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    STEEL FIBRE REINFORCED CONTINUOUS COMPOSITE SLABS

    Florian P. AckermannKaiserslautern University of Technology

    Institute of Concrete Structures and Structural DesignKaiserslautern, Germany

    [email protected]

    J rgen SchnellKaiserslautern University of Technology

    Institute of Concrete Structures and Structural Design

    Kaiserslautern, [email protected]

    ABSTRACT

    The paper deals with composite slabs using steel fibre reinforced concrete as topping. The aimof a research project of the Kaiserslautern University of Technology is the evaluation of designrecommendations for steel fibre reinforced composite slabs. The constructive as well as thestructural conventional reinforcement are substituted completely by the use of steel fibres. Themain focus of a first test series was to research the possible rotation capacity of steel fibrereinforced composite slabs in the region of negative bending. In a second test series, four fullscale tests on continuous composite slabs were accomplished.

    INTRODUCTION

    Nowadays, the use of steel composite floors in buildings is common practice. Conventionalsteel composite floors have proved themselves as an extremely cost-effective floor system fordomestic, commercial or industrial buildings. Significant advantages arise from the lowconstruction costs and especially from the benefit of saving time during the building process.Researches in innovative composite slabs with steel fibre reinforced concrete topping are inprogress at the Kaiserslautern University of Technology. Different types of slabs with varied

    geometries are selected for the tests. Special attention should be paid to the redistribution ofbending moments from the support to the field. The conventional reinforcement is completelysubstituted by the steel fibres. Thus, for continuous composite floors an even more efficient andmore economic slab system can be achieved.

    Steel composite slabs are load bearing members, which consist of steel sheeting and aconcrete topping. In the construction process, the steel sheeting will be placed by hands. Afterfixing, it is available as a working platform that provides a safety screen at the same time.During the concreting, the sheeting acts as a shuttering. Thus, a quick and a space-saving

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    progress of construction work can be achieved. In composite building construction theapplication of steel sheets as long as possible and therewith the utilization of continuouslyworking composite floor slabs has been proved to be an outstanding productive constructionmethod [Bode 1998].

    In Germany, the design of steel decking and composite slabs is regulated by DIN 18800-5:2007

    [DIN 18800-5 2007]. Following this guideline continuously running composite slabs may beanalysed using linear elastic methods with and without moment redistribution (up to 30 %). Rigidplastic global analysis is feasible presuming it can be shown that sections where plasticrotations are required have sufficient rotation capacity. Rigid plastic global analysis without acheck of the sufficient rotation capacity is tolerable only in case of usage of re-entrant steelsheeting and of reinforcement with a high ductility and in case of a maximum span of 6 meters.Continuous slab systems can be analysed by approximation as a series of simply supportedbeams; in doing so a nominal reinforcement of 0.2 percent of the concrete cross-section areahas to be arranged for crack control at the supports. For slabs that are propped during placingthe concrete, a nominal reinforcement of 0.4 percent is required.

    According to [DIN 18800-5 2007] the concrete topping has always to be proved with a nominalreinforcement of 0.8 cm/m in both directions. This reinforcement may be imputed to the

    calculated reinforcement required structural bending. Usually, the steel sheets are installed overseveral spans. No joints are arranged in the concrete topping and therefore the floor behavesas a continuous slab system and negative bending will occur over the inner supports. Hence, forall composite slabs an additional reinforcement has to be built in. The aim of the researchproject is to substitute the constructive as well as the structural reinforcement by the use of steelfibre reinforced concrete.

    STEEL FIBRE REINFORCED CONCRETE

    The application of fibres as an additive in order to advance the ductility of the concrete has gotits origins in the ancient times. Animal hairs and straw fibres were used in order to enhance thematerial properties of adobes. The idea to improve the material properties of concrete by fibre

    admixture doesnt reach back so far. The first patent for the application of steel fibres wasgranted in 1874. However, the researches in the field of steel fibre reinforced concrete havebeen started substantially later (since 1960).

