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,REFERENCE . . %
-:LtyAte ” 0 *
i4 A project / df i Vol’u.pteei%‘iA Asia’ ? ’ s
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::.,. c
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oo as a Rulldlna Material.a I-+ .
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.* I byi F.A. McClure'o, ,. n
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1 Published by:
t /. ‘Office of International Acfairs '
< , US Department of Housing and Urban Development, "
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2. 1 U.S. DEPART&NT Of: AG’R%.ULTUPE ” ’
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_., . .FOREIG&N AGkl.CUL,T(JEAL SERViCE
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“‘?,< “f’ DEPARTMENT 0~ H~.uSING’AND URBAN~DEVELOPMENT
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.:, OFFIC~~OaF”INTE~~~TlO~~L AFFAIRS
-‘Wi:iGn&n, D. C. 26410 9
3. BAMBOO AS A BUILDING MATERIAL
F.’ A. McClure’
5% formerly
L Field Service doi&ultant
c I Foreign Agricultqal Service
: / presently
Research’Associate i’n Botany ~
Smithsoniap Institutioq
,
a
,’
‘I
.- ..
,/’ -
Q
/’
,
wForeign?Agric&urG S&vi& -’ , ’;1 .; .: .,.. :;
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ited States Department of ‘hLg?icClture
Renr&.ed J&, .‘i983 -
4.
5. ;’
,;,-
‘$%is publi$@..kas
”
originally prepared and published at.,t..&&&&est of the
6;:; ; - Department of Hous$g and Urban Development U. S. D.ep.&rtment __ ,
y,, .%f Agriculture under -the Point Four those active15 ._ !
_ - ; ‘engaged or interested~ in 4he: use of bamboo.
-_ TC .iz’mn+’ DTI ayhalmtive
A.u:*cy uvr “4I “IYIUI-“-. - ----- ----_ --
.’
e - -
,“.. .
of the flUD.st@f>
.- -;-‘
. * .
_ -,J, Servf ce, United States Department
to ‘use $$hotograph b$ Hoard Dorsett. Edward ~- -;- m,-,~$
*
Fi - ph of th@@orodja *house in” the,centr& Celebes,
II R the”fr&g@ec~;, it- was‘ ori&nally published ~$,&vid Fair- , -
World GrimaRouad &y Do&,’ and pern$sston to reproduce
&Tby Scribners.. I-l. E,“.‘d‘lehn,,,Vice-~irector,‘:‘~ngineerfng Experi- ’ i’-
South &$&a,~ granted, permission , ’
‘.; &-&&t,te e&nsfvelv’fromms
-- a----- - - *
bullet&’ B&boo-&&&&ment...of Portland Ce-ment s
r
~Condrete Structires.. I&&l C. Pet&prepared @ g’line drawings t&t;beaf MS i J’.+,, $1 .-I
i _’ (, 8 ., .-.
7. -* ,, “’
’
have amply de*m,onStrated its claim to a spe-_.-_---
cial place in their evdryddy life.
As technic& cooperation continues to
single out species wit’ outstanding‘ utility,
7
and $0 te them more ‘widel’y, along
with the old and the ‘new techniques _.
essential to their practical use, the lot of
people will defi- ’
ties in spare time for sale or -exchange at I _
,,c s
the market.
.--
oped to- a. point where bamboo’s multifo If techhiques.of large-scale, mechinized j
utiljzation can be be velopedy,as., for example,, ‘.
in’th‘e,manufa6turb (If high-quality papers ‘and
* rayon‘new industrij es ar&.%ncrgase~$l national.
income m&y be be&u .ght .tg underdeveloped ;.
L , ‘-
areas. Ii. &with the 3se 1 prospects in view
bility to -h&an needs ;:it.?r;as few -i- +Ldasone~of +eJ&%- .L.:
t% pliint’kin~dom. In-the OFcident It&g the”Point Four pro-.. . .
! s,f
” as well‘as,,the Orient, ‘the ,peoples
‘,
in whose ;i
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8. .
