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_ \...IE-CProperty of the United States Governm

MISCELLANEOUS PAPER C-78-9

INVESTIGATION OF METHODS FOR EXTRACTION, DETECTION, AND

IDENTIFICATION OF WATER-SOLUBLE ADMIXTURES IN CONCRETE

by

Dennis L. Bean, Tony B. l-lusbands

Concrete Laboratory U.S. Army Engineer Waterways Experiment: Station

P. 0. Box 631, Vicksburg, Miss. 39180

August: 1978 Final Report:

Approved For Public Release; Distribution Unlimited

Prepared for Assistant: Secretary of the Army (R&-0) Department: of the Army, Washington D. C. 20310

Under Project: 4A06 I I 0 I A 91 D

DBRA BRAN TECHNICAL INFORMATION CfNTrn

'LHA V ~Nl:?lf\jf:E 1c.n ' ,R WATERWAYS EXPERIMENT STATION

<:::R I r: I ID , __ _

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Miscellaneous Paper C-78-9 4. TITLE (and Subtltl•) 5. TYPE OF REPORT & PERIOD COVERED

INVESTIGATION OF METHODS FOR EXTRACTION, Final report DETECTION, AND IDENTIFICATION OF WATER-SOLUBLE ,___

5. PERFORMING ORG. REPORT NUMBER ADMIXTURES IN CONCRETE

7. AUTHOR(•) a. CONTRACT OR GRANT NUMBER(•)

Dennis L. Bean Tony B. Husbands 9. PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM ELEMENT, PROJECT, TASK

u. s. Army Engineer Waterways Experiment Station AREA & WORK UNIT NUMBERS

Concrete Laboratory Project No. 4AOGll01A91D P. 0. Box 631, Vicksburg, Miss. 39180

11. CONTROLLING OFFICE NAME AND ADDRESS 12. REPORT DATE

Assistant Secretary of the Army (R&D) August 1978 Department of the Army 13. NUMBER OF PAGES

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Adm~ ;:turr,:.; Conc~ete 'lrlrni xtures

2Q. ABSTRACT (Continue ~ rev1'1ri9e eltl• f.t n~•«ty IJltJd lden..tlty by block number)

Methods [or detecting, identifying, and quantitatively measuring carbo-hydrates and salts o[ hydroxyl.:1ted carboxylic-acid admixtures in concrete were investigated. Two published methods for c!Ptecting sugar and an unpublished method for detecting both sugar and sodium gluconate were evaluated. Other methods investigated included: thin-layer chromatography, inf rared spectros-copy, and high-pressure liquid chromatography.

(Continued)

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20. ABSTRACT (Continued). Sugar could be detected in cement mortar at an early age using both of the

two published methods and the unpublished method. Approximately quantitative measurement of sugar could be made by the unpublished method and a UV spectro­photometer. Quantitative measurements with age indicated that sugar was being converted to another compound. Because of this conversion, sugar could not be detected by the UV method in 7-day-old mortar specimens containing 0.05 percent sugar.

An infrared spectroscopic method for identifying and quantifying salts of carboxylic acids in concrete was investigated and was found to be unsatisfactory because of interference from water-soluble constituents in the cement paste. Six organic solvents were investigated for extracting salts of carboxylic acids from concrete, and none of the solvents were found suitable.

Thin-layer chromatography (TLC) methods were found not to be sufficiently sensitive to detect the small amounts of carbohydrates present in concrete. Salts of carboxylic acids could not be separated using TLC, by the methods tried. A combination TLC and fluorometric method for quantifying carbohydrates was investigated. This method showed some promise but could not be fully evalu­ated because of the lack of a scanning fluorometer.

A high-pressure liquid chromatography (HPLC) method for separating and identifying the admixtures was investigated. The admixtures could not be detected because of interference and the low concentration of the admixtures in concrete. HPLC shows promise as a method and warrants further investigation.

