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Use o! REC'CLED AGGREGATES In CONCRETE( A Pa%a#i")S*i!$

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)ne of the "a*or challen es of our present societ( is the protection of en$iron"ent. So"e of the

i"portant ele"ents in this respect are the reduction of the consu"ption of ener ( and natural ra%

"aterials and consu"ption of %aste "aterials. These topics are ettin considerable attention under

sustainable de$elop"ent no%ada(s. The use of rec(cled a re ates fro" construction and de"olition

%astes is sho%in prospecti$e application in construction as alternati$e to pri"ar( 4natural5

a re ates. It conser$es natural resources and reduces the space re1uired for the landfill disposal.

This paper presents the e+peri"ental results of rec(cled coarse a re ate concrete and results are

co"pared %ith the natural crushed a re ate concrete. The fine a re ate used in the concrete6 i.e.

rec(cled and con$entional is 788 percent natural. The rec(cled a re ate are collected fro" foursources all de"olished structures. or both t(pes of concrete i.e. M9:8 and M9:;6 %!c ratio6 "a+i"u"

si-e of a re ate and "i+ proportion are kept constant.

The de$elop"ent of co"pressi$e stren th of rec(cled a re ate concrete at the a e of 76<6=67>6:?6

;@6 and 8 da(s the de$elop"ent of tensile & fle+ural stren th at the a e of 76<6=67> and static

"odulus of elasticit( at the a e of :? da(s are in$esti ated. The results sho%s the co"pressi$e6

tensile and fle+ural stren ths of rec(cled a re ate are on a$era e ?; to ; of the natural

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a re ate concrete. The durabilit( para"eters are also in$esti ated for rec(cled a re ate concrete

and are found to be in ood a ree"ent %ith BIS specifications.

In$%o# c$ion

An( construction acti$it( re1uires se$eral "aterials such as concrete6 steel6 brick6 stone6 lass6 cla(6

"ud6 %ood6 and so on. 0o%e$er6 the ce"ent concrete re"ains the "ain construction "aterial used in

construction industries. or its suitabilit( and adaptabilit( %ith respect to the chan in en$iron"ent6

the concrete "ust be such that it can conser$e resources6 protect the en$iron"ent6 econo"i-e and

lead to proper utili-ation of ener (. To achie$e this6 "a*or e"phasis "ust be laid on the use of %astes

and b(products in ce"ent and concrete used for ne% constructions. The utili-ation of rec(cled

a re ate is particularl( $er( pro"isin as =; per cent of concrete is "ade of a re ates. In that

case6 the a re ates considered are sla 6 po%er plant %astes6 rec(cled concrete6 "inin and

1uarr(in %astes6 %aste lass6 incinerator residue6 red "ud6 burnt cla(6 sa%dust6 co"bustor ash and

foundr( sand. The enor"ous 1uantities of de"olished concrete are a$ailable at $arious construction

sites6 %hich are no% posin a serious proble" of disposal in urban areas. This can easil( be rec(cled

as a re ate and used in concrete. Research & ,e$elop"ent acti$ities ha$e been taken up all o$er the%orld for pro$in its feasibilit(6 econo"ic $iabilit( and cost effecti$eness.

An in$esti ation conducted b( the en$iron"ental resources ltd. 47 = 5 for 'uropean 'n$iron"ental

co""ission 4''C5 en$isa es that there %ill be enor"ous increase in the a$ailable 1uantities of construction and de"olition concrete %aste fro" ;; "illion tons in 7 ?8 to <8: "illion tons b( the

(ear :8:8 in the ''C "e"ber countries. As a %hole6 the safet( and en$iron"ent re ulations are

beco"in strin ent6 de"and for i"pro$e"ent in techni1ues & efficienc( of the past de"olition

"ethods is ettin pronounced. Special rules and re ulations concernin the de"olition ha$e alread(

been introduced in se$eral countries like 2./.6 0olland and Dapan.

