Universidad  de  Chile  Presenta0on  San0ago,  26th  April,  2011  

John  Chapman  School  of  Architecture  &  Planning  University  of  Auckland  jb.chapman@auckland.ac.nz  

Timber Building Studies Group School of Architecture & Planning, NICAI Faculty The University of Auckland

www.creative.auckland.ac.nz/uoa/timber-studies-group

The intention of the Timber Building Studies Group is to contribute to the development of multi-level timber commercial buildings

Staff  Members:  

John  Chapman,  Senior  Lecturer  Dr  George  Dodd,  Head  of  AcousBc  TesBng  Service    

Assoc  Prof  Uwe  Rieger  

Prof  Andrew  Barrie  

Timber  Buildings  from  New  Zealand  

•  Old  Government  House,  Wellington.  

St  Paul's  Church,  

Wellington,  NZ  

Built  130  years  ago  English  style  

Small  roof  truss  secBons  •  Small    

Te  KooB’s  Marae,    OpoBki  Maori  meeBng  house,  130  years  old  

TradiBonal  Timber  carving  tells  history  of  the  tribe  

Historic  mulB-­‐storey  buildings  up  to  7  stories,  NZ      Built  1920’s  

Britomart  buildings,  Custom  St,  Auckland.    Images  -­‐  Heritage  Hotel,  Hobson  St,  Auckland  

Recent  MulB-­‐storey  in  NZ  

•  Upper    image,  Auckland  

•  Lower  image  Wellington  

•  Engineering  by  Warwick  Banks    

90%  of  houses  in  NZ  are  Bmber  frame  construcBon  

Pre-­‐nail  frames  common  in    NZ  

•  The  3mber  frames  are  made  in  a  factory  and  trucked  onto  site.  

Industries  around  Bmber  building  

•  Upper  image,  glulam  factory  –  70%  glulam  is  exported  

from  NZ’s  largest  factory,  McIntosh  Timber  Laminates  Ltd  

•  Lower  image,  driving  3mber  pole  piles  –  NZ  exports  pile  driving  

equipment  

Modern  European  Timber  Buildings  Europe  has  tradi3ons  in  3mber  building  

Hazelwood  School,  UK  Asian  styling  

Beams    built-­‐up  &  intersecBng  Columns  with  pin  joints  

Carpenters  School,  Germany  3D    trusses  

Span  along  building  JoinBng  with  steel  plate  and  steel  pins  

Timber  Warehouse  &  Showroom  (1995),  Herzag,  Germany,  by  Baumschlager  &  Eberle  

External  walls  curving  horizontally  &  verBcally  

Timber  Warehouse  &  Showroom  

(1995),  Herzag,  Germany    

Hidden  moment  joints  at  eaves  

Steel  plate  in  joint  

Steel  pins  to  transfer  moments  

Glulam  advantages  

–  predictable  strength  /  s1ffness  proper1es  

–  Can  be  made  deeper  and  longer  

–  Thinner  laminates  /  more  curve  

o  

St  Benedict  Chapel  Switzerland  

Slender  columns  –  short  Ridge  beam  tapers  

Arched  roofs.      Economical,  minimal  Bmber  

LH  image  -­‐  Marlowe  Academy.,  UK  RH  Image  –  Pool,  Germany,  by  Julius  Naberer  

Expo  Hanover  Julius  NaMerer  

Timber  members  are  mul3ple  layers  of  thin  3mber,  intersec3ng  each  other  With  many  pieces  of  3mber,  the  effect  of  weak  pieces  is  much  reduced  

Julius  Naberrer  www.naMererbcn.com  

Hannover  Expo  2000   Saville  building,  Windsor  

Cross  laminated  Timber  Building  Systems  

 CLT  Systems              Background    

 Timber  buildings  to  a  height  of  9  storeys  have  recently  been  built  in  Europe  which  rely  on  prefabricated  CLT    or  ‘cross-­‐laminated  Bmber’  panels.  Timber  stress  around  4mPa  max.    