Parts of a Hdug’e for Which Ba?nb& Are Suitable
,a
: -
I
Bamboo may;be used perior knowledge of, and devotion to, the+
parts’ of-a house.‘except principles of functional design w,ith an
chimney. Under most awareness of the possibilities. of bamboo L
as a building material of strength and
bamboo’:is actually
beauty. Being an artist as well as an ar- ,
bujlding materials, such as woo
P
cfment, galvanized iron, and pa chitect, he will appreciate the aesthetic ‘1
yccording ‘to their relative qualities of bamboo and its versatility as ‘,
i .
ability, and cost. they have been demonstrated in each area ,, ,:
The use of bamboo either as a primary, where its use has been lifted to a high plane.
1 secondary, or occasional source of building Given the right inspiration, the opportunity
material is common only in areas ‘where , to travel and tb study the best examples of
suitable bamboos ‘grow in suffitient abund- the use of bamboo in building construction, .
-. ~ ante. Importance of bamboo in any given and the cooperation of persons who know
the bamboos and thb techniques of using ‘_,,
,. !‘, larea
~ usually is de+&mined .chiefly by the
economic level of the common people and them, he will be ab e to synthesize the .’
B
other, more best features of bamboo with the! technical
improvements sug- ested by his Western * ,:
&background in func i ional design-and so ”
achieved with barn produce for each c ltural area a series .of’ j
ony pf design and a designs and plans hat will be a credit to
the architecture of,1 our age. 0..
Bamboo has several characteristics
that make it a suitable and economical
building material for house construction, 1
---Java-, and-Malaysia,- &m&owmployedY ----?--as-well as-for-the scaffolding ;iig. 1) that i ---
/
-varchitecturally~ in ways ihat are distinctive facilitates such construction:
and basically artistic. Cohen indirectly
. alludes to,,this r’ecognitiorr’bf bamboo’s 1. ,The natural un,its, or culmsi, as
.special virtues: “The principal post’ in a they are called, ar’e of a size and shape
Japcnese house‘ characterizes”the house I that make handling, storing,.and process;g
with regard to quality and construction. ‘/both convenient and ecohomi’eal. d
‘Therro’of members ar’e trussed to the post, 2. The culms have a characteristic
and enable a properlySonstructed house to phys+al-structure that g&s them a high
stand up to earthquakes and tremors. ‘The ‘strength-weight ratio. They ar&,.round or‘ ‘.--.%
writer has seen many houses in which the nearly so in cross section, and u&ally , -
principal- post is of stout bamboo, .or in ‘_ hollow, with rigid cross walls strategically : ‘; _
i..
which a stout timber post is..given more placed to preventcollapse on bending. , 1 ’
character by being faied witpbamboo. Iy - Within the culm walls the strong; hard
- It is my expectation that an architect : tis.sue.s~ of high tensile strength are most I
will pr,qsentlyeappear who combines a su- (‘. highly concentrated near the surface. In
0 thi; position they can function most effi-
62
.. ciently, both in giving ‘mechanical strength
/
’ y W. E. Cohen. Utilization of Bamboo and in forming a firm, ‘resistant shell, I
i 1
in.Japan, p. 1. Commonwealth of Australia, 3. The substance and grain.of barn- :
‘Scientific and Industrial Research Organi- boo, culms make them easy to divide by
zation. South.heiboufpe, Au.s$ra.lia. April hand”*into shorter pieces (by sawing or 1 1
l’cr47,. -. (by split- ’
- I
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s,?.I .
,,
&v,%;A*..i“,J. -i, I_ ., - - -1
9. & ting). No dostly.machines, only simple
.: . L
tools: are ,.required. ,, P attaohed to hardwoods,
.-‘-: 4’. .. The natural surface of most ba,m-‘,,O
I,:.$ ,, >
j. boos is clean, hard, and smooth, with an ‘*
,,I
I?. ,.
, attF&tive color when the culms are prop-
.; erlycmatured tin?d seasoned.
” 5. Bamboos have little*waste, and no : certain ciriumstahces,
1
.
,f bamboo posts ‘j
$nstead of a conventional foundation for . :
‘I : ‘low-co&f ‘houses may be seen in -both hem-!”
‘, ‘, ”
p: ,. ispheres’ (fig. 2). Wriless they are treated
‘with somkreffective fungicidal’preservative, - lection of materials for tl?e ’
of structural elements, the
: .,
,’ .; ” last more-than two or three years onythem
:,~, *
These tip cuts nlayF,e used in
,;’
mn/daioni and tye roof :
P. is-the’ part of ‘:.
10. I . *
* i’,
I’ )I
1/
Spacing specifitatidns must be worked out
In the Far East loc&lly for the bndividuaP species of bamboo ’
.
for lashings are commenly’ and the si’ze of culmQ&sed.