The "ain reasons for increase of $olu"e of de"olition concrete ! "asonr( %aste are as follo%sE9

i. Man( old buildin s6 concrete pa$e"ents6 brid es and other structures ha$e o$erco"e their

a e and li"it of use due to structural deterioration be(ond repairs and need to be de"olished

ii. The structures6 e$en ade1uate to use are under de"olition because the( are not ser$in the

needs in present scenario

iii. Ne% construction for better econo"ic ro%th

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i$. Structures are turned into debris resultin fro" natural disasters like earth1uake6 c(clone and

floods etc.

$. Creation of buildin %aste resultin fro" "an"ade disaster!%ar.

In stud( conducted b( authors for RCC buildin s6 the appro+i"ate percenta e of $arious construction"aterials in de"olition %aste is presented in i . 7. This "a( $ar( dependin upon the t(pe of

structure.

In "an( densel( populated countries of 'urope6 %here disposal of debris proble" is beco"in "ore

and "ore difficult6 the rec(clin of de"olition %aste has alread( been started. As per the sur$e(

conducted b( 'uropean ,e"olition Association 4',A5 in 7 :6 the se$eral rec(clin plants %ere

operational in 'uropean countries such as @8 in Bel iu"6 ;8 in rance6 =8 in the Netherlands6 7:8 in

2nited /in do"6 ::8 in Ger"an(6 :8 in ,en"ark and >< in Ital(. The rec(clin of construction &

de"olition %aste beco"es eas( & econo"ical6 %here$er co"bined pro*ect in$ol$in de"olition and

ne% construction are taken up si"ultaneousl(. The possible uses of construction and de"olition

%astes are i$en in Table 7.

Rec6clin" an# Re se o! Cons$% c$ion 3 De)oli$ion Was$es in Conc%e$e

The rec(clin and reuse of construction & de"olition %astes see"s feasible solution in rehabilitation

and ne% constructions after the natural disaster or de"olition of old structures. This beco"es $er(

i"portant especiall( for those countries %here national and local policies are strin ent for disposal of

construction and de"olition %astes %ith uidance6 penalties6 le$ies etc. A t(pical la( out plan of

rec(clin plant for construction %aste has been sho%n in i ure. :. The properties of rec(cled

a re ate concrete obtained b( $arious authors are i$en in Table:.

In$e%na$ional S$a$ s

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The e+tensi$e research on rec(cled concrete a re ate and rec(cled a re ate concrete 4RAC5 as

started fro" (ear 7 >; in $arious part of the %orld after second %orld %ar6 but in a fra "ented

"anner. irst effort has been "ade b( Ni+on in 7 == %ho co"plied all the %ork on rec(cled a re ate

carried out bet%een 7 >;97 == and prepared a state9of9the9art report on it for RI 'M technical

co""ittee <=9,RC. Ni+on concluded that a nu"ber of researchers ha$e e+a"ined the basic properties

of concrete in %hich the a re ate is the product of crushin another concrete6 %here other

concentrated on old laborator( speci"ens. 0o%e$er6 a co"prehensi$e state9of9the9artdocu"ent on the

rec(cled a re ate concrete has been presented b( 0ansen & others in 7 : in %hich detailed

anal(sis of data has been "ade6 leadin to%ards preparation of uidelines for production and

utili-ation of rec(cled a re ate concrete.

It has been esti"ated that appro+i"atel( 7?8 "illion tones of construction & de"olition %aste are

produced each (ear in 'uropean 2nion. In eneral6 in '26 ;88 / of construction rubble and

de"olition %aste correspond annuall( to each citi-en. Indicati$el( 78 of used a re ates in 2/ are

RCA6 %hereas =?6888 tons of RCA %ere used in 0olland in 7 >. The Netherland produces about

7>"illion tons of buildin s and de"olition %astes per annu" in %hich about ? "illion tons are rec(cled

"ainl( for unbound road base courses.

The :?; "illion tons of per annu" construction %aste produced in Ger"an(6 out of %hich == "illion

tons are de"olition %aste. Appro+i"atel( =8 of it is rec(cled and reused in ne% construction %ork.

