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    Headed stud shear connector for thin ultrahigh-performance concrete

    bridge deck

    Jee-Sang Kim a, Jongwon Kwark b, Changbin Joh b, Sung-Won Yoo c, Kyoung-Chan Lee d,a Seokyeong University, 16-1 Jungneung-Dong, Sungbuk-gu, Seoul 136-704, Koreab Korea Institute of Civil Engineering and Building Technology, 283 Goyangdae-ro, Ilsangseo-gu, Goyang-si, Gyeonggi-do 411-712, Koreac Woosuk University 66 Daehak-ro, Jincheon-eup, Chungcheongbuk-do 365-803, Koread Korea Railroad Research Institute, 176 Cheoldobangmulgwan-ro, Uiwang-si, Gyeonggi-do 437-757, Korea

    a b s t r a c ta r t i c l e i n f o

    Article history:

    Received 4 November 2014

    Accepted 4 February 2015

    Available online xxxx

    Keywords:

    Headed stud

    Shear connector

    Ultrahigh-performance concrete

    Composite beam

    Bridge slab deck

    Ultrahigh-performance concrete (UHPC) provides much higher compressive and tensile strength than

    conventional concrete. UHPC is advantageous for use as a bridge slabdeck owing to its higher strength, stiffness,

    and durability. One drawback, however, is the fact thatthe joint region connectingthe deck and girder generally

    has a thicker cross-section to ensure proper shear connection, which hinders making the overall UHPC deck

    thinner and lighter. In addition, the shear strength of stud shear connectors embedded in UHPC slab has not

    been veried to be the same as that in a conventional concrete deck. This study investigates a stud shear

    connector embedded in a UHPC deck through 15 push-out tests. The ultimate strength of the stud and relative

    slips are measured. The test parameters were chosen to prove the feasibility of a thinner slab. The stud aspect

    ratio, overall height-to-diameter, and cover thickness on top of the stud head requirement are also examined

    to verify the existing geometrical constraints specied in the AASHTO LRFD and Eurocode-4 design codes for

    UHPC decks. It was shown that the aspect ratio can be reduced from 4 to 3.1 without loss of shear strength of

    the stud, and the cover could be reduced from 50 mm to 25 mm without causing a splitting crack at the UHPC

    slab. However, the required ductility demand, 6 mm, was not realized in all cases. Therefore, the stud shear

    connectors in a UHPC deck should be designed according to the elastic criterion.

    2015 Elsevier Ltd. All rights reserved.

    1. Introduction

    Ultrahigh-performance concrete (UHPC) is an advanced composite

    material consisting of a high-strength matrix andbers. It offers signif-

    icantly superior compressive (N150MPa) andtensile strength (N5 MPa)

    compared to conventional concrete, as well as higher modulus of

    elasticity (N40 GPa)[1]. It is typically made from a mixture of Portland

    cement, silica fume, ller, ne aggregate, high-range water reducer,

    water, and steelbers.

    UHPC is being increasingly used worldwide in various components

    of civil infrastructure. In particular, many studies have investigated its

    application to bridgecomponents such as girders, decks,and connection

    joints owing to its higher strength, stiffness, and durability. Many

    studies have investigated the use of UHPC as a deck slab component.

    Saleem et al.[2,3]developed a low-prole UHPC deck system as an

    alternative to an open-grid steel deck. Coreslab Structures Inc. devel-

    oped a wafe-shaped UHPC panel that wasinstalled in a bridge in Little

    Cedar Creek, Wapello County, Iowa, US[4], and Aaleti and Sritharan

    [57] investigated the structural behavior and proposed a design

    guide for this panel system, including connections.

    Efforts have also been made to develop a hybrid beam that

    comprises an FRP girder strengthened with a layer of UHPC slab on

    top. Chen and El-Hacha[810]used 9.5-mm-diameter GFRP studs to

    join the hollow-box FRP girder and a 53-mm-thick UHPC layer on top.

    Nguyen et al.[11,12]developed a hybrid composite beam comprising

    an FRP I-girder topped with a precast UHPC slab, which uses M16

    bolts as shear connectors with an epoxy bonding. The UHPC slab was

    50 mmthick,and thebolt wasembedded to a depthof 35mm, resulting

    in only 15 mm of cover on top of the bolt head and stud height-to-

    diameter aspect ratio of 2.2. This cover thickness and aspect ratio do

    not satisfy the values of 50 mm and 4, respectively,specied in existing

    design codes.

    A UHPC bridge deck can feasibly have a thinner cross-section than a

    conventional concrete deck, as shown in previous studies[512]. How-

    ever, the joint region connecting the deck and the steel girder should

    have thickness comparable to that in the conventional case to ensure

    that shear connectors can be properly installed and embedded in the

    deck in order to conform to existing designcodes. Forexample, two pre-

    viously developed UHPC deck systems have joint connections with

    thicknesses of 127 mm (5 in.)[2,3]and 203 mm (8 in.) [4,5], which

    are no less than that of a conventional concrete deck. Because the

    Journal of Constructional Steel Research 108 (2015) 2330

    Corresponding author. Tel.: +82 31 460 5391; fax: + 82 31 460 5364.

    E-mail addresses:[email protected](J.-S. Kim),[email protected](J. Kwark),

    [email protected](C. Joh),[email protected](S.-W. Yoo),[email protected](K.-C. Lee).

    http://dx.doi.org/10.1016/j.jcsr.2015.02.001

    0143-974X/ 2015 Elsevier Ltd. All rights reserved.