*
more rarely from rattan. The flodr *dovering may be made bf’small
bamboos’ yieid bT+ittle wh’ole culms, stri-ps , or bamboo boards made.
or the bark of’certain’ * by opening and flattening out-whole culms . _
be use’s for lashings. (figs. 8, 9, and lo).” When’the.floor’%onsists r :
iron wire, mmost’of it of-bamboo boards, jt is gengrally,fastened
down My the ube of thin strips of bamboo
empirical;kn&l- secured to the supporting members by
boo.craftsmen in variqus cdun’i thongs, w.ire jashings, or small nlils, accord- =
the ;most highly recommended l‘ng to local preference and the materials
selection and us’e of avail- available (fig. 6, B). c j
Howeyer, a resourceful per- 2
experience in building ma’y
Walls, Partitions ,,.‘2eilingZ
&uggest sound .and useful mod- The construction ,of bamboo wa.115 is’sub-
conventional procedures. ject to infinite variation, depending on*the
strength required.(for resistance to natural
‘forces such as hurricanes and earthquakes),
^ .)
the protection desired from rain and ordinary ,’
wind.s,/and the need ‘for light and ventilation.
Eithe ‘whole cu-lms or.longiLdinal halves j : ~
may 6’ e used, and they may be applied in #
i / .
eith.er horizontal or vertical array, They
‘function more effectively, however, when
walls ir;ade of conventional stone, rammed
earth, or adobe bricks.
: Another form of wall construction,‘per-
.haps more widely used, ;s known in Peru
11. 7 --‘.I--‘-
. .
1
are attached, they provide a suitable base If window openings are provided, they
may-be framed with b$mboo or%ood.
windows ace left unglazed and unscreened.
Closure m,a:r be provided i&the form of a ’
00 mattilg or palm-leaf thatch. Win-
ported by a light framework of bamboo. pales.
In the..Philippine Is la.nds , and .generally in
the Far East, where suitable bamboos are
plentiful, the partitions and even the outer generally considered unhealthful. Actually,
the closing of houses at night’is justifiable
on other, more realistic, ground: ‘it prevents
the entrance of mosquitoes, rats, bats, and
other unwelcome visitors. Permanent wind
Because of their high strength-weighf
ratio, bamboos are used to excellent advan-
tage for stru~tt~ral..eIenients in roof con-
struction (fig. 6, A). In designingthe r&$;
<account must be taken of the nature -and ’
‘weight of the roof coverming to (be used, ‘<.
whether it be grass or palmleaf-thatch,
halved bamboo culms (fig: lq), bamboo..
split from larger culms. Bamboo matting
kitchen fife.
Edward Beckwith’s photograph’of.the ’ ,,
Q-in-central Cele,bes (see ,-:: - ’
frontispiece) IS another striking illustra-‘ j
tion of.the,use ‘of bamboo in roof architec- ’
ourou, Pierre. &es’ Paysans du
Delta Tonkinois .. Publ’ica’tions de 1’Ecole ’
airchild, The World Grows
12. *Pipes and Troughs (fig, 19). In Japan, closed’-pipe water.sys-
.*
The culms of certain bamboos, w-ith terns are ‘constructed of bamboo but it is
diaphragms removed,” serve admirably very difficult to make the joints leakproof,
ition+of pipes and tro hs. Underground drainage may’be effected
halves of bamboo ‘cu’ms
Y by means of bamboo pipes of simple con- -
0
very satisfactory eave troughs. Where structron. T.he steps in preparing the bam-
boo for such.use,,ar!k. (1) halving the culms, i
(2) removing th&d&p”hragms from one half
a barrel- 6r cistern for to-make the lower..‘section of the drain pipe,
Where rainfall is heavy-, they-are (3) cutting notches in the edge of the other
the ‘water from the roof to, half to permit the free entrance of water, *
in order to ‘avoid excessive (4) treating the two halves with preser’va-
tive (5- to lo-percent pentachlorophenol
*in light oil), (5) placing them together again .
in their original relation, and (6) binding ‘.
them together with wire: S’ch drains may
be .extended to ,any length by lacing the
L
smaller tip end of one pipe &to the larger
basal end of the succeeding onerr,
To be suited for the uses just &scribed, -
the bamboo culms should have a dia&e-$,er ..,
with the,diaphr!rgms *removed make suitabl;.‘ large enough‘to give therequired carry&g ( ‘_
.-.
