NATIONAL BUREAU OF STANDARDS REPORT

EVALUATION OF REFRACTORY QUALITIES OF

CONCRETES FOR JET AIRCRAFT WARM-UP, POWER CHECK,

MAINTENANCE APRONS, AND RUNWAYS

by

W. L. Pendergast, E. C. Tuma, D. K. Ward

7351

QUARTERLY REPORT

ON

U. S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS
THE NATIONAL BUREAU OF STANDARDS

Functions and Activities

The (unctions of the National Bureau of Standards are set forth in the Act of Congress, March 3, 1901, as amended by Congress in Public Law 619, 1950. These include the development and maintenance of the national standards of measurement and the provision of means and methods for making measurements consistent

with these standards; the determination of physical constants and properties of materials; the development of methods and instruments for testing materials, devices, and structures; advisory services to government agencies on scientific and technical problems; invention and development of devices to serve special needs of the Government; and the development of standard practices, codes, and specifications. The work includes basic

and applied research, development, engineering, instrumentation, testing, evaluation, calibration services,

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agencies when the work relates to and supplements the basic program of the Bureau or when the Bureau's

unique competence is required. The scope of activities is suggested by the listing of divisions and sections on the inside of the back cover.

Publications

The results of the Bureau’s research are published either in the Bureau’s own series of publications or

in the journals of professional and scientific societies. The Bureau itself publishes three periodicals avail- able from the Government Printing Office: The Journal of Research, published in four separate sections,

presents complete scientific and technical papers; the Technical News Bulletin presents summary and pre- liminary reports on work in progress; and Basic Radio Propagation Predictions provides data for determining

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and Technical Notes. A complete listing of the Bureau’s publications can be found in National Bureau of Standards Circular

460, Publications of the National Bureau of Standards, 1901 to June 1947 ($1.25), and the Supplement to National Bureau of Standards Circular 460, July 1947 to June 1957 ($1.50), and Miscellaneous Publication 240,

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NATIONAL BUREAU OF STANDARDS REPORT

NBS PROJECT MBS REPORT

1007-20-10472 October 12, 1961 7351

QUARTERLY REPORT

ON

EVALUATION OF REFRACTORY QUALITIES OF

CONCRETES FOR JET AIRCRAFT WARM-UP, POWER CHECK,

MAINTENANCE APRONS, AND RUNWAYS

by

W. L. Pendergast, E. C. Tuma, D. K. Ward

Inorganic Building Materials Section

Building Research Division

Sponsored by

Department of the Navy

Bureau of Yards and Docks

Reference: Task Y-F015 -15 -102

NBS File No. 10.7/10472

Approved

Bruce E„ Foster, Assistant Chief

Inorganic Building Materials Section

IMPORTANT. NOTICE

NATIONAL BUREAU Of ST

Intended for use within the

to additional evaluation and i listing of this Report, either

the Office of tho Director, Na

however, by the Government

to reproduce additional copR

Approved for public release by the

Director of the National Institute of

Standards and Technology (NIST) on October 9, 201 5.

urogress accounting documents

rmally published It Is subjected

reproduction, or open-literature

sion Is obtained In writing from Such permission Is not needed,

prepared If that agency wishes

U. S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS

QUARTERLY REPORT

ON

EVALUATION OF REFRACTORY QUALITIES OF

CONCRETES FOR JET AIRCRAFT WARM-UP, POWER CHECK,

MAINTENANCE APRONS, AND RUNWAYS

1. INTRODUCTION

The purpose of this project is the development of criteria for the

fabrication of jet exhaust resistant concretes. Concretes under development are evaluated by exposure to hot gases from a combustion chamber.

The combustion chamber delivers these gases at velocities and temperature

approaching field conditions.