    In Germany, no standard for the design of steel fibre reinforced concrete exist. Its appliance isregulated by technical approvals or by approval in individual cases only. The German Societyfor Concrete and Construction Technology (DBV) has published a technical bulletin concerningthe design of steel fibre reinforced concrete [DBV 2001], which does not provide an officiallycodified standard yet. According to this bulletin, steel fibre reinforced concrete is defined as aconcrete corresponding to [DIN 1045-1 2001] which is provided with steel fibres in order toachieve specific attributes. In order to resolve the drawback that no codified standard exists toregulate the steel fibre reinforced material, the German Committee for Structural Concrete

    (DAfStb) has decided to issue a new guideline [DAfStb 2005]. This document corresponds tothe regular concrete standard [DIN 1045-1 2001] and supplements it with the additionalregulations for steel fibre reinforced concrete. But at present the guideline is not complete yet (itis located in the 23. draft). Nevertheless, in the course of this year the decision of its transfer tothe approval procedure is planned.

    Until now, industrial ground floor slabs constitute the main field of application of the steel fibrereinforced concrete. In Germany, 25 percent of the manufactured ground floor slabs are madeof this material [Falkner and Teutsch 2006]. In the past years, this material shows a favourabletrend, the matter of fact of which is reflected in the application for domestic construction, too.

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    Here, floor slabs and cellar walls represent the main field of the application. Primary, thesubstitution of the constructive reinforcement is the main focus. A large number of tests haveshown that a complete substitution of the structurally required reinforcement is impossible. Theaddition of fibres with volume ratios that are common in practice does not increase theresistance capacity significantly. Solely the manipulation of the post fracture behaviour and as aresult the improvement of the ductility stands to the fore.

    Significant advantages by the use of steel fibre reinforced concrete are:

    Considerable simplification of the construction process Omission of the installation, the control and the acceptance procedure of the

    reinforcement Omission of the reinforcement detailing drawings Avoiding of failures by reinforcement as far as possible Improvement of the crack behaviour and so a significant lower scatter of the tensile

    strength Enhancement of the impact strength (up to 25 times) and of the fatigue strength Less spalling at the borders and corners, because the fibres are effective close to

    surface as well

    Tying of cracks and thereby transfer of forces across the cracksThe vision of some planners that steel fibre reinforced concrete will substitute the normalconcrete totally has to be invalidated. It will never be likely to displace the normal concrete.Quite the contrary, steel fibre reinforced concrete can be integrated between the reinforcedconcrete and the unreinforced one. In the uncracked state the fibres do not effect a significantmodification of the resistance capacity, because their volume ratio constitutes only a small partof the entire volume. The addition of steel fibres effects only a marginal enhancement ofcompression strength. Solely, the behaviour after crushing shows an appreciable changing.With increasing fibre ratio, the ductility is progressing. In tension, the behaviour depends on thefibre ratio. The more fibres are admixed, the merrier is the load bearing behaviour aftercracking. If the fibre ratio is conforming to the critical fibre volume Vcrit, the full load can becarried by the cracked cross section. Is the volume higher than the critical volume, the actual

    load can be increased after cracking.

    For members the design of which is in accordance with [DBV 2001] or [DAfStb 2005], a firmcondition of equilibrium has to be reached after cracking of the cross section. In staticallydeterminated systems, this demand is not possible with fibre volumes that are common inpractice. It becomes apparent that pure steel fibre reinforced concrete can substitute theconventional reinforcement only in statically indeterminated systems or in staticallydeterminated systems with a permanent normal compressive force as a result of an extraneouscause.

    Within the research project on steel fibre reinforced continuous composite floors, the applicationof steel fibre reinforced concrete as a load bearing element is possible, because the possibilityof a redistribution of the stress resultants after cracking is given. The ductile behaviour of steel

    fibre reinforced concrete affected by a multiple crack pattern allows a large rotation and thus theprecondition of redistribution.

    The use of steel fibre reinforced concrete as a load bearing element call for considerationsconcerning a raised security level. The investigated composite slab systems possess anadequate redundancy. In case of bad workmanship (e.g. undersized fibre content or worstcase no fibre content over the intermediate support) a series of simply supported beamsemerges and the steel sheeting keeps the slab in position.