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1

SUMMARY

Methods for'detecting, identifying, and quantitatively measuring

carbohydrates and salts of hydroxylated carboxylic-acid admixtures in

concrete were investigated. Two published test methods for detecting

sugar and an unpublished method for detecting both sugar and sodium

gluconate were evaluated. Other methods investigated included: thin­

layer chromatography (TLC), infrared spectroscopy (IR), and high-pressure

liquid chromatography (HPLC).

Sugar could be detected in concrete by the two published methods

and by the unpublished method. Sodium gluconate could also be detected

in concrete by the unpublished method. Approximate quantitative measure­

ments of sugar can be made by the unpublished method using a UV spectro­

photometer. Mortar specimens containing 0.05 percent sugar were analyzed

by the unpublished method. Test results indicated that sugar content

decreased with increasing age, and sugar could not be detected after

7 days. Sugar in concrete is either being converted to another compound

or broken down into other compounds by the reaction with the cement paste.

The IR methoq for identification and quantitative measurements of

salts of carboxylic acids in concrete was found to be unsatisfactory.

Mortar specimens containing known amounts of sodium gluconate were

extracted with hot water and the extract was analyzed by IR. The hot-water

extract contained high amounts of dissolved constituents from the cement

paste, and these dissolved constituents inter£ered with the IR analysis.

In order to eliminate this interference, different organic solvents were

investigated for extracting the admixture from concrete. None of the

solvents were found to be suitable.

Several TLC methods for separating and identifying carbohydrates

and salts of carboxylic acids were investigated. Sugars in water could

be separated and identified by one of the TLC methods investigated, but

the method was not sufficiently sensitive to detect the amount of carbo­

hydrates normally found in concrete. Salts of carboxylic acids could

not be separated using the TLC methods. A combination TLC and fluoro­

metric method for quantifying carbohydrates was investigated. This

2

method showed some promise, but could not be fully evaluated because of

the lack of a scanning fluorometer.

HPLC was investigated for separating and identifying the admix­

tures in concrete. The HPLC method was not successful because of inter­

ference from the dissolved cement-paste constituents, and the detection

limit using the refractive index detector was not as low as desired.

HPLC shows promise as a method for separating and identifying these

admixtures and warrants further investigation.

3

PREFACE

The study reported herein was funded by Department of the Army Proj­

ect 4A061101A91D, "In-House Laboratory Independent Research Program,"

Item AR, sponsored by the Assistant Secretary of the Army (R&D). The

study was conducted during the period October 1974 through September 1977

at the U. S. Army Engineer Waterways Experiment Station (WES) Concrete

Laboratory under the supervision of Mr. Bryant Mather, Chief, and

Mr. Leonard Pepper and Mrs. Katharine Mather.

Commanders and Directors of the WES during the conduct of this

study and preparation of this report were COL G. H. Hilt, CE, and

COL J. L. Cannon, CE. Mr. F. R. Brown was Technical Director.

4

SUMMARY •

PREFACE

PART I:

CONTENTS

INTRODUCTION •

PART II: PUBLISHED TEST METHODS AND TEST RESULTS

Published Test Methods ... Test Results

PART III: OTHER TEST METHODS INVESTIC-ATED AND TEST RESULTS

Infrared Spectroscopy . . . . . . . • Thin-Layer Chromatography . . . . . High-Pressure Liquid Chromatography

PART IV: CONCLUSION AND RECOMMENDATIONS .•

Conclusion Recommendations .

REFERENCES. . .

TABLES 1 and 2

FIGURES 1-9

5

Page

2

4

6

7

7 8

10

lO 11 13

15

15 16

17

INVESTIGATION OF METHODS FOR EXTRACTION, DETECTION, AND

IDENTIFICATION OF WATER-SOLUBLE ADMIXTURES IN CONCRETE

PART I: INTRODUCTION

1. Admixtures are frequently added to concrete mixtures to improve

the properties of the concrete. Addition of incorrect amounts of an ad­

mixture can have deleterious effects on the properties of the unhardened

and hardened concrete. Whenever the anticipated concrete properties are

not obtained in a structure and admixtures have been incorporated into

the mixture, it is helpful to have methods to detect, identify, and mea­

sure the quantity of admixture incorporated in the hardened concrete.