2. ACTIVITIES

A Study of Concreting Materials and Concretes for Naval Facilities

Two sets of concrete test specimens were received during the period

covered by this report. One set of specimens was fabricated from the

mix used in placing power check facilities at the Naval Air Station,

Meridian, Mississippi, South East Naval District. Concrete containing

blast-furnace slag as the aggregate from Alabama and type I portland

cement was used at this installation. The second set of specimens was fabricated from the mix used at China Lake, Naval Ordnance Test Station,

Southwest Division, using expanded shale as the aggregate and a calcium

aluminate, Fondu, cement. The design and properties of the fresh concretes together with the 28-day flexural strength of these concretes A

appear in Table I. With the exception of the ratio of coarse to fine

aggregate of the expanded shale, coated, ("Rocklite") that was used in

power check facilities at China Lake, California, both met the requirements of NAVDOCKS Specification S-P16 Aircraft Power Check Facility.

Eleven jet impingement tests were completed on panels previously

submitted from the following power check facilities.

One panel, from the 12th Naval District, Naval Air Station at

Lemoore, California was tested after 42 days drying at 507,

relative humidity and 73°F. The spalling loss during the test was slight.

Three panels, from the 6th Naval District, Jacksonville, Florida

were tested after 42, 56, and 70 days drying respectively. The

panel tested after 42 days drying showed a slight loss during the

jet impingement test. Those tested, after or 70 days drying,

evidenced no loss.

Three panels, from the 5th Naval District, Marine Corps Air Station

at Cherry Point, North Carolina were tested after 42, 56, and 70

days drying. The three panels spalled considerably during jet

impingement.
'
Table I. Propertie of Fresh Concrete —

Ratio of Coarse Flexural

Identification

Type of AggregateType of — Admixture

Cement A. E. A.

to Fine

Aggregate

Cement Content

Ratio

w/c Slump

Air Content

Strength

28 days

oz/sack of ct. sack/yd"^ Inches % psl

5th Naval Dlst.

N. A. S. Norfolk, Va. TrapRock I Darex1.0 66:34 7 .435 1 to 2 6.2 750

8th Naval Dlst. N.A.A.S. Kingsville

Texas Basalt

Variety I Darex1.0 63:37 5.5 .58 2 5.0 650

8th Naval Dlst. N.A.A.S. Chasef leld Beeville, Texas Basalt

Variety I None 63:37 5.5 .61 1.5 2.0 655

11th Naval Dlst. M.C.A.S. El Toro California

Expanded

Shale

High

Alumina

Hydraulic None 67:33 6.5 .75 3. 25 4/ 600

13th Naval Dlst.

N.A. S. Whldbey Is. Oak Harbor, Wash.

Quarry

or Trap Rock II Darex —

0.75 63:28 6.5 .42 2.0 5.2 450

6th Naval Dlst.

N.A. S. Sanford

Florida

Blast- Furnace

Slag 1 Darex

1.0 58:42 7.5 .39 2.0 4 / 755

11th Naval Dlst, U.S.M.C.A.A.S.

Yuma, Arizona

Blast- Furnace

Slag II

Pozzollth

8AA 4.0 62:38 8.0 .43 3.0 7.7 704

6th Naval Dlst. U.S.M.C.A.A.S.

Beaufort, S. C. Trap

Rock I Aermix

1.75 57 :43 7.0 .43 3.25 5.5 7 20

6th Naval Dlst.

N.A. S. Glynco, Georgia

Trap

Rock 1 Darex

1.3 66:34 7.5 ,40 4/ 4/ 4/

5th Naval Dlst. M.C.A.S. Cherry Point, N. C, Trap

Rock I Darex

1.53 68:32 6.5 .46 2.5 6.4 650

6th Naval Dlst.

N.A. S, Jacksonville, Fla. Basalt

Variety I Darex

1.4 53:47 7.0 .43 1. 25 5.8 sio y

11th Naval Dlst.

N.A. S. Miramar, California

Expanded

Shale

High y

Alumina

Hydraulic

Air-ln

0.5 56:44 6.75 .60 2.0 5. 0-8.0 660

12th Naval Dlst. N.A.S. Lemoore, California

Southeast Division

N.A. S. Meridian, Miss.

Expanded

Shale

Blast- Furnace

Slag

II

I

Liquid

Plastair

2.75 FI. oz

Air-ln

1.50

. 47:53

59:41

7.5

7.0

.33

.53

^1 —1.25

2-

-1. 25

3-

1.75

4-

-1.00

5-

-1. 25

2. 0-3.0

4.1

3.2

3.2

4.1

3. 2

5. 0-8.0

6854/

695

625

635

765

Southwest Division

N.O. Test Station

China Lake, Calif.