    Contents lists available atScienceDirect

    Journal of Constructional Steel Research

    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_Precast_Concrete_Slabs_for_Accelerated_Bridge_Construction?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/251542995_Behaviour_of_hybrid_FRP-UHPC_beams_in_flexure_under_fatigue_loading?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/251542995_Behaviour_of_hybrid_FRP-UHPC_beams_in_flexure_under_fatigue_loading?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/256968708_Damage_tolerance_and_residual_strength_of_hybrid_FRP-UHPC_beam?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/256968708_Damage_tolerance_and_residual_strength_of_hybrid_FRP-UHPC_beam?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/262673201_Flexural_Behavior_of_Hybrid_Composite_Beams?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/262673201_Flexural_Behavior_of_Hybrid_Composite_Beams?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/251669986_Behaviour_of_hybrid_FRP-UHPC_beams_subjected_to_static_flexural_loading?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/251669986_Behaviour_of_hybrid_FRP-UHPC_beams_subjected_to_static_flexural_loading?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/265277498_Ultra-High-Performance_Concrete_Bridge_Deck_Reinforced_with_High-Strength_Steel?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/265277498_Ultra-High-Performance_Concrete_Bridge_Deck_Reinforced_with_High-Strength_Steel?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==http://www.sciencedirect.com/science/journal/0143974Xhttp://dx.doi.org/10.1016/j.jcsr.2015.02.001mailto:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]://dx.doi.org/10.1016/j.jcsr.2015.02.001http://crossmark.crossref.org/dialog/?doi=10.1016/j.jcsr.2015.02.001&domain=pdf

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    thinnest sections of the UHPC deck are 32 mm (1.25 in.) [2,3]and

    63.5 mm (2.5 in.) [47], a shear connection requires a signicantly

    thick UHPC deck; this goes against the design objective of reducing

    the self-weight and lowering the prole of the deck. This study investi-

    gates the structural behavior of stud shear connectors embedded in

    UHPC decks of various thicknesses and conrms the validity of existing

    design codes for this application.

    Since 1960, composite structures have been widely used owing to

    their structural ef

    ciency. They typically consist of a steel girder andconcrete deck that transfers shear force through suitable shear connec-

    tors such as angles, channel sections, headed studs, and perforated ribs.

    Headed studs are used most commonly owing to their simple and quick

    installation using a stud-welding gun and superior ductility than other

    types of shear connectors.

    The static strength of studshear connectors was originally evaluated

    based on Ollgaard et al.s[13]early experimental work. They showed

    that the static strength of a stud shear connector is controlled by two

    different failure mechanisms: surroundingconcrete crushing failure, re-

    lated to concretes compressive strength,fc0

    , and shearing failure of the

    shank of the stud, related to the studs ultimate tensile strength,Fu. The

    smaller value between the two different mechanisms controls the

    designshearstrengths of a stud shear connector. TheAASHTO LRFD pro-

    vision 6.10.10.4.3[14]de

    nes the design static strength of a stud shearconnector,Qr, as

    Qr scQn sc0:5Asc

    ffiffiffiffiffiffiffiffiffiffif

    0

    cEc

    q sc FuAsc 1

    where the resistancefactor,sc, is taken as 0.85. Eurocode-4 [15] denes

    the design static shear strength, PRd, as

    PRd 0:29d

    2ffiffiffiffiffiffiffiffiffiffif

    0

    cEc

    q

    v

    0:8 FuAscv

    2

    where thepartial factor,v, is taken as 1.25, and an aspect ratio factor,,

    which depends upon the stud height-to-diameter ratio, hsc/d, istakenas

    0.2(hsc/d+ 1) for 3 hsc/d 4 and 1 forhsc/d 4.

    Differentdesigncodes have differentresistance or partial factors. How-ever, they are similar in that the left-hand side terms of Eqs. (1) and (2)

    refer to concrete crushing failure in terms of the surrounding concrete

    strength (fc' ) and modulus of elasticity (Ec) but not themechanical prop-

    erty of the embedded stud. Furthermore, the right-hand side terms of

    Eqs. (1) and (2) refer to stud shank failure in terms of the ultimate ten-

    sile strength (Fu) of the stud but not the mechanical propertyof the sur-

    rounding concrete. The concrete crushing failure controls when the

    compressive strength of the concrete is low or moderate, and the stud

    shank failure does when the strength is high. The threshold between

    the two failure modes usually lies at a concrete compressive strength

    of 3040 MPa.

    Considering that the compressive strength of UHPC exceeds

    150 MPa, the stud shank failure mode obviously always controls the

    static strength of the stud shear connector. Ollgaard et al.[13]reported

    that the concrete strength of their specimens was 1835 MPa. There-

    fore, the validity of existing design codes for stud shear connectors

    should be conrmed for UHPC applications because it provides much

    higher concrete strength than before.

    Geometrical constraints are another important issue with regard to

    UHPC decks in that they must be as thin as possible to reduce their

    weight and construction costs. The constraints of existing design codes

    may result in a UHPC deck with a thicker cross-section at the joint re-

    gion between the deck and the girder. The thickness of wafe deck

    panels [47] is 63.5 mm at the thinnest region between ribs but

    200 mm at the joint region. Saleem[2,3]developed a low-prole deck

    system that is as thin as 31 mm between ribs but is 125-mm-thick at

    the joints. This study investigates a joint region with a thickness of

    only 75 mm to overcome the stocky joint region resulting when apply-

    ing a current design code to the shear connectors embedded in a UHPC

    deck.