Unfortunately, such methods have not been published for admixtures which

are essentially carbohydrates or salts of hydroxylated carboxylic acids.

There are published methods1 ' 2 available for detecting carbohydrates

such as sugar and corn syrup; however, these methods cannot be used to

identify or measure the ,quantity present.

2. This investigation attempted to find ways of removing carbohy­

drates and salts of carboxylic-acid admixtures from concrete and to develop

methods to detect, identify, and measure the quantity of the admixture

present in the concrete. Certain carbohydrates are believed to be con­

~rLed _to _uther compounds upon bein_g incor~orated into the concrete;

therefore, the conversion or binding of these carbohydrates to other

compounds was investigated.

3. Portland-cement mortar containing known amounts of admixtures

classified as carbohydrates and salts of carboxylic acid were made and

cured to various ages. At the desired ages the mortar was pulverized

and the admixtures extracted with water and other solvents. Detection

of the admixtures in the extract was sought using TLC, IR, UV, and HPLC.

6

PART II: PUBLISHED TEST METHODS AND TEST RESULTS

Published Test Methods

4. Published methods for detecting carbohydrates and salts of

carboxylic acids in concrete were reviewed. Only two methods for 2 detecting sugar in concrete were found: a method by Figg and Bowden ,

and method CRD-C 213-48 found in the Handbook for Concrete and Cement. 1

Both methods are qualitative and not quantitative. No published methods

for detecting salts of carboxylic acids were found.

5. The Figg and Bowden method consists of extracting the sugar

with water and neutralizing the extract by bubbling carbon dioxide

through the water until the lime is carbonated. Acid is then added to

invert the sucrose, then neutralized with sodium hydroxide. Fehling's

solution is then added and the solution brought to a boil. If sugar is

present, the blue color will be discharged and cuprous oxide precipitated.

6. Test method CRD-C 213-48 consists of extracting the sugar with

water. The extract is then filtered into a test tube and alpha-naphthol

added. Sulfuric acid is then poured into the test tube, and if sugar is

present, a bright violet ring will form at the plane of separation of the

two solutions.

7. Another method for detecting sugar and sodium gluconate in con­

crete was obtained from the Portland Cement Association (PCA). 3 This

method has not been published. The method is similar to the method found

in CRD-C 213-48, in that alpha-naphthol is used to develop the color

change. The method consists of extracting the sugar and sodium gluconate

from the concrete with boiling water. An aliquot of the extract is then

added to cold sulfuric acid. The mixture of sulfuric acid and the extract

is then heated in boiling water in a test tube. The mixture is allowed

to cool, and a 2 percent alcoholic alpha-napthol solution added. If

sugar is present, the solution will turn a deep purple immediately. If

sodium gluconate or potassium gluconate is present, the solution will

slowly turn to a wine red.

7

8. Interference from the presence of other organic compounds was

not investigated for these test methods. These methods would only be

good to detect whether certain carbohydrates were present. Better test

methods for confirming the admixture and making quantitative measurements

are needed. Figg and Bowden reported that their procedure could be made

quantitative, and personnel from PCA also said that approximate concen­

trations of sucrose and sodium gluconate could be determined by measuring

the intensity of the color change using a UV spectrophotometer.

Test Results

.. 9. To evaluate the published test methods and other test methods

investigated by the laboratory, 2-in. mortar cubes containing different

admixtures were molded using the mortar proportion from CRD-C 302-68. 1

The admixtures sugar, corn syrup, sodium gluconate, and Plastiment were

each added to the mixing water before mixing one batch of mortar. The

amount of each admixture added to the mortar was 0.2 percent by weight

of cement or 0.05 percent by weight of mortar. The mortar cubes were

stripped from the molds after 24-hr curing in the moist cabinet and

wrapped with Parafilm brand flexible wax film to prevent moisture loss.

At different ages the mortar cubes were gr.ound to pass a 150-µm (No. 100)

sieve. Portions of the ground mortar were then used to evaluate different

extraction techniques and test methods.

