screws driven into end grain shall not exceed 70 % of the values given in Table 10. Table 10. Dry basic withdrawal loads for one wood screw inserted at right angles to side grain Diameter of screw
Basic withdrawal loads (N/mm of penetration for timber) in group
(mm)
Gauge
Ji
J2
J3
J4
J5
2.7
4
26.5
19.2
14.1
10.3
7.3
3.1
5
30.2
21.9
16.1
11.8
8.4
3.4 3.8 4.2
6 7 8
33.0 36.8 40.5
24.0 26.7 29.4
17.6 19.6 21.5
12.9 14.3 15.8
9.1 10.2 11.2
4.5
9
43.2
31.4
23.0
16.9
12.0
4.9 5.2 5.6 6.3 7.0 7.7
10 11 12 14 16 18
46.9 49.7 53.3 59.7 66.1 72.4
34.0 36.0 38.7 43.3 47.9 52.5
25.0 26.4 28.4 31.8 35.2 38.5
18.3 19.4 20.8 23.3 25.8 28.2
13.0 13.8 14.8 16.5 18.3 20.0
Table 11. Maximum permissible withdrawal load per screw Maximum permissible withdrawal load, N Metal Screw size number 4 Steel and 18/8 stainless steel Brass and silicon bronze Aluminium alloy
2.74 730 560 430
I
10 I 12 Shank diameter (mm) 4.17 4.88 5.59 1650 2270 2960 1270 1750 2280 970 1340 1740
6
8
3.45 1110 850 650
14
I
14 6.30 3780 2910 2230
I
18 7.72 5600 4310 3300
MS544: PART5:2001
10.2.2 Permissible loads The permissible load
Fadm
for a screw in withdrawal shall be taken to be given by the lesser of
the value given in Table 11 and the value: Fadm =
k1 k2k13F
where, k1 k2
=
=
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
=
k13 F
1.0 for all duration of loading; 1.Ofordrytimber 0.7 for wet timber;
=
1.0 for screws in side grain 0.7 for screws in end grain; and
=
basic working load given in Table 10.
=
NOTE. The penetration of the screw point should not be less than 15 mm.
11.
Bolted joints
11.1
General
The basic working loads given in 11.2.1 and 11.2.2 are applicable to steel bolts as specified in AS 1111, when fitted into pre-drilled holes of diameter approximately 10 % greater than the bolt diameter and when fitted with washers as given in 11.2.5. 11.2
Lateral Loads
11.2.1 Basic working load parallel and perpendicular to grain The dry basic working load F for a single bolt bearing parallel and perpendicular to the grain and acting in single shear is given for a selection of bolt diameter and effective timber thickness in Table 12.
15
MS 544: PART 5 : 2001
Table 12. Dry basic loads for one bolt in single shear Effective* •timber thickness b (mm) 12.7
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
19.0
25.4
38.1
50.8
76.2
101.6
127.0
Bolt diameter
Basic load (kN) for timber in group J2 J3 J4
,~
J5
-_____
(mm) 6.3
Par 0.80
Perp 0.53
Par 0.63
Perp 0.37
Par 0.50
Perp 0.28
Par 0.41
Perp 0.20
Par 0.29
Perp 0.13
9.5
1.21
0.65
0.96
0.45
0.76
0.33
0.60
0.24
0.42
0.15
12.7
1.58
0.76
1.26
0.53
0.98
0.38
0.79
0.28
0.55
0.18
15.9 19.0 22.2
1.92 2.22 2.46
0.85 0.95 1.04
1.52 1.76 1.97
0.60 0.67 0.73
1.19 1.38 1.55
0.44 0.49 0.54
0.96 1.10 1.24
0.31 0.36 0.38
0.66 0.76 0.85
0.20 0.23 0.25
6.3
1.12
0.79
0.90
0.56
0.71
0.41
0.58
0.30
0.41
0.19
9.5 12.7 15.9 19.0 22.2 25.4
1.74 2.33 2.82 3.30 3.71 4.10
0.97 1.13 1.27 1.42 1.56 1.69
1.39 1.86 2.24 2.63 2.95 3.25
0.68 0.80 0.90 1.01 1.10 1.20
1.09 1.46 1.76 2.06 2.30 2.54
0.50 0.59 0.66 0.73 0.80 0.88
0.89 1.18 1.42 1.66 1.85 2.04
0.36 0.42 0.48 0.53 0.59 0.64
0.61 0.80 0.97 1.14 1.27 1.40
0.24 0.28 0.31 0.35 0.37 0.41
6.3
1.30
1.02
1.09
0.74
0.88
0.54
0.72
0.40
0.52
0.24
9.5 12.7
2.22 3.01
1.30 1.51
1.79 2.41
0.92 1.07
1.42 1.91
0.67 0.78
1.13 1.54
0.48 0.56
0.80 1.07
0.31 0.36
15.9
3.72
1.70
2.96
1.20
2.34
0.88
1.87
0.64
1.30