    Therst geometrical constraint is the aspect ratio between the over-

    all stud height and the shank diameter. The AASHTO LRFD[14]and

    Eurocode-4[15]design codes require an aspect ratio of at least fourand three, respectively. The second constraint is the concrete cover

    thickness over the stud head to prevent a longitudinal splitting crack

    on top of the shear connector. The AASHTO LRFD provision 6.10.10.1.4

    [14]regulates that the clear depth of the concrete cover over the top

    of a shear connector should not be less than 50 mm and should pene-

    trate at least 50 mm into the concrete deck. For example, when using

    the most common diameter of 17 mm for a stud for a bridge deck and

    Table 1

    Push-out test specimens.

    Specimen

    group

    Deck

    thickness

    (mm)

    Stud shear connector Cover

    thickness

    (mm)

    EA

    Height

    (mm)

    Diameter

    (mm)

    Aspect ratio

    (height/diameter)

    Normal 150 100 22 4.5 50 3

    UHPC-I 150 100 22 4.5 50 3

    UHPC-II 100 65 16 4.1 35 3

    UHPC-III 100 50 16 3.1 50 3

    UHPC-IV 75 50 16 3.1 25 3

    Fig. 1.Push-out specimen dimensions.

    24 J.-S. Kim et al. / Journal of Constructional Steel Research 108 (2015) 2330

    https://www.researchgate.net/publication/254593292_Alternatives_to_Steel_Grid_Bridge_Decks?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/265277498_Ultra-High-Performance_Concrete_Bridge_Deck_Reinforced_with_High-Strength_Steel?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/264824216_Design_of_Ultrahigh-Performance_Concrete_Waffle_Deck_for_Accelerated_Bridge_Construction?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/264824216_Design_of_Ultrahigh-Performance_Concrete_Waffle_Deck_for_Accelerated_Bridge_Construction?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/254593292_Alternatives_to_Steel_Grid_Bridge_Decks?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/265277498_Ultra-High-Performance_Concrete_Bridge_Deck_Reinforced_with_High-Strength_Steel?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/254593292_Alternatives_to_Steel_Grid_Bridge_Decks?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/254593292_Alternatives_to_Steel_Grid_Bridge_Decks?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/264824216_Design_of_Ultrahigh-Performance_Concrete_Waffle_Deck_for_Accelerated_Bridge_Construction?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/264824216_Design_of_Ultrahigh-Performance_Concrete_Waffle_Deck_for_Accelerated_Bridge_Construction?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/265277498_Ultra-High-Performance_Concrete_Bridge_Deck_Reinforced_with_High-Strength_Steel?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/265277498_Ultra-High-Performance_Concrete_Bridge_Deck_Reinforced_with_High-Strength_Steel?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==

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    when following the AASHTO LRFD design code[13], the deck thickness

    should be at least four times the diameter plus 50 mm cover, for a thick-

    ness of at least 118 mm. This is one reason why the composite joint is

    chunky.

    The Eurocode-4 provision 6.6.5.1[15]regulates that the surface of a

    connector should not extend less than 30 mm clear above the bottom

    reinforcement, and provision 6.6.5.2 regulates that the cover should

    not be less than that required for reinforcement adjacent to the same

    surface of concrete. As the UHPC deck does not always enclose rein-

    forcement, applying the cover thickness given in the Eurocode-4 design

    code[15]is not possible.

    The UHPC material provides much higher strength and durability

    [1], and therefore, the deck thickness can be much less than when

    using conventional concrete. However, this may not be the case at the

    deck girderjoint owing to thegeometrical constraints forthe embedded

    shear connectors to ensure the transfer of the longitudinal shear force.

    This study investigates the static strength and behavioral validity of

    stud shear connectors for a thin UHPC solid slab deck.

    Several factors limit the use of stud shear connectors in a thin UHPC

    deck slab. The rst is concern over whether the stud shear connector

    embedded in UHPC provides equivalent static strength compared to

    that in conventional concrete. The second is concern related to the geo-

    metrical properties; the installation of stud shear connectors is subject

    to geometrical constraints such as the height-to-diameter ratio and

    cover thickness over the stud head, and existing design codes may

    not, in fact, allow the use of stud shear connectors for thin deck slabs.

    The last is concern over the ductility provided by stud shear connec-

    torsbecause the strengthof the surrounding concrete is muchhigherthan that of conventional concrete such that the structural behavior

    may differ from stud shear connectors embedded in conventional

    concrete.

    2. Experimental program

    Shear connectors at a exural composite member resist the relative

    slip occurringat theinterface between the girder and the slab deck. The

    best way to measure the static strength of the shearconnectors is a ex-

    ural beam test under a distributed load. However, to reducethe cost and

    time, a direct push-out test is generally used instead. The experiment in

    this study follows a standard test procedure given in the Eurocode-4-1-

    1 design code[16].Five groups of specimensNormal and UHPC-I to UHPC-IVare pre-

    pared, as listed inTable 1, and three specimensA, B, and Care pre-

    pared for each group. The key variables of the test program are the

    deck thickness and resulting stud aspect ratio and cover. The Normal

    case has specimens with a conventional reinforced concrete slab for cal-

    ibrating the test setup and for the purpose of comparison. The UHPC-I

    case has identical dimensions to the Normal case and differs only in

    that the deck is made of UHPC instead of conventional concrete. Both

    the Normal and the UHPC-I specimens have the same thickness as the

    conventional concrete deck, and the stud shear connector satises the

    given geometrical constraints: aspect ratio of at least four and cover of

    at least 50 mm. UHPC-II and UHPC-III specimens have 100-mm-thick

    decks. The cover on top of the stud in UHPC-II specimens is 35 mm

    thick, which is less than the requirement. UHPC-III specimens satisfy

    the cover requirement; however, the aspect ratio is only 3.1, which is

    less than the required value of four. UHPC-IV specimens have the thin-

    nest slab, which is only 75 mm thick, and its cover thickness and aspect

    ratio of 25 mm and 3.1, respectively, do not satisfy the requirements.