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    STEEL FIBRE REINFORCED COMPOSITE SLABS

    Based on researches described in [Sauerborn 1995], [Droese and Riese 1996] and [Riese2006] steel fibre reinforced continuous composite slabs are investigated at KaiserslauternUniversity of Technology. Aim of the research project is the evaluation of designrecommendations for steel fibre reinforced composite slabs. No conventional steel

    reinforcement (bars or mesh) have been built in: the hogging bending moment is only carried bythe steel fibre reinforced concrete. This innovative slab system comprises an enormouspotential for savings. Its outstanding beneficial characteristics are:

    Profile sheetingo acts as stay-in-place formworko constitutes bottom reinforcement for the slabo offers an immediate working platform and protects workers belowo supports loads during construction

    Labour intensive steel fixing, reinforcement drawings and the reinforcement acceptanceprocedure can be omitted

    Enormous time saving in building process Due to its low weight the sheets can be placed by hand without using any crane

    Lower stock requirements needed Less deflection due to the continuous bending effect will occur For the complete system savings in the range of 10 percent of the total costs are

    predicted [Gossla and Pepin 2004]

    In the area of negative bending moments, the structural analysis is carried out in analogy to anormal concrete slab. The upper face of the slab is tensioned and at the bottom side thecompression zone is located, which has a more or less comb-shaped form as a result of thegeometry of sheeting. The steel sheet section may account for the structural analysis, if it runscontinuously over the intermediate support. In case of a joint or an overlapping, the resistanceof the steel sheet section may not be taken into account. This effect was found by Stark andBrekelmans during their researches, too [Stark and Brekelmans 1996]. Particularly in case of apoor reinforcement ratio of the hogging area what is common in case of plain steel fibrereinforced concrete or in case of a larger sheet thickness, the load bearing capacity of thesheet is respectable.

    In the area of negative bending, the depth of the compression zone as a result of the humblereinforcement ratio is very small. The plastic neutral axis is located very deep in the sheeting,which therefore is related with a small compressive force only. Correspondingly, the forces thathave to be carried over the composite joint are small, too. Already sheets with a very badcomposite behaviour achieve a full dowelling ratio at the support.

    According to [DIN 18800-5 2007] the moment resistance of a continuous composite slab at thesupport can be analysed with a perfect plastic stress distribution. This proposed distribution wasmodified for the analysis of steel fibre reinforced composite slabs. The tensile resistance of thesteel fibre reinforced concrete is considered by a stress block, too. For the determination of the

    tensile properties, material tests on steel fibre reinforced concrete beams according to [DBV2001] were carried out and evaluated. Figure 1 displays the miscellaneous bearing ratios, whichare accounted for the evaluation of the plastic moment resistance. The location of the plasticneutral axis has to be estimated by an iterative procedure as long as the equilibrium condition(1) is fulfilled.

    c pc pt F(N N ) N N 0 + + + = (1)

    Then the full plastic moment resistance is calculated according to equation (2).

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    pc pc c cpt ptpl F FM N z N z N z N z= + (2)

    h zpl +

    -

    +

    -

    Npt

    Npc Nc

    NF

    fyp

    fyp

    kccc fc

    sys ct feq,ct,II

    zc

    zF

    zpc

    zpt Mpl

    Fig. 1 determination of the full plastic moment resistance for negative bending

    with: Nc: compression force in the steel fibre reinforced concrete

    Npc: compression force in the sheeting

    Npt: tensile force in the sheeting

    NF: tensile force in the steel fibre reinforced concrete

    ci: factor for long-term behaviour

    sys: scaling factor

    kc: factor for the use of a stress block

    Table 1 displays both, the measured maximum hogging moment values and the previouslycalculated plastic moments. The calculated values correspond relatively well with the reachedtest values. Here, the bearing capacity of the sheet was taking into account.

    max MTest Mpl,calc.