0.41
19.0 22.2
4.36 4.91
1.90 2.08
3.48 3.91
1.34 1.48
2.72 3.06
0.98 1.08
2.18 2.46
0.71 0.78
1.51 1.69
0.46 0.50
25.4 6.3
5.46 1.30
2.26 1.34
4.34 1.14
1.60 1.03
3.40 0.95
1.16 0.76
2.72 0.76
0.84 0.56
1.88 0.55
0.54 0.36
9.5 12.7 15.9 19.0 22.2 25.4
2.84 4.22 5.28 6.29 7.16 8.32
1.87 2.24 2.54 2.84 3.12 3.40
2.38 3.41 4.25 5.04 5.72 6.62
1.37 1.60 1.80 2.02 2.21 2.40
1.92 2.70 3.36 3.96 4.51 5.21
1.00 1.16 1.32 1.46 1.62 1.75
1.58 2.20 2.71 3.20 3.63 4.19
0.72 0.84 0.95 1.07 1.16 1.27
1.12 1.54 1.88 2.22 2.50 2.89
6.3
1.30
1.34
1.14
1.10
0.95
0.86
0.76
0.66
0.55
9.5 12.7 15.9
2.84 4.94 6.65
2.34 2.92 3.37
19.0
8.00
3.79
22.2 25.4 9.5 12.7 15.9 19.0 22.2
9.18 10.37 2.84 4.94 7.43 10.30 12.58
4.16 4.52 2.56 3.84 4.75 50 6.18
2.50 4.10 5.38 6.44 7.37 8.30 2.50 4.33 6.53 8.57 10.22
1.76 2.11 2.40 2.69 2.95 3.20 1.81 2.98 3.50 3.98 4.40
2.08 3.06 4.28 5.10 5.83 6.55 2.08 3.60 5.41 6.91 8.17
1.28 1.55 1.75 1.96 2.15 2.34 1.58 2.17 2.56 2.92 3.23
1.76 2.74 3.48 4.14 4.72 528 1.76 3.06 4.61 5.71 6.67
0.95 1.13 1.27 1.42 1.56 1.69 1.22 1.61 1.90 2.11 2.34
1.27 1.93 2.44 2.88 3.28 3.66 1.27 2.22 3.17 4.04 4.68
0.47 0.54 0.61 0.68 0.76 0.82 0.44 0.60 0.72 0.82 0.91 1.10 1.09 0.82 1.03 1.20 1.37 1.51
25.4
14.52
6.74
11.71
4.80
9.31
3.50
7.56
2.53
5.27
1.63
28.6 12.7 15.9 19.0 22.2 25.4 28.6 31.7
15.94 4.94 7.43 10.30 13.43 16.99 19.62 21.74
7.33 3.98 5.62 6.85 7.86 8.74 9.61 10.41
12.85 4.33 6.53 9.02 11.80 14.11 15.96 17.59
5.20 3.16 4.37 5.15 5.77 6.34 6.89 7.46
10.16 3.60 5.41 7.49 9.79 11.40 12.80 14.02
3.79 2.47 3.20 3.76 4.22 4.63 5.05 5.45
8.23 3.06 4.61 6.38 8.14 9.42 10.48 11.44
2.74 1.90 2.38 2.76 3.08 3.37 3.66 3.94
5.75 2.22 3.17 4.39 5.76 6.66 7.36 7.99
1.76 1.26 1.55 1.76 1.98 2.17 2.36 2.54
15.9
7.43
5.62
6.53
4.45
5.41
3.48
4.61
2.68
3.17
1.78
19.0 22.2 25.4 28.6
10.30 13.43 16.99 20.53
7.49 9.12 10.42 11.53
9.02 11.80 14.92 18.02
5.94 6.92 7.73 8.48
7.49 9.79 12.38 14.72
4.39 5.08 5.65 6.20
6.38 8.34 10.55 12.20
3.28 3.73 4.15 4.52
4.39 6.02 7.62 8.65
2.14 2.40 2.66 2.92
31.7
24.31
12.72
20.22
9.23
16.33
6.74
13.50
4.90
9.55
3.17
16
MS544: PART5:2001
Table 12. Dry basic loads for one bolt in single shear (continued) Effective timber thickness*
Bolt diameter
(mm) 152.4
(mm) 19.0
Par 10.30
Perp 7.49
Par 9.02
Perp 5.94
Par 7.49
Perp 4.64
Par 6.38
Perp 3.56
Par 4.39
Perp 2.36
22.2
13.43
9.61
11.80
7.63
9.79
5.72
8.34
4.27
6.02
2.78
25.4
16.99
11.94
14.92
8.93
12.38
6.52
10.55
4.82
7.62
3.11
28.6
20.53
13.26
18.02
9.91
14.98
7.26
12.74
5.34
9.20
3.42
31.7 22.2
24.31 13.43
14.74 9.61
21.34 11.80
10.85 7.63
17.72 9.79
7.94 5.95
15.08 8.34
5.83 4.57
10.75 6.02
3.73 3.05
25.4 28.6 31.7
16.99 20.53 24.31
11.94 14.52 17.36
14.92 18.02 21.34
9.48 11.53 13.56
12.38 14.98 17.72
7.40 8.82 9.92
10.55 12.74 15.08
5.69 6.62 7.36
7.62 9.20 10.90
3.78 7.32 4.79
Ji
203.2
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
Basic load (kN) for timber in group J2
the loads for intermediate thickness may be obtained by linear interpolation. The units for timber thickness and bolt diameter are direct conversion from imperial units. *
11.2.2 Basic working load for a bolted joint system a)
Parallel and perpendicular to grain For a bolt in other than a two-member joint, the basic working load shall be multiples of F11 for parallel loading as shown in Table 13 and F1 for perpendicular loading as shown in Table 14 for the appropriate type of joint.