I:$:.: .:: .Lcohduits for bringing whter for domeT$e use ccipacity, and the walls should be thick eno&&, ’ ’
-fyy’t_s_l. sour cq i to tile hou~~-b~‘&v~<y~ to prevent collapse under use.
:f$“+~‘.. . ---=--- v
‘Ii:;... ., ; j- 1,
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13. Bamboo Reinfoxement df Concrete
I. _ . Published references to the use of bam- readily available information on the subject
boo in reinforcing cement concrete strut- is to be found in the report of a serie’s of
,- . ,>,.-tures or parts thereof indicate that the prac- experiments carried out by and under the’
tice has been followed to some extent locally, di’rection of Profes,sor H. E. Glenn: Two
!. for some d.ecadkat least, in the’Far East - important sections of this report are quoted -
j (China, Japan,, and the Philippine Islands). here,‘in entirety:?/
,. * During the 1930’s several, experiments were
. /: carrPed.out in Europe, pariicularly in Ger- q H. E. Glenn. Bamboo Reinforcement
7: ,:
,- many and Italykto,test the ‘performance of ’ of Portland Cement Concrete Structures,
- - cement concrete beams reinforced with bam- pp. 123-127. Clemson College Engineering
: I. boo.;‘-‘: ’ .- - Experiment Station. Bul.’ 4. Clemson, S. C.
0
: ’ The most recent. comprehensive, and May 1950.
,: ,.
I;// .
I’ .,;/A ,,l <
.:- ‘. .- .
‘; ” ._ I
i Summary of Conclusions ‘
,i i
I Fr,oni Results of Tests. on
,r
7 ‘,
-._ ,,, , Bamboo Reinforced Concrete Beams 2!,
:.I ,
‘,.
I. .* Below is given’s sum me-+nLthe conclusions as indicated from the
.:,. : _..
..,: ,’ results,of‘tests on the various beams included in this study. +
;--. P’ 1. Bamboo r,einforcement’iikdncrete beams-does not prevent the
* ._
‘. failure of txe’concrkte by crao,king at loads materially,%n excess of 1
,. -.
those. to be excected fr&n:an unreinforced member having the same
*I. ‘3.
d&e& ions, ,Tz*’ .:c ,,
2’ ,t ‘S<
“ 2. Bamboo reinforcement in concrete beams does increase the
:’ load ca&ify of the m,ember at ultimate dailure considerably above that
: .-- ,. _ -,A
to be ekpected from an unreinforced member having ti,e same dimensions. /
.C’ ..
. 3. =I’& load capadity.oh’ba&boo reinforced concrete bgams increased 3 /-
‘,, .- . I’ . /-
“b ,, ’ I: with increasingper’centages’ of the bamboo reinforcement up to an opti- .
.i.
mum valae; I
,i I
,I 4,) ‘This opt&urn ;alue -occurs when Yhe’cross-sectiona! area of the
: IS
I., --~ -ldngitudinal bamboo-_ reixifoicement,
-.. was from three to four percent of !!
-II _,
‘.S ,
%mcross-Laectional’area OX the concrete jn the member.
--&-.
j fl, ,’ -. r’,r,‘ze-: $. The load required td cause the failure of concrete beams rein-’ ~1/
> ‘3,
r forced with bamboo was from four to.fiv,e times greater than that. re-
,.‘Y ‘“%
’ quired for concrete,members hav-$rg’equal dimensions and.wkhno re----.- mm--m-;---. ~- 7.
/, .. . : I
inforcement. ,.
.7: .; 6. Concrete beams with fongitudinal ba.mboo reinforc;ment may be :’ ..’
:,. <_, 4 :I
.; , .,.A I afely loads from two to three times greater than
‘.. . :
a.c -. concrete members having the same dimensions and T j
_’ b u
‘i’- ,( 4 I
;
.<’I ,,; i % -
&rns reinforced .with.unseasoned bamboo show .’ ’ .
.
-. . d capacities than do equal sections reinforced with !
