HIGH GRADEThe economical alternative to steel fibers and steel mesh.

Compressive strength 4

Flexural strength 5

Early shrinkage crack characteristics 6

Shrinkage characteristics 7

Water penetration capacity 8

Extraction characteristics 9

Fracture toughness and fracture energy 10

Sulphate resistance 11

Early strength 11

Fire resistance 12

Structural calculation 13

Application 14

Literature and sources 15

Advantages

The raw materialWe use pure polyolefine for our Fibrofor High Grade. This ensures absolute alkali resistance, not only on the surface. The fiber material is chemically neutral (inert) and rot-proof, and its water absorption rate is virtually 0%.

The fibrillated, bundled fibers and theiroptimal distributionDuring the sophisticated production process, special attention is paid to precise fibrillation of the fibers. The fibers are bundled and cut after the actual production process. Fibrillation and bundling allow optimal distribution throughout the concrete matrix.

The rough surfaceThe surface finish is deliberately selected to obtain a rough surface. This, among other things, also influences…

…the extraction characteristicsWe give high priority to the anchoring of our Fibrofor High Grade in the concrete. The rough-ness and fibrillation of the fibers greatly improve the extraction characteristics.

…the addition rate1 kg of Fibrofor High Grade per cubic metre willsuffice to obtain optimal concrete reinforcement. The feed rate can be individually matched to special applications.

The fibrillation

The fibrillated, bundled fibers

The roughness of the surface

The fibrils

Quality advance

2 / 3

The compressive strength is slightlyinfluenced by the addition of Fibrofor High Grade and produces a marginal change compared with base concrete. It lies within the range of other fiber concrete of a conventional type.

Average compressive strength after 28 days in N/mm2

Type of test specimen Concrete quality

Cube 150x150x150 mm

Compressive strength (N/mm2) 32 34 36

Plain concrete (without fibers)

With multifilament fibers

With Fibrofor High Grade

Type of test specimen Concrete quality

Bar 150x150x550mm*

Flexural strength (N/mm2)

Designation according to EN 206-1 C25/30 XC1/Dmax 32/CI 0.20/F3

Designation according to EN 206–1 C25/30 XC1/Dmax 32/CI 0.20/F3

Plain concrete (without fibers)

With multifilament fibers

With Fibrofor High Grade

3 4 5

Compressive strength

* Third-point testing

The addition of Fibrofor High Grade increases the flexural strength appreciably (up to 28%). This parameter is used for structural calcu-lations and is country-specific applied.

Average flexural strength after 28 days in N/mm2

Type of test specimen Concrete quality

Cube 150x150x150 mm

Compressive strength (N/mm2) 32 34 36

Plain concrete (without fibers)

With multifilament fibers

With Fibrofor High Grade

Type of test specimen Concrete quality

Bar 150x150x550mm*

Flexural strength (N/mm2)

Designation according to EN 206-1 C25/30 XC1/Dmax 32/CI 0.20/F3

Designation according to EN 206–1 C25/30 XC1/Dmax 32/CI 0.20/F3

Plain concrete (without fibers)

With multifilament fibers

With Fibrofor High Grade

3 4 5

Flexural strength

4 / 5

The significant parameter is deter-mined in a test series with 6 bending beams. The test specimens has a measurement of 150 x 150 x 550 mm (according to Fiber Concrete Guide-lines Austria) and will be charged in the third-point.

Total shrinkage crack lengths

Base concrete (without fibers)

Base concrete (without fibers)

with Fibrofor High Grade

with Fibrofor High Grade

1

2

1

2

Type of test specimenShrinkage ring: ø outside 590mm ø inside 290mm

Concrete gradeHigh-grade concrete C50 / 60

620mm

420mm

24mm

110mm

Testing of the early shrinkage crack characteristics by shrinkage ring is based on the most stringent test criteria. Investigations have shown that fiber concrete using Fibrofor High Grade will reduce shrinkage cracking by 85% compared with conventional

concrete types, which corresponds to quality class FS2. This means that fiber concrete using Fibrofor High Grade has a higher concrete density with minimum micro-cracks and that an earlier utilization of building structures can be expected.

Early shrinkage crack characteristics of fiber concrete class FS2 (testing time 5 hours)

Early shrinkage crack characteristics

Fibrofor High Grade is capable, among other things, of improving the shrinkage characteristics of the fresh concrete during the early setting phase. This is one of the crucial char-acteristics of High Grade fibers. In this case, the application of fibrillated High Grade fibers is advisable because its advantages allow concrete shrinkage to be minimised. Investigations have

shown that the addition of 1 kg ofFibrofor High Grade per cubic metre of concrete will allow values to be achieved which would otherwise require twice the amount of other fiber types. It must be noted, however, that such an increased fiber addition rate may appreciably reduce the compressive strength.

1

300

200

100

20 3

0

4 5 6 7 8

Shr

inka

ge

crac

king

(µ)

Time in days (t)

1 20 3 4 5 6 7 8

Time in days (t)

Shr

inka

ge

crac

king

(µ)

300

200

100

0

300

200

100

0

Plain concrete Fibrofor High Grade

1

300

200

100

20 3

0

4 5 6 7 8

Shr

inka

ge

crac

king

(µ)

Time in days (t)

1 20 3 4 5 6 7 8

Time in days (t)

Shr

inka

ge

crac

king

(µ)

300

200

100

0

300

200

100

0

Fiber concrete

Fiber concrete with Fibrofor High Grade and plain concrete, fiber addition rate 1kg /m3

Fiber concrete with conventional, fibrillated fibers and plain concrete, fiber addition rate 1.8 kg/m3

Shrinkage characteristics

6 / 7

Plain concrete

Fibrofor High Grade reduce the waterpenetration depth in the concrete body. The test specimen was based on a concrete formulation with aggregates 0/16, 350kg/m3 CEM I 32.5 plus 0.9% plasticiser. The water-to-cement factor was 0.38. The compressive strength determined was 59.3N/mm2 for base concrete and 66.2N/mm2 for fiber concrete us-ing Fibrofor High Grade (test pressure 0.8 MPa).