    [kNm/m] [kNm/m]

    S1_SHR_51_V1 -23,4 -23,3S1_SHR_51_V2 -20,0 -21,5

    S1_HODY_V1 -19,5 -19,9S1_HODY_V2 -23,4 -19,6

    S1_SHR_51_V3 -23,9 -24,8

    S2_SHR_51_V1 -25,3 -26,5S2_SHR_51_V2 -22,4 -20,6S2_HODY_V1 -20,4 -21,8S2_HODY_V2 -17,7 -19,8

    specimen

    Table 1 hogging moment test results and previously calculated values

    TEST PROGRAM

    Test series and specimenUntil now, two different test series were carried out. In the first tests series, the possible rotationat the middle support of a two-span composite slab was investigated. Therefore, only the areaof the hogging moment was simulated and tested. In the second test series, four full scale testson continuous composite slabs were carried out. For all tests of the first two series, two differentcross sections were used (see Figure 2).

    In the meantime, several different types of steel sheeting exist for the construction purposes.According to their geometry they can be separated into two main categories: the re-entrant

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    (dovetail) profiles with or without indentations and the trapezoidal profiles with web indentationsor embossments.

    Fig. 2 cross sections of the test specimens (left: HOLORIB SHR51 sheet, right: HODY sheet)

    A sufficient composite action between the sheet and the concrete topping has to be guaranteed.For testing sheets of both categories were used. As a typical representative for the re-entrantgeometry the SUPER HOLORIB SHR 51 sheet was used (see. Figure 2 left), as typicalrepresentative for the trapezoidal geometry the HODY sheet was built in (see Figure 2 right). Allspecimens were fully supported during casting. This is the most unfavourable case for thecomposite joint, because it has to cope with the dead loads as well. Both lateral edges of thesheeting were enclosed with concrete flanges in order to avoid a separating of the sheeting andthe concrete topping. So, the full participation on the load bearing of the sheeting can be

    guaranteed over the entire width. Table 2 gives an overview over the specimen and dimensionsof the first and second test series.

    length L width height

    [mm] [mm] [mm]

    S1_SHR_51_V1 2000 700 160

    S1_SHR_51_V2 2000 700 160S1_HODY_V1 2000 700 160S1_HODY_V2 2000 700 160

    S1_SHR_51_V3 2000 700 160

    S2_SHR_51_V1 6000 700 160

    S2_SHR_51_V2 6000 700 160S2_HODY_V1 6000 700 160S2_HODY_V2 6000 700 160

    specimen

    two-span

    single-span

    system

    g

    P

    L

    P/2 P /2P/2 P /2

    g

    L

    Table 2 test specimen of series #1 and #2

    Series #1

    The test setup of series #1 is shown in Figure 3. The span of the slab was 2.00 meters, thewidth 70 centimetres and the slab depth 16 centimetres (sections see Figure 2). In the middle ofthe span, the load was linearly set up by an hydraulic jack. It was increased by imposing smallload steps up to the failure load. The tests were carried out with displacement control so that asmuch information as possible could be recorded on the support behaviour. The loads at thecrossheads were measured with load cells. The displacements and the end-slip were recordedwith displacement traducers. In the middle and in the quarters of the span, strain gauges wereapplied to the top and the bottom of the steel sheeting. The strain at the surface of the concreteslab was recorded with strain-measuring points. Further information and details about series #1can be gleaned from [Ackermann and Schnell 2007].

    Series #2

    In a second test series, four tests on continuous composite slabs were carried out. The setup isshown in Figure 4. Both spans of the slab were 3.00 meters, the width 70 centimetres and theslab depth 16 centimetres (sections see Figure 2). In the third points of the span, the load waslinearly set up by hydraulic jacks. It was increased in small load steps up to the failure load.

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    Fig. 3 test setup - series #1

    Fig. 4 test setup - series #2

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    The loads at the crossheads were measured with load cells. Under the middle support, thereactions were recorded with two load cells. The slab was built up as a simple span slab.Afterwards, the crossheads and the load introduction construction were arranged. In a first step,the middle support was lifted up by spindles until the hogging moment has a value of a hoggingmoment produced of dead load and superstructural parts. Then, the test was started. Thedisplacements and the end-slip were recorded with displacement traducers. At the middle

    support and at the load introduction points, strain gauges were applied to the top and thebottom of the steel sheeting. The strain at the surface and on the side of the concrete slab wasrecorded with strain-measuring points. In order to achieve a predefined shear introductionlength, crack inductors were built in under the outmost load introduction points.

