structural design of mass timber framing systems

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1 structural design of mass timber framing systems nwwood design symposium -seattle davin lewis, p.e., p.eng. fast +epp july19, 2018 Disclaimer: This presentation was developed by a third party and is not funded by WoodWorks or the Softwood Lumber Board

2 Copyright Materials This presentation is protected by US and International Copyright laws. Reproduction, distribution, display and use of the presentation without written permission of the speaker is prohibited. Fast + Epp 2018

3 The Wood Products Council is a Registered Provider with The American Institute of Architects Continuing Education Systems (AIA/CES), Provider #G516. Credit(s) earned on completion of this course will be reported to AIA CES for AIA members. Certificates of Completion for both AIA members and non-aia members are available upon request. This course is registered with AIA CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product. Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation.

4 course description Mass timber structural framing systems have high strength-to-weight ratios, are dimensionally stable, and are quickly becoming systems of choice for sustainably minded designers. This presentation will provide a detailed look at the structural design processes associated with a variety of mass timber products, including glued-laminated timber (glulam), cross-laminated timber (CLT), and naillaminated timber (NLT). Applications for the use of these products in gravity force-resisting systems under modern building codes will be discussed. Other technical topics will include use of mass timber panels as two-way spanning slabs, connection options and design considerations, and detailing and construction best practices.

5 At the end of this course, participants will be able to: 1. Discuss mass timber products and building systems and their possibilities as structural framing. 2. Compare structural properties and performance characteristics of mass timber products and review their unique design considerations. 3. Review structural design steps for members and connections in common mass timber framing systems. 4. Highlight structural detailing best practices to address items such as shrinkage and expansion, load path continuity, and speed of construction. learning objectives

6 about our firm + Vancouver Canada + Frankfurt Germany + New York USA + Seattle USA + Edmonton Canada

7 wood properties design standards gravity framing lateral systems connections overview

8 anisotropy wood properties

9 wood properties 5,000 psi A36 SPF concrete steel No.2 compression tension strength to weight

10 wood properties modulus of elasticity 1,000 2,000 ksi 5,000 psi A36 SPF concrete steel No.2 stiffness to weight stiffness

11 wood properties Source: US Forest Products Laboratory shrinkage and swelling Illustration Credit: Geoff s W oodwork

12 shrinkage and swelling wood properties

13 creep wood properties

14 wood properties Im age : IsoStore acoustics

15 wood properties design standards gravity framing lateral systems connections overview

16 codes design standards

17 design standards common holes mockups delegated design items weather protection tolerances sealers (coordinate with Division 09) structural specifications

18 wood properties design standards gravity framing lateral systems connections overview

19 gravity framing strength axial bending shear bearing post-fire? serviceability deflections (including creep) vibrations design checks

20 gravity framing nail-laminated timber (NLT) structural composite lumber (LSL, LVL) cross-laminated timber (CLT) glulam panels (GLT) wood-concrete composites decks plank decking

21 gravity framing 2x joists at 38mm (1-1/2 ) choose: depth, profile species, grade continuous vs. butt-jointed laminations NLT design

22 gravity framing detail for shrinkage and swelling NLT design

23 gravity framing design guide thinkwood.com NLT design

24 gravity framing beam on the flat A A A A A A A A A A A GLT design

25 gravity framing detail for shrinkage and swelling GLT design

26 gravity framing dimensional stability APA PRG 320 defines structural grades panel sizes vary by supplier cross laminations reduce strength and stiffness in primary span direction CLT design

27 gravity framing 2-way span capability CLT design

28 CLT design

29 gravity framing design guide thinkwood.com CLT design

30 gravity framing NLT may be most appropriate if: floor structure spans one way floor structure is curved in one direction budget is tight structure is an addition or alteration to an existing building (no crane access from above) a less manufactured aesthetic is desired decisions decisions...

31 gravity framing GLT may be most appropriate if: floor structure spans one way spans are long (no strength/stiffness reduction as for NLT with butt joints) a clean aesthetic is desired decisions decisions...

32 gravity framing CLT may be most appropriate if: floor structure needs to span in two directions (e.g. weak-axis cantilevers) a clean aesthetic is desired accommodating shrinkage and swelling during construction is difficult tight tolerances are required decisions decisions...

33 gravity framing 2x4 NLT, 3 GLT, 3-ply CLT (4 ±) 12 approx. L/40 2x6 NLT, 5 GLT, 5-ply CLT (7 ±) approx. L/20 to L/40 typical spans

34 gravity framing 2x8 NLT, 7 GLT approx. L/24 to L/36 2x10 NLT, 8 1/2 GLT, 7-ply CLT (10 ±) approx. L/22 to L/34 typical spans

35 gravity framing 2x12 NLT, 9-ply CLT (12 ±) approx. L/20 to L/28 typical spans

36 gravity framing Im age Credit: CadMakers Photo Credit: Seagate Structures openings

37 wood properties design standards gravity framing lateral systems connections overview

38 lateral systems strength shear overturning capacity design (high seismic zones) serviceability story drift wind-induced vibrations (tall structures) design checks

39 lateral systems shear walls Photo Credit: Sissi Slotover-Smutny vertical LFRS

40 lateral systems rocking walls vertical LFRS rocking moment frames Illustration Credit: PresLam

41 Photo Credit: Equilibrium Consulting wood braced frames vertical LFRS hybrids (steel or concrete LFRS)

42 lateral systems wood, steel, or concrete? walls or frames? code approvals building height and lateral load demands designing for resilience? architectural and planning considerations decisions decisions...

43 diaphragms

44 diaphragms lateral systems

45 wood properties design standards gravity framing lateral systems connections overview

46 the devil is in the details what s your philosophy? connections

47 connections in concrete Photo Credit: Reiulf Ramstad Arkitekter

48 Photo Credit: Cast Connex connections in steel Photo Credit: Ben McMillan

49 connections in steel

50 Photo Credit: Simpson StrongTie connections in stick frame

51 Photo Credits: Fire Tower Engineered Timber connections in timber frame

52 Photo Credit: TimberPlates.com Photo Credit: VicBeam Photo Credit: Uihlein-Wilson Architects connections timber? in hybrids and mass

53 connections timber? in hybrids and mass Photo Credits: Shigeru Ban Architects

54 connections make it buildable make it beautiful and don t forget about mother nature what s philosophy? your

55 column connection tallwood house at brock commons

56 column connection tallwood house at brock commons

57 column connection Photo Credit: Seagate Structures

58 column connection tallwood house at brock commons

59 2 tallwood house at brock commons 1.5 Deflection (in) Dead Loa d E las tic Li v e L oa d E l as ti c Lo n g itu d i na l Shrinkage Creep and Joint Settlement Tot al column connection

60 column connection tallwood house at brock commons