    The specimens are prepared for a two-face push-out test. Four studs

    are welded at eachface, as shown in Fig. 1. These headed studs meet the

    Type B requirements specied in AWS.D 1.1[17], namely, minimum

    yield strength of 350 MPa and minimum tensile strength of 450 MPa,

    and they are welded on the ange using a conventional stud-welding

    gun. In this study, studs with two different diameters are used:

    22 mm for Normal and UHPC-I groups and 16 mm for the other groups,

    as shown inTable 1. The stud diameters are chosen according to the

    thickness of the deck to meet the requirement of aspect ratio of four;

    Normal and UHPC-I groups have 150-mm-thick slabs and the other

    groups have thinner slabs. The tensile and shear strength properties ofheadedstuds were testedfrom a direct tension anddouble-shearguillo-

    tine tests. The direct tension test xture used for this purpose was sim-

    ilar to that suggested in AWS D1.1-2000[17]. A double-shear guillotine

    Table 2

    UHPC mixture.

    w/b ratio Cement Silica

    fume

    Filler Fine

    aggregate

    Water

    reducer

    Steel

    ber

    0.07 1.0 0.25 0.3 1.1 0.016 16.5 mm 1%

    19.5 mm 1%

    Fig. 2.UHPC casting in horizontal position.

    120mm

    FL

    FR

    BR

    BL

    100mm

    Back

    Front Transverse

    Displacement

    Fig. 3.Displacement measurement plan.

    25J.-S. Kim et al. / Journal of Constructional Steel Research 108 (2015) 2330

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    test was conducted on the middle third of the stud shank to determine

    the steel shear strength; this test was conducted using an apparatus

    similar to that used by Anderson and Meinheit[18].

    Table 2provides details of the mixture of the UHPC. Steel bers of

    two different lengths, 16.5 and 19.5 mm, are mixed together with 1%

    volume each. The UHPC is designed for a characteristic compressive

    strength of 180 MPa, the measured minimum strength was 200 MPa;

    measured minimum tensile strength was 18 MPa, and the measured

    modulus of elasticity was 4.5 105 MPa. The measured compressive

    strength of the Normal specimen group was 35 MPa.

    Steel sections used for simulating a steel girder have width, depth,

    web thickness,andange thickness of 300, 300, 10, and 15 mm, respec-

    tively. UHPC cannot easily be cast in the vertical direction, and the cast-ing direction may affect the test result. Therefore, the steel section is cut

    at themiddle ofthe web inthe longitudinaldirection and the caston top

    of a ange to simulate theeld application casting direction, as shown

    in Fig.2. Thespecimens were steam-cured andthe initialcuring temper-

    ature was 40 C, and it was increased by 10 C every hour up to 90 C.

    Steam-curing was done for three days and the temperature was gradu-

    ally decreased at the end of the curing process. After curing, the push-

    out specimens were prepared with two separate faces bolted together

    at the cut section of the web using an M24 high-tension bolt.

    The prepared specimens were loaded using a 2000 kN universal test

    machine. Assuming stud shank failure from Eq. (1), thefailure load was

    expected to be 1368 kN considering eight studs for each specimen. Ac-

    cording to the Eurocode-4-1-1 design code[16], cyclic loads were ap-

    plied to stabilize the specimen and break the bond between the steelsection and thedeck. The cyclic load was5%40% of the expected failure

    loadwith loading speed of 0.82 kN/s. After cyclicloading, the specimens

    were loaded constantly by increasing the displacement control at a

    speed of 0.005 mm/s until failure.

    The relative slips between the steel section and the slab deck are

    measured using four LVDTs located 120 mm apart from the top ofeach slab, as shown inFig. 3. To ensure avoiding the separation of the

    slab from the steel section, lateral supporting bars are installed at the

    top and bottom of the specimen, and any possible separation is moni-

    tored using two LVDTs located outward of each slabs, as shown in Fig. 4.

    3. Test results and discussions

    3.1. Stud tensile and double shear test on bare stud specimens

    Table 3summarizes the measured tension and shear test results, in

    which theresulting values for the shear test were divided by two to ob-

    tain resisting force for one shear surface. The tensile yield and ultimate

    strength of each of these steels exceeds the AWS D1.1-2000 [17]

    requirements of 350 and 450 MPa, respectively. Fig. 5 shows the

    strainstress curve obtained from the tension test. Yielding behavior

    was clearly observed for the tensile test. On the other hand, the guillo-

    tine test results do not show a clear yield or proportional limit, as

    shown inFig. 6. The typical failure of a stud loaded in double shear is

    shown inFig. 7.

    The ratio of the measured shear strength to the measured tensile

    strength is 0.80 and 0.82, and the ratio to the nominal tensile strength

    (450 MPa) is 0.87 and 0.85, for the16 mm and 22 mmstuds, respective-

    ly. This value is larger than that of 0.65 obtained by Anderson and

    Meinheit[18]. The higher ratio appears attributable to the fact that the

    xture holding stud for double shear does not fully restrain the stud

    specimen, which eventually involves additional bending other than di-

    rect shearing load. In reality, a shear studexperiences a combined action

    of shearing and bending. It is difcult to estimate the exact contributionof the two different mechanical behaviors. To evaluate shearing resis-

    tance only, the stud head should be fully restrained in the vertical as

    well as the horizontal directions to eliminate the bending action.