b)
Other angles to grain For systems loaded at an angle a to the grain, the basic working load is given by use of Hankinson’s formula as follows:FF II
Fsin2ci+F cos2a 1
1
Hankinson’s formula is conveniently evaluated by means of the nomogram given in Figure 3.
17
MS 544: PART 5 : 2001
Table 13. Basic working loads for a bolted joint system loaded parallel to grain Type of joint
Effective timber thickness b
Basic load F
Smaller of 2b and 2b 1 2
F
Smaller of 2b and b 1 2
2 F
1. Two member
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
I
2. Three member
3.
11
I
Multiple member
A
I
11
1I~I~1
I
II
11
b
B C ID
j /
i)
Between A and B
ii)
Smaller of b and b 1 C —2 Between B and
iii)
Smaller of b and b 2 3 etc.
1 b 2 b 3 b4
—
i)
F
ii)
F
iii)
11
11 etc.
=
Total basic load sum of basic loads (i), (ii), etc.
18
MS 544: PART5 :2001
Table 14. Basic working loads for a bolted joint system loaded perpendicular to grain Type of joint 1. Two member
Effective timber thickness b
Basic load F ~
2b, but not exceeding twice thickness of side member.
F ~
b,
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
ft~
2. Three member b 2
~
4.
i)
b but not exceeding twice 2 thickness of thinner side member.
i)
2F
ii)
2 b, but not exceeding thickness of inner member.
ii)
2 F
1)
1)
F
ii)
F
iii)
Between A and B — thinner of b, and b Between B and C —2 thinner of b and b Between C 2and D —3
iv)
thinner of b and b 3 4 etc.
b
1
Multiple member
ii)
ii)
1
1
1
1 F 1
Total basic load etc. = sum of basic iv) loads (i), (ii), (iii) etc.
~
~
19
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
MS 544: PART5 :2001
F;
Fi Figure 3. Graph of Hankinson formula EXAMPLE Given F
11
=
9.0 kN, F
To find Fcc connect F
1
11
= =
6.0 kN, cx 9.0 to F
1
=
=
60
6.0.
At intersection with 60 line, construct line parallel to grid line to axis at Fcc
=
6.5.
11.2.3 Permissible loads The permissible load F
adm
of a laterally loaded bolt system shall be taken to be given by: 20
MS 544: PART 5 : 2001
11.2.3 Permissible loads The permissible load F F adm
=
adm
of a laterally loaded bolt system shall be taken to be given by:
k1 k2 k16 k17 F
where, k1
=
=
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
=
k16
=
the factor for duration of load given in Table 4; 1.Ofordrytimber 0.7 for wet timber; 1 .25 for bolts that transfer load through metal side plates of adequate strength and the bolts are a close fit to the holes in these plates provided that b/d > 5 for loads acting parallel to grain and b/d > 10 for loads acting perpendicular to the grain (where b denotes the effective timber thickness and d is the bolt diameter)
=
1.0 otherwise;
k17
=
factor for multiple bolted joint given in Table 15; and
F
=
basic working load as derived in 11.2.2.
Table 15. Values of factor k17 for use in the design of multiple connector joints of bolts, coach screws, split ring and shear plates joint
Value of k
~[
17
fla4
restraint*) restraint*)
fla
5
fib
=10
tjo
=15
17o
16
1.00 1.00
0.95 0.95
0.80 0.80
0.65 0.55
0.62 0.50
0.50
0.50
0.50
0.50
0.50
of fasteners in each row per interface. restraint’ refers to the possibility of restraint to timber shrinkage due to the joint detail.
21
MS 544: PART 5 : 2001
11.2.4 Spacings, edge and end distances Spacings, edge and end distances shall comply with the following requirements: a)
Loads parallel to grain The basic working loads given in Tables 12 and 13 apply to joints in which the edge, end and between- fastener spacings are not less than those shown in Figure 4a. The distance a indicated in the figure shall be at least (n 2)d with a minimum of 2.5d, where n is the total number of bolts in the joint and d is the diameter of the bolt.
