Prevention of Frost Damage

8/11/2019 Prevention of Frost Damage

1/18

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Research and Development Laboratories

.,

of the

.,

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Portland Cement Association

RESEARCH DEPARTME~

Bulletin 148

,

Prevention of rost amage

,

.. .

to Green concrete, : ~~

,., ., ,

..,

.,

,..

.

::

By

T. C. Powers

.,

1

,.

,,

,

. .

,.

,.

Author ized repr in t f rom

RILEM Bul le t in 14, 120-124(March , 1962)

Pub lis hed by

R un ion In t erna t iona l des Labor a t oi res d E s s a is et

,,

de RechercheS s ur les Ma t ia ux et les Const ruct ions . .,

,,

,,

.,,,P a r is , F ra nce ; . .. . . : ; .,:, .,

.

,,

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,.. .


2/18

PREVENTION OF FROST DAMAGE

TO GREEN CONCRETE

By

T. C. Powers

PORTLAND CEMENT ASSOCIATION

RESEARCH AND DEVELOPMENT LABORATORIES

5420OM Orcha rd Road

Skokie, Illinois

.. .. . . .

.

----


3/18

I

PREVENTION

OF FROST DAMAGE

TO GREEN CONCRETE

T. C. POWERS

Ce texte de M. T. C. Powers est une contribution apport~e

aux

travaux

du

groupe

de

travad

de la RiIem sur Ie ((B&tonnage

en hiver ))pr&id4 par M. N. M. Plum et qui avait &4 cn & la

suite du colloque qui sest tenu sur ce th&me &Copenhague,

en fdvrier 1956.

This report by Mr. T. C. Pou)ers is a contribution to the

work carried out by the Rilern Working Group on Winter

Concreting under the chairmanship of Mr N, M. Plum

and which was set up as a O11OUIp to the symposium held on

this subject

in

Copenhagen, in February 1956.

I

SUMMARY

(

If there is no exchange

of water

between a body of green concrete

and i t

surroundings, a~togenous desiccation

wi l j make the

cement

paste immune to damage by freezing after the time

when t he

satu-

ration coefficient of the capillary

spaces drops below a

certain

va/ue.

Data now uvailable

indicate the permissible upper /imit

of

saturation

t o

be about 97 ,

which

degree of

desiccation is reached

when the maturi t y

factor is 0,53 WOC,For curing at a given

temper-

ature, the necessary prehardening

t ime can be expressed

as a

f unc t ion of

time and water-cement ratio (Eq. 14).

The relative lengths of the necessary

prehardening

time can be

ca/cu/ated

f rom an

adaptation of the Arrhenius equation (Eq. 16).

120

-. --- . .. ... ----.-


4/18

MARS 1962 BULLETIN RILEM NO. 14

MARCH 1962

RESUME

Sil ny a pas d4change deau entre une masse de beton au

premier5ge et le milieu am biant. Iauto-dessiccation immunisera

la pate de ciment contre le gel apres un laps de temps au-dela

duquel Ie coefficient de saturation des espaces capillaires des-

cend au-dessous dune certaine valeur. Les donnees que Ion

possede actuellement indiquent la Iimite maximale acceptable de

saturation qui se situe aux alentours de 97 , Ie degrd de desicc-

ation correspondent dtant atteint quand Ie facteur de maturitd

est de 0,53 WOc. Pour la conservation A une temperature

donnde, Ie temps necessaire pour le prd-durcissement peut

iStre exprime, comme une fonction du temps et du rapport

eau-ciment (Eq. 14).

La durde relative du temps n4cessaire pour Ie pre-durcisse-

ment peut ~tre caiculee dapr+s une adaptation de Idquation

de Arrhenius (16).

INTRODUCTION

There are indications that to prevent damage when

green concrete is exposed to frost, time must be allow-

ed for a certain degree of hardening of the paste.

Accordingly, those concerned with concrete cons-

truction during cold weather have carried out various

experiments to determine the (( necessary prehard-

ening time )).