    3.2. Ultimate strength and initial stiffness of stud embedded in UHPC deck

    Themost important dataobtained from the push-out test arethe ap-

    plied ultimate load at failure. The resulting ultimate failure load (Pmax)

    and relative slips are analyzed by the procedure given in the

    Eurocode-4-1-1 design code [16], which denes the characteristic resis-

    tance (PRk) as the minimum failure load is reduced by 10%. The slip ca-

    pacity of a specimen (u) is taken as themaximum slip measured at the

    characteristic load level. The characteristic slip capacity (uk) is takenas

    Fig. 4.Push-out test setup and lateral supporting bars.

    Table 3

    Stud tension and Guillotine test result.

    Stud

    diameter

    [mm]

    Tension test Guillotine test

    (per interface)

    Yield

    force

    [kN]

    Yield

    stress

    [MPa]

    Ultimate

    force [kN]

    Ultimate

    stress [MPa]

    Ultimate

    force [kN]

    Ultimate

    stress

    [MPa]

    16 77 384 97 484 78 390

    22 141 372 177 466 145 380

    0

    100

    200

    300

    400

    500

    0 0.02 0.04 0.06 0.08 0.1

    S

    tress[MPa]

    Strain

    16 mm

    22mm

    Fig. 5.Direct tension test result on bare stud specimens.

    26 J.-S. Kim et al. / Journal of Constructional Steel Research 108 (2015) 2330

    https://www.researchgate.net/publication/274274961_Design_Criteria_for_Headed_Stud_Groups_in_Shear_Part_1_-_Steel_Capacity_and_Back_Edge_Effects?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/274274961_Design_Criteria_for_Headed_Stud_Groups_in_Shear_Part_1_-_Steel_Capacity_and_Back_Edge_Effects?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/274274961_Design_Criteria_for_Headed_Stud_Groups_in_Shear_Part_1_-_Steel_Capacity_and_Back_Edge_Effects?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/274274961_Design_Criteria_for_Headed_Stud_Groups_in_Shear_Part_1_-_Steel_Capacity_and_Back_Edge_Effects?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==

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    the minimum test value ofu was reduced by 10%. Table 4 shows

    detailed test results for each specimen.

    Because the concrete failure mode never controls the shear connec-

    torembeddedin UHPC, theultimate strength of studshearconnectors is

    obtained asAscFuaccording to the AASHTO LRFD design code[14] if the

    effect of the resistance factor is excluded.Fig. 8shows the curve of nor-

    malized applied forces toAscFuand relative slip. Considering the ulti-

    mate tensile strength, Fu, of the stud material (450 MPa) and the

    shank diameter of the stud (22 mm) for UHPC-I, the tensile strength

    of a UHPC-I specimen is expected to be at least 171 kN. For UHPC-II, -

    III, and -IV specimens, the minimum tensile strength is expected to be

    90 kN considering a stud diameter of 16 mm. The Eurocode-4 design

    codes[15],given by Eq.(2), evaluate the ultimate strength to be 20%

    smaller than that evaluated by the AASHTO LRFD design code [13]. In

    Eq. (2), when excluding the effect of the partial factor, the expected ten-

    sile strengths are 137 kN for Normal and UHPC-I and 72 kN for others.

    The ratios between the measured stud characteristic shear strength

    (PRk) from the push-out tests and measured ultimate tensile strength

    (Pu_test) from the direct tension test and those expected from the

    AASHTO LRFD[14] and Eurocode-4 [15]design codes are listed in

    Table 5. The shear strength of the stud in the Normal specimen group

    is almost identical to that from the design code Eq. (2)of Eurocode-4

    [15]. From this observation, it can be said that the test setup used in

    the experimental program is reasonable.

    First, it should be noted that the measured ultimate strength of a

    stud shear connector does not show signicant difference in all cases

    but the Normal one. This suggests that the slabthickness does not affect

    the strength of the stud shear connector. In particular, despite the

    Eurocode-4 design code[15], Eq.(2)species reduced static strength

    of the stud for a small aspect ratio; however, this is not the case for a

    UHPC slab deck. The UHPC-II and -IV cases, which do not satisfy the

    cover thickness requirement specied in the AASHTO LRFD designcode[14], did not show any splitting crack.

    The measured static strengths of the stud shear connector embed-

    ded in the UHPC are 2%13% higher than the nominal tensile strength

    of the stud itself, and they correspond to the AASHTOLRFD designequa-

    tion [14]. They are evaluated 27%42% more conservatively if the

    Eurocode-4 design equation [15] is applied. Therefore, the shear

    strength of stud shear connector in UHPC is adequate to be evaluated

    in accordance with the AASHTO LRFD[14]rather than the Eurocode-4

    [15]design code.

    The initial stiffness of stud shear connectors is assumed innite ac-

    cording to the strength design concept. In reality, they show some initial

    slip in the early loading stage owing to surrounding concrete cracking

    and stud deforming. The initial stiffness is calculated from the relative

    slip between 10% and 40% of the ultimate load, as shown in Table 6.

    The average stiffness of Normal specimens is 336 kN/mm for single

    studs, and UHPC-I specimens show the highest stiffness of 762 kN/mm.

    UHPC-III specimens have a stiffness of 736 kN/mm, which is comparable

    to that of UHPC-I specimens. UHPC-II and UHPC-IV specimens have

    slightly smaller stiffnesses (598 and 538 kN/mm, respectively) than

    UHPC-I and UHPC-III.

    Oehlers and Coughlan[19] proposed an equation for estimating ini-

    tial shear stiffness from 116 push-out tests:

    Ksi Pmax=d 0:160:0017f0

    c

    3

    where the initial stud stiffness (Ksi) is obtained from the shear stud

    strength (Pmax), diameter of stud (d), and concrete compressive

    strength (fc).

    0

    100

    200

    300

    400

    500

    0 2 4 6 8 10 12

    Stress[MPa]

    Displacement [mm]

    16mm

    22mm

    Fig. 6.Guillotine double shear test result for bare stud specimens.