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
—
Similarly, the required end distance ‘par shall be at least 7d in tension joints in both wet and dry timber and 4d in compression joints and in joints subjected to bending moment for both moisture conditions. However, lesser end distances may be used in tension joint provided that the basic load is reduced in proportion to the reduction in end distance. Nevertheless, in no case shall the end distance for tension joints be less than 6d for wet timber and 4dfor dry timber. b)
Loads perpendicular to grain The minimum edge, end and between-fastener spacing shall not be less than those shown in Figure 4b. The distance a shall be at least 2.5d for a bid ratio of 2, and it shall be increased proportionately so that it is at least 5d for a bid ratio of 6 or more, where b is the thickness of the member loaded perpendicular to the grain.
c)
Loads acting at an angle to the grain For loads acting at an angle 00 to 30° to the grain, the spacings, edge and end distances may be taken as for loads parallel to the grain. For loads acting at an angle of 30° to 90° to the grain, the spacings, edge and end distances may be taken as for loads acting perpendicular to the grain.
22
MS 544: PART 5 : 2001
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
(a) Load applied parallel to grain
4
par
(b) Load applied perpendicular to grain Figure 4. Spacing, edge and end distances for bolted joints
23
MS 544 : PART 5 : 2001
11.2.5 Washers In all timber-to-timber bolted structural joints, every bolt shall be provided with a washer at each end, of a size not less than that stated in Table 16. If smaller washers are used, then the basic working load given in 11.2 shall be reduced in proportion to the dimension of the washer diameter or side length. Table 16. Minimum required size of washers for structural bolted joints Washer size (mm)
diameter
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
.
11.3
.
.
Thickness
Mm. diameter for round washers
Mm. side length for square washers
1.6
30
25
2.0 2.5
36 45
32 40
3.0
55
50
4.0 5.0 6.0
65 75 85
57 65 75
Axial loads
Where bolts are loaded axially, the basic working load of the bolt shall be taken as the lesser of the axial strength of the bolt and the bearing strength of the timber under the washer when loaded perpendicular to the grain. The design axial strength of bolts and the effective diameter for use in computing the bearing pressure on the timber are given in Table 17. Table 17. Design parameters for bolts under axial load Bolt diameter (mm)
Axial strength of bolt (kN)
Effective diameter of a standard washer* in bearing (mm)
M6 M8
4.0 7.5
M10 M12 M16
11.5 17 32
16 21 27 31
M20 M24
50 72
50 60
M30
115
69
M36
165
78
—
31
* Standard washers are washers having the minimum dimensions shown in Table 16. The effective diameter is less than the actual diameter because it includes an allowance for bending ofthe washer.
24
MS544: PART5 :2001
12.
Coach screws
12.1
General
The basic working loads given in the following clauses are applicable to steel coach screws as specified in AS 1393 and as shown in Figure 5. 12.2
Lateral loads
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
For coach screws bearing laterally in dry timber, the provision of Clause 11 for bolts shall apply, subject to the following conditions: a)
for the purpose of Clause 11, a coach screw shall be considered to be a bolt of diameter equal to the shank diameter of the screw;
b)
the screws shall be fitted with washers as specified in 11.2.5;
c)
in a two-member joint, the thinner member shall have a minimum thickness of three times the shank diameter of the coach screw;
d)
The diameter of the hole for the shank shall not be less than the shank diameter of the screw nor exceed it by more than 1 mm or 10 percent of the shank diameter, whichever is the lesser. The diameter of the hole for the threaded portion of the screw shall not exceed the root diameter of the screw. The depth of the hole shall not be less than the intended depth to which the screw is to be driven. The screw shall not be hammered into place but turned with a hand operated or machine operated wrench; and
e)
Timber thickness and screw lengths as shown in the Figure 6 shall be such that: i) ii)
thickness of first member, t1 > 3d depth of penetration into second member for species in joint groups: JlandJ2 t~ >7d J3 t~ >8d J4andJ5 t~>lOd ,
For the lesser values of t~the basic load shall be reduced in proportion to the decrease in t~ and the coach screw shall be considered as non-load bearing if t~ is less than 4d.
25
MS 544: PART5:2001
Head
~~:~—;i~ ID
.
D = Shank or nominal diameter
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
S
=
Length of shank or unthreaded portion
T = Length of threaded portion
Figure 5. Coach screw
Figure 6. Timber thicknesses and fastener lengths for coach screws
26
MS 544: PART 5 : 2001
12.3
Withdrawal loads
12.3.1 Basic working loads The basic working loads for coach screw in withdrawal from the side grain are given in Table 18. 12.3.2 Permissible loads The permissible withdrawal load given by:
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
Fadm
=
Fadm
for a coach screw in withdrawal shall be taken to be
k1 k2k13F
but not greater than the value given in Table 19 where; k1
=
k2
= =
k13
1.Ofordrytimber 0.7 for wet timber;
=
1.0 for coach screws in side grain 0.7 for coach screws in end grain; and
=
basic working load for coach screws in side grain, given in Table 18.