It has been suggested that the necessary

length of the prehardening period is fixed by the

length of time required for the attainment of a certain

minimum strength common to all concretes, and it

is therefore a function of the characteristics of the

cement, the water-cement ratio, and the prevailing

temperature. Expressing the state of hardening in

terms of strerwth seems to be based upon the belief

that cement p&te is able to acquire enough strength

to withstand the forces associated with freezing.

In view of the magnitude of stress that can be

produced by the freezing process, we must conclude

that immunity to damage after a certain time is not

due to the development of strength but to absence

of destructive force during freezing. Absence of

120-121


5/18


6/18

MARS 1962 BULLETIN RILEM NO. 14

MARCI+ 1962

The first term on the right-hand side gives the change

in water content due to autogenous desiccation [1];

it is proportional to the amount of non-evaporable

water, that amount being expressed as the< product

of the ultimate amount, w~/c,and the maturity factor

m.

The maturity factor is the ratio of the existing non-

evaporable water content to the ultimate non-evapo-

-.

rable water content at the time of complete hydration,

or the same for heat of hydration.

The coefficient 0.254

is valid for cements of various compositions. AZO

is the change of water content due to exchange with

the environment of the paste; it may be either a

positive or negative quantity.

The volume of capillary pores, p,, is given by

Eq. (3) :

p, = w~l),.

(Nl)nzco,.

(3)

The volume of capillary space is equal to the original

water content (corrected for bleeding), ZOo, minus

the net increase in volume of solids due to the consump-

tion of cement and production of gel. The latter

quantity is given by the second right-hand term.

N is the volume of cement-ge~ produced from 1 cc

of cement when the cement becomes hydrated. Expres-

sing quantities in terms of a unit volume of cement

paste, and the water content as water-cement ratio,

we obtain Eq. (4):

[

PC=C ~~ ~Ov,o Nl mti,

ficv. c

(4)

Substituting from Eqs. (2) and (4) into (1), we obtain

Eq.

5 : - -

[

AU)

1

0.254 ~ m ~ -I-- ~

v,,,

l S = Cl

00

7

For the present purpose,

ues that maybe used fo~

vW(Nl)mti,~

in fact for most purposes,

various portland cements

121

(5)

val-

may


7/18

PREVENTION OF FROST DAMAGE TO GREEN CONCRETE

be assigned to the constants. The values are: VW= 0.99

cc/g ; v~

= 0.319 cc:g (); N

=2. 1 cc,~cc. For portland

cements having chemical compositions within the

range of ASTM Type 1 and Type 111>URICmaY be

taken as 0.23 gjg; for cements corresponding to ASTM

Type 11, it maybe taken as 0.175. Using w~jc = 0.23

and the other values given, and assuming that AW*= O,

we obtain Eq. (6):

1

1

SC=

17.0200_06,

.

mc

(6)

MATURITY FACTOR

Let us now assume that to prevent damage to green

concrete when freezing occurs, SCmust not be larger

than some critical value, ~, and that this critical value

is the same for all portland cement pastes. On the basis

of this assumption, we may obtain an expression giving

the necessary maturity factor as a function of the

remaining variable, water-cement ratio.

The result

is Eq. (7J:

17.0 w.

m==

A

bc

where

b+

=

+ 6.0.

s

7

8

For practical purposes, it is desirable to express m as a

function of time and temperature. For a given tem-

perature,

m

has been found to be, for the

early stages

(1) This corresponds

by its displacement of

to the density of cement as determined

water [5].

121-122


8/18

MARS 1962

BULLETIN RILEM NO. 14

MARCH 1962

of hydration, a linear function of the logarithm of ti tie

as shown in Eq. (9) (1):

m =A+~log t.10.5>m> 0.11.

(9)

This is an empirical equation of limited validity, as

indicated. The upper limit depends on the water-

cement ratio of the paste, the higher the water-cement

ratio the higher the value of

m

at which the experimen-

tal points begin to fall below the values indicated by

the linear relationship. Since in the present case we

are interested in water-cement ratios within the usual

practical range, and only the early stages of hydration,

the limits stated will serve the purpose. The cons-

tants A and ~ depend on the speed of the cement.

