Structural Calculations
Project Lucknow School
Project Number 15‐351
Document Control
Date Version Extent of Revision Status
14 January 2015 A Original Review
Calculations prepared for Timely Consultants and SDC Design Tim Pike Sigma Consulting Engineers Ltd CPEng 161118
Alterations are proposed to two existing buildings at Lucknow School and a review of the wall bracing is required. The two buildings are the library and administration blocks. Library The library was constructed in stages in 2001, 2004 and 2008. Drawings are available for all three stages and it can be determined that the three sections of wall that are to be altered do not include any bracing elements. See the marked up plan on the following page.
Administration Building
The administration building was altered in 1997 (Michael Newby Associates) and bracing calculations are available. The current alterations include the removal of walls that incorporate bracing elements so it is necessary to evaluate the building. Some 1997 elements will remain. BRANZ Maps suggest a “Medium” wind zone Earthquake Zone 3 Building Importance Level 2 Refer to attached Gib Ezy‐Brace spreadsheet for demand calculation Bracing demand = 696BU EQ and 418BU Wind Along, 542BU Wind Across
Existing wall bracing along = 500BU wind and 440BU EQ
Existing wall bracing across = 650BU wind and 607BU EQ
Add 1‐BL1 (H) x 3.6 m in along direction and 1‐BL1 (H) x 3.2m in across direction to result in:
Existing wall bracing along = 961BU wind and 814BU EQ
Existing wall bracing across = 1060BU wind and 940BU EQ
Add 2‐BL1(H) elements to front wall also to ensure that all of the external walls include some wall
bracing. See attached marked up floor plan
Client Lucknow School Project No 15-351
Project Library & Admin Alterations Revision A
Location Elliot Cres Havelock North Date 14 January 2015
Designer SDC Design Ltd Page No 01
Beam over Staffroom 150PGC beam designed by Flexure Ltd in 2005, to span 4.1 metres. Wall removal means that the beam is now required to span 5.2 metres. Utilise Flexure Ltd information. Beam supports a point load 2.4 metres from the exterior wall – design as being central in span G = 5.9 kN Q = 4.9 kN Wu = 10.8 kN G+Q = 10.8 kN 1.2G+1.5Q = 14.4 kN 0.9G‐Wu = ‐5.5 kN M* = (14.4*5.2/4) = 19 kNm 150PFC: ΦMb = 22 kNm (mid‐span restraint) and deflection (G) = 19mm = span/274 No Good 180PFC: ΦMb = 27 kNm and deflection (G) = 11mm = span/460 OK Existing 150PFC is inadequate and needs to be replaced with a 180PFC. Utilise the details prepared by Flexure Ltd – see following pages.
Client Lucknow School Project No 15-351
Project Library & Admin Alterations Revision A
Location Elliot Cres Havelock North Date 14 January 2015
Designer SDC Design Ltd Page No 04
Roof Structure to Reception 360x88 Prolam ridge beam specified by designer to span over reception space. Support on 90x90 timber posts in accordance with section 9 of NZS 3604:2011. Ridge beam to cantilever at both ends. The front support post is supported on a lintel that spans over the front wall entry door and adjacent windows, and the design of this follows: Lintel span = 4.7 metres Bearing reaction = 8.5 kN and uplift reaction = 3.4 kN (from Prolam summary) Using Prolam calculator: 315x90 Prolam lintel required See data on following pages.
Client Lucknow School Project No 15-351
Project Library & Admin Alterations Revision A
Location Elliot Cres Havelock North Date 14 January 2015
Designer SDC Design Ltd Page No 07
PRODUCER STATEMENT Tasman Consulting Engineers Limited has been engaged by Prowood to provide design services for the development of the Prolam Online calculator. The design has been carried out using sound and widely accepted engineering principles to the requirements of AS/NZS1170:2002, NZS3603:1993 and NZS3604:2011 using the timber properties for GL8, GL12 and GL17 glulam and LVL15. I believe on reasonable grounds that the above design will meet the requirements of clauses B1/VM1 of the Building Code Documents.