Expanded

Shale

High y

Alumina

Hydraulic

Durair

1.25 66:34 6.75 .475 3.0 6.3 9/

1/ Data furnished by testing laboratories.

2/ Portland unless otherwise specified.

3/ Imported; Fondu

4/ Data not received even after repeated Inquiries.

5/ 0.25 oz. of Pozzollth per sack, also.

6/ Average of nine beams sawed from the panels submitted; as requested by Hr. P. P. Brown, Bureau of Yards and Docks, Washington 25, D. C„

7 / Domestic; Lumnlte.

8/ Power Check Station number.

9/ Data not received.
*
- 2 -

Three panels from the 11th Naval District, Naval Air Station,

Miramar, California were tested after but 6, 13, and 20 days

drying. These panels showed no spalling loss during the test.

One panel from the Southeastern Division, Naval Air Station at

Meridian, Mississippi, was tested, after 14 days drying, and showed

appreciable loss during the jet impingement test.

More complete data for the jet impingement tests are given in Table II.

The flexural strength of beams, approximately 18 x 6 x 6 inches cut

from each panel after completion of the jet impingement test was determined. The results of tests made on these beams cut from the edge of the

test area are given in Table II.

Previous reports have given data, on 18 x 6 x 6 inch beams cut from

the 18 x 18 x 6 inch test panels, that indicated the loss in flexural

strength could be attributed to heat treatment during the jet-blast test.

The effect of drying the specimen was not taken into consideration.

Further study of the data on this subject has led to the conclusion th&t

the drying shrinkage may be a greater factor affecting flexural strength

than the damage from the jetr-blast. A comparison of flexural strengths

determined on specimens cut from within the central test area with those

cut from the edge of the test area, and with those cut from panels similarly dried, but not subjected to the jet-blast, confirm these views.

It appears, therefore, that our data on the change in flexural strength

should be associated with loss in moisture due to drying. Table II

shows that the sensitivity of flexural strength to changes in moisture

differs widely for concretes containing different types of aggregate and

different types of cements. It is greater in concretes made with either

lightweight or blast-furnace slag aggregate and portland cement than when

dense aggregates are used. The use of high alumina cements with either

lightweight or blast-furnace slag accentuates this sensitivity. Table

III shows the flexural strength of these beams and beams soaked in water

for 48 hours before testing.

TABLE III. EFFECT OF JET IMPINGEMENT ON THE FLEXURAL STRENGTH OF CONCRETE BEAMS

Specimens iCut From

Power Check Outside Within

Facility Aggregate Cement Test Area Test Area

Beeville Diabase Portland I 459 494

Oak Harbor 1! Portland II 400 336

ft VI IV 414 400

Sanford Blast-furnace slag Portland I 384

460 I/ 190 I/ 275

1J 295

394

Cherry Point Diabase Portland I 490 460

Miramar Expanded shale High Alumina Hydraulic 170 150

If II IV 245 245

Meridian Blast-furnace slag Portland I 310 280 —^ Beams cut from outside test area and water soaked for 48 hours before testing.

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10/

Power

Check

Station

number.

11/

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not

received;

14

days

past

due.

-3-

Pressure Developed Within Concrete During Rapid Heating

Since we have been unable to detect pressure within concrete during

a jet impingement test of sufficient magnitude to account for spalling, we have been approaching it in another manner. During many jet-blast

tests, free moisture is forced out through the back of a six inch thickness

of concrete. An apparatus to determine the minimum steam pressure necessary to account for this phenomenon has been assembled and was mentioned

in N.B.S. Report 7197.

Photographs of this apparatus are shown in Figures 1 and 2. A line

drawing of the apparatus appeared in N.B.S. Report 7197 but further

instrumentation warrants including photographs in this report.

Cylinders, 6x6 inches, were fabricated using blast-furnace slag

aggregate or diabase aggregate with portland cement. The mixes used in

casting these cylinders were given in N.B.S. Report 6398 and N.B.S.