    Fig. 7.Typical failure of stud after guillotine double shear test.

    Table 4

    Push-out test results for single stud.

    Specimens Pmax[kN] PRk[kN] u[mm] uk[mm]

    Normal A 158 130 15.68 9.80

    B 148 13.56

    C 145 10.89

    UHPC-I A 198 174 7.66 5.16

    B 193 5.73

    C 212 7.18

    UHPC-II A 123 103 4.98 3.62

    B 120 4.02

    C 114 4.21

    UHPC-III A 105 92 4.84 4.36

    B 103 5.93

    C 111 5.64

    UHPC-IV A 109 98 5.42 4.54

    B 109 5.04

    C 117 5.18

    27J.-S. Kim et al. / Journal of Constructional Steel Research 108 (2015) 2330

    https://www.researchgate.net/publication/256401392_The_shear_stiffness_of_stud_shear_connectors_in_composite_beams?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/256401392_The_shear_stiffness_of_stud_shear_connectors_in_composite_beams?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==

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    Applying Eq.(3)to the Normal specimen group provides an initialstiffness of 68 kN/mm, which is signicantly less than the test results.

    However, Shim et al.[20]presented initial stiffness results of large di-

    ameter (25 mm and 30 mm) studs from push-out tests, which varied

    from about 200 to 400 kN/mm. It can be said that test results for the

    Normal specimen group match those of Shim et al. [20]. The results in

    this study indicate that a stud embedded in the UHPC provides at least

    60% higher stiffness than that in conventional concrete. Based on the re-

    sults for UHPC-II and UHPC-IV, the cover thicknessmay affect the initial

    stud stiffness: a thicker cover generates higher stud stiffness.

    3.3. Aspect ratio of stud

    The aspect ratio is another important issue to be considered whenapplying stud shear connectors to a thin deck slab. The AASHTO LRFD

    [14] and Eurocode-4[15]design codes require an aspect ratio of at

    least four, although the latter allows an aspect ratio of three only if the

    strength is reduced, as given in Eq. (2). A UHPC slab deck is advanta-

    geous in that the deck slab can be made as thin as possible. Applying a

    stud shear connector to a thin slab naturally reduces the stud height,

    and the stud diameter should also be smaller to satisfy the aspect ratio

    requirement, which requires a greater number of studs and therefore

    increased construction time. Considering that the strength of the sur-

    rounding concrete in the case of a UHPC deck is much stronger than

    that in conventional applications, this study investigates the validity of

    a smaller aspect ratio. Aspect ratios of 4.5, 4.1, 3.1, and 3.1 were tested

    for each specimen groupUHPC-I to -IV.

    The test results do not show any signi

    cant difference with changesin theaspect ratio. Thestud shear connectorshowsobvious shearing be-

    havior and not bending because of the higher stiffness and strength of

    the surrounding concrete. Xu and Sugiura[21]showed that lower con-

    crete strength might lead to relatively more obvious bending

    deformation with shear deformation in the push direction. In Fig. 9,the fractured cross-section of the stud shows a clean-cut immediately

    above the welding area, which means that the shearing behavior is pri-

    marily responsible for stud fracture. Therefore, an aspect ratio as low as

    3.1, as investigated in this test program, is allowable for the stud shear

    connectors embedded in UHPC without a loss of strength.

    3.4. Cover thickness on top of stud head

    AASHTO LRFD[14]requires a minimum cover thickness of at least

    50 mm (2 in.) over the stud head. This makes it difcult to realize a

    thin UHPC slab deck, and it could be an overly conservative solution

    considering the mechanical properties of UHPC. In this test program,

    the cover of UHPC-II and -IV specimens is 35 and 25 mm, respectively.The resulting static strength of UHPC-II and -IV specimens is 12% and

    7% higher than that of UHPC-III specimens. Although these specimens

    show a ductility issue, the same is also observed in UHPC-III specimens,

    whose cover is 50 mm. This ductility issue is therefore considered to be

    independent of the cover thickness. The test results show that speci-

    mens with shallow covers do not suffer any strength reduction, crack-

    ing, and spalling of the cover as seen at the surface of the slab deck.

    There is some reduction in the initial stiffness owing to the shallow

    cover thickness; however, it remains much larger thanthat of a conven-

    tional concrete deck. Therefore, the regulation of the minimum

    0

    0.2

    0.4

    0.6

    0.8

    1

    1.2

    1.4

    0 1 2 3 4 5 6AppliedForce/Nominal

    UltimateForce[P/Asc

    Fu

    ]

    Relative Slip [mm]

    UHPC-I-B

    UHPC-II-C

    UHPC-III-B

    UHPC-IV-B

    Fig. 8.Curve of normalized applied force with respect to relative slip.

    Table 5

    Test results compared to shear strength from the direct tension test and design codes.

    Specimens PRk/Pu_test PRk/AASHTO [AscFu] PRk/Eurocode [0.8AscFu]

    Normal 0.76 0.85 0.99

    UHPC-I 1.02 1.06 1.32

    UHPC-II 1.10 1.18 1.48

    UHPC-III 0.98 1.06 1.32

    UHPC-IV 1.03 1.11 1.39

    Table 6

    Stiffness of a stud shear connector.