                       Murray  Grove  Apartments,  London                                      CLT  shear  wall  and  floor  panels  

KLH UK Ltd is part of KLH Massivholz GmbH, Austria

Katsch,  AT  

Orsa,  S  

KLH = KreuzLagenHolz

engl. = Cross Laminated Solid Timber Panels

16.55m3.0 m

500mm

pressure 5 to 7 kg/cm2equivalent 500 kN/m2

maximum size after cutting : 2.95m (2.98) x 16.5m

maximum lengthmaximumwidth/height

production method in physical press :

Fire Performance

• Calculated on charring rate

• Top layer burns at 0.67mm / min; subsequent layers at 0.76mm / min

• Performance can be improved by allowing for another sacrificial layer of timber or / and with additional layers of plasterboard

• Generally 3-layers boards ( layer thickness min 30mm ) can achieve REI 30; 5-layer boards REI 60

Pinus radiata is suitable for ‘massive’ timber elements because it

• Glues easily

• Finishes well and has good appearance– A smooth sanded finish is

easily achieved

• Is not limited by its low strength– Massive panels in cross

laminated systems have low maximum bending stresses of around 5 N/sq.mm

TBSG Project: Study CLT Systems Focus

Our research focus: ‘Can systems be developed for CLT buildings to resist horizontal wind and earthquake loads that allow more open and unrestricted spaces than current CLT buildings which require frequent shear walls ?’

Systems studied:A) Frames, of prefabricated CLT columns and beams that are fix jointed on siteB) Circular Core, of prefabricated CLT panels connected on site to form a stiff central tubeC) Shear Walls, of prefabricated CLT shear panels, 4 no. only

TBSG Project: Study CLT Systems Conclusions

Conclusions of study –Timber stresses are relatively low and the systems are suited to ‘cross laminated timber’ construction

- CHH Ltd are looking to establish a CLT plant in Sydney to service Australasia- CLT uses mainly timber below structural grade- Requires relatively low numbers of carpenters (due to prefabrication)

Pole Building Systems

Poles used for traditional buildings in Japan

Todiji Temple, Nara, Japan• Building, 1703• Replaced 50% bigger building, 752

Round Timber• natural tree trunks with the

bark removed by peeling or shaving

– Round Timber also known as poles, logs, & stems

• Pacific Island meeting House

Pinus Radiata Round Timber used

successfully as structural elements for

over 50 years in NZ

• Minimal in-service problems

– 5m retaining wall– 7.5 tonne / pole– 20mpa bending stress

Round Timber for foundations & pole platforms

Uniform Diameter Roundwood- pole machined to form a uniform diameter

-Overcomes problem of pole taper and uneven surface

-Allows regular joint cleats

Uniform diameter round timber for

Telecommunication Towers

- up to 32m high & 200km/hr winds- 30 tonne member axial loads

Poles in recent European Architecture

• Poles remind the viewer of trees and nature.

• Mont-Cenis Academy (1999), Jourda & Perraudin

TBSG  Research  Project:  Proper3es  of  pinus  radiata  poles                              Background  

•  This  research  due  to  weakness  of  pole  joints  in  tes5ng  (for  6  storey  building  project)  

•  Five  suppliers  located  from    typical  growing    areas,  between  top  of  N.  Island  and  top  of  S.  Island,  supplied  10  poles  each  

•  Bending  tests  carried  out  at  Scion,  Rotorua.  Compression  tests  done  at  UoA    

Proper3es  of  pinus  radiata  poles                                                            Results  

•  Table  2  from  code  NZ3604,  and  gives  the  minimum  required  proper5es  for  poles  

•  Table  3  shows  the  true  proper5es  of  the  poles  

•  Pole  proper5es  only  60%  of  minimum  proper5es  published  in  the  NZ  code  

Proper3es  of  pinus  radiata  poles                                                          Conclusions  

•  Changes  in  physical  proper5es  due  to  changes  in  forest  management  

•  In  the  past  trees  planted  1m  apart  –  Trees  competed  

•  Small  knots    

•  Now  trees  grow  4m  apart  –  Pruned  region  for  

lumber.  Poles  come  from  above  pruned  region  .