It has been esti"ated that appro+i"atel( 7< "illion tons of concrete is de"olished in rance e$er(

(ear %hereas in Dapan total 1uantit( of concrete debris is in the tune of 7897; "illion tons each (ear.

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The 0on /on enerates about :8 "illion tons de"olition debris per (ear and facin serious proble"

for its disposal.

2SA is utili-in appro+i"atel( :.= billion tons of a re ate annuall( out of %hich <89>8 are used in

road %orks and balance in structural concrete %ork. A recent report of ederal 0i h%a(s

Ad"inistration6 2SA refers to the relati$e e+perience fro" 'uropean data on the sub*ect of concreteand asphalt pa$e"ent rec(clin as i$en in Table <.The rapid de$elop"ent in research on the use of

RCA for the production of ne% concrete has also led to the production of concrete of hi h

stren th!perfor"ance.

In#ian S$a$ s

There is se$ere shorta e of infrastructural facilities like houses6 hospitals6 roads etc. in India and lar e

1uantities of construction "aterials for creatin these facilities are needed. The plannin Co""ission

allocated appro+i"atel( ;8 of capital outla( for infrastructure de$elop"ent in successi$e 78th &

77th fi$e (ear plans. Rapid infrastructural de$elop"ent such hi h%a(s6 airports etc. and ro%in

de"and for housin has led to scarcit( & rise in cost of construction "aterials. Most of %aste "aterialsproduced b( de"olished structures disposed off b( du"pin the" as land fill. ,u"pin of %astes on

land is causin shorta e of du"pin place in urban areas. Therefore6 it is necessar( to start rec(clin

and re9use of de"olition concrete %aste to sa$e en$iron"ent6 cost and ener (.

Central #ollution Control Board has esti"ated current 1uantu" of solid %aste eneration in India to

the tune of >? "illion tons per annu" out of %hich6 %aste fro" construction industr( onl( accounts for

"ore than :; . Mana e"ent of such hi h 1uantu" of %aste puts enor"ous pressure on solid %aste

"ana e"ent s(ste".

In $ie% of si nificant role of rec(cled construction "aterial and technolo ( in the de$elop"ent of urban infrastructure6 TI AC has conducted a techno9"arket sur$e( on F2tili-ation of Waste fro"

Construction Industr(F tar etin housin !buildin and road se "ent. The total 1uantu" of %aste fro"

construction industr( is esti"ated to be 7: to 7>.= "illion tons per annu" out of %hich =9? "illion

tons are concrete and brick %aste. Accordin to findin s of sur$e(6 =8 of the respondent ha$e i$en

the reason for not adoptin rec(clin of %aste fro" Construction Industr( is Not a%are of the

rec(clin techni1ues %hile re"ainin <8 ha$e indicated that the( are not e$en a%are of rec(clin

possibilities. urther6 the user a encies! industries pointed out that presentl(6 the BIS and other codal

pro$isions do not pro$ide the specifications for use of rec(cled product in the construction acti$ities.

In $ie% of abo$e6 there is ur ent need to take follo%in "easuresE9

• Sensiti-ation! disse"ination! capacit( buildin to%ards utili-ation of construction & de"olition

%aste.

• #reparation and i"ple"entation of techno9le al re i"e includin le islations6 uidance6

penalties etc. for disposal of buildin & construction %aste.

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• ,elineation of du"pin areas for pre9selection6 treat"ent6 transport of RCA.

• National le$el support on research studies on RCA.

• #reparation of techno9financial re i"e6 financial support for introducin RCA in construction

includin assistance in transportation6 establishin rec(clin plant etc.

• #reparation of data base on utili-ation of RCA.

• or"ulation of uidelines6 specifications and codal pro$isions.

• #reparation of list of e+perts a$ailable in this field %ho can pro$ide kno%ho% and technolo (

on totalit( basis.

• Incenti$es on usin rec(cled a re ate concrete9subsid( or ta+ e+e"ptions.