For a particular ASTM Type I portland cement A has

the value of 0.385, and the value of ~ is 0.452. The

value of A is for time in days; for time in hours, the

corresponding value is 0.24.

From Eqs. (9) and (7) we obtain the following expres-

sion for the necessary prehardening time:

17.0u41_A

.

bc

logf= ~

lo

Assuming that

b

is the same for all conditions, we see

that the necessary prehardening time increases with

the water-cement ratio.

Since the higher the rate of

hydration at a given temper~tve the larger A and the

smaller i it follows alsu that prehardening time is

shorter the faster the cement.

These properties of

Eq. (1O) are in line with experience.

(1) Rastrup [3] developed a general equation which for some pur-

poses may be better than Eq. (9). In terms of maturity factor,

m, it 1s, for a given temperature,

m

=

mO + 1-me e af~t

where rno is a constant equal to about 0.038, t is time, and u is a

factor characteristic of the cement. However, Eq. (9) is easier to

use, and it serves the present purpose.

122


9/18


EVALUATION OF b

ANI) CRITICAL SATURATION COEFFICIENT

There are theoretical considerations by which one

might arrive at an estimate of the value of h in Eq, (1O).

However, it is not possible to predict the value with

adequate precision. . The factor can be evaluated

empirically from the test results given by Goran Mol-

ler [2]. From the length of prehardening time

necessary to prevent loss of strength when the specimen

becomes frozen, as indicated by his own tests, and

from data published by others, he drew the curve

shown in figure 1. It shows, for example, that for a

water-cement ratio of 0.64, the required prehardening

time is 20 hours. Using these values, together with

values already given for the other constants in Eq. (1O),

we

arrive at the required equation by the following

steps:

log t =

17.0 zg*+053

0.452 b C

(11)

For t = 20 hours, and ZOO/C= 0.64, Eq. (11) gives

b = 31.8.With this value (7) gives

and from Eq. (8)

Finally,

log

m= 0.53

UAJC

gives

s = 0.968.

t = 1.18u0 + 0.53.

12

13

14

c

Values calculated from Ea. (14) have been dotted

,.

.

as solid circles in figure 1, the calculated points being

spaced at even one-tenth intervals. The red shows

that evaluating b from one point on the experimental

curve was sufficient to establish practically perfect

-

agreement between the equation and the whole curve.

122


10/18

MARS 1962


MARCH 1962

The agreement between the semi-theoretical equa-

tion and Mollers curve indicating the maximum per-

missible lengths of prehardening time suggests that

the laboratory conditions under which the experiments

giving the uppermost points in figure 1 were made

were such that little or no water was gained or lost

during the prehardening period. Points falling below

this level, those representing specimens requiring

relatively short prehardening periods at a given water-

cement ratio, perhaps represent differences in the

speeds of the cements,

They may represent also -

experimental conditions that allowed some water to

evaporate from the specimens during the prehard-

enirw ~eriod. This would mean that if the amount of

wate~ lost could be evaluated, the prehardening time

could be calculated from an equation developed from

Eq. (5). However, there would seem to be no good

reason for developing such an equation since it would

not be good practice to depend on evaporation of water

as a means of shortening the prehardening period.

For water-cement ratios within the range found in

concretes of acceptable quality, the prehardening time

at normal temperature without loss of water by eva-

poration is not over 24 hours.

EFFECT OF TEMPERATURE

The rate of hydration at a given temperature n~ay,

for practical purposes, be stated in terms of

the

matu-

rity factor as follows:

dm

dt

where t is time and

rate. The function

= ~ ~ m,

IJ o c

(15)

~ is the Arrhenius specific reaction

0

m, tin/c

is unknown, but is un

doubtedly a complex one. For-a paste of given ZOo/c,he

time required to reach a given stage of hydration,

m,

is

122-123


11/18


inversely proportional to }t, and ~ is a

perature.