Report 6909 as P-BF-3 and P-Di-PH respectively. Two of the cylinders

fabricated with bl^ast-furnace slag were subjected to steam pressure after

having been moist cured for 28 days and dried for 20 or 21 days.

In the first test the base of the cylinder was exposed to 300 psi

pressure for five and one-half hours. No noticeable amount of water

appeared on the top face exposed to ambient temperature and pressure.

The second cylinder was exposed to similar conditions except that

heat was applied at the base of the cylinder mold (see Figure 1(6)) for

the purpose of keeping the water in a gaseous state. This resulted in

a rise in temperature of the base of the mold to 170°C during one and

one-half hours. The applied pressure during this part of the test

averaged 200 psi. Condensed steam was noticed covering an area of the

open surface of approximately one square inch. Water continued to emerge

from the top of the cylinder for an additional three hours, during which

time the pressure was kept constant at 285 psi, depositing sulphur and

other materials on the surface. This cylinder, after removal from the

mold, was broken. There was considerably more water apparent near the

top surface than near the bottom.

A third cylinder fabricated with the same concrete mix, blastfurnace slag aggregate and portland cement, but containing thermocouples

and pressure probe tubes (see Figure 1 (10) and (9) respectively)

positioned within the specimen, along the center axis and at one and

one-half inch spacings was tested.


Numbers indicate parts of apparatus shown in Figures 1 and 2

(1) Top enclosure for specimen; cold rolled steel; 1 1/2" plate

machined and recessed to fit cylindrical mold containing specimen.

(2) Specimen mold; 6" high duty steel pipe with top and bottom

ends machined to a plane surface; inside diameter trued to remove zinc

coating.

(3) Bottom enclosure recessed the same as (1) and an additional

recess to act as steam chamber.

(4)

(5)

(6)

Release valve, for condensed steam.

Steam inlet

Bunsen burner used to heat bottom of specimen holder

(7) Pressure control

(8) Pressure gauge on steam generator

(9) Pressure probe tubes

(10) Thermocouple leads

(ID Steam generator

(12) Thermometer well

(13) Safety Valve; blow off at 300 psi

(14) Pressure transducer

(15) Transducer balancing unit and power supply

(16) Rubber gaskets
FIG. 2

-4-

During this test, as in the two previous tests here reported, one face of the cylinder was open to the atmosphere while steam pressure was applied to the other. The pressure applied at the start of the test was

100 psi and increased to 300 psi over a period of 30 minutes. The first

temperature increase noted was 49 °C at 12 minutes, on the thermocouple (Figure 3) one and one-half inches from the face exposed to steam. The other two

thermocouples at distances of three and four and one-half inches from the

exposed face indicated no increase in temperature for 30 minutes. After

one hour thermocouples 1, 2, and 3 at one and one-half inches, three inches,

and four and one-half inches from the bottom face, indicated temperatures

of 99, 65, and 53°C respectively. Throughout tfce entire test, pressure

measurements in the specimen were taken only at probe tube #2 at the

middle of the specimen. Tube #1, one and one-half inches from the steam

face, was mechanically defective, causing a leakage at the place where

the tube entered the steel mold, and tube #3, four and one-half inches

from the steam face, showed no indication of pressure. After two hours

the pressure at the center of the specimen, as indicated by probe tube

#2, increased rapidly to approximately 50 psi and then gradually to 100

psi during the next three and one-half hours, at which time the test was discontinued. No moisture had appeared on the face of the specimen.

The following day the test was repeated on the same specimen with

somewhat different results (see Figure 4). Pressure of 100 psi was applied

to the bottom face of the cylinder immediately and increased to 300 psi in

35 minutes as it was in the first test. After one hour the pressure in

the test cylinder was less than ten psi. The pressure increase to 165

psi in approximately two hours, at which time the power to the autoclave

was cut off inadvertently. After a total of three and one-half hours

from the start of the test, the applied pressure had dropped to 165 psi

before the power was turned back on Apd heat applied at the base of the

mold. The pressure then increased to 320 psi in one-half hour and was adjusted at 300 psi throughout the remainder of the test. Near the

end of the test, the pressure at the center of the specimen, probe #2,

reached 240 psi.

