woodsolutions symposium...itw construction asia pacific residential division woodsolutions symposium...

ITW CONSTRUCTION ASIA PACIFIC RESIDENTIAL DIVISION

WoodSolutions Symposium1st December 2016

Session 2E: Lightweight Floor & Wall Design

Presented by:Nick Cui

Pryda Australia

How are current timber buildings designed?


Most timber structural design systems that are available can readily cope with the

engineering requirements from a design perspective for these types of buildings.


Design – Architectural /

Engineering

Specification

Fabricator/

Manufacturer

Installation

Compliance

Building concept

Where we currently fit in the process…


Design – Architectural /

Engineering

Specification

Fabricator/

Manufacturer

Installation

Compliance

Building concept

What about panelisation?


Keep in mind as we move forward…

Current timber framing

• 3 to 4 storey category widely accepted

• Mostly pre-fab frame, floor & roof

• Panelised floors & walls at infancy

Mid-rise opportunity

• 4 to 5 storey category (more for hybrid)

• Different mind set will be needed

• Panelisation may be key to compete here


FLOOR TRUSSES & CASSETTES


Open web floor trusses…

Longreach (timber web)

• Any depth, typically 200–600mm

• Premium performance & stiffness

• Set downs – 35/45mm typical.

• Span up to 7.4m (400mm 90x45 F17)

Pryda Span (metal web)

• 250, 300 & 400mm (nominal)

• Lightweight & economical

• Set downs – 35/45mm typical.

• Span up to 6.9m (400mm 90x45 F17)


Multiple load areas…

More varied dead & live loads

Engineer to specify on drawings

Load areas drawn on model

Trusses designed for dead/live loads


Dynamic performance…

Imposed load check(Absolute deflection under Q)

EC5 METHODS:

Footstep induced vibrations(Fundamental frequency > 8 Hz)

Low-frequency effects (UKNA to EC5)(Step frequency effect)

FURTHER CONSIDERATIONS:

Effect of supporting elements…


Flooring lining options…

Particleboard/OSB/plywood flooring

FC Sheet/concrete for wet areas

Promat/Hebel/INEX Floor

Other materials also accommodated


Ceiling lining options…

Plasterboard/FC sheet etc…

Insulation/fire/acoustics

Services – within/below floor

Open panel method currently used


End types…

Many end types available

Only a handful may apply

Consideration for cassette stability

Consideration for crushing etc…

Timber Beam

Pryda Joist

Hanger Supporting

Truss

STANDARD END DETAIL TYPE 6

Waling Plate

Min. Bearing 30mm

on Waling Plate


Skew Nails Preferable Into

Beam to Restrain Bottom Chord

Min. Bearing 30mm


TYPICAL BEAM SUPPORT FIXING

OPTION 1

2/75 x 3.75mm

Dia. Skewed Nails

Self Drilling Screws CSK

Heads

TYPICAL PLATE SUPPORT FIXING

OPTION 2

Pryda Multigrip With Min. 3/35 x

3.15mm Dia. Pryda Nails Per Tab

OPTION 1

2/75 x 3.75mm

Dia. Skewed Nails

Min. Bearing 30mm on

Primary Bearing Point



Manufacturing…

2.7m wide to 3.5m wide +

9m long to 12m long +

Depends on linings & transport

Designed & supplied by fabricator


Lifting systems…

Straps & slings

Hooks, chains, load rings

Proprietary lifting systems

Typically 4 point lifting


WALL FRAMES & PANELS


Prefab or site framed…

Prefab generally more common

Typically 90mm wide (3–4 storeys)

Cladding/finishes completed on site

Longer overall installation/build time


Panelised wall frames…

Emerging option but gaining traction

“Open panels” more common. No internal linings, bulk insulation or services

Options: sheathed, breather membrane, external cladding & windows/doors fitted

Faster overall installation/build time


External cladding options…

Sheathed only with Ply, OSB etc…

Lightweight w/board, foam, FC sheet

Hebel panels, James Hardie claddings

Brickwork & rendered finishes


Bracing systems…

Higher bracing & tie down demands

Conventional & special systems

Truss brace system built into walls

Trussed portals, moment connections


Issues to overcome…

Creep, shrinkage, crushing

Lateral stability & connections

Wind & EQ (tie downs, ductility etc…)

Robustness/Disproportionate collapse


TOOLS & REFERENCES


Literature & Design Guides…


Pryda technical support…

• Design office support & advice

• Preliminary truss designs/feasibility studies

• Product support and technical advice

• Links to fabricators – quoting & supply

What to take away from this session


• 4 to 5 storey “sweet spot” for lightweight timber structure

• 5 to 8 storey – Consider “Hybrid” CLT & light timber

• Panelised solutions very promising but still early stages

• Fabrication & supply chain – Need guidance & confidence

• New systems & techniques – Look to overseas?

• Collaboration between all parties essential to move forward


QUESTIONS?

woodsolutions symposium...itw construction asia pacific residential division woodsolutions symposium...

Documents