The temperature function

the form of the Arrhenius equation:

11

function of tem-

can be stated in

,

16

r

~ 60

I

+

?

o MOller (1959)

v-

D Bernhardt(1954)

6 50

A McNeese (1952)

\

+

N

+ Scofield (1937)

I

+

G

V Graf

(1927)

Q 40

E

x Kreuger (1922)

F

.-

1-

Equation 14

I

+

. 3

I

6 () +

c

~ 20

L

+

I

>

Cm

s

J

O

m 10

u-l

o @

a

v

x

x

Al cement

VA/, cement ,

2

0

I

0.3 0.4 0.5 06 07 08 09

I .0

1,1

Water Cement Ratio (wt.)

F IG . 1.

Da t a from Gora n Moller compa red w it h ca lcula t ed

.

results ,

Eq.

(14).

The curve is as drawn

by

Moller

.

where C is a constant characteristic of the system,

T ~~~

.

is the absolute temperature, and q is a constant which

in the present case is related to the energies of activa-

tion of the hydration reactions in some way not clearly

definable at present.

Thus, the relative time required

to reach a given stage

of hydration can be stated

as follows:

t ko = ,9(;-*)

-=

k

(17)

to

or,

log t/tcl

- .

18

where Q

= 0.4343 q.

123


12/18

.-

-., .

----

..

MARS 1962 BULLETIN RILEM NO, 14

MARCH 1962

There are reasons to believe that Q might not be

wholly independent of either

m

or T, but at the pre-

sent state of knowledge of the kinetics of cement hydra-

tion such possible complications cannot be dealt with

Equation (18) may pro~e satisfactory for practical use.

The best available data on rate of reaction is in terms

of rate of heat evolution.

The amount of heat evolu-

tion per unit amount of chemical reaction is smaller

the higher the temperature. A correction could be

made, but over the temperature range of interest here,

it is not worth while to do so.

By fitting experimental

data, Rastrup found that for a Type I cement the rate

of heat evolution doubled for a temperature rise of

100 C. On this basis,

Q of equation (18) can be eva-

luated as follows:

For T = 283 and TO = 293,

log

2 =

11

Q(~3~

)

Q = 2508

For T = 273 and TO

Q = 2315.

Therefore, for the range 0-20 C, a value of 2400

would be adequate

for practical purposes. For

Mollers data we may write:

= 0.301.

= 283

log t =

L18~0 + 0.53 + 2400

c

(+-A) 1)

COMPRESSI~ STRENGTH

It has already been reported that the compressive

strength of concrete at any we -, be

represented bY

an empirical equation of the following form.

123


13/18

I

PREVENTiON OF FROST DAMAGE TO GREEN CONCRETE

where~C is compressive strength, A is a constant cha-

racteristic of the materials,

and the rest of the symbols

are as defined before.

Strength at the end of the

necessary prehardening period can be calculated from

this relationship.

From q

7

and Eq. (12), and

/

etting titi, u, = 3.1, N =

2.1, and

n =

3, Eq. (20

becomes

f

= 0.029A.

(21)

c

For a cement of average C~A content, and with a

siliceous aggregate, the value of A is about 14,000 psi

or 980 kglcmz. On this basis, Eq. (21) indicates that

when concrete made with such a cement reaches the

end of the necessary prehardening period, its strength

will be about 406 psi or 29 kg/cm2.

The latter result is to be compared with the following

statement in

Goran Mollers paper. Referring to

his own experiments he said, lt wa~ found that m all

cases the necessary prehardening

time corresponded

to a compressive strength of about 30 kg/cm2. Th~s

value is in close agreement with a statement which 1s

often met with in literature

according to which a

strength o{ which 35 kg/cm2 is sufficient to make a

concrete resistant fo freezing:

DISCUSS1ON

It seems to be pretty well established that green

.

concrete is safe from damage by freezing when :S

maturity factor reaches a

value equal to about 53/0

of the water-cement ratio,

(Eq. 12), or a strength of

about 430 psi (30 kg~cm2). At normal temperature,

123-124

...

__ -----


14/18

MARS 1962


MARCH 1962

this stage would generally be reached within the first

24 hours. These figures are based on the proviso

that no curing water be supplied to the cement paste

during this period.

/

Individual aggregate particles must also have water

contents below their respective critical saturation

points; otherwise, freezing in the aggregate could

cause disruptive expansion whether freezing in the

paste does or not.