    Steel fi bre reinfo rced concrete (SFRC)

    For the first two series, different steel fibre reinforced concrete mixtures were used. In series #1,concrete with a fibre content of 100 kg per cubic meter (or 1.27 Vol. %) was mixed. Thecorrugated ARCELOR-TABIX fibre with a length of 50 mm and a diameter of 1.3 mm wasemployed. In order to get the material properties of the concrete, different material tests wereaccomplished before starting the slab tests. The compressive strength, the modulus ofelasticity, the flexural strength and - outcoming from this - the equivalent tensile strength weredetermined (see Table 3). The evaluation of the SFRC-properties was carried out according toSFRC-bulletin [DBV 2001]. In a further step, the concrete mixture should be optimised. Themain focus of these optimisations was to reduce the fibre volume, while keeping up the goodconcrete properties of the 100 kg/m mixture. For an additional test specimen of series #1, anew high strength fibre of ARCELOR (type: HE+) was used. The straight fibre with hooked endshas a length of 60 mm and a diameter of 1 mm. Its tensile strength averages 1450 MPa. Thefibre content was reduced to 60 kg per cubic meter (or 0.76 Vol. %). Although the fibre ratiowas scaled down, the behaviour of this optimised mixture shows a better load carrying capacity,especially in the range of higher displacements (see Figure 5).

    0

    1

    2

    3

    4

    5

    6

    7

    0 0,5 1 1,5 2 2,5 3 3

    displacement [mm]

    stress[MPa]

    ,5

    mean values 100 kg/m TABIX mean values 60 kg/m HE+

    Fig. 5 mean values of the SFRC material tests series #1 and #2

    fibre fcm,cyl Ecm feq,ctm,I feq,ctm,II feq,ctm,II,25 age

    content [N/mm] [N/mm] [N/mm] [N/mm] [N/mm] [d]

    S1_SHR_51_V1 61,72 34790 2,49 1,63 1,30 42S1_SHR_51_V2 63,71 33950 2,34 1,43 1,13 66

    S1_HODY_V1 61,72 34790 2,49 1,63 1,30 42S1_HODY_V2 57,56 36190 2,46 1,61 1,27 64

    S1_SHR_51_V3 59,60 38619 2,22 1,81 1,44 45

    S2_SHR_51_V1 46,97 35197 2,41 2,01 1,59 34S2_SHR_51_V2 41,01 30702 1,69 1,27 1,03 36

    S2_HODY_V1 41,49 31207 2,44 2,01 1,59 32S2_HODY_V2 43,99 29678 2,15 1,70 1,35 35

    specimen

    100 kg/m

    TABIX 1.3/50

    60 kg/m

    HE+1.0/60

    Table 3 SFRC material properties series #1 and #2

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    with:

    fcm,cyl: mean value of cylindrical compressive strength

    Ecm: mean value of modulus of elasticity

    feq,ctm,I: mean value of equivalent tensile strength, deformation range I

    feq,ctm,II: mean value of equivalent tensile strength, deformation range II

    feq,ctm,II,25: mean value of equivalent tensile strength, deformation range II, evaluation at 25

    TEST RESULTS

    The first series was carried out in order to determine the possible rotation of steel fibrereinforced composite slabs in the regions of negative bending. In the tests a sufficient rotationcapacity was accomplished. The hogging moment could be kept approximately constant over alarge range of rotation (see Figure 6), which is a prerequisite for a moment-redistribution. Thelast specimen of series #1 (S1_SHR51_V3) having been provided with the optimised concretemixture shows as good results as the other ones although the fibre ratio was reduced to 60 kgper cubic meter. No end-slip was measured during the tests of series #1 run; full shear

    connection between steel sheeting and concrete could be realised.