10. Two-day-old mortar cubes containing sugar and Plastiment were

used to evaluate the three test methods described. All three test methods

showed a positive test for sugar by the appropriate color change. The

test method furnished by PCA also showed a positive test for Plastiment.

The method furnished by PCA was chosen for further investigation because

of the following reasons:

a. The color change was more intense than in the other test methods.

b. The method can be used to detect Plastiment.

c. Quantitative measurement is possible using UV.

8

11. The procedure was then evaluated to determine whether quantita­

tive measurement of sugar could be made using the UV spectrophotometer.

Standards containing 5, 10, 20, and 50 µg/m£ of sugar were prepared in

distilled water. A standard curve for sugar was determined following

the test method, and the absorbance was read at 322 nm. The calibration

was not very linear (Figure 1), but absorbance did increase with higher

concentrations indicating that approximate concentrations could be deter­

mined.

12. Quantitative measurements of sugar in mortar were made using

the test method. A mortar specimen 2 days old containing 0.05 percent

sugar by weight of mortar was analyzed. Three portions of the ground mor­

tar, i.e. 10, 20, and 30 g, were extracted individually with 40 mi of ~water.

The extracts were then diluted to 100 mi before being analyzed. Absorbance

readings were made for each sample, and the results are shown in Table 1.

The percentages of sugar found in the samples were 48, 32, and 32 percent,

respectively, of the amount added. Test results indicate that the sugar

is converted to another compound.

13. A mortar specimen 4 days old made from the same mixture was

analyzed using the same weights. The test results are shown in Table 2.

The percentage of sugar found in the samples was less than 10 percent of

the amount added. These test results also indicated that sugar was being

converted to another compound. To verify this, a mortar specimen 7 days

old made fro111 the same- mixture- was- analyzed. Only- 20- and 30-g- portions

of the mortar were analyzed. No sugar was detected in either sample,

indicating that the sugar had been converted to another compound after

7 days.

9

PART III: OTHER TEST METHODS INVESTIGATED AND TEST RESULTS

14. The published test methods reviewed are only useful for de­

tecting sugar, and the interference from other organic compounds has not

been investigated. Test results have also shown that sugar was con­

verted to another compound when placed in concrete. Better methods

are needed for detecting, confirming, and measuring the amounts of

sugar present, of carbohydrates, and of salts of carboxylic-acid

admixtures in concrete. Methods for detecting and measuring these

admixtures, including TLC, HPLC, and IR, were investigated. Gas chroma­

tography (GC) was also considered as a method for detecting these ad­

mixtures, but only a literature search of this method was made.

Infrared Spectroscopy

15. The detection and quantitative measurement of salts of car­

boxylic acids in concrete were investigated using an IR spectrophotometer.

Infrared spectra were obtained in the 2.5-16 µm region. Salts of car­

boxylic acids can be identified by their carboxylate group (Coo-) which

has strong bonds between 6.lto 6.3 µm and 7.1 µm.

16. A standard containing 5 percent Plastiment in distilled water

was prepared to determine what 'concentrations of the admixture could be

·detected by IR. IR is not as sensitive as some other instruments for

detecting low concentrations of organic compounds. Low concentrations

of Plastiment (50 µg/m£) like that obtained in the water extract would

be difficult to detect using IR. Three potassium bromide (KBr) pellets

were made by injecting small aliquots of the standard 10, 20, and 30 µ£

on top of 0.40-g portions of dried KBr. The KBr containing the Plasti­

ment was then dried at 105 C, mixed, and pressed into pellets. The

three KBr pellets contained 500, 1000, and 1500 µg of Plastiment. The

KBr pellets were analyzed by the IR spectrophotometer, and the IR spectra

are shown in Figures 2, 3, and 4.

17. The strongest band for the spectra was observed at 6.2 µm.

Another band was observed at 7.1 µm indicating the carboxylate group ~as

10

present. The absorption of the bond at 6.2 µm increased as the amount

of Plastiment increased, indicating that quantitative measurements could

be made. Absorption was converted to absorbance, and the absorbance

versus concentration is shown in Figure 5.