Realisin the future & national i"portance of rec(cled a re ate concrete in construction6 S'RC6

Gha-iabad had taken up a pilot R&, pro*ect on Rec(clin and Reuse of ,e"olition and Construction

Wastes in Concrete for o% Rise and o% Cost Buildin s in "id nineties %ith the ai" of de$elopin

techni1ues! "ethodolo ies for use rec(cled a re ate concrete in construction. The e+peri"ental

in$esti ations %ere carried out in Mat Science laborator( and Institutes around ,elhi!GB, to e$aluate

the "echanical properties and durabilit( para"eters of rec(cled a re ate concrete "ade %ith

rec(cled coarse a re ate collected fro" different sources. Also6 the suitabilit( in construction of

buildin s has been studied.

The properties of RAC has been established and de"onstrated throu h se$eral e+peri"ental and field

pro*ects successfull(. It has been concluded that RCA can be readil( used in construction of lo% rise

buildin s6 concrete pa$in blocks & tiles6 floorin 6 retainin %alls6 approach lanes6 se%era e

structures6 subbase course of pa$e"ent6 draina e la(er in hi h%a(s6 dr( lean concrete4, C5 etc. in

Indian scenario. 2se of RCA %ill further ensure the sustainable de$elop"ent of societ( %ith sa$in s in

natural resources6 "aterials and ener (.

E78e%i)en$al In.es$i"a$ions

In the present paper6 an endea$or is "ade so as to co"pare so"e of the "echanical properties of

rec(cled a re ate concrete 4RAC5 %ith the natural a re ate concrete 4NAC5. Since the enor"ous

1uantit( of concrete is a$ailable for rec(clin fro" de"olished concrete structures6 field de"olished

concrete is used in the present stud( to produce the rec(cled a re ates. The concrete debris %ere

collected fro" different 4four5 sources %ith the a e ran in fro" : to >8 (ears old and broken into the

pieces of appro+i"atel( ?8 "" si-e %ith the help of ha""er & drillin "achine. The forei n "atters

%ere sorted out fro" the pieces. urther6 those pieces %ere crushed in a lab *a% crusher and

"echanicall( sie$ed throu h sie$e of >.=; "" to re"o$e the finer particles. The rec(cled coarse

a re ates %ere %ashed to re"o$e dirt6 dust etc. and collected for use in concrete "i+. The fine

a re ate %ere separated out6 and used for "asonr( "ortar & lean concrete "i+es6 %hich is not part

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this reported stud(. But these %ere found to suit for nor"al brick "asonar( "ortar and had nor"al

settin and enou h stren th for "asonar( %ork.

Conc%e$e Mi7es

The t%o different "i+ proportions of characteristic stren th of :8 N! "": 4M :85 and :; N!"": 4M

:;5 co""onl( used in construction of lo% rise buildin s are obtained as per IS 78:@: H 7 ?: or both

rec(cled a re ate concrete and natural a re ate concrete. ,ue to the hi her %ater absorption

capacit( of RCA as co"pared to natural a re ate6 both the a re ates are "aintained at saturated

surface dr( 4SS,5 conditions before "i+in operations. The proportions of the in redients constitutin

the concrete "i+es are 7E7.;E:. and 7E7.:E:.> %ith %ater ce"ent ratio 8.;8 & 8.>; respecti$el( for

M9:8 & M9:; rade concrete. The ordinar( #ortland ce"ent of >< rade and natural fine a re ates

40ald%ani sand5 are used throu hout the castin %ork. The "a+i"u" si-e of coarse a re ate used

%as :8 "" in both rec(cled and natural a re ate concrete.

The total t%o "i+es %ere cast usin natural a re ate and ei ht "i+es %ere cast usin four t(pe of

rec(cled a re ate concrete for M9:8 & M9:;. The de$elop"ent of co"pressi$e stren th is "onitoredb( testin the 7;89"" cubes at 76 <6 =6 7>6 :?6 ;@ and 8 da(s. In one set < cubes %ere cast for

each "i+. The c(linder stren th and correspondin strain & "odulus of elasticit( %ere "easured in

standard c(linder of 7;8+<88 "" si-e at the a e of :? da(s. The pris" of si-e 7;8+7;8+=88 "" and

c(linder of si-e 7;8+<88"" %ere cast fro" the sa"e batches to "easure le+ural stren th and

splittin tensile stren th respecti$el(. This paper reports the results of e+peri"ental in$esti ations on

rec(cled a re ate concrete.