The safety from frost damage arising from auto-

genous desiccation maybe temporary. If the specimen

obtains water from the outside, it may become vulner-

able to frost.

This may happen relatively quickly if

the paste is not protected with entrained air.

.

REFERENCES

[4]

[2]

[3]

[4]

[5]

L. E . COP ELAND a nd R. H . B RAG C. (( Self-Desicca tion

in P ort la nd Cement P a stes )). ASTM Bullet in 204, 1955.

P CA Resea rch B ullet in 52, 1955.

G ORAN MOLLE R.

(f Resist a nce of Concrete t o E a rly

Frost Act ion )}. Summa ry prepa red for RILEM Com-

mit t ee on Winter Concret ing, J une 7, 1960. Also, P roc.

RILE I I Symposium on Wint er Concret ing, Copenha gen

2956.

ER IK RASTRUP .

((The Tempera ture Funct ion for H ea t

of Hydra t ion in Concret e V.

P roc. RILEM Symposiun]

011Winte r Concret ing, Copenhagen , 1956.

GEORGE VERBECK.

((Energet ic of t he Hydra t ion of

P ort la nd Cement )). For thcoming P roceedings Fourth

Int erna t iona l Symposium on the Chemist ry of Cement ,

1960.

C . L. FORD .

((D et ermina t ion of t he Appa rent D ensit y of

H ydra ulic Cement in w at er U sing aVacuum Pyenometer)).

ASTM B ullet in no 231, J u1y 1958. P CA. Resea rch B ulle-

t in 101, 1958.

124


15/18

Bulletins Published by the

Research Department

I

I

1000

..

101.

102.

103.

104.

105.

106.

107.

108.

1 9

110.

111.

Research and Development Laboratories

of the

,

Portland Cement Association

List of P ublished B ullet ins a nd P apers of t he Resea rch Depa rtment ,

May, 1959

(Also list s ea r lier resea rch pa pers of t he P ort la nd Cement

Association).

D etermina tion of t he Appa rent D ensit y of H ydra ulic C ement in Wa ter

U sing a Va cuum P ycnometer , by C . L. FORD.

Reprinted from ASTM Bu llet in , No. 231, 81-84 (J u ly , 1958).

Long-Time S tudy of Cement P erforma nce in Concret eChapter 11.

Report on Condit ion of Three Test P avement s Aft er 15 Yea rs of S erv-

ice, by FRANK H . J AC KS ON.

.

Reprinted from

Journa l

of

t he America n C on cr et e I nst it ut e (J u ne, 1958); P ro-

ceedings, 54, 1017-1032(1957-1958).

E ffect of Mixing a nd Cur ing Tempera ture on Concret e S t rength, by

P AU L K LI EG E R.

R epr in ted fr om J o ur na 2

of

t he Am er ica n C on cr et e I nst it ut e (J u ne, 1958); P ro-

ceedings, 54, 1063-1081(1957-1958).

The Successive Det ermina tion of Ma nga nese, Sodium a nd P ota ssium

Oxide in Cement by Flame P hotomet ry , by C . L. FORD.

Repr in t ed f rom ASTM BuUet in , No. 233, 57-63 (Oct ob er , 1958).

The Sur fa ce Energy of Tobermorit e, by STEP HENB RUNAU ER,D . L.

KANTRO

a nd C . H .

WEISE.

R epr in ted fr om C a na d ia n J o ur na l oj C her nkt w , 37, 714-724 (Apr il, 1959).

The Flow of Wa ter in Ha rdened P ort la nd Cement P a ste, by T. C .

P OWERS ,H , M. MANN a nd L. E . COP ELAND.

R epr in ted fr om H ighwa y R es ea r ch B oa r d S pecia l R epor t 40, 308-323 (1958).

The B a ll-Mill H ydr at ion of Tr ica lcium S ilica t e a t Room Temper at ur e,

by

D L KANTRO STEPHENBRUNAUER a nd C . H .

WEISE.

Repri nt ed f rom

Journa l

of Col loid Sci ence, 14, 363-376 (1959).

