1 presented by the wood truss council of america
TRANSCRIPT
1
Presented by thePresented by the
Wood Truss Council of America Wood Truss Council of America
Permanent BracingPermanent Bracing
of Metal Plate Connected of Metal Plate Connected
Wood TrussesWood Trusses
3
Overview of the Truss IndustryOverview of the Truss Industry
Metal connector plate invented 1952
4
Overview of the Truss IndustryOverview of the Truss Industry
Metal connector plate invented 1952
5
Overview of the Truss IndustryOverview of the Truss Industry
Industry evolved
6
Overview of the Truss IndustryOverview of the Truss Industry
Now $8 billion industry in the US World wide market
7
Overview of the Truss IndustryOverview of the Truss Industry
Components for roofs, floors and walls
8
ResidentialResidential
9
ResidentialResidential
10
Multi-FamilyMulti-Family
USDA Forest Products LabUSDA Forest Products Lab
11
WoodWood
American Forest & Paper AssociationAmerican Forest & Paper Association
90% of residential framing
12
3.9 Wood Trusses3.9 Wood Trusses Heavy timber truss
bolt or split ring connected Plywood gusset truss
Post WW-II construction Metal truss plate invented in 50’s Today major EWP component
Residential 62%, Multifamily 64% roof market share
Residential 15%, Multifamily 26% floor market share
13
3.9 Wood Truss Standards3.9 Wood Truss StandardsNational Design Standard for Metal
Plate Connected Wood Truss Construction ANSI/TPI 1 – 1995
National Standard and Recommended Guidelines on Responsibilities for Construction Using Metal Plate Connected Wood Trusses ANSI/TPI/WTCA 4 - 2002
14
3.9 Metal Connector Plates3.9 Metal Connector Plates
15
3.9 Connector Plate Testing3.9 Connector Plate Testing
Develop proprietary plate values
16
3.9 Full Scale Truss Testing3.9 Full Scale Truss TestingVerification of Design Methodology
17
3.9 Truss Design Process3.9 Truss Design Process
18
3.9 Truss Layout Program3.9 Truss Layout Program
19
3.9 Truss Layout Program3.9 Truss Layout Program
20
3.9 Truss Layout Program3.9 Truss Layout Program
21
3.9 Truss Placement Plans3.9 Truss Placement Plans
22
3.9 Truss Analysis Program3.9 Truss Analysis Program
23
3.9 Truss Applications3.9 Truss Applications
24
3.9 Truss Floors3.9 Truss Floors
25
3.9 Truss Floors3.9 Truss Floors
3.9 Truss Roofs3.9 Truss Roofs
3.9 Truss Roofs3.9 Truss Roofs
3.9 Truss Roofs3.9 Truss Roofs
29
3.9 Truss Roofs3.9 Truss Roofs
3.9 Truss Roofs3.9 Truss Roofs
31
3.9 Truss Job Site Package3.9 Truss Job Site PackageTruss design drawings
32
3.9 Truss Job Site Package3.9 Truss Job Site PackageTruss placement plan
33
3.9 Truss Job Site Package3.9 Truss Job Site PackageHandling, Installing & Bracing Guidelines
34
3.9 Truss Job Site Package3.9 Truss Job Site PackageHandling, Installing & Bracing Guidelines
35
3.9 Truss Job Site Package3.9 Truss Job Site PackageHandling, Installing & Bracing Guidelines
36
3.9 Truss Job Site Package3.9 Truss Job Site PackageHanger details
37
3.9 Truss Long Term Storage3.9 Truss Long Term Storage Blocking to keep trusses off the ground
38
3.9 Truss Storage Conditions3.9 Truss Storage Conditions
39
< 6 inches
3.9 Truss Handling3.9 Truss Handling
40
3.9 Truss Handling3.9 Truss HandlingShort Span < 30 ft
41