P%o8e%$ies o! Rec6cle# Conc%e$e A""%e"a$e

Pa%$icle Si4e Dis$%i5 $ion

The result of sie$e anal(sis carried out as per IS :<?@ for different t(pes of crushed rec(cled concrete

a re ate and natural a re ates. It is found that rec(cled coarse a re ate are reduced to $arious

si-es durin the process of crushin and sie$in 4b( a sie$e of >.=;""56 %hich i$es best particle si-e

distribution. The a"ount of fine particles 4 >.=;""5 after rec(clin of de"olished %ere in the order

of ;9:8 dependin upon the ori inal rade of de"olished concrete. The best 1ualit( natural

a re ate can obtained b( pri"ar(6 secondar( & tertiar( crushin %hereas the sa"e can be obtained

after pri"ar( & secondar( crushin incase of rec(cled a re ate. The sin le crushin process is also

effecti$e in the case of rec(cled a re ate.

The particle shape anal(sis of rec(cled a re ate indicates si"ilar particle shape of natural a re ateobtained fro" crushed rock. The rec(cled a re ate enerall( "eets all the standard re1uire"ents of

a re ate used in concrete.

S8eci!ic G%a.i$6 an# Wa$e% A5so%8$ion

The specific ra$it( 4saturated surface dr( condition5 of rec(cled concrete a re ate %as found fro"

:.<; to :.;? %hich are lo%er as co"pared to natural a re ates. Since the RCA fro" de"olished

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concrete consist of crushed stone a re ate %ith old "ortar adherin to it6 the %ater absorption

ran es fro" <.8; to =.>8 6 %hich is relati$el( hi her than that of the natural a re ates. The Table

> i$es the details of properties of RCA & natural a re ates. In eneral6 as the %ater absorption

characteristics of rec(cled a re ates are hi her6 it is ad$isable to "aintain saturated surface dr(

4SS,5 conditions of a re ate before start of the "i+in operations.

B l Densi$6

The rodded & loose bulk densit( of rec(cled a re ate is lo%er than that of natural a re ate e+cept

rec(cled a re ate9RCA>6 %hich is obtained fro" de"olished ne%l( constructed cul$ert. Rec(cled

a re ate had passed throu h the sie$e of >.=;"" due to %hich $oids increased in rodded condition.

The lo%er $alue of loose bulk densit( of rec(cled a re ate "a( be attributed to its hi her porosit(

than that of natural a re ate.

C% s*in" an# I)8ac$ Val es

The rec(cled a re ate is relati$el( %eaker than the natural a re ate a ainst "echanical actions. As

per IS :<?@6 the crushin and i"pact $alues for concrete %earin surfaces should not e+ceed >;

and ;8 respecti$el(. The crushin & i"pact $alues of rec(cled a re ate satisf( the BIS

specifications e+cept RCA: t(pe of rec(cled a re ate for i"pact $alue as ori inall( it is lo% rade

rubbles.

Co)8%essi.e S$%en"$*

The a$era e co"pressi$e stren ths cubes cast are deter"ined as per IS ;7@ usin RCA and natural

a re ate at the a e 76 <6 =6 7>6 :?6 ;@ and 8 da(s and reported in Table ;. The table > sho%s that

the tar et cube stren th %as achie$ed at :? da(s for all t(pes of concrete. As e+pected6 the

co"pressi$e stren th of RAC is lo%er than the con$entional concrete "ade fro" si"ilar "i+proportions. The reduction in stren th of RAC as co"pare to NAC is in order of :9 7> and =.; to

7@ for M9:8 & M9:; concretes respecti$el(. The a"ount of reduction in stren th depends on

para"eters such as rade of de"olished concrete6 replace"ent ratio6 %!c ratio6 processin of rec(cled

a re ate etc.