Qua nt it a t ive Det ermina t ion of the Four Ma jor P ha ses of P ort la nd

Cement by Combined X-Ra y a nd Chemica l Ana lysis, by L. E , CoP E-

LAND , S TE PH EN B RUNAUER, D . L. KANTRO, E DITH G .

SCHULZa nd C. H .

WEISE,

R epr in t ed f rom Ana ly tica l Chem is tr y, 31, 1521-1530 (S ept ember , 1959).

Funct ion of New P CA Fire Resea rch La bora tory, by C . C . CARLSON.

Reprintedfrom the J ourna l of the P CA Resea rch a nd Development La bora -

t ories, 1, No. 2, 2-13 (Ma y, 1959).

Ca pilla ry Cont inuit y or D iscont inuit y in Cement P a stes, by T. C .

P OWERS ,L. E . C OEUZANDnd H . M. MANN.

Reprintedfrom the J ourna l of the P CA Resea rch a nd Development La bora -

t or ies, 1, N o. 2, 38-48 (Ma y , 1959).

Petrography of Cement a nd Concret e, by L. S . B ROWN.

-..

Reprint ed from the J ourna l of the

t or ies , 1, N o. 3, 23-34 (S ept em ber ,

P CA Resea rch a nd D evelopment La bora -

1959).


16/18

112.

113.

114

115.

116.

117.

118.

119.

120.

121.

122.

123.

124.

125.

The G ra vimet r ic Determina t ion of S t ront ium Oxide in P ort la nd

Cement , by C . L, FORD.

Reprintedfrom ASTM Bu llet in , No. 245, 71-75 (Apr il, 1960).

Qua nt it a t ive Determina t ion of the Four Ma jor P ha ses in P or t la nd

Cement by X-Ra y Ana lysis, by STE PH ENB RUNAU ER,L. E . COP ELAND ,

D. L. KANTRO, C . H . WEISE a nd E DITH G . SCHU LZ.

R epr in ted fr om P r oceed in gs of t he Amer ica n S ociet y for Test in g Ma t er ia ls, 59,

1091-1100(1959).

Long-Time S tudy of Cement P er forma nce in Concret eCha pt er 12.

Concret e Exposed to Sea Wa ter a nd Fresh Wa ter , by I . L. TYL~ ,

Reprintedfrom

Journat

of t he America n Concret e Inst it ute

(March, 1960);

Proceedings , 56, 825-836 (1960).

A G ra vimetnc Method for the Determina tion of B ar ium Oxide in P ort -

la nd Cement , by C . L, FORD .

Reprintedfrom

ASTM Bullet in , No. 247, 77-80 (J u ly , 1960).

The Therm odynamic F unct ions for t he S olut ion of C alcium H ydroxide

in Wa ter , by S , A.

GREENBERG a nd L. E . COPELAND.

Reprint ed from J ourna l OJ P h@ca l Che?nistw, 64, 1057-1059(August , 1960).

I nvest iga t ion of C olloida l H ydra ted S ilica tes. I . Volubilit y P roduct s,

by S . A. GREENBERG ,. N. CHANGa nd ELAINEANDERSON.

Reprint edfrom

J o ur na l of P h ~ s ica l C h em is t ry , 64, 1151-1156(Sept ember , 1960).

Some Aspect s of Dura bilit y a nd Volume Cha nge of Concret e for P re-

st ressin g, by PAULKLI EGER.

Remintedfrom

t he .lourna l of t he P CA Resea rch a nd Development La bora -

tories, 2, No. 3, 2-12 (Sept ember , 1960).

Concret e Mix Wa terHow Impure Ca n I t B e? by HAROLDH . STE INOUR .

Repr int ed from the J ourna l of t he P CA Resea rch a nd Development La bora -

t or ies, 2, N o. 3, 32-50 (S ept ember , 1960).

Corrosion of P rest ressed Wire in Concret e, by G , E . MONFOREand

G . J . VERB ECK.

Repr int edfrom

JouT?td of

t he AmeTica n C on cr et e I ns tit ut e (November , 1960):

P r oceed in gs , 57, 491-515 (Sept ember , 1960).

Freezing a nd Tha wing Test s of Lightw eight Aggrega te Concret e, by

P AU L KLI EG ER

and J . A.