3.9 Truss Handling3.9 Truss HandlingShort Span
42
3.9 Truss Handling3.9 Truss HandlingHandling Medium Span < 60 ft
43
3.9 Truss Handling3.9 Truss HandlingMedium Span
44
3.9 Truss Handling3.9 Truss HandlingHandling Long Span > 60 ft
45
3.9 Truss Handling3.9 Truss HandlingLong Span
46
3.9 Truss Ground Bracing3.9 Truss Ground BracingSubstantial bracing for first truss
47
3.9 Truss Bracing3.9 Truss BracingLateral and Diagonal
48
3.9 Truss Bracing3.9 Truss BracingShort Pieces & Diagonal Bracing
49
3.9 Truss Bracing3.9 Truss BracingSheathe Early & Often
50
3.9 Truss Bracing3.9 Truss BracingPre-Assemble & Lift-in-place
51
3.9 Truss Bracing3.9 Truss BracingResults of Bad Bracing
52
3.9 Truss Bracing3.9 Truss BracingResults of Bad Bracing
53
3.9 Truss Bracing3.9 Truss BracingResults of Bad Bracing
54
3.9 Truss Bracing3.9 Truss BracingResults of Bad Bracing
55
3.9 Truss Bracing3.9 Truss BracingResults of Bad Bracing
56
3.9 Permanent Bracing3.9 Permanent Bracing
Bottom Chord PlaneBottom Chord Plane
Top Chord PlaneTop Chord Plane
Web PlaneWeb Plane
57
3.9 Top Chord Bracing3.9 Top Chord Bracing
58
3.9 Bottom Chord Bracing3.9 Bottom Chord Bracing
59
3.9 Bottom Chord Bracing3.9 Bottom Chord Bracing
60
3.9 Web Plane Bracing3.9 Web Plane Bracing
61
3.9 Web Permanent Bracing3.9 Web Permanent Bracing
Compression Web BracingCompression Web Bracing
62
3.9 Web Buckling3.9 Web Buckling
63
3.9 Web Bracing3.9 Web Bracing
64
3.9 Web Reinforcement3.9 Web ReinforcementBRACE
WEB
T-BRACET-BRACE
65
3.9 Construction Loads 3.9 Construction Loads
66
3.9 Construction Loads3.9 Construction LoadsNever Stack Materials on Unbraced or
Inadequately Braced Trusses
67
3.9 Construction Loads3.9 Construction LoadsNever Stack an Unreasonable Amount
of Material on the Trusses
68
3.9 Construction Loads3.9 Construction LoadsLoads with No Bracing
69
3.9 Construction Loads3.9 Construction LoadsDangers of Overloading
70
ContentsContents1.0 Purpose of Bracing2.0 Design Responsibilities3.0 Design Information4.0 Special Conditions5.0 Diagonal Bracing6.0 Top Chord Bracing7.0 Bottom Chord Bracing8.0 Summary
71
1.1 Guideline Document1.1 Guideline DocumentCommentary for Permanent Bracing of Metal Plate Connected Wood Trusses
by John Meeks, P.E.
72
1.2 Loads in Plane1.2 Loads in Plane
73
1.3 Lateral Loads1.3 Lateral Loads
WIND SEISMIC
LO
AD
74
1.4 Truss System Bracing1.4 Truss System Bracing
75
1.5 Truss Placement Plan1.5 Truss Placement Plan
76
1.0 Quiz1.0 Quiz
77
2.0 Design Responsibilities2.0 Design Responsibilities1.0 Purpose of Bracing2.0 Design Responsibilities3.0 Design Information4.0 Special Conditions5.0 Diagonal Bracing6.0 Top Chord Bracing7.0 Bottom Chord Bracing8.0 Summary
2.1 Design Responsibilities2.1 Design Responsibilities
Section 2.2 for Building Designer Responsibilities
79
2.1 Design Responsibilities2.1 Design ResponsibilitiesANSI/TPI/WTCA 4-2002
80
2.2 Truss Designer2.2 Truss Designer
81
2.2 Component Design2.2 Component Design
82
2.2 Truss-to-Truss Connections2.2 Truss-to-Truss Connections
83
2.2 Permanent Web Bracing2.2 Permanent Web Bracing
84
2.2 Truss Submittal2.2 Truss Submittal
85
2.3 Building Designer2.3 Building Designer
86
2.3 Brace Design2.3 Brace Design
87