Figure 4 shows the applied (generated) pressure and the resultant

pressure within the concrete at increasing periods of time. Temperatures

at the 3 inch level within the concrete are also shown. Data collected

during this second test, may not be truly indicative of concrete since

the first test may have effected the concrete or the mechanism controlling

the passage of water.

Effect of Drying on the Temperature Gradients, Measured in Concrete at

Increasing Depths From the Test Surface, During Jet Impingement Tests.

The following work was done to study the effect that the length of

the drying period, at 507> relative humidity and 73°F, had on the temperature gradients^

PRESSURE

lbs

/in.

RELATIONSHIP OF APPLIED STEAM PRESSURE TO

RESULTANT PRESSURE AND TEMPERATURES WITHIN

A CONCRETE CYLINDER.

FIG. 3

GENERATED PRESSURE, AUTOCLAVE

TEMPERATURE AT PROBE TUBE *2

PRESSURE PROBE TUBE **Z

150

125

100

75

50

25

0 Oo

0 1 2 3 4 5 6

150

125

100

75

50

25

0

TIME, HOURS

TEMPERATURE

-5-

Six concrete panels, 18 x 18 x 6 inches, were fabricated, three

using the concrete containing blast-furnace slag aggregate and portland

cement referred to before in this report and N.B.S. Report 6398. Three were fabricated using diabase aggregate and portland cement referred to

before in N.B.S. Report 6909. These panels were instrumented with three

multiple thermocouples at various locations in the concrete. Three of

the thermocouples were positioned at the surface of the panel, one at

the center of the test area, one three inches to the right of the center

and one three inches to the left. The remaining thermocouples were positioned at various depths directly below the surface. This arrangement

made possible the determination of temperatures at depths of one-quarter,

one-half, and 3/4 inches below the test surface. An additional thermocouple was placed at the one inch depth below the center of the test area. Data previously obtained at one-quarter and one-half inch depths below

the test surface was insufficient for our purpose.

Two of the blast-furnace slag-portland-cement panels were subjected

to the jet impingement test after 21 days moist curing, seven and 21 days

drying. The data collected on the panel dried for seven days appears in

Figure 5 and Table IV. Similar data for the panel dried for 21 days appears

in Figure 6 and Table V.

In comparing the data collected during the test of the first panel

with that of the second panel, the effect of placing the thermocouples

at the surface of the test panel is evident. The results of these tests

and the examination of the panels after test indicate that in the first

panel the surface thermocouples were slightly below the surface and in

the second panel the center surface thermocouple was slightly exposed.

When the multiple thermocouples are placed in the panel mold, before

casting, the three common leads are in tension. A misplacement of the

surface junction results in setting up errors of depth of the same magnitude for other junctions of the same multiple thermocouple.

The quarter inch spacings between junctionsj^of the chromel and alumel

wires were made with the use of a template or jig.

Due to an unavoidable error in the positioning of the surface thermocouples, data from tests of panels #1 and #2 are not wholly comparable.

However, the data shows that at, increasing periods of time, up to 20 minutes, at depths up to one inch, the temperature gradients decrease in

magnitude and approach constancy.

A cooling curve is included in Figure 6 for specimen 2 after 20

minute 'exposure to jet impingement. This data has not yet been evaluated. It may, however, be used to advantage in the study of heat transfer during cooling.

USCOMM-NBS -DC

Table

IV

Temperatures^

During

Jet

Impingement,

of

a

Concrete

Test

Panel

at

Three

Positions

on

the

Surface

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TEMPERATURE

FIG. 5 TEMPERATURE OF CONCRETE AS A FUNCTION OF DISTANCE FROM EXPOSED SURFACE DURING JET

IMPINGEMENT TEST, AT ONE MINUTES INTERVALS

TEMPERATURE

°F

FIG. 5 TEMPERATURE OF CONCRETE AS A FUNCTION OF DISTANCE FROM EXPOSED SURFACE DURING JET

IMPINGEMENT TEST, AT ONE MINUTES INTERVALS.