HANSON.

Repr in t ed f rom

Jownat

of

the

Amer ica n C on cr et e I nst it ut e (J a n ua ry , 1961):

P roceedings , 57, 779-796 (1961).

A C ement -Aggrega te Rea ct ion Tha t Occurs Wit h C er t ain S and-G ra vel

Aggregates,

.b


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126.

127.

128.

.

129.

130.

131.

132.

133.

134.

135.

136.

..

137.

.

138.

139.

Influence of P hysica l Cha ra ct er ist ics of Aggrega t es on Frost Re-

sist a nce of C on cr et e, by GEORGEVERBECKn d ROBERTANDGRE IV.

Rep rint ed f rom

Proceedings of the American Societv for

Tes tin g Ma ter ia l s, 60,

1063-1079(1960).

Determina tion of t he Free C a lcium Hydroxide Content s of Hydra ted

P ort la nd Cement s a nd Ca lcium S ilica t es, by E , E , P RESS~ ER,STEPHEN

BRUNAUER,D . L. KANTRO,a nd C . H . WE IS E.

Reprin tedfrom

Analytical Chemistry, 33, No.

7, 877-882 (J une, 1961).

An X-ra y Diffra ct ion Invest iga t ion of Hydra ted P ort la nd Cement

P a st es, by D . L. KANTRO,L . E . COPELAND ,nd ELAINER . ANDERSON .

Rep rint ed f rom

Proceedings of the American Society for

Tes tin g Ma ter ia ls , 60,

1020-1035(1960).

D imensiona l Cha nges of Ha rdened P ort la nd Cement P astes Ca used

by Tempera ture Cha nges, by R. A. HE LMUTH.

Reprin t edfrom Hi@nvav Research Board Proceedings , 40, 315-336 (1961).

P r ogr ess in t he C hem ist ry of P or tla nd C emen t, 1887-1960, by HAROLDH .

STEINOUR.

Reprintedfrom the

Journal of

t he P CA Resea rch

and

Developmen t L a bor a -

t or ies, 3, No. 2, 2-11 (Ma y, 1961).

Resea rch on Fire Resist a nce of P rest ressed Concrete, by HUBERT

WOODS,in clud in g discussion by V. PASCHKI S,a nd a ut hor s closur e.

Reprintedfrom

Journal oj

t he S tr uct ur al D ivision , P r oceed in gs of

the Ameri-

can Society oj

C iv il En gin eer s, PTOC.Paper 2640, 86, ST 11, 53-64 (November ,

1960); D is cu ss ion , 87, ST 2, 59-03 (F eb ru aW, 1961): C los ur e, 87, ST 51 81

( JUIW

1961).

Cent ra lized Cont rol of Test Furna ces in the P CA Fire Resea rch La bo-

ra tory, by P H IL J . TATMAN.

Reprintedfrom t he J ourna l oj the P CA Resea rch and Development Labora-

tories, 3, No. 2,

22-26 (May , 1961).

A P roposed S imple Test Method for Determining t he P ermea bilit y of

C on cr et e, by I . L , TYLERa nd BERNARDERL IN.

Repr int ed from t he

Journal oj the

P CA Resea rch a nd D evelopment La bora -

t or ies, 3, No. 3, 2-7 (S ept em ber , 1961).

The B eha vior a t H igh Tempera ture of S t eel S t ra nd for P rest ressed

Concret e, by M. S , AB RAMSa nd C . R. CRUZ.

Repr int ed fr om t he

JournaC of the PCA Research and

Dev elopmen t L a bor a -

t or ies , 3, N o. 3, 6-19 (S ept em ber , 1961).

E lect ron Opt ica l Invest iga tion of. the H ydra tion P roduct s of Ca lcium

S ilica t es a nd P or tla nd C ement ,

by L. E . C OP ELANDnd EDITHG . S CHULZ.

Repr int ed from t he.

Journat of

t he

PCA Resetirch and Development Labora-

tories, 4, No. 1, 2-12 (J a n u a r y, 1962).

S oil-C emen t Tech nologyA Resume, by MI LESD . CATToN.