2.3 Brace Load Transfer2.3 Brace Load Transfer
88
2.3 Lateral Load Transfer2.3 Lateral Load Transfer
89
2.3 Ceiling Diaphragm2.3 Ceiling Diaphragm
90
2.3 Roof Diaphragm2.3 Roof Diaphragm
91
2.4 Truss-to-Girder2.4 Truss-to-Girder
Figure 1 from the Commentary
92
2.4 Truss-to-Bearing2.4 Truss-to-Bearing
Figure 1 from the Commentary
93
2.0 Quiz2.0 Quiz
94
3.0 Design Information3.0 Design Information1.0 Purpose of Bracing2.0 Design Responsibilities3.0 Design Information4.0 Special Conditions5.0 Diagonal Bracing6.0 Top Chord Bracing7.0 Bottom Chord Bracing8.0 Summary
95
3.1 Truss Design Info3.1 Truss Design Info
96
3.2 Bearing Info3.2 Bearing Info
97
3.3 Axial Forces3.3 Axial Forces
98
3.0 Quiz3.0 Quiz
99
4.0 Special Conditions4.0 Special Conditions1.0 Purpose of Bracing2.0 Design Responsibilities3.0 Design Information4.0 Special Conditions5.0 Diagonal Bracing6.0 Top Chord Bracing7.0 Bottom Chord Bracing8.0 Summary
100
4.0 Special Conditions4.0 Special Conditions System Bracing and
Special Conditions on p.8
101
4.1 Horizontal Truss4.1 Horizontal Truss
Figure 2 from the Commentary
WIND
102
4.1 Horizontal Truss4.1 Horizontal Truss
Figure 2 from the Commentary
103
4.2 Gable End Frame4.2 Gable End Frame
104
4.2 Structural Gable End4.2 Structural Gable End
105
4.3 Gable End Brace Location4.3 Gable End Brace Location
106Figure 3 from the Commentary
4.4 Gable End Brace Design4.4 Gable End Brace Design
Full depth
Mid-depth
107
4.5 Reinforcement4.5 Reinforcement
108
Scab Reinforcement
Reinforcement
WEB
Reinforcement
WEB
T-Reinforcement
4.5 Reinforcement Options4.5 Reinforcement Options
Figure 4 Modified from the Commentary
WEB
L-Reinforcement
Reinforcement
SpeciallyDesigned MetalReinforcement
WEB
Metal Reinforcement
109
4.0 Quiz4.0 Quiz
110
5.0 Diagonal Bracing5.0 Diagonal Bracing1.0 Purpose of Bracing2.0 Design Responsibilities3.0 Design Information4.0 Special Conditions5.0 Diagonal Bracing6.0 Top Chord Bracing7.0 Bottom Chord Bracing8.0 Summary
111
5.1 Permanent Web Bracing5.1 Permanent Web Bracing
112
5.1 Location of Web Brace5.1 Location of Web Brace
113
5.1 Location of Web Brace5.1 Location of Web Brace
114
5.1 Diagonal Braces5.1 Diagonal Braces
115
5.1 Info on Diagonal Braces5.1 Info on Diagonal Braces
116
5.2 Two Percent Rule5.2 Two Percent Rule
117
5.3 Spacing of Diagonal Bracing5.3 Spacing of Diagonal Bracing
Procedure detailed in DSB-89: Recommended Design Specificationfor Temporary Bracing of Metal Plate Connected Wood Trusses
Figure 5 from the Commentary
118
5.4 Bracing Minimums5.4 Bracing Minimums
119
5.5 Maximum L/d Ratio5.5 Maximum L/d Ratio
805.1120
dL
120
5.6 System Sway5.6 System Sway
HORIZONTALFORCE
121
5.7 Sway Bracing 5.7 Sway Bracing << 4' oc 4' oc
Figure 6a from the Commentary
122
5.7 Sway Bracing Locations5.7 Sway Bracing Locations
123
5.7 Sway Bracing > 4' oc5.7 Sway Bracing > 4' oc
Figure 6b from the Commentary
124
5.0 Quiz5.0 Quiz
125
6.0 Top Chord Bracing6.0 Top Chord Bracing1.0 Purpose of Bracing2.0 Design Responsibilities3.0 Design Information4.0 Special Conditions5.0 Diagonal Bracing6.0 Top Chord Bracing7.0 Bottom Chord Bracing8.0 Summary
126
6.0 Top Chord Bracing6.0 Top Chord Bracing
127
6.1 Multi-piece Truss6.1 Multi-piece Truss
ft 13Height Max.