=
F
1.0 for coach screw for all duration of loading;
Table 18. Dry basic withdrawal loads for coach screws in side grain Shank diameter (mm)
J1
J2
J3
J4
J5
6
57
41
30
22
16
8
75
54
40
29
21
10
93
68
50
26
12 16
111 146
36
80 106
59 78
43 57
31 40
20
181
131
96
71
50
Basic withdrawal load, N per mm penetration of tread for timber in group
Table 19. Maximum permissible withdrawal loads per coach screws Nominal diameter of coach screw (mm)
Maximum permissible withdrawal load N
6 8 10
2000 4000 6000
12
9000
16
20000
20
31500
27
MS 544: PART 5 : 2001
13.
Split-ring connectors
13.1
General
13.1.1 Connector sizes The recommendations contained in this clause are applicable to the sizes of split-ring connectors given in Table 20 and conforming to BS 1579. Table 20. Sizes of split-ring connectors and minimum sizes of washers
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
Nominal size of connectors
Minimum size of round or square washers
Nominal size and thread diameter of bolt
64
M12
Diameter or length of side (mm) 50
102
M20
75
(mm)
I
Thickness
J
(mm) 3
I
NOTE. The sizes given in this table are metric conversions of the imperial sizes given in BS 1579.
13.1.2 Bolts and washers The diameter of the bolts to be used with the connectors are given in Table 20. Round or square washers should be fitted between the timber and the head and nut of the bolt. The minimum size of washer to be used with each connector is given in Table 20. 13.1.3 Joint preparation To prepare a connectored joint, the positions of the bolt holes should be set out accurately with reference to the point of intersection of the centre-lines of the members. One of the following two procedures should be used when drilling the bolt holes: a)
fit the members together in their correct positions and clamp while drilling the bolt holes through all the members; and
b)
drill the bolt holes in the individual members using jigs or templates to locate the bolt holes accurately.
Bolt holes should be within 2 mm ol their specified position. The contact surfaces of the timber members should be grooved to the dimensions given in Table 21. The grooves for split-rings may be cut simultaneously with the drilling of the bolt holes if procedure b) is used.
28
MS 544: PART 5 : 2001
Table 21. Dimensions of circular grooves for split-ring connectors Split-ring size (mm) 64
Dimensions of groove (mm) 65.0
4.6
9.5
102
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
13.2
Effective cross section
The effective cross-section of each member at a joint should be determined by deducting the projected area from the gross area of the cross-section of the connector recess (i.e. 705 mm2 for each 64 mm split-ring, or 1455 mm2 for each 102 mm split-ring) and the projected area of the groove. The depths of the connector grooves are given in Table 21. When assessing the effective cross-section of multiple connector joints, all connectors and their bolts that lie within a distance of 0.75 connector diameters, measured parallel to the grain from a given cross-section should be considered as occurring at that cross-section. Then the effective cross section should be determined by deducting the given net projected areas of the connector grooves and bolt holes from the gross area of the cross-section being considered. 13.3
Basic loads
The basic working loads for parallel and perpendicular to the joint in dry timber are given in Table 22. These loads apply to a connector unit comprising one split-ring in the contact faces of a timber-to-timber joint with its bolt in single shear. When loaded at an angle a to the grain, the basic load is given by use of Hankinson’s formula or evaluated by means of the graph as given in Figure 3.
29
0
M12
M20
64
102
41 50
63 75
32
36
41
19.03 20.25
33.34 26.20
24.63
20.96
17.55
13.57 16.20
11.67
9.57
7.82
Par
10.08
31.34
26.67
22.34
15.48
29
12.69
40
50
8.27
Perp
6.77
Ji
10.37
25
32
22
Par
29
(mm)
Connectors on both sides and on same bolt
~mm)
Connectors on one side only
intermediate thickness may be obtained by linear interpolation.
(mm)
(mm)
1) Loads for
Bolt diameter
Split-ring diameter
Actual thickness of members~ J2
15.85
14.90
12.68
10.62
7.70
6.31
5.16
Perp
20.18
18.97
16.14
13.52
8.89
7.29
5.96
Par
J3
12.51
11.76
10.01
8.38
5.93
4.86
3.97
Perp
15.54
14.61
12.43
10.41
6.77
5.55
4.54
Par
Basic load~(kN) for timber in group
Table 22. Dry basic loads for one split-ring connector unit
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
J4
9.88
9.29
7.90
6.62
4.57
3.75
3.06
Perp
11.64
10.94
9.31
7.8
5.01
4.11
3.36
Par
J5
7.60
7.14
6.08
5.09
3.42
2.80
2.29
Perp
0 0
01
Ui
Cl)
MS544: PART5:2001
13.4
Permissible loads
The permissible load Fadm for split-ring connector shall be taken to be given by: k1
Fadm
1(2
k17 k18 F
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
where; k1
=
factor for duration of load given in Table 4;
k2
=
1.Ofordrytimber
=
0.7 for wet timber;
k17 k18
factor for multiple connector joints given in Table 15; 1.0 for standard and end distance, edge distance and connector spacing as given in Tables 23, 24 and 25 respectively modification factor for the relevant connector spacing (ks), end distance (kc) and edge distance (k0) which are less than the corresponding standard values as given in Tables 25, 26 and 27 respectively. (The lowest factor of the values of k5 kc and kD is to be used (see 13.5); and
=
=
F 13.5
=
basic load given in Table 22.