    -5

    0

    5

    10

    15

    20

    25

    30

    0 5 10 15 20 25 30 35 40

    rotation [mrad]

    momentincl.selfweigth[kNm/m]

    S1_SHR_51_V1 S1_SHR_51_V2 S1_HODY_V1 S1_HODY_V2 S1_SHR_51_V3

    Fig. 6 Moment-rotation diagram of series #1

    Following the good results with the optimised concrete mixture one has decided to use thismixture for the test on continuous slabs (series #2), too.

    In series #2, the good rotation behaviour of series #1 could be confirmed. Figure 7 displays theload bearing behaviour of the steel fibre reinforced continuous slab system exemplarily for thetest S2_SHR51_V2. The load could be increased until the tensile strength of the concrete isreached (range c). After cracking, a plastic hinge (Mpl

    -) with good rotation ability is formed atthe middle support (range d). The hogging moment could be kept approximately constant up tothe failure of the slab, whereas the sagging moments are increased while raising the load. Thehogging moments are redistributed to the span till the sagging plastic moment resistance (Mpl

    +)is reached (range e). Then the system bearing capacity is exhausted. The value of the plasticmoment resistance in the span depends on the composite behaviour of the sheeting. The higheris the dowelling ratio of the sheet the higher is the plastic moment resistance, too. Contrary toseries #1, all continuous slabs of series #2 show end-slip failure. Concerning to its betterdowelling ratio, the re-entrant HOLORIB profile has a better load bearing behaviour as thetrapezoidal HODY sheet. The hogging and sagging moments of series #2 tests are displayed inFigure 8.

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    -100

    -80

    -60

    -40

    -20

    0

    20

    40

    60

    80

    100

    0 5 10 15 20 25 30 35 40

    Loadstep

    hogging/saggingmoments[kNm]

    hogging moment elastic analysis sagging moment elastic analysis hogging moment test sagging moment test

    redistribution

    redistribution

    Mpl-

    Mpl-Mpl

    +Mpl

    +

    c

    d

    e

    Fig. 7 load bearing behaviour exemplarily for test S2_SHR_51_V2

    hogg ing and sagging moments S2_SHR51 series

    -50

    -30

    -10

    10

    30

    50

    70

    90

    5 15 25 35 45 55

    distributed load [kN/m]

    hogging/saggingmoment

    [kNm/m]

    S2_SHR_51_V1 span S2_SHR_51_V2 span

    S2_SHR_51_V1 support S2_SHR_51_V2 support

    hogg ing and sagging mom ents S2_HODY series

    -40

    -30

    -20

    -10

    0

    10

    20

    30

    40

    50

    5 10 15 20 25

    distributed load [kN/m]

    hogging/saggingmoment

    [kNm/m]

    30

    S2_HODY_V1 span S2_HODY_V2 span

    S2_HODY_V1 support S2_HODY_V2 support

    Fig. 8 hogging and sagging moments series #2

    0

    0,5

    1

    1,5

    2

    2,5

    3

    3,5

    4

    4,5

    5

    0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52

    distribu ted load [kN/m]

    crackwidth[mm]

    crack 1 crack 2 crack 3 crack 4

    Fig. 9 crack widths exemplarily for test S2_SHR_51_V2

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    The whole test series #2 as well as the respective sheeting among each other show a goodcorrelation. Figure 9 shows the crack widths subject to the distributed load. In the serviceabilitylimit state range no cracks could be discovered yet. The crack widths do not rise suddenlyduring the load increase. Figure 10 displays the test setup of series #2.

    Fig. 10 Test setup series #2 specimen

    CONCLUSIONS

    Two different test series on composite slabs consisting of steel fibre reinforced concrete toppingand steel sheeting were carried out.

    In both test series, the efficiency of the steel fibre reinforced slab system becomes alreadyapparent. The test results demonstrate that due to the favourable crack-distribution ability ofthe steel fibre reinforced concrete the slabs achieve a good rotation capacity in the hoggingarea. After cracking, the moment could be kept approximately constant over a large range of

    rotation. The tests on continuous composite slabs indicate that large moment redistributions arepossible. After the first plastic hinge arises at the middle support, the load could be increasedfurther on until the system bearing resistance is reached as soon as the second plastic hingeemerges in the span. Pertaining to the ability of moment redistribution, steel fibre reinforcedcontinuous composite slabs constitute an efficient and economical slab system.