128
6.1 Piggyback Assembly6.1 Piggyback Assembly
Supporting or Carrying Truss
Supported or Cap Truss
129
6.1 Supporting Truss Top Chord6.1 Supporting Truss Top Chord
spacing
CLBsthickness
130
6.1 Supporting Truss Bracing6.1 Supporting Truss Bracing
Figure 7 from the Commentary
131
6.1 Bracing Options6.1 Bracing Options
132
6.2 Top Chord Extensions6.2 Top Chord Extensions
StructuralTop Chord Extensions
Figure 8a from the Commentary
133
6.3 Top Chord Filler6.3 Top Chord Filler
Figure 8b from the Commentary
Filler
134
6.4 Bottom Chord Filler6.4 Bottom Chord Filler
Figure 9 from the Commentary
Filler
Bracing
135
6.5 Filler for Roof Slope6.5 Filler for Roof Slope
Figure 10 from the Commentary
Slope
136
6.5 Blocking for Top Chord6.5 Blocking for Top Chord
137
6.6 Valley Sets6.6 Valley Sets
138
6.6 Valley Framing6.6 Valley Framing
139
6.6 Valley Framing6.6 Valley Framing
140
6.7 Hip Trusses6.7 Hip Trusses
141
6.7 Hip Truss Bracing6.7 Hip Truss Bracing
Figure 12 from the Commentary
Locations of CLBs
142
6.8 Mono Pitch Trusses6.8 Mono Pitch Trusses
LOAD
Figure 13 from the Commentary
143
6.9 Top Chord Sheathing6.9 Top Chord Sheathing
144
6.10 Top Chord Purlins6.10 Top Chord Purlins
145
6.10 Purlin Options6.10 Purlin Options
Figure 14 from the Commentary
146
6.11 Roof Diaphragm6.11 Roof Diaphragm
Figure 15a from the Commentary
147
6.11 Roof Diaphragm6.11 Roof Diaphragm
Figure 15b from the Commentary
148
6.0 Quiz6.0 Quiz
149
7.0 Bottom Chord Bracing7.0 Bottom Chord Bracing1.0 Purpose of Bracing2.0 Design Responsibilities3.0 Design Information4.0 Special Conditions5.0 Diagonal Bracing6.0 Top Chord Bracing7.0 Bottom Chord Bracing8.0 Summary
150
7.1 Bottom Chord Sheathing7.1 Bottom Chord Sheathing
151
7.2 Bracing also Required?7.2 Bracing also Required?
Figure 16 from the Commentary
Diagonal Bracing
ContinuousLateralBracing
152
7.3 Bracing Locations7.3 Bracing Locations
80dL that so Designer Trussby S, Spacing,
Diagonal Bracing
Figure 16 from the Commentary
153
7.4 Special BC Bracing7.4 Special BC Bracing
Cantilever
154
7.4 Special BC Bracing7.4 Special BC Bracing
Multiple Bearing
155
7.4 Special BC Bracing7.4 Special BC Bracing
Wind Uplift
156
7.5 Floor Truss Bracing7.5 Floor Truss Bracing
Strongback bridgingDeflection criteria above L/360Deeper truss, Length/Depth=20 or less
Figure 17 from the Commentary
157
7.0 Quiz7.0 Quiz
158
8.0 Summary8.0 Summary1.0 Purpose of Bracing2.0 Design Responsibilities3.0 Design Information4.0 Special Conditions5.0 Diagonal Bracing6.0 Top Chord Bracing7.0 Bottom Chord Bracing8.0 Summary
159
8.1 Truss Member Bracing8.1 Truss Member Bracing
160
8.2 Truss Designer8.2 Truss DesignerSpecifies web bracing location only
161
8.3 Building Designer 8.3 Building Designer Designs bracing system
162
8.4 Bracing Design8.4 Bracing DesignUp to 4 ft o.c.2x_ stress rated materialFasten with min. 2-16d common nails
163
8.5 Wide On Center Spacing8.5 Wide On Center Spacing
164
8.6 CLB Overlap8.6 CLB Overlap
165
8.7 Floor Assemblies8.7 Floor AssembliesStrongbacks and ribbon band
10 ft o.c.
10 ft o.c.
166
8.0 Quiz8.0 Quiz
167
WTCA is the Information SourceWTCA is the Information Source
168
Structural Building Components Structural Building Components MagazineMagazine
169
www.woodtruss.comwww.woodtruss.com
170
WTCA HomepageWTCA Homepage
171
™
Wood Truss Council of AmericaWood Truss Council of America
Email [email protected]
Phone 608-274-4849