Spacing, edge and end distances
Associated with each size of split-ring connector is standard end distance, edge distance and spacing between connectors which permit the basic load to apply. These standard distance s are given in Table 23 to Table 25. If the end distance, edge distance or spacing is less than the standard, but more than the minimum, the basic load should be modified as given in 13.4. No increase in load is permitted if end distance, edge distance or centre spacing exceed the standard values. The definition of end distance, edge distance and spacing is illustrated in Figure 7. If split-ring connectors are used in wet timber, the standard end distance should be multiplied by 1 .5. One-half of this increased end distance should be taken as the minimum end distance, with a permissible load of one-half of that permitted for the standard end distance.
31
MS 544: PART 5 : 2001
Table 23. End distances for split-ring and shear-plate connectors Type of end distance
1~ distance (mm)
Angle 1) of load to grain cc
End
Connector size 102mm split-ring or 102mm 64 mm split-ring or 67mm shear-plate shear-plate
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
Unloaded
Loaded
(degrees)
Minimum
Standard
Minimum
Standard
0 45 90 Oto9O
64 67 70 70
102 121 140 140
83 86 89 89
140 159 178 178
For intermediate angles and end distances, values should be obtained by linear interpolation.
Table 24. Edge distances for split-ring and shear-plate connectors Type of edge distance
Unloaded Loaded
“
Angle 1) of load to grain cx
Edge” distance (mm) Connector size 64mm split-ring or67 mm 102mm split-ring or 102mm shear-plate shear-plate
(Degrees)
Minimum
Standard
Minimum
Standard
Oto9O 0 45 90 45to90
44 44 44 44 44
44 44 54 64 70
70 70 70 70 70
70 70 79 87 95
For intermediate angles and end distances, values should be obtained by linear interpolation.
32
MS 544: PART5 :2001
Table 25. Spacing modification factor, k9, for split-ring and shear-plate connectors Angle of load to grain a (degrees)
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
0
15
30
45
60 to 90
Angle ~ of connector axisto grain B (degrees)
Spacing (mm) k~=0.75 Minimum
ks =0.80
k~=0.95
k =1.00 5 Standard
0
64 mm split-ring or 6 7 mm shear-plate 89 105 121 140
156
171
15
89
102
117
130
146
157
30 45 60
89 89 89
98 92
108 95
114 105
124 108
132 112
75 90
89 89
92 89 89
92 89 89
95 92 89
95 92 89
98 91 89
0
89
102
114
127
140
152
15 30
89 89
102 98
111
124
133
145
45 60
89 89
95 92
105 98 95
114 105 98
124 108 102
129 114 103
75 90
89 89
92 89
92 92
95 92
95 95
97 95
0 15
89 89
105 105
114 111
124 121
130 127
30
89
98 95 95
45 60
89 89
92 92
102 95 95
108 105 98
114 108 102
119 111
75
89
92
92
95
95
99
90
89
92
92
95
95
98
0
89
~2
95
102
105
108
15
89
92
95
30 45 60
89 89 89
92 92 92
95 95 95
102 102 102
105 105 105
108 107 106
75 90
89 89
92 92
95 95
98 98 98
102 102 102
106 105 105
0
89
89
89
89
89
89
15 30 45
89 89
89
89
89
89
90
60 75
80 92 92 95
92 95 95 98
92 95 98 102
93
89 89 89
89 92 92 92
97 102 106
90
89
92
95
102
105
108
k~=0.85
33
ks =0.90
104
MS 544: PART 5 : 2001
Table 25. Spacing modification factor, k5, for split-ring and shear-plate connectors (continued)
Angle of load to grain cc (degrees)
Angle” of connector axisto grain 0 (degrees)
k~=0.75 Minimum
Spacing (mm) i(~=0.85 k~=0.90
k~=0.80
k~=0.95
k =1.00 5 Standard
102 mm split-ring or 102mm shear-plate
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
0
15
30
45
60 to 90
0 15 30
127 127 127
146 143 140
168 162 149
187 178 162
210 197 171
229 213 183
45 60 75
127 127 127
133 130 127
140 133 127
146 133 130
149 142 130
157 140 130
90
127
127
127
127
127
127
0 15
127 127
143 140
159
171
187
203
30 45
127 127
137 1~3
152 146 140
168 159 149
181 168 156
195 178 161
60 75 90
127 127 127 127
130 130 130 137
133 133 130
140 133 133
142 137 137
147 140 137
127 127
137 133
146 146 143
159 156 149
168 165 159
178 175 168
45 60 75
127 127 127
133 133 130
140 137 137
90
127 127
130 133
137 137
146 143 140 140
152 146 145 143
160 152 148 146
143
146
152
133 133
137 137
45 60
127 127 127 127
133 133
137 140
143 143 143 146
146 146 146 149
152 153 154 155
75 90
127 127
133 133
140 140
146 146
149 149
156 156
0
127
127
127
427
127
127
127
129
0 15 30
0 15 30
15
~
127
127
127
127
30 45 60
127 127 127
127
130
130
133
134
130 133
133 137
133 143
137
142
75
127
133
140
90
127
133
143
146 149
146 152 159
152 161 165
34
MS 544: PART5:2001
Table 26. End distances modification factor, kc, for split-ring and shear-plate connectors Value of_k
0
Unloaded Connector size 64 mm split-ring or 67 mm shear-plate
102 mm split-ring or 102 mm shear-plate Angle
0
45
90
1>
0
of load to grain a 45
90
-
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
Loaded . Connector size 102 mm 64 mm splitring or 67 split-ring or mm shear102 mm plate shear-plate 0 to 90
0 to 90
.