‘%
_” ,‘, 0. ,,Z’ a_ bamboo. This statement w>as valid so long as’ the i
.’.., 1% 8 ‘-
-. %,’ o had not dried out andseasoned while encased in thg II
/’
. , /, / ;: ::
concrete’when the load was apbljed: ,’
When unseasoned untreated bafnboo was used as ‘the longitudinal; ,’ ,’ 11,dL~ ,
(
thei,
14. _ : , ! _ -
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.( --
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- absorption of moisture from the wet concrete, andthis swelling-action
'$b -' :
often caused longitudinal cracks in the iconcrete, thereby lowering the
load capaiity ofthe~members. These SW& cracks were more likely to
I ” . occur in members, where the percentage of bamboo reinforcement was
-/
high. This ter$ency was lessened by the use of hjgh early strength con-
‘! ,, ,y’<;, 3. ; * *
.drete.
‘i :
The load,‘capacities of concrete members reinforced with barn- ’
3.
, boo vary with the dimensions of the members.
& *
: 2 10. The unit stress in the longitudinal bamboo reinforcem,ent in
concrete $rnembers decreased with increasing percentages of reinforce-
-3 -__... -* ~. ~ment.
11. The ultimate tensile strength of the bamboo in bamboo r-einforced
‘;
i ooricrete members was not affected by changes ip the cross-sectional-
. ..
” area of the members so long as the ratio of bre3dth to depth was con-
/- stant’but was ‘dependent upon the ‘amount of bamboo used for reinforce-
. -. .a.- ment. *,$8 . D
.J;‘, , 3
4,-i. . jsj&g _,.. . ,l.&’ Members having the percentage of bamboo reinfbrce- >”
___I.- -; __.- tment(bet&.en three and four are capable of producing tensile
r _-----’ .,
-. stresses in the.bamboo,of from 8:OOO to 10,000 pounds per square inch.
13. In designing concrete members reinforced with bamboo, a safe
tensile stress for the bamboo of from 5,000 to 6,000 pounds per square’ j I
._ ---. ,
2 .inch may: be used.
14. concrete members reinforced. with seasoned bamboo treated
with a brush coat of asphalt emulsion developed greater load capacities ,’
;i’
1 than did equal sections in which the bamboo reinforcement was seasoned ’ i
.’
untreated a,r unseasoned bamboo. I/
/ 15; When soaspned bamboo treated with a brush coat of asljhalt _
emulT$on was useil,‘as the longitudinal reinforcement in concrete mem- -
bers,/there was some tendency for.the concrete to develop-swell cracks; * .,‘:
i I -.
.: _ ‘especially when t,he per,centage of bamboo reinforce’ment was high,
2” ,,E . 16. Care should be exercised when using asphalt emulsion as a
waterproofing agent on seasoned bamboo as an excess of theemulsion
x 1i
on the outer’perimeter of the cul’m might act as a lubricant to materi-
L, /,i
-‘. ., ally lessen the bond between the concrete and bamboo. 1
.. -- - :
1,,, / l?. Concrete members reinforced with unseasoned sections of barn- I
.,i’ ; ‘h
!> - b/oo culms, which had been split along their horizontal axes, appeared
i .--?~, ;i , ,’ $o develop great$r’loa,d capacities than. did equal sections iii which the > .
, i
a -5 - P. ‘-. .,reinforcement consisted of.unsea’soned whole.culms.
.,.! 18. Concrete members reinforced with seasoned sections of bam-
n:-,
._. ,_ /boo culms,;‘whi,ch had beeri‘split along their 1. : t
1. with a brudh’coat of asphalt
2 !. -8
1 load cap’acities than did/equal sections in whish the . -*
1I
: I split sey’tions !of seasoned J.. ‘:
.
.m > 19; When, split’sect&ns.
1_
.I ‘. .,,, were,used as/the reinforcement_iii-& concrete beam, ‘longitudinal cracks,
, ,:
apeeared in-the conc$ete due ‘b the swelling action of the bamboo.
: it
cracking-of t,hem,cozcrete was pf~s-ufficient.Yinten,sityias. to virtually
‘. the load capacitie’s of the members. . -
‘- ._ ~~.-,~ , i
c <O. 3~ When unseasoned bamboo was used as the reinfo>cqment in a 11;
. ,;’ : :‘.