18. KBr pellets were prepared using a hot water extract from a

4-day-old mortar specimen containing Plastiment. Based on the detection

limit using the IR method, 5-ml and 10-ml aliquots of the extract were

added to 0.40 g of KBr and dried at 105 C overnight. The dried KBr was

then ground and pressed into pellets. The pellets were analyzed by IR,

and the IR spectra of the 5-ml extract is shown in Figure 6.

19. Plastiment in mortar could not be detected using thiA IR

method because of the low percentage transmission at the wavelengths for

identifying the carboxylate group. This low percentage transmission

resulted from the high amounts of dissolved constituents extracted from

the cement paste by the water. Results obtained indicated that the

admixture would have to be separated from the dissolved constituents, or

other solvents should be used to extract the Plastiment from the mortar.

20. Other solvents such as chloroform, carbon tetrachloride,

ethyl alcohol, acetone, dioxane, and acetonitrile were investigated for

extracting Plastiment from the mortar. A mortar specimen containing

Plastiment was ground, and 10-g portions were boiled in 100 mi of the

above-mentioned solvents. The solvent was removed by filtration and 10-mi

aliquots of each extract were placed on 0.40-g portions of KBr. The KBr

and extract were then dried overnight at 105 C and pellets made. The KBr

pellets were analyzed by IR, and the IR spectra obtained indicated that

Plastirnent was not being extracted with these solvents.

Thin-Layer Chromatography

21. TLC has been used to detect and quantitatively determine

certain carbohydrates including sugar and carboxylic acids in liquid 4 media. Segura and Gotto reported that they could detect as little as

0.1 µg of sugar by using TLC and fluorometric procedures. Bemiller5

also reported the separation and analysis of different carbohydrates.

11

Some of these TLC methods were investigated to determine whether carbo­

hydrates and salts of hydroxylated carboxylic-acid admixtures in concrete

could be detected~

22. Various TLC plates and solvents were investigated in order to

obtain good separation of sugar, corn syrup, and gluconates. Several

combinations of plates and solvents were used, and different detection

methods were tried, such as: sulfuric acid charring, iodine chamber,

Rhodamine B, 2' ,7' dichlorofluorescein, p-anisidine phthalate, tetra­

cyanoethylene, and bromthymol blue.

23. One of the better systems investigated was a stationary phase

of silica gel with a mobile phase of 9:4 ratio acetone:methanol. The

sucrose had an Rf of about 0.8; gluconic-acid salt did not migrate, and

corn syrup showed several good spots caused by the different carbo-

hydrates in it. Sulfuric acid charring at 200 C was found to be the

best method for detecting the carbohydrates on the silica-gel plate.

spotting several different concentrations of sucrose on the silica-gel

plate, the lowest amount that could be detected was 20 µg.

24. A 2-day-old mortar specimen containing sugar was extracted

with water. The water extract was then concentrated tenfold by evap­

oration on a steam bath. A silica-gel plate was spotted with 50 µi of

the extract and analyzed by the TLC procedure. There were no visible

evidences of sugar present. The same extract was tested by the alpha-

. --na-phthol--method and a-dark-viol-et ~--ol-or tl-evelopetl.

By

25. A more sensitive and quantitative TLC method by Segura and

Gotto4 was investigated. The thin-layer plates spotted with 10, 20, and

30 µg of sucrose were transferred to a sealed tank containing ammonium

hydrogen carbonate after the development with the solvent. The tank was

then placed inside an oven and heated to temperatures between 110 and

150 C for 2 hr. Fluorescent derivatives of the compound were formed,

and the fluorescent derivatives were measured on the plate using a

spectrofluorometer. A spectrofluorometer that could scan thin-layer

plates was not available; therefore, the sugar spots were removed from

the plates and placed into a liquid cell with methanol. The fluorescence

was then measured with a spectrofluorometer.

12

26. The standards, 10, 20, 30 µg, and a blank were measured, and

fluorescence units of 28, 31, 28, and 5, respectively, were obtained.

This method was not linear at the low ranges or accurate enough to be

considered for quantitative work. Acquiring or renting a scanning

spectrofluorometer which could scan thin-layer plates might be con­

sidered for further investigation.