    A further test series on steel fibre reinforced composite slabs with various slab depths is inprogress at this time. Here the influence on the load bearing behaviour of slabs with variousthicknesses should be determined. Furthermore, a test series on continuous slabs using steelsheeting with a lower depth (only 16 millimetres) is provided.

    In order to determine the fibre distribution and orientation researches using the computertomography for analysing fibre structures are in progress, too. The results of these researches

    are considered in order to draw conclusions concerning the fibre distribution in the area ofnegative bending. Further information can be gathered from [Schnell and Ackermann 2008].

    Simultaneously, finite element studies are in progress. The model is calibrated according to thematerial tests on beams and to the tests that have already been carried out. After this, finiteelement parametric studies are planned.

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    ACKNOWLEDGEMENTS

    This research was supported by BBR (Bundesamt fr Bauwesen und Raumordnung), ArcelorMittal, Dyckerhoff AG, Holorib GmbH, SAFA GmbH, Spillner Spezialbaustoffe GmbH andWoermann Degussa.

    REFERENCES

    [Ackermann and Schnell 2007] Ackermann, F. P.; Schnell, J .: Innovative steel fibre reinforcedcomposite slabs. fib-Congress: Innovative Materials and Technologies for ConcreteStructures. Proceedings of the 3rd Central European Congress on Concrete Engineering,September 2007, Visegrd, Hungary, pp. 251-256

    [Bode 1998] Euro-Verbundbau, Konstruktion und Berechnung. 2. Auflage. Werner-Verlag,1998.

    [DAfStb 2005] Deutscher Ausschuss fr Stahlbeton (DAfStb): Richtlinie Stahlfaserbeton, 23.Entwurf. Ergnzung zu DIN 1045, Teile 1 bis 4, Dezember 2005.

    [DBV 2001] Deutscher Beton- und Bautechnikverein e.V. (DBV): Merkblatt Stahlfaserbeton,Oktober 2001.

    [DIN 1045-1 2001] DIN 1045-1: Tragwerke aus Beton, Stahlbeton und Spannbeton. Teil 1:Bemessung und Konstruktion. J uli 2001 inkl. 2. Berichtigung J uni 2005.

    [DIN 18800-5 2007] DIN 18800 Part 5: Verbundtragwerke aus Stahl und Beton, Bemessungund Konstruktion. March 2007

    [Droese and Riese 1996] Droese, S; Riese, A.: Belastungsversuche an zwei Durchlauf-Plattenstreifen aus Elementplatten mit Aufbeton aus Stahlfaserbeton. Heft 123, IBMBBraunschweig, 1996.

    [Falkner and Teutsch 2006] Falkner, H.; Teutsch, M.: Stahlfaserbeton Anwendungen undRichtlinie, Betonkalender 2006, Ernst & Sohn, 2006.

    [Gossla and Pepin 2004] Gossla, U.; Pepin, R.: Decken aus selbstverdichtendemStahlfaserbeton. Braunschweiger Bauseminar, 2004.

    [Riese 2006] Riese, A.: Decken aus Elementplatten mit Stahlfaserbetonergnzung.Dissertation, TU Braunschweig, 2006.

    [Sauerborn 1995] Sauerborn, I.: Zur Grenztragfhigkeit von durchlaufenden Verbunddecken.Dissertation TU Kaiserslautern, 1995.

    [Schnell and Ackermann 2008] Schnell, J .; Ackermann, F. P.; Rsch, R.; Sych, T.: Statisticalanalysis of fibre distribution in ultra high performance concrete using computertomography. 2nd International Symposium on Ultra High Performance Concrete, March2008, Kassel, Germany. pp. 145-152.

    [Stark and Brekelmans 1996] Stark, J .W.B.; Brekelmans, J .W.P.M.: Plastic design ofcontinuous composite slabs, Structural Engineering International, Vol. 6, No. 1, February1996, pp. 47-53.