S8li$$in" Tensile 3 Fle7 %al S$%en"$*

The a$era e splittin tensile and fle+ural of rec(cled a re ate are deter"ined at the a e 76 <6 =6 7>6

& :? da(s $aries fro" 8.<8 9<.7 M#a and 8. ;9 =.: M#a respecti$el(. The reduction in splittin and

fle+ural stren th of RAC as co"pared to NAC is in order of ;97: and > 97; respecti$el(.

Mo# l s o! Elas$ici$6

The static "odulus of elasticit( of RAC has been reported in Table > and found lo%er than the AC. The

reduction is up to 7; .The reason for the lo%er static "odulus of elasticit( of RCA is hi her

proportion of hardened ce"ent paste. It is %ell establish that 'c depends on 'c $alue of coarse

a re ate6 %!c ratio & ce"ent paste etc. The "odulus of elasticit( is critical para"eter for desi nin

the structures6 hence "ore studies are needed.

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D %a5ili$6

The follo%in para"eters %ere studied to assess the influence of rec(cled a re ates on durabilit( of

concreteE

Ca%5ona$ion

F%ee4e(T*a2 Resis$ance

Ca%5ona$ion

C) : fro" the air penetrates into the concrete b( diffusion process. The pores 4pore si-eJ788n"5 in

the concrete in %hich this transport process can take place are therefore particularl( crucial for the

rate of carbonation. The carbonation tests %ere carried out for 8 da(s on the speci"ens

47;8+7;8+7;8""5 of rec(cled a re ate concrete and natural a re ate concrete in carbonation

cha"ber %ith relati$e hu"idit( of =8 and :8 C) : concentration. The carbonation depths of

rec(cled a re ate concretes for different rade %ere found fro" 77.; to 7>"" as co"pared to

77"" depth for natural a re ate concrete. This increase in the carbonation depth of RAC as

co"pared to NAC6 attributed to porous rec(cled a re ate due to presence of old "ortar attached to

the crushed stone a re ate.

F%ee4e(T*a2 Resis$ance

In the free-e9tha% resistance test 4cube "ethod56 loss of "ass of the concrete "ade %ith rec(cled

a re ate %as found so"eti"es abo$e and belo% than that of concrete "ade %ith natural a re ate.

The results %ere so close that no difference in free-e tha% resistance 4after 788 c(cles5 could be

found. The literature also found that the effect of ce"ent "ortar adherin to the ori inal a re ate in

RAC "a( not ad$ersel( affect the properties of RAC.

O5s$acles in Use o! RCA 3 RAC

The acceptabilit( of rec(cled a re ate is i"peded for structural applications due to the technicalproble"s associated %ith it such as %eak interfacial transition -ones bet%een ce"ent paste and

a re ate6 porosit( and trans$erse cracks %ithin de"olished concrete6 hi h le$el of sulphate and

chloride contents6 i"purit(6 ce"ent re"ains6 poor radin 6 and lar e $ariation in 1ualit(.

Althou h6 it is en$iron"entall( & econo"icall( beneficial to use RCA in construction6 ho%e$er the

current le islation and e+perience are not ade1uate to support and encoura e rec(clin of construction

& de"olished %aste in India. ack of a%areness6 uidelines6 specifications6 standards6 data base of

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utili-ation of RCA in concrete and lack of confidence in en ineers6 researchers and user a encies is

"a*or cause for poor utili-ation of RCA in construction. If the Go$t %ishes these obstacles can easil(

be re"o$ed.

Concl sion

Rec(clin and reuse of buildin %astes ha$e been found to be an appropriate solution to the proble"s

of du"pin hundred of thousands tons of debris acco"panied %ith shorta e of natural a re ates.

The use of rec(cled a re ates in concrete pro$e to be a $aluable buildin "aterials in technical6

en$iron"ent and econo"ical respect

Rec(cled a re ate posses relati$el( lo%er bulk densit(6 crushin and i"pact $alues and hi her %aterabsorption as co"pared to natural a re ate. The co"pressi$e stren th of rec(cled a re ate

concrete is relati$el( lo%er up to 7; than natural a re ate concrete. The $ariation also depends on

the ori inal concrete fro" %hich the a re ates ha$e been obtained. The durabilit( para"eters

studied at S'RC4G5 confir"s suitabilit( of RCA & RAC in "akin durable concrete structures of

selected t(pes.

