effects of thermal load to the mechanical … · effects of thermal load to the mechanical...

EFFECTS OF THERMAL LOAD TO THE

MECHANICAL PROPERTIES OF POLYMER CONCRETE

ORSOLYA ILONA NÉMETH S U P E R V I S O R S : GYÖRGY F A R K A S ÉVA LUBLÓY

B U D A P E S T U N I V E R S I T Y O F T E C H N O L O G Y A N D

E C O N O M I C S D E P A R T M E N T O F S T R U C T U R A L E N G I N E E R I N G

9th fib International PhD symposium in Civil Engineering, July 22nd – July 25th 2012, Karlsruhe, Germany

Cement/polymer

2012.07.24.

Polymer concretes have good strength characteristics, dense structure, slight moisture absorption, high chemical and physical resistivity , rapid solidification.

NO water, NO cement!!!

Cement concrete

Portland cement

Water Aggregates

Admixtures

Polymer concrete

Polymer binder

Aggregates

Admixtures

9th fib International PhD Symposium in Civil Engineering

Material composition

2012.07.24.

Binder: POLIMAL 144-1 16w%

Catalyst: Trigonox 44B Initiator: Co-1 Cobalt

Quarz gravel 2-4 mm 38w%

Quarz sand 0-2 mm 38w%

Calcium-Carbonate 5w%


Polymer concrete vs. temperature

2012.07.24.

Thanks to the polymer component, the mechanical properties and possible applications of polymer concretes are essentially influenced by the change of temperature and the load caused by fire.

In general, high temperature results degradation and finally, loss of strength of the polymers.


The goal

2012.07.24.

Determine the behaviors of the polymer concrete of given composition under thermal load.

Defines the residual values of

compression strength

flexural strength

modulus of elasticity

after exposed high temperature.


Derivatograph Q-1500 D

Preliminary experiment

Derivatographic measurement is a simultaneous thermo-analytical method which simultaneously produces thermo-gravimetric (TG), differential thermo-analysis (DTA) and derivative thermo-gravimetric ( DTG) signs from a small amount of the material.

2012.07.24. 9th fib International PhD Symposium in Civil Engineering

The process

2012.07.24.

A small amount of polymer concrete...

After crushing…

Put in the measurement equipment and ignite on high temperature

The changes in the mass of the sample (TG curve) were measured!


Derivatogram of the UP polymer concrete

2012.07.24.

Thermo-gravimetric curve

Temperature


400 °C !

During the 400°C heat load the specimens caught fire without any lighting effect and …


…continued to burn freely until they got carbonized.

In the case of concrete with plastic binder, the burning of the plastic provides enough energy for the continuation of burning.


Compression strength Flexural strength

2012.07.24.

The specimens

150 x 150 x 150 mm cubes 3-3 pieces in all heat step

performed on the basis of the MSZ EN 12 390-3:2009 Standard

70 x 70 x 250 mm beams 3-3 pieces in all heat step

performed on the basis of the MSZ EN 12 390-5:2009 Standard


The heat stages

During the tests, the polymer concrete specimens of given composition were subjected to load in four stages:

20°C,

100°C,

200°C,

300°C

Testing without any direct flame effect!

2012.07.24.

100 °C 200 °C

300 °C


Inner layer

The inner layer was not discoloured during the two-hour heat load


After the experimens…


Relative residual compression strength

2012.07.24.

0

0,2

0,4

0,6

0,8

1

1,2

0 200 400 600 800 1000

f cT/f

c2

0°C

Temperature (°C)

Mix1

Mix2

UP polymer concrete

98.7 N/mm2 93,6 N/mm2


Conclusions of the compression strength test

2012.07.24.

• the extent of the strength reduction of polymer concrete does not exceed the strength reduction of concrete of the same strength, up to a heat load of 300°C; • in the case of concrete of a lower strength (Mix1), the extent of strength reduction was higher than in the case of polymer concrete; • BUT: over 300°C the UP polymer concrete started to burn and continued to burn freely until the specimens got carbonized, practically until their strength was considered to be 0 N/mm2


Relative residual flexural strength

2012.07.24.

0

0,2

0,4

0,6

0,8

1

1,2

0 200 400 600 800 1000

f flT

/ffl

20°C

Temperature (°C)

Mix1

UP polymer concrete

28,5 N/mm2

17,6 N/mm2


Conclusions of the flexural strength test

2012.07.24.

• the extent of the flexural strength reduction of polymer concrete is higher than the extent of compressive strength reduction; • the extent of the flexural strength reduction of polymer concrete exceeds, up to a head load of 300°C, the strength reduction of concrete.


Modulus of elasticity

2012.07.24.

0

10

20

30

40

50

60

70

80

90

100

0 100 200

Fo

rc

e (

kN

)

Displacement (µm)

typical force – displacement curve


The residual values of the modulus of elasticity depend on temperature

2012.07.24.

0

0,2

0,4

0,6

0,8

1

1,2

0 100 200 300 400

Ec

T/E

c2

0°C

Temperature (°C)

UP polymer concrete

19446 N/mm2

9861 N/mm2


Summary This study examined the effect of high temperatures on UP polymer concrete. Experiments were conducted to detect the behaviour of UP polymer concrete at 4 different temperatures.

the extent of the strength reduction of polymer concrete does not exceed, up to a heat load of 300°C, the strength reduction of concrete of the same strength;

the tendency of the extent of the flexural strength reduction of polymer concrete and the extent of the modulus of elasticity reduction of polymer concrete are similar, but they show more significant decrease up to a head load of 300°C.

In continue:

The UP polymer concrete had no fire resistance. Our future research will be extended in this direction.


A C K N O W L E D G E M E N T S

T H E W O R K R E P O R T E D I N T H E P A P E R H A S B E E N D E V E L O P E D I N T H E F R A M E W O R K O F T H E P R O J E C T „TALENT C A R E A N D C U L T I V A T I O N I N T H E S C I E N T I F I C W O R K S H O P S O F B M E " P R O J E C T . T H I S P R O J E C T I S S U P P O R T E D B Y T H E G R A N T TÁMOP -4 . 2 . 2 . B - 1 0 / 1 - - 2 0 1 0 - 0 0 0 9 .

2012.07.24.

Thank you for kind attention!


effects of thermal load to the mechanical … · effects of thermal load to the mechanical...

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