    Specimens Stiffness [kN/mm] Average stiffnes s [kN/mm]

    Normal A 309 336

    B 379

    C 322

    UHPC-I A 754 762

    B 714

    C 816

    UHPC-II A 532 598

    B 571

    C 689

    UHPC-III A 1088 736

    B 535

    C 585

    UHPC-IV A 340 538

    B 487

    C 788

    28 J.-S. Kim et al. / Journal of Constructional Steel Research 108 (2015) 2330

    https://www.researchgate.net/publication/223502114_Static_behavior_of_large_stud_shear_connectors?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/223502114_Static_behavior_of_large_stud_shear_connectors?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/271635568_FEM_analysis_on_failure_development_of_group_studs_shear_connector_under_effects_of_concrete_strength_and_stud_dimension?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/223502114_Static_behavior_of_large_stud_shear_connectors?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/223502114_Static_behavior_of_large_stud_shear_connectors?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/271635568_FEM_analysis_on_failure_development_of_group_studs_shear_connector_under_effects_of_concrete_strength_and_stud_dimension?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==

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    thickness of the cover over the stud head can be relaxed to at least

    25 mm for a UHPC slab deck.

    3.5. Ductility of stud

    Twostrategies have been used forthe static designof studshearcon-

    nectors: elastic and strength designs. The elastic design results in a var-

    iable pitch, which is narrower for the high shear zone usually at the end

    of beams and wider for the low shear zone usually at the center of the

    beam. On the other hand, the strength design concept assumes that all

    studs maintain their ultimate strength until failure at the ultimate

    state of the entire structure, which results in a constant pitch regardlessof the longitudinal location of the beam. Nowadays, most design codes

    are based on the strength design concept. However, the ductility de-

    mand should always be guaranteed to ensure the strength design con-

    cept. Although the ductility demand can be variable for each structure,

    the Eurocode-4 design code[16]requires the characteristic relative

    slip (uk) to be at least 6 mm from the push-out test as a criterion for

    the ductility demand.

    The test results of this study showed that most test specimens, ex-

    cept for UHPC-I-A and -C, had unsatisfactory ductility, as listed in

    Table 4. Hegger et al. [22] also reported the same conclusions, in

    which the characteristic relative slip was 5.7 mm for a shear connector

    embedded in high-strength concrete. Therefore, another measure is re-

    quired to enhance the ductility of a stud shear connector embedded in a

    UHPC. Otherwise, exact composite analysis can provide a more preciseductility demand that may be less than 6 mm for a specic structure.

    In such a case, a stud shear connector can be used for a UHPC slab

    deck with a constant pitch.

    In order to overcome the ductility issue, stud shear connectors in

    UHPC can be designed based on the elastic theory instead of the plastic.

    The elastic theory, which results in variable stud pitches, provides nar-

    row spacing near the support for resisting large shear forces and

    wider at the mid-span for smaller shear forces. In contrast, the plastic

    theory, which results in a constant pitch across the entire span, is

    based on the ductile behavior of the stud. The experiment program in

    this study showed that shear studs in UHPC do not meet the ductility

    demand, which does not allow the application of the plastic theory.

    Therefore, unless the ductility problem is resolved, stud shear connec-

    tors in a UHPC should not be designed using the plastic theory with

    constant longitudinal pitch; instead, the elastic theory and the resulting

    variable longitudinal pitches should be applied.

    4. Conclusions

    This study investigates the structural performance and validity of

    stud shear connectors for a thin UHPC slab deck. The following conclu-

    sions can be derived from the test program:

    1) The static strength of stud shear connectors embedded in a UHPC is

    always controlled by steel failure. This indicates that strength is af-

    fected only by the stud diameter and the ultimate strength of the

    stud material and not by the surrounding concrete strength if

    existing design codes are applied.

    2) The test program proves that the actual static strength of shear con-

    nectors embedded in a UHPC is greater than that obtained by the

    AASHTO LRFD design calculation [14] bya margin of2%13%. There-

    fore, the AASHTO LFRD design code [14]can be used to evaluate the

    ultimate strength of a stud shear connector in a UHPC. A comparison

    withthe Eurocode-4 design code [15] provides a marginof 27%42%,

    which may lead to a relatively conservative result.

    3) Theaspect ratio of the stud height-to-diameter is limited to at least 4

    in existing design codes. The test program in this study proves that

    the aspect ratio can be as low as 3.1 because it does not have muchimpact on the structural behavior or performance of stud shear con-

    nectors.

    4) The cover thickness over the stud head is limited to 50 mm in the

    AASHTO LRFD design code[14]. The test program proves that a

    cover thickness even as low as 25 mm does not lead to any cracking

    or spalling in the UHPC slab deck or reduction in the static strength

    of a stud shear connector.

    5) According to the Eurocode-4 design code[16], the stud shear con-

    nectors should provide a characteristic relative slip of at least

    6 mm to guarantee the ductile behavior of the stud. The test result

    shows that the stud shear connectors embedded in a UHPC provide

    characteristic relative slips of 3.85.3 mm that do not satisfy the re-

    quired ductility demand of 6 mm. Therefore, another measure

    should be used to resolve this ductility issue in order to use studshear connectors for a thin UHPC slab. Otherwise, an elastic design

    should be applied for stud shear connectors for a UHPC deck,

    resulting in a variable stud pitch rather than a constant pitch.

    6) A UHPC slab deck for composite construction can be as thin as

    75 mm using stud shear connectors with a diameter of 16 mm and

    height of 50 mm even at the deck girder joint region.

    Acknowledgements

    This research was supported by a grant (13SCIPA02) from the Smart

    Civil Infrastructure Research Program funded by the Ministry of Land,

    Infrastructure and Transport (MOLIT) of the Korean Government and

    Korea Agency for Infrastructure Technology Advancement (KAIA).

    References

    [1] Russell HG, Graybeal BA. Ultra-high Performance Concrete: A State-of-the-Art Re-port for the Bridge Community. Publication No. FHWA-HRT-13-060. Federal High-way Administration; 2013.