There are se$eral reliable applications for usin rec(cled coarse a re ate in construction. 0o%e$er6

"ore research and initiation of pilot pro*ect for application of RCA is needed for "odif(in our desi n

codes6 specifications and procedure for use of rec(cled a re ate concrete. The sub*ect of use of RCA

in construction %orks in India should be i$en i"petus6 because of bi infrastructural pro*ects are

bein co""issioned includin Co""on Wealth Ga"es in :878.

Re!e%ences

7. 0ansen6 T.C. 47 :56 Rec(clin of ,e"olished Concrete Masonr(6 Rile" Report No. @6 '& N

Spon6 ondon6 Great Britain6 pp. <7@.

:. )ikono"ou6N.,.4:88;5 Rec(cled Concrete A re ates6 Ce"ent & Concrete Co"posites6 3ol.

:=6 pp<7;9<7?.

<. Thielen6G.4:88>5 Concrete Technolo ( Reports :8879 :88<6 Ger"an Ce"ent WorksAssociation.

>. 2S ,eptt. of Transportation 4:8885 Rec(cled Materials in 'uropean 0i h%a(s 'n$iron"ent9

2ses6 Technolo ies and #olicies6 Int. Technolo ( '+chan e #ro ra""e.

;. Bio*en6D. 47 @5 Waste Materials and Alternati$e #roducts #roFs and ConFs Concrete for

'n$iron"ental enhanced and #rotection6 ' & N Spon6 pp. ;?=9; ?.

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@. Buchner6 S. and Scholten6 .D. 47 :5. ,e"olition and Construction ,ebris Rec(clin in

'urope6 'uropean ,e"olition Association 4',A5.

=. er uson6 D. /er"ode6 ).N. Nash6 C. . Sketch6 W.A.D. and 0u+ford6 R.#. 47 ;56 Mana in

and Mini"isin Construction Waste6 Institution of Ci$il 'n ineers6 Tho"as6 Telford

#ublications6 2./.6 pp. 79@8.

?. Gottfredsen6 .R. and Tho erson6 . 47 >56 Rec(clin of Concrete in A ressi$e 'n$iron"ent6

,e"olition and Reuse of Concrete and Masonr( Rile" #roceedin :<6 ' & N Spon6 pp. <8 9

<7=.

. 0ansen6 T.C. 47 ?@5 Rec(cled A re ate and Rec(cled A re ate Concrete6 Seocnd state of

Art Report6 ,e$elop"ent 7 >;H7 ?;6 Rile" TC9,RC6 Material & Structure6 3ol. 7 6 No. III.

pp. :879 :>?.

78. 0endricks6 Ch. . 47 @56 Rec(clin and Reuse as a Basis of Sustainable ,e$elop"ent in

Construction Industr(6 Concrete for 'n$iron"ent6 'nhance"ent and #rotection6 '& N Spon6

pp. ><9;>.

77. /ikuchi6 M. and Kasuna a6 A. 47 >56 The Total '$aluation of Rec(cled A re ate and

Rec(cled Concrete ,e"olition and Reuse of Concrete and Masonr(6 Rile" #roceedin s :<6

'& N Spon6 pp. <@=9<==.

7:. aurit-en6 './. 47 >56 Introduction6 ,isaster #lannin 6 Structural Assess"ent6 ,e"olition

and Rec(clin 6 Rile" Report No. 6 '& N Spon pp.7 H78.

7<. Mc au hliu6 D. 47 <56 A Re$ie% of the #rospect for Greater 2se of Rec(cled and Secondar(A re ate in Concrete6 Concrete6 The Concrete Societ( Dournal6 3ol. :=6 N). @6pp. 7@97?.