High-Pressure Liquid Chromatography

27. HPLC is a relatively new technique for separation, identifi­

cation, and quantification of organic compounds. The possibilities of

HPLC as a method for detecting carbohydrates and salts of carboxylic­

acid admixtures in concrete were investigated. A liquid chromatograph

(LC) was obtained near the completion of the study; hence, only a limited

amount of work was accomplished using HPLC methods.

28. The LC was equipped with a fixed-wavelength UV detector and a

refractive index detector. A µ Bondapak c18 column was used for sepa­

ration, and distilled water buffered to a pH of 3 with phosphoric acid

was used as the mobile phase. The flow rate of the mobile phase was 0.5

m£/min. To establish whether the admixture could be detected and the

detection limit determined, standards of sucrose, Plastiment, and sodium

gluconate were prepared by dissolving the compounds in distilled water.

Mortar cubes containing the admixture were prepared as described in

paragraph 9. To determine whether the admixture could be detected in a

cementitious system, the mortar cubes were ground and a 10-g portion of

the ground mortar was extracted with boiling water. The extract was

neutralized by bubbling carbon dioxide gas through the extract until a

pH of 7 was obtained. Neutralization was required because alkaline

solutions will dissolve the siliceous column packing. The neutralized

extract was filtered through a 0.45-µm filter paper before being in­

jected into the LC.

29. Various concentrations of the standards were injected to

establish the retention times and the detection limit. The retention

times for sucrose and Plastiment were around 3 min, as shown in

13

Figures 7 and 8. The detection limits using the refractive index detec­

tor were approximately 50 µg/m£ for both compounds.

30. An extract from a mortar specimen containing Plastiment was

injected into the LC, operated using the same instrumental parameters as

for the standards. The peak area on the chromatogram was much greater

than expected since the extract only contained approximately 50 µg/ml

of Plastiment (Figure 9). This indicated an interference from other

dissolved constituents found in the extract.

31. The HPLC method investigated was found to be inadequate for

identifying carbohydrates and salts of carboxylic acids in concrete.

HPLC does show promise as a method for identifying water-soluble admix­

tures in concrete. Many other instrumental parameters, different columns,

and other solvents as mobile phases could be investigated. Other HPLC

techniques such as gel permeation and trace enrichment might be useful

for this type of separation and identification.

14

PART IV: CONCLUSION AND RECOMMENDATIONS

Conclusion

32. Different analytical methods for detecting, identifying,

and quantifying carbohydrates and salts of carboxylic acid admixtures

in concrete were investigated. Two published methods for detecting

sugar and an unpublished method for detecting both sugar and sodium

gluconate in concrete were investigated. Other methods investigated

included TLC, IR, and HPLC.

33. Sugar could be detected by both the published and unpublished

methods in young cement mortar. Sodium gluconate could also be detected

using the unpublished method. Quantitative measurements of sugar in

mortar were made using the unpublished method and by measuring color

intensity with a UV spectrophotometer. Mortar specimens containing a

known amount of sugar (0.05 percent) were analyzed using the unpublished

method and a UV spectrophotometer. The sugar content found in the

mortar decreased with increasing age and could not be detected after 7

days. These results indicate that the sugar had been converted to

another compound or compounds with age.

34. Most organic admixtures for concrete now being marketed can

be extracted from concrete and analyzed by IR methods; therefore, an IR

method was investigated for detecting salts or carooxyiii:: acius in

concrete. Standards were first analyzed, and the results indicated that

salts of carboxylic acids could be identified and quantified using IR.

Salts of carboxylic acids could not be detected in mortar specimens

using this IR method. The soluble constituents extracted from the

cement paste with the water interfered with the IR analysis. Since

interference was obtained from the water extract, six solvents were

evaluated for extracting the salts of carboxylic acid. None of the

solvents were found useful for extracting the admixture.