Reprintedfrom the

Journal of the

PCA Res ea r ch

and Development

Labora-

t or ies 4, No. 1, 13-21 (J a n ua ry , 1962).

S urfa ce Tempera ture Mea surement s With Felt ed Asbestos P ads, by

M. S . ABRAMS .

Re xint ed from t he J ourna l of

the

PCA Res ea r ch

and

Dev elopmen t L a bor a -

t or ies, 4, No. 1, 22-30 (J a n ua ry , 1962).

Tobermor it e G elTh e H ea r t of C oncr et e, by STEPHENBRUNAUER.

Reprfntedfrom the Arn= kan scief it~ st ,50, No. 1, 210-229Ma rch, 1962).

Alka li Rea ct ivit y of Ca rbona te RocksE xpa nsion a nd D edolomit iza -

t ion , by DAVIDW. HADLEY.

Reprintedfrom Hi9hwa gResearch Board PToCeedin9s,40, 462-474(1961).

.


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140. Development of Surfa ce in the Hydra t ion of Ca lcium S ilica t es, by

D . L. KANTRO, STEPHEN 13RUNAUER, a nd C . H . WEISE.

Reprinted

from

Solid Surfaces and the Gas-Solid Interface, Advances

in

Chemist ry Ser ies 33, 199-219 (1961).

141 Thermodyna mic Theory of Adsorpt ion, by L. E . COP ELANDnd T. F.

YOUNG.

Repr int ed from Solid Sur fa ces a nd

Chemist ry Ser ies 33 , 348-356 (1961),

t he G as. S olid Int erfa ce, Adva nces in

a nd

Thermodynamics of Adsorpt ion. B a rium S ulpha te-Wa ter S yst em, by

Y. C . Wu a nd L. E . COP ELAND,

Repr int ed from Solid Surfa ces a nd the G as-Solid Int erfa ce, Adva nces in

Chemist ry Ser ies 33, 357-368 (1961).

142. The New B eam Furna ce a t P CA and Some Experience G ained from

It s U se, by C . C . C ARLSONnd P HIL J . TATMAN.

Reprintedfrom symposiumon Fire Test

Methods.

ASTM Special Technical

Publication No. 301, 41-59 1961).

143

New

Techniques for Tempera ture a nd H umidit y C ont rol in X-Ra y D if-

fra ct omet ry , by P AU LS ELIGMANNnd N, R. G RE ENING .

RePrintedfrom the

Journal oj

t he

PCA Research and Development Labora-

t or ies, 4, No. 2, 2-9

(May,

1962).

144. An Opt ica l Met hod for D et ermining t he E la st ic C onst ant s of C oncret e,

by C . R.

CRUZ.

Repr int ed from t he J ourna l of the PCA Research and Development Labora-

tories, 4, No. 2, 2432 (Ma y, 1962).

145. P hysica l P roper t ies of Concret e a t Very Low Tempera tures, by G . E .

MONFOREnd A. E . LENTZ.

Repr in tedf rom the J ourna lof the PCA Research and Development Labora-

tories, 4, N o, 2, 33-39 (Ma y , 1962).

146 A Hypothesis on Ca rbona tion Shr inka ge, by T. C . P OWERS.

Reprintedfrom the J ournalof the PC A Research and Dev elopmen t L a bor a -

t od es, 4, No. 2, 40-50 (Ma y, 1962).

147

Fire Resist a nce of P rest ressed Concrete B ea ms, S tudy A Influence

of Thickness of Concret e Covering Over P rest ressing S teel S t ra nd, by

C . C . C ARLSON.

P ubkMd by P ortla ndCementAssociat ion,Resear cha ndDevelopmentLa bora-

tories, skokie,lllinois, (J uIY, 1962).

148. P revent ion of Frost Damage to G reen Concret e, by T. C . P OWERS.

Reprintedfrom R6unionInternational des La bora toires dE ssa is et de Re-

cherches sw les Materiauz et les Constructions, R ILEM Bu llet in 14, 120-124

(March , 1962).

P r in t ed in U .S .A.

Prevention of Frost Damage

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