0.63
-
-
-
-
-
-
-
0.68
0.64
0.62
-
-
-
0.62
-
0.73
0.68
0.65
-
-
-
0.65
-
0.78
0.71
0.67
-
-
-
0.67
-
0.83
0.75 0.78
0.70 0.73
0.63 0.67
-
-
0.70
-
0.88
0.64
0.62
0.73
0.62
0.93
0.82
0.76
0.70
0.67
0.65
0.76
0.65
0.98
0.85
0.78
0.73
0.69
0.67
0.78
0.67
1.00
0.89
0.81
0.77
0.72
0.69
0.81
0.69
1.00
0.92
0.84
0.80
0.74
0.71
0.84
0.71
1.00
0.96
0.86
0.83
0.77
0.73
0.86
0.73
1.00
0.99
0.89
0.87
0.80
0.75
1.00
0.92
0.90
0.82
0.75 0.77
0.89
1.00
0.92
0.77
1.00
1.00
0.95
0.93
0.80
0.95
0.80
1.00
1.00
0.97
0.97
0.85 0.88
0.82
0.82
1.00
1.00
1.00
1.00
1.00
1.00
1.00 1.00
0.90 0.93
0.84 0.86
0.97 1.00 1.00
0.86
1.00
1.00
1.00
1.00
0.95
0.88
1.00
0.88
1.00
1.00
1.00
1.00
0.98
0.90
1.00
0.90
1.00 1.00 1.00
1.00 1.00
1.00 1.00 1.00
1.00 1.00 1.00
0.92 0.94 0.97
1.00 1.00 1.00
0.92
1.00
1.00 1.00 1.00
1.00
1.00
1.00
1.00
1.00
0.99
1.00
0.99
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
intermediate angles and end distances, values should be obtained by linear interpolation.
35
0.84
0.94 0.97
MS 544: PART 5 : 2001
Table 27. Loaded, edge distances modification factor, k~,for split-ring and shear-plate connectors Edge Distance (mm)
Value of ,~D Connector size 64 mm split-ring or 67 mm shear-plate
102 mm split-ring or 102mm shear-plate
Angle ~ of load to grain a 0
15
30
45
0
15
30
45 to 90
50
1.00 1.00
0.94
0.89
0.98
0.93
0.83
-
-
-
-
0.87
-
-
-
55
1.00
1.00
-
0.96
0.90
60
1.00
-
-
1.00
0.99
0.93
.
65
1.00
1.00
1.00
0.97
-
-
-
-
70
1.00
1.00
1.00
1.00
1.00
0.94
0.89
0.83
75 80
1.00 1.00
1.00 1.00
1.00 1.00
1.00 1.00
1.00
0.98
0.92
0.86
1.00
1.00
0.95
0.90
85
1.00
1.00
1.00
1.00
1.00
1.00
0.99
0.93
90
1.00
1.00
1.00
1.00
1.00
1.00
1.00
0.97
95
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
45
“
-
-
-
For intermediate angles and end distances, values should be obtained by linear interpolation.
a4
a1
a3 F-
Legend: a, a 2 a a3
4
= = = =
Spacing parallel to grain; Spacing perpendicular to grain; end distance; and
edge distance.
Figure 7. Spacing, Edge and End distances for split-ring and shear-plate connectors
36
MS544: PART5 :2001
14.
Shear plate connectors
14.1
General
14.li Connector sizes The recommendations contained in this clause are applicable to the sizes of shear-plate connectors given in Table 28 and conforming to BS 1579. The following requirements relate to shear plate connectors of nominal 67 mm and 102 mm sizes.
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
Table 28. Sizes of shear-plate connectors and minimum sizes of washers Nominal size of connector
Nominal size and thread diameter of bolt
Minimum size of round or square washers
(mm)
Diameter or length of side (mm)
Thickness (mm)
67
M20
75
5
102
M20
75
5
NOTE. The sizes given in this table are metric conversions of the imperial sizes given in BS 1579.