•  Large  knots  

Econobuild  Structures  

Timber  arches,  nail-­‐plated  together  Economical  industrial  buildings  

University  of  Canterbury  LVL  Frame  research  

Timber  Bridges  for  Road  &  Rail  Very  efficient  structures  

70,000  built  in  Australia  &  4,000  in  NZ  

Historic  Timber  Road  &  Rail    Bridges,  NZ  

Upper  Image  -­‐  Manganuku  Stream  Bridge,  span  25m,  built  1920’s,  Waioeka  Gorge,  Optoki.    Howe  truss  structure,  2000  Howe  truss  bridges  built  in  NZ.    

Rail  Bridge,  Williamstown,  Australia  

New  Pole  Bridge  Robinvale,  Australia    Eucalypt  poles  

New  road  bridge,  Sneek,  Holland  Made  from  pinus  radiata,  non-­‐toxic  chemical  treatment  

Study  area  2:  

 Sound  resistant  0mber  floors    

 1st  Project:      Pole  Joists    General  Arrangement  

•  Poles  joists  used  to  reduce  costs    –  based  on  tes[ng  26  previous  floors  with  UoA  and  Scion  

 1st  Project:      Pole  Joists    Tes3ng  

•  Floor  test  rig,  with  pole  joists  placed,  and  tes[ng  finished  floor    

 1st  Project:      Pole  Joists    Results  

•  Floor  complies  with  NZ  code  for  airbourne  &  impact  sound  resistance  •  Not  taken  up  by  industry    

 2nd  Project:    Timber-­‐concrete  composite  floor    Plan  &  Sec3on  

•  180mm  thick  3mber  panels  and  a  65mm  thick  concrete  topping.  

•  Timber  below  structural  grade  

 2nd  Project:    Timber-­‐concrete  composite  floor    Eleva3on    &  Proper3es  

-­‐  Rodents  cannot  live  in  

-­‐  Good  fire  and  water  resistance  

-­‐  Concrete  slab  is  heat  sink  

-­‐  Reduced  CO2  emissions  

-­‐  U3lises  90*45  non-­‐  structural  3mber.  Timber  has  low  stresses,  around  4mPa  

-­‐  Possibly  good  sound  resistant  proper3es  and  economical  ($180/sq.m)  

-­‐  Able  to  contain  services  

 2nd  Project:    Timber-­‐concrete  composite  floor    Test  Floor  

2nd  Project:    Timber-­‐concrete  composite  floor  Final  Arrangement  

Acous[c  test  results  comply  with  NZ  codes  when  floor  topping  increased  to  100mm  thick:  

–  Floor,  with  carpet  on  top  surface,  passes  NZ  code  for  impact  sound  

–  Floor  passes  NZ  code  for  airbourne  sound    

3rd  Project:    Timber-­‐concrete  composite  floor                  Vibra3on  control  

S[ffness  helps  floor  vibra[on  

 -­‐  reduces  deflec[on  

Mass  does  not  help  floor  vibra[on  

-­‐  Vibra[on  has  more  ‘momentum’  with  increased  mass  

High  s[ffness  and  low  mass  do  not  go  together    

-­‐  The  two  factors  need  to  be  balanced  

3rd  Project:    Timber-­‐concrete  composite  floor                  Proposed  New  Arrangement  

Floor  uses  315mm  deep  *  90mm  wide  joists  at  900mm  centres,  [mber  ceiling    

Compared  to  the  previous  floor  this  floor  is  –  Lighter  by  33%  and  more  

economical    

–  Beeer  vibra[on  characteris[cs  

–  Stronger  and  can  span  to  9m  easily  

3rd  Project:    Timber-­‐concrete  composite  floor                  Shear  connec3on  

The  floor  hopefully  fails  at  this  joint  and  failure  is  gradual  

Over  the  following  months,  this  joint  will  be  tested  for  strength  and  slip  within  joint  

Strength  of  [mber  to  concrete  bearing  20kN  approx;  inclined  screw  17kN  approx.  

New  research  ideas  

21  Storey  Timber  Building  

•  Building  based  on  yacht  mast  structure  and  CLT  panel  technology    

•  ‘Mast’  is  tube,  11m  diameter,  12  no.  CLT  panels  3.95m  wide  *  280mm  thick  

•  Structure  can  support  sta5c  wind  load  of  2.5kPa.  Can  it  be  made  duc5le  and    support  earthquake  loads?  

Gracias