35. Several TLC methods were investigated for separating and

identifying the admixtures. One of the best TLC methods investigated

consisted of a stationary phase of silica gel with a mobile phase of

15

9:4 acetone:methanol, followed by charring with sulfuric acid. The

carbohydrates, sugar, and corn syrup could be separated and identified

using this method. This method was not sufficiently sensitive to detect

small amounts of carbohydrates present in concrete, and salts of car­

boxylic acid could not be separated using this method. A combination

TLC and fluorometric method for quantitative analysis of carbohydrates

was also investigated. It showed some promise but further investigation

is needed, and a scanning fluorometer would be needed.

36. A limited amount of work using an HPLC was done. The method

investigated was not successful in separating or identifying the ad­

mixtures in concrete. The detection limit using a refractive-index

detector was too high, and interference from the dissolved constituents

in the cement paste affected the results. HPLC shows promise as a

method and warrants further investigation.

Reconnnendations

37. Further investigation is needed if adequate methods for

identifying and measuring the amounts of carbohydrates and salts of

carboxylic-acid admixtures in concrete are to be developed. None of

the methods 'investigated during this st~dy would be considered satis­

factory. The two published methods for detecting sugar will detect

-sug-ar in concrete, -but -interference from other organic compounds is not

known, and test results have shown that sugar is converted to another

compound with age.

16

REFERENCES

1. U. S. Army Engineer Waterways Experiment Station, CE, Handbook for Concrete and Cement, with quarterly supplements, Vicksburg, Miss., Aug 1949.

2. Figg, J. W., Bowden, S. R., "The Analysis of Concrete," Her Majesty's Sationery Office, London, England, 1971.

3. Personal communication, Portland Cement Association, Skokie, Ill.

4. Segura, R., Gotto, A. M., "A New Fluorometric Procedure for the Detection and Quantitation of Organic Compounds in Thin-Layer Chromatography," Journal of Chromatography, Vol 99, 1974, pp 643-657.

5. Bemiller, J. N., "Qualitative Thin-Layer Chromatography," Methods in Carbohydrate Chemistry, Vol 6, Whistler and Bemiller, Editor, 1972.

17

Sample Mass

g Absorbance

10 0.42 20 0.56 30 0.85

Sample Massl g Absorbance

10 0.04 20 0.04 30 0.21

Table 1

Test Results for Sugar

2-Day Old Mortar

Concentration Sugar Found µg/m£

23.5 31.5 48.2

Table 2

Test Results for Sugar

4-Day Old Mortar

%

0.024 0.016 0.016

Concentration, Sugar Found µg/m£ %

-Z.l 0.002 2.1 0.001

11. 7 0.004

Actual Sugar Added

%

0.05 0.05 0.05

Actual Sugar Added

%

0.05 0.05 0.05

1 -- ~--- -

t -- - •

t--- ----- --- . I

~ I i l

I -t I

+-.: . -j

I

I ' - -+----

I I

- -- -i - --L--

- - l

Figure 1. Absorbance versus concentration for sugar standard

IC 11 12 13 14 15 16

Figure 2. Infrared spectra 500 µg of Plastiment

W .. UEN:....1.v.fH:.I(. CM'

2 5 7 10 11 12 13 16

Figure 3. Infrared spectra 1000 µg of Plastiment

w J... VfN'J.v,Bn~.- c~

"ooc 3000 2500 iOOO 1500 l•OO 130') 1200 1100 !(·00 ->oo BOO 700 650 62.!li

.,L: +' 1 ',_' '-·=r--1--1v L -f.CTT;r·i·r--r-~i; •;:••!i''''l'T. 1w11..!:!~T'-~l+1E~1cpn1JE1~fT''l'~r_:-r:rr•l"'~LTTfT:-icc.f'3=~1F"1_Tl'Co~l

]_~~- - i ----=----+----~--==~ -~{~+:~-;<~f __ i __ -f--__ -_; ___ ~-~.---:--:~~J- __ J ~-~~-t-L ! ,fT c~"~J -- - --1---- - -~.=:- 1-•=·c-'. • .. · ···!· .-•..... ·· .'.' .... -...•. ; .... -.·-··1 ... -.. -!'-'.·-. ·.'-.•-.c.-f.-.. -=Le •. · ... --.! - I t==F±-- l - 4-