Type of test specimen Water penetration depthCube 150x150x150 mm

Plain concrete (without fibers) 2.20 cm

with Fibrofor High Grade 1 kg/m3 1.75 cm

The chart shows that the water penetration depth will be reduced by over 25% when Fibrofor High Grade is added.

Water penetration capacity

The reinforcement fibers must be embedded and anchored in the concrete matrix so that the positive fiber characteristics will be retained under structural loading. Monofila-ment fibers with a smooth surface offer this characteristic only to a certain extent. On the other hand, this is one of the very areas where the special design features and the better technical

values of Fibrofor High Grade have their full effect. Extensive scientific investigations show that Fibrofor High Grade offers optimal extraction strength and extraction characteristics. The figures show the directions of the force and the distribution of the forces under tensile stressing and illustrate the benefits of fibrillated High Grade fibers.

Extraction characteristics

Fibrofor High Grade

Monofilament fiber

8 / 9

Fracture toughness andfracture energy

Fiber concrete has a very good fracturetoughness. Investigations have shown the fracture energy of concrete using Fibrofor High Grade to increase by as much as 240%. As a result, cracking of the concrete – which is a very brittle construction material – due to soil movements can be minimized.

at an age of

Plain concrete (without fibers)

with multifilament fibers

with Fibrofor High Grade

0.56 J

1.26 J

1.89 J

0.90 J

1.81 J

2.80 J

1.04 J

2.11 J

3.58 J

3 days 7 days 28 days

Type of test specimenCube 150x150x150 mm

Fracture energy (up to fracture)of the equivalent flexural tensile strength test

Sulphate resistance /Early strength

Sulphate resistanceWhen used in conjunction with sulphatecontaining substances, concrete reinforced with Fibrofor High Grade offers better technical parameters than other fiber concrete types. Its advantage over plain concrete is even substantial.

Early strengthJust like conventional fiber concrete,concrete reinforced with Fibrofor HighGrade also has an increased early strength. This advantage can be economically exploited especially in slip-forming applications and in the prefabrication industry as well as otherwise in concrete construction applications.

Plain concrete (without fibers)

with multifilament fibers

with Fibrofor High Grade

Solution I Solution II

5.84 100 %

6.40 110 %

7.24 124%

* 4.24 73%

6.04 103%

6.45 110%

4.44 76 %

6.47 111%

6.52 112%

Solution III

Type of test specimen40 x 40 x 160mm

Average flexural tensile strengths N/mm2 measured after the following baths on air-dry specimen

No. of the test specimen

Plain concrete (without fibers)

with multifilament fibers

with Fibrofor High Grade

1 2 3

3.8

4.6

4.7

3.7

4.6

4.9

3.8

4.5

4.6

3.8

4.6

4.6

Type of test specimenCube 150x150x150mm

24-hour compressivestrength (N/mm2)

Meanvalue

Sulphate resistance

Early strength

* This value (100%) is used as the basis for comparing the other equivalent flexural tensile strength values.

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Fire resistance

In the event of fire, due to the rapidly rising temperatures, such high stresses arise that it is not possible for conventional concrete to withstand this vapor pressure. Spalling and even the breakdown of the construction can be the consequence.

With the addition of about 2 kg/m3

Fibrofor High Grade the concrete has a higher permeability. In the event of a fire the melting point of approx. 160°C causes the fibers to melt. The result is a capillary network in the concrete and the water vapor that is produced can escape.

12 / 13

Structural calculation

Structural calculations according to EC 2 prove that with the use of Fibrofor High Grade various structural elements do not need any more conventional steel or steel mesh reinforcements. It is also possible to significantly reduce the steel reinforcement requirement by combining reinforce-ment components (Fibrofor High Grade and steel).

Proven reductions of construction steel offer extremely interesting cost savings for our customers.We would be pleased to present you an alternative to conventionally reinforced concrete for your building project. Our civil engineers calculate using a state-of-the-art dimensioning software based on finite element.

Application

Industrial floorsDomestic buildings

Pavement in concrete Retaining wallsConcrete walls

Power stationsBridge construction

Waste water treatment plant

Prefabrication industryShotcrete

cycling tracks

Compressive strength, equivalent flexural tensilestrength, fracture toughness and fracture energy,sulphate resistance, early strength, early shrink-age crack characteristicsConstruction industry engineering approval EMI AG,Budapest, Hungary

Equivalent flexural tensile strengthVersuchs- und Forschungsanstalt, MA39,Vienna, Austria

Shrinkage characteristicsZollo Report "Hardened Concrete Drying Shrinkage",Prof. Dr. Zollo, ACI, Detroit, USA

Fire resistanceFire load in the test facility of Hagerbach AG, Sargans

Investigation report MPADortmund, Germany

Fiber concrete guidelinesAustrian Association for Concrete and Civil Engineering, Vienna, Austria

Flexural strength and compressive strengthTest certification by Dr. Hartl GesmbH., stateaccredited test institution, Seyring, Austria

Water penetration depthAkademia Rolnicza, Poznan, Poland

Literature and sources

14 / 15

Contact us.

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013

Brugg Contec AGAachstrasse 11CH-8590 RomanshornT +41 71 466 12 12F +41 71 466 12 10info@bruggcontec.comwww.bruggcontec.com