7>. Merlet6 D.,. and #i"ienta6 #. 47 >56 Mechanical and #h(sico9 Che"ical #roperties of Concrete

#roduced %ith Coarse and ine Rec(cled Concrete A re ates6 ,e"olition and Reuse of

Concrete and Masonr(6 Rile" #roceedin :<6 '& N Spon6 pp. <><9<;<.

7;. Nikon6 #.D. 47 ?@56 Rec(cled Concrete an A re ate for ConcreteHa Re$ie%6 Rile" TC9<=6

,RC6 Materials Structures6 3ol. 7 6 No. 777.

7@. #au%6 C.,. 47 >56 Reuse of Buildin Materials and ,isposal of Structural Waste Material6

,isaster #lannin 6 Structural Assess"ent6 ,e"olition and Rec(clin 6 Rile" Report 6 '& N

Spon6 pp. 7<<97; .

7=. RI 'M TC 7:7 ,RG Reco""endation 47 >56 Specification for Concrete %ith Rec(cled

A re ates6 Materials and Structure6 3o. :=6 No. 7=<6 pp. ;;=9 ;; .

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7?. Sin h6 S./.6 Shar"a6 #.C.6 and Na ra*6 N. 47 =56 State9of9Art Report on Rec(cled A re ate

Concrete6 S'RC Report6 Gha-iabad.

7 . Shar"a6 #.C.6 Sin h6 S./. and Na ra*6 N. 47 ?56 uture of Rec(cled A re ate Concrete in

India6 National Se"inar on Ne% Materials and Technolo ( in Buildin Industr(6 Dul( :>9:;6

3i (an Bha%an6Ne% ,elhi6 pp. I397 =9I39 :8;.

:8. Sin h6 S. /. and #. C. Shar"a 47 ?5 Rec(clin and Reuse of Buildin Waste in Constructions9

A Re$ie%6 All India Se"inar on Concrete for Infrastructural ,e$elop"ent6 Roorkee6 pp <7=9

<: .

:7. Ta$akoli6 M. and Soroushian6 #. 47 @56 Stren th of Rec(cled A re ate Concrete "ade usin

ield ,e"olished Concrete as A re ate6 ACI Materials Dournal6 3ol. <6 No.:6 pp.7?:97 8.

::. Ta$akoli6 M. and Soroushian6 #.47 @56 ,r(in Shrinka e Beha$ior of Rec(cled A re ate

Concrete6 Concrete International6 3ol. 7?6 No. 776 pp. ;?9@7.

:<. 3(ncke6 D. Rousseau6 '. 47 >56 Rec(clin and Construction and ,e"olition Waste in

Bel iu" E Actual Situation and uture '$aluation6 ,e"olition and Reuse of Concrete &

Masonr(6 Rile" #roceedin :<6 '& N Spon6 pp. ;=9 @ .

:>. Ko ishita6 . et al. 47 >56 Beha$ior of Reinforced Concrete Bea"s containin Rec(cled Coarse

A re ate ,e"olition and Reuse of Concrete & Masonr( Rile" #roceedin :<6 '& N Spon6 pp.

<<79<>:.

:;. Kan ani6 /.6 0isaka6 M. and /asai6 K. 47 >56 #h(sical #roperties of Rec(cled Concrete usin

Rec(cled Coarse A re ate "ade of Construction %ith inishin Mater>ials6 ,e"olition andReuse of Concrete & Masonr(6 Rile" #roceedin :<6 '& N Spon6 pp. <= 9< 8.

:@. Shar"a6 #.C.6 Na ra*6 N.47 56 Rec(cled A re ate Concrete and Its I"portance in Indian

Conditions H All India Se"inar on Indian Ce"ent Industries E Challen es and #rospects of

Ce"ent Chandrapur 4Maharashtra5

:=. Ra"a""urth(6 /. & Gu"aste6 /.S.47 ?56 #roperties of Rec(cled A re ate Concrete6

Indian Concrete Dournal6 pp. > 9;<.

:?. Rahal6 /. 4:88=5 Mechnical #roperties of Concrete %ith Rec(cled Coarse A re ate6 Buildin

& 'n$iron"ent63ol. >:6 pp >8=9>7;.

NBMCW )ctober :88=

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