TEMPERATURE OF CONCRETE AS A FUNCTION OF DISTANCE FROM EXPOSED SURFACE DURING JET

IMPINGEMENT TEST, AT ONE MINUTES INTERVALS WITH COOLING CURVE ADDED.

U. S. DEPARTMENT OF COMMERCE

Luther H. Hodges, Secretary

NATIONAL BUREAU OF STANDARDS

A. V. Astin, Director

THE NATIONAL BUREAU OF STANDARDS

The scope of activities of the National Bureau of Standards at its major laboratories in Washington, D.C., and

Boulder, Colorado, is suggested in the following listing of the divisions and sections engaged in technical work.

In general, each section carries out specialized research, development, and engineering in the field indicated by

its title. A brief description of the activities, and of the resultant publications, appears on the inside of the

front cover. WASHINGTON, D.C.

Electricity. Resistance and Reactance. Electrochemistry. Electrical Instruments. Magnetic Measurements.

Dielectrics. Metrology. Photometry and Colorimetry. Refractometry. Photographic Research. Length. Engineering Metrology.

Mass and Scale. Volumetry and Densimetry.

Heat. Temperature Physics. Heat Measurements. Cryogenic Physics. Equation of State. Statistical Physics.

Radiation Physics. X-ray. Radioactivity. Radiation Theory. High Energy Radiation. Radiological Equipment.

Nucleonic Instrumentation. Neutron Physics.

Analytical and Inorganic Chemistry. Pure Substances. Spectrochemistry. Solution Chemistry. Standard Refer- ence Materials. Applied Analytical Research.

Mechanics. Sound. Pressure and Vacuum. Fluid Mechanics. Engineering Mechanics. Rheology. Combustion

Controls. Organic and Fibrous Materials. Rubber. Textiles. Paper. Leather. Testing and Specifications. Polymer Structure. Plastics. Dental Research.

Metallurgy. Thermal Metallurgy. Chemical Metallurgy. Mechanical Metallurgy. Corrosion. Metal Physics. Electrolysis and Metal Deposition.

Mineral Products. Engineering Ceramics. Class. Refractories. Enameled Metals. Crystal Growth. Physical

Properties. Constitution and Microstructure. Building Research. Structural Engineering. Fire Research. Mechanical Systems. Organic Building Materials. Codes and Safety Standards. Heat Transfer. Inorganic Building Materials. Applied Mathematics. Numerical Analysis. Computation. Statistical Engineering. Mathematical Physics, Operations Research. Data Processing Systems. Components and Techniques. Digital Circuitry. Digital Systems. Analog Systems.

Applications Engineering.

Atomic Physics. Spectroscopy. Infrared Spectroscopy, Solid State Physics. Electron Physics. Atomic Physics.

Instrumentation. Engineering Electronics. Electron Devices. Electronic Instrumentation. Mechanical Instru- ments. Basic Instrumentation. Physical Chemistry. Thermochemistry. Surface Chemistry. Organic Chemistry. Molecular Spectroscopy. Molecular Kinetics. Mass Spectrometry.

Office of Weights and Measures. BOULDER, COLO.

Cryogenic Engineering. Cryogenic Equipment. Cryogenic Processes. Properties of Materials. Cryogenic Technical Services. Ionosphere Research and Propagation. Low Frequency and Very Low Frequency Research. Ionosphere Research.

Prediction Services. Sun-Earth Relationships. Field Engineering. Radio Warning Services.

Radio Propagation Engineering. Data Reduction Instrumentation. Radio Noise. Tropospheric Measurements.

Tropospheric Analysis. Propagation-Terrain Effects. Radio-Meteorology. Lower Atmosphere Physics.

Radio Standards. High Frequency Electrical Standards. Radio Broadcast Service. Radio and Microwave Materials. Atomic Frequency and Time Interval Standards. Electronic Calibration Center. Millimeter-Wave Research.

Microwave Circuit Standards. Radio Systems. High Frequency and Very High Frequency Research. Modulation Research. Antenna Research.

Navigation Systems.

Upper Atmosphere and Space Physics. Upper Atmosphere and Plasma Physics. Ionosphere and Exosphere

Scatter. Airglow and Aurora. Ionospheric Radio Astronomy.
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