- - - - - -- • - - - - -I - t . 1 1 -

- --:-1

. ~ +'

~ 5C >---->---t----+

~ ~

E-1 .:c :---·--+--+-----1~-----+'

" ~ ~ 30 ~---+-- ---+·

f :·:· f-~-

2 5 '

7

VIAVEH.1~CTH 1N .Y.!( PONS

10 11

Figure 4. Infrared spectra 1500 µg of Plastiment

12 13 1• 15 16

·~.--c- -+----1- _ __:__ _i_ ___ . ---··--·i-! t

l. l· I . !_____.._ ____ J

Figure 5. Absorbance versus concentration for Plastiment standard

iOCO

l 3\J ~-

1-f-

1.., i~ I '

IC f---

~s

I

"..000 r : . 1 j ·r ; i-- : L - , - ____ j_ ~~---__._._-----

I -

- l

=--=--le

10 11

WAHLENGTH IN MICRONS

Figure 6. Infrared spectra of mortar extract

12 13 14 15 16

~ ~=-~ -...:::.;:_.:..:::_ -·· _ __:.:__:. =-:....:.:..:. - - --_-_-_- -=---: '-----_-_-- ----=-~--=-:: _ _,__ _ _,_ ___ -M'----_--_-_--_-_ ~- -=~·=-:-: =-:~: =-·-__ -__:_. ~-~----1,_--+----1--+---lll----+----I--- -- - -·· - _.:....:.:.. = ~-=:--i-----+---t--t--+----tl---+_-__ -__ -__ -~ :_-:---~----I-=:_:_4=:.:...:.

-#-_,,

--t-- ----~:i=

Figure 7. Chromatogram of Plastiment standard

---- -1--

-- 1--

--

--

- --

--

- -- ~-

-- ----~-i----+---~i--::.:==+===~F-f~==--:=i:-~=-=--=i::-====--__ ~

-~

-I- -- . - -----·- ---- ~--

----- --------4

----- ,_ ----4 - . ·{

-- ------- ~---

_ _,-

··· - -1'

- -- .ti.

-- = -- ---

-f---

-- --- --4'-~

--

--~-

-{'U -- __ ._._ ·f----

'------- -

-- -+-

-- ·-t---·-- ._....... ~--

-I---

-- -

-- -· -

- I---

Figure 8. Chromatogram of sucrose standard

6---

.-j .... ·- - r-

---m ---m --

--

ID r.J;J·T-·---t---t

n--:- - -'D

lf)

---·-

. >­f •

"d' ---- --

--·- -

·--· -·-

--· ·-

--· -- ---·- -· >-

-1-----·

-- .. C-·

·->- r-.

---· >---

-· ---· -- --

--

----- - --

-~-

->-

r--

-

-r-------__ ,___ ----

-- r----

- --

·-

-·-·

Figure 9. Chromatogram of mortar extract

ln accordance with letter from DAEN-RDC, DAEN-ASI dated 22 July 1977, Subject: Facsimile Catalog Cards for Laboratory Technical Publications, a facsimile catalog card in Library of Congress MARC format is reproduced below.

Bean, Dennis L Investigation of methods for extraction, detection, and

identification of water-soluble admixtures in concrete / by Dennis L. Bean, Tony B. Husbands. Vicksburg, Miss. : U. S. Waterways Experiment Station ; Springfield, Va. : available from National Technical Information Service, 1978.

17, [10] p. : ill. ; 27 cm. (Miscellaneous paper - U. S. Army Engineer Waterways Experiment Station ; C-78-9)

Prepared for Assistant Secretary of the Army (R&D), Depart­ment of the Army, Wasiiington, D; C. , under" I'roj eet 4AO& 11 CHA9llL

References: p. 17.

1. Admixtures. 2. Concrete admixtures. I. Husbands, Tony Brooks, joint author. II. United States. Assistant Secre­tary of the Army (Research and Development). III. Series: United States. Waterways Experiment Station, Vicksburg, Miss. Miscellaneous paper ; C-78-9. TA7.W34m no.C-78-9