_-’ .7 concrete member, the bam,boo sdason;ed and shrank over’s peri,od of %
..- time while encased in the c0ncr.et.e. This seasoning action of the bam-
boo materially lowere’d the effective bond between’the bamboo’and con-
L’ Crete with’s resultantle
i o :
,. ..s-- 21. Increasing the
- <; ,:
_..
‘_
z.’ ,, .
_'
; .
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15. reed with se,asoned bamboo treated /.
with me-thylolurea’did not develop greater .loa.d capacities’than did eq&l
sections in which the bambob reinforcqment yas seasoned culms tre
pith a-brush coat oj E asphalt emulsion. ~-~ . *L. ^ ,
23.. The load ca Lpacities;i”dr concrete members reinforced with n-
seasoned, seasox&d ‘or zia%oned and treated bamboo culms, were iB-
.,.
creased by using split bamboo dowels as-the diagonal tension rein rce-
ment along the sections of the beams where the .v.ertical shear wa high.
24. The load capacitifs for concrete memb&rs reinforced wi un-
i
seasoned, seasoned or seasoned and treated split sections of bamboo
.1,.
“I
wereGreased by-the use, of.a combination .of split dowels and the bend-
ing up ‘of the upper
beam
ticdl
rows of the split
into the ton and covering-ihm~eXioncof3he
shear was high:
bamboo -from the bottom
beams
b
of hhe
tiherelthe
,
ver- m.
._ : c j n
: 25. Ultimate failure of bamboo reinforced concrete memb, i rs usu-
. I
arlly was ‘caused by diagonal tension failures even though diagonal ten-
sion reinforcement was provided. ‘_ m *
c
T ‘ 4
-; . ” 26. A study of the deflection data for all ?he heam specimens tes@d
vi , indicated; .
; -it,,
: (a). Thit’thedefleition-s of the beams when tested follo&ed a fairly
:, , ,, ’ accurate straight l@e variation until the appearance of the first
i.,.-... -- , n
, ‘ ,~ in. the concrete.
1;
,:(-_ (b).‘Immed,iately follov;~~~igah~.~_first cr.ack, there wasp pronounced :..
flattening of the deflection curve (probably due to local bond slippage)
.’ follow’ed, by another’period of fairly accuratestraight line variation, but
at a lesser slop$, until ultimate f$lure of the memb;~Sr occurred. This
flattening of the deflection curve was more pronouncWlGn,the members
‘ where the amount of lo$itudinal bamboo reinforcei-nent was--s,mall.
‘..- ?T- .(c)‘ In all’cases’notpd-, the deflection curve h,ad,a-lesser-,slope,after..
. :the appearance of the first, crack in thg concrete, even though Kigli per-,
----_--- --___.-- __..~_
pronounced,vcriations wereobserved when the beh$l&r of ‘A.
bamboo’reinforced concrete member: under flexure and hav&g “‘tee” 1 _ ..‘. I.:
area%jth that of equal members having rectangular .:I. L- A .,,
‘
.~ ._.__.
in*cLrrPd-concrete members tinder flexure and con-
--.----
sisiing of “tee”,.sections~ wer,e no more effect-i$e than were equal zec- L:
tangular sections,, provided the breadth of-the ~~e’rn. of’the ‘teeri sect,iqn _’
waL.equal, to that of the rec’ta%gular.‘sec,tion.:and the effective .depth of’ ,
.,i; ‘,
..*: *,1 ,, :
F .: Dision and Con&ruction Principl& _ . ..- ...I._...-+ .,---. -.
Recommended for Bamboo Reinforced Concrete, ~
_ In .i mi aortant concrete members, tl& use. of whole culms of I-
.* mended Bs the r,einforcing .nia?e.r$,l; ' f I!
InFrete slab?’ ,&id seconda* members, green,*@qeasoned, &hole ! I+
The c~&+ 30~riot
&fou!thT;of I.,.. a&rich.
1 -A ’ WEen~pos&ible, the bjamboo*us.eii as ‘,
&‘in,.c$&&ete members, ‘subje.ct;t~flexur’~, should be cut 4~
m three weeks to on& month before __ $5
+--==--. -- ).- ) 1 ,, _ ,
.--5. -.’ ”
.- ,’
renounced browri m’ -x