14.1.2 Bolts and washers The diameter of the bolts to be used with the connectors are given in Table 20. Round or square washers should be fitted between the timber and the head and nut of the bolt. The minimum size of washer to be used with each connector is given in Table 20.
14.1.3 Joint preparation To prepare a connectored joint, the positions of the bolt holes should be set out accurately with reference to the point of intersection of the centre-lines of the members. One of the following two procedures should be used when drilling the bolt holes: a)
fit the members together in their correct positions and clamp while drilling the bolt holes through all the members; and
b)
drill the bolt holes in the individual members using jigs or templates to locate the bolt holes accurately.
Bolt holes should be within 2 mm of their specified position. The contact surfaces be within 2 mm of the timber members should be recessed to the dimensions shown in Figure 8. The recesses for shear-plates may be cut simultaneously with the drilling of the bolt holes if procedure b) is used. 37
MS 544: PART 5 : 2001
067 L
057
J
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
11.5
Figure 8. a) Recess for 67 mm connector unit 0102.5 089 039.5
16.5
13
6.0
022~ ~
.4
Figure 8. b) Recess for 102 mm connector unit All dimensions are in millimetres.
Figure 8. Dimension of circular recesses for shear-plate connector units conforming to
BS 1579
38
MS 544: PART 5 : 2001
14.2
Effective cross section
The effective cross-section of each member at a joint should be determined by deducting the projected area from the gross area of the cross-section of the connector recess (i.e. 770 mm2 for each 67 mm shear-plate, or 1690 mm2 for each 102 mm shear-plate) and the projected area of the bolt hole not within the projected area of the recess. The depths of the connector recess are 11.5 mm and 16.5 mm for the 67 mm and 102 mm shear-plates, respectively.
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
When assessing the effective cross-section of multiple connector joints, all connectors and their bolts that lie within a distance of 0.75 connector diameters, measured parallel to the grain from a given cross-section should be considered as occurring at that cross-section. Then the effective cross section should be determined by deducting the given net projected areas of the connector recesses and bolt holes from the gross area of the cross-section being considered. 14.3
Basic loads
The basic working loads for parallel and perpendicular to the grain in dry timber are given in Table 29. These basic loads apply to a connector unit either: a)
one shear plate with its bolt in single shear in a steel plate-to timber joint; or
b)
two shear plate back to back with the bolt in single shear, in a timber-to timber joint.
When loaded at an angle a to the grain, the basic load is given by use of Hankinson’s formula or evaluated by means of the graph as given in Figure 3.
39
0
M20
67
10.08
15.48*~
15.63 16.81
25.73”~ 27.67~
75 92
41
44
14.62
24.07~
67
-
12.48
20.48
50
-
41
67
9.48
14.55~
50
-
7.76
11.92
41
Perp
-
(mm) Par
JI
Connectors on both sides and on same bolt (mm)
Connectors on one side only
‘~
“Loads for intermediate thickness may be obtained by linear interpolation. a) see clause 14.4
M20
(mm)
(mm)
102
Bolt diameter
Shearplate diameter
Actual thickness of members
22.05
20.51
19.18
16.32
11.67
10.97
8.99
~ar
J2
13.16
12.24
11.45
9.74
7.70
7.24
5.93
Perp
17.57
16.34
15.29
13.00
8.89
8.36
6.83
Par
J3
10.38
9.65
9.03
7.68
5.93
5.57
4.57
Perp
14.00
13.02
12.18
10.36
6.77
6.36
5.21
Par
Basic load~(kN) for timber in group
Table 29. Dry basic loads for one shear plate connector unit
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
~J4
8.20
7.63
7.13
6.07
4.57
4.30
3.52
Perp
10.88
10.12
9.47
8.05
5.01
4.71
3.86
Par
J5
6.31
5.87
5.49
4.67
3.42
3.21
2.63
Perp
0 0
—I 01
-o
(‘1
CI)
MS 544: PART5:2001
14.4
Permissible loads
The permissible loadFadm for a shear plate connector shall be the lesser of by: a)
Fadm
=
The limiting values given in Table 30
or b)
Fadm =
k1 k2k17k18F
where k1 k2 k17 and k18 are as defined in 13.4 and F is the basic load given in Table 29.
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
NOTE. Loads mark with a cross (x) in Table 29 exceed the limiting values given in Table 30 but are included for interpolation purposes.
Table 30. Limiting values for permissible loads on one shear-plate connector unit Shear-plate diameter
Nominal bolt size
All loading except shortand very short-term loading
All loading including short- and very shortterm loading
(mm)
(mm)
(kN)
(kN)
67
M20
12.9
17.2
102
M20
22.1
29.5
14.5
Spacing, edge and end distances
As defined in 13.5 where the given data for split-ring connectors are applicable to shear plate connectors.
41
Licenced to UNIVERSITI MALAYSIA PAHANG (UMP) / Downloaded on : 01-Jul-2009 / Single user licence only, copying and networking prohib
Printed by: SSP, SIFIIM Berhâd