David King ME (civil, MIPENZ CPEng (no 145511) IntPE
For Tasman Consulting Engineers, PO Box 3631, Richmond, NELSON 7050 March 2015
Lucknow School 15-35114 January 2016
Customer/Project: Lucknow School 15-351Physical Address: Elliot Crescent Havelock North
Designer: Tim Pike, Sigma Consulting Engineers LtdPO Box 14-039 Mayfair, Hastings 4159 E: [email protected] P: 068700669
Lucknow School 15-35114 January 2016
SN-R10047078
Admin Area Ridge BEamProlam Ridge Beam Supporting Roof and Ceiling
Building Type Office
Timber Pine, Machined
Treatment H3.2
Visual Yes
Exposed Yes
Roof Pitch 20 °
Roof Span 6.00 m
Lintel Span 5.80 m
Use Prolam PLVL8H3-400100 360 x 88mm PL8
Roof Weight Light with Ceiling
Roof Load 0.40 kPa
Live Load 0.25 kPa uniform
1.40 kN concentrated
Wind Zone Medium (37.0 m/s)
Snow Region No Snow
Capacity Ratio 1.8
Long Term Deflection 2.7 mm
Max. Bearing Reaction 8.5 kN
Load Combination 1.2G + 1.5Q
Minimum Bearing Length 35 mm
Uplift Fixing Requirements 3.375 kN Characteristic Load
PRODUCER STATEMENT Tasman Consulting Engineers Limited has been engaged by Prowood to provide design services for the development of the Prolam Online calculator. The design has been carried out using sound and widely accepted engineering principles to the requirements of AS/NZS1170:2002, NZS3603:1993 and NZS3604:2011 using the timber properties for GL8, GL12 and GL17 glulam and LVL15. I believe on reasonable grounds that the above design will meet the requirements of clauses B1/VM1 of the Building Code Documents.
David King ME (civil, MIPENZ CPEng (no 145511) IntPE
For Tasman Consulting Engineers, PO Box 3631, Richmond, NELSON 7050 March 2015
Lucknow School 15-35114 January 2016
Customer/Project: Lucknow School 15-351Physical Address: Elliot Crescent Havelock North
Designer: Tim Pike, Sigma Consulting Engineers LtdPO Box 14-039 Mayfair, Hastings 4159 E: [email protected] P: 068700669
Lucknow School 15-35114 January 2016
SN-R10047079
Lintel supporting Ridge BeamProlam Lintels Supporting Ridge Beam
Building Type Office
Timber Pine, Machined
Treatment H1.2
Visual No
Exposed No
Roof Pitch 20 °
Eaves 600 mm
Position of Girder Truss on Lintel 2.35 m
Setback 7.00 m
Supported Truss Span 5.70 m
Lintel Span 4.70 m
Use Prolam PL8H1-350100 315 x 90mm PL8
Roof Weight Light with Ceiling
Roof Load 0.40 kPa
Live Load 0.27 kPa uniform
1.40 kN concentrated
Wind Zone Medium (37.0 m/s)
Snow Region No Snow
Capacity Ratio 1.0
Long Term Deflection 6.1 mm
Max. Bearing Reaction 10.4 kN
Load Combination 1.2G + 1.5Q
Minimum Bearing Length 35 mm
Uplift Fixing Requirements 4.625 kN Characteristic Load
Draft Not ForConstruction
4-1997 bracing elements to this line200BU (EQ) and 240BU (wind)
1997 bracing element132BU wind, 120BU EQ
1997 bracing element156BU wind, 144BU EQ
1997 bracing element104BU wind, 96BU EQ
1997 bracing element156BU wind, 144BU EQ
1997 bracing element156BU wind, 144BU EQ
2-1997 bracing elements to this line199BU (EQ) and 206BU (wind)
New BL1(H) x 3.6m bracing element461BU wind and 374BU EQ
New BL1(H) x 3.2m bracing element410BU wind and 333BU EQ
Extg 250x100 beams
360x88 Prolam Ridge Beam
315x90 PL8 Lintel
Valley Rafters (NZS 3604:2011)
Add 2-BL1(H) bracingelements to front wall toprovide 108BU wind and122BU EQ