    [2] Saleem MA. Alternative to Steel Grid Bridge Decks. PhD Dissertation Florida Interna-tional University; 2011.

    [3] Saleem MA, Mirmiran A, Xia J, Mackie K. Ultra-high-performance concrete bridgedeck reinforced with high-strength steel. ACI Struct J 2011;108(5):6019.

    [4] Heimann J. The implementation of full depth UHPC wafe bridge deck panels. Pub-lication No. FHWA-HIF-13-031. Federal Highway Administration Highways for LIFE;2013.

    [5] Aaleti S, Petersen B, Sritharan S. Design guide for precast UHPC wafe bridge deckpanel system, including connections. Publication No. FHWA-HIF-13-032. FederalHighway Administration Highways for LIFE; 2013.

    [6] Aaleti S, et al. Structural behavior of wafe bridge deck panels and connections ofprecast ultra-high-performance concreteexperimental evaluation, transportation

    research record. J Transp Res Board 2011;2251:82

    92.

    Fig. 9.Fractured section of stud shear connector after failure.

    29J.-S. Kim et al. / Journal of Constructional Steel Research 108 (2015) 2330

    https://www.researchgate.net/publication/233503916_Load-Deformation_Behavior_of_Shear_Connectors_in_High_Strength_Concrete_Subjected_to_Static_and_Fatigue_Loading?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0075http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0075http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0075https://www.researchgate.net/publication/254593292_Alternatives_to_Steel_Grid_Bridge_Decks?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/254593292_Alternatives_to_Steel_Grid_Bridge_Decks?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/265277498_Ultra-High-Performance_Concrete_Bridge_Deck_Reinforced_with_High-Strength_Steel?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/265277498_Ultra-High-Performance_Concrete_Bridge_Deck_Reinforced_with_High-Strength_Steel?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/265277498_Ultra-High-Performance_Concrete_Bridge_Deck_Reinforced_with_High-Strength_Steel?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/265277498_Ultra-High-Performance_Concrete_Bridge_Deck_Reinforced_with_High-Strength_Steel?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0085http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0085http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0085http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0085http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0085http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0090http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0090http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0090http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0090http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0090http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0015http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0015http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0015http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0015http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0015http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0015http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0015http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0015http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0015https://www.researchgate.net/publication/254593292_Alternatives_to_Steel_Grid_Bridge_Decks?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/254593292_Alternatives_to_Steel_Grid_Bridge_Decks?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/233503916_Load-Deformation_Behavior_of_Shear_Connectors_in_High_Strength_Concrete_Subjected_to_Static_and_Fatigue_Loading?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/265277498_Ultra-High-Performance_Concrete_Bridge_Deck_Reinforced_with_High-Strength_Steel?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==https://www.researchgate.net/publication/265277498_Ultra-High-Performance_Concrete_Bridge_Deck_Reinforced_with_High-Strength_Steel?el=1_x_8&enrichId=rgreq-dea6df31162844738557512780347604&enrichSource=Y292ZXJQYWdlOzI3MzM5OTM5NDtBUzozMTYxNjE5NDA0OTIyODlAMTQ1MjM5MDI4ODQzMA==http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0015http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0015http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0015http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0090http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0090http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0090http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0085http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0085http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0085http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0010http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0010http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0080http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0080http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0075http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0075http://refhub.elsevier.com/S0143-974X(15)00034-6/rf0075

  • 7/26/2019 gsgdgdgdagadgd

    8/8

    [7] Aaleti S, Sritharan S. Designof ultrahigh-performance concrete wafe deckfor accel-erated bridge construction. TransportRes Rec:J TranspRes Board 2014;2406:1222.

    [8] Chen D, El-Hacha R. Behaviour of hybrid FRPUHPC beams in exure under fatigueloading. Compos Struct 2011;94:25366.

    [9] El-Hacha R, Chen D. Behaviour of hybridFRP-UHPCbeams subjected to static exur-al loading. Compos Part B 2012;43:58293.

    [10] Chen D, El-Hacha R. Damage tolerance and residual strength of hybrid FRP-UHPCbeam. Eng Struct 2013;49:27583.

    [11] Nguyen H, Mutsuyoshi H, Zatar W. Flexural behavior of hybrid composite beams.Transport Res Rec: J Transp Res Board 2013;2332:5363.

    [12] Nguyen H, Zatar W, Mutsuyoshi H. Hybridber-reinforced polymer girders topped

    with segmental precastconcrete slabs for accelerated bridge construction. TransportRes Rec: J Transp Res Board 2014;2407:8393.[13] Ollgaard JW, Slutter RG, Fisher JW. Shear strength of stud connectors in lightweight

    and normal-weight concrete. AISC Eng J 1971;8(2):5564.[14] AASHTO. AASHTO LRFD Bridge Design Specications. Washington DC: American As-

    sociation of State Highway and Transportation Ofcials; 2012.[15] CEN. 1994-2 Eurocode 4: Design of composite steel and concrete structures. Part 2:

    General Rules and Rules for Bridges; 2005.

    [16] CEN. 1994-4-4 Eurocode 4: Design of composite steel and concrete structures. Part1-1: General rules and rules for buildings; 2004.

    [17] AWS. Structural welding code-steel, AWS D1.1:2000. 17th ed. Miami, FL: AmericanWelding Society; 2000.

    [18] Anderson NS, Meinheit DF. Design criteria for headed stud group in shear: Part1Steel capacity and back edge effects. PCI J 2000;25:4675.

    [19] Oehlers DJ, Coughlan CG. The shear stiffness of stud shear connections in compositebeams. J Constr Steel Res 1986;6(4):27384.

    [20] Shim C-S, Lee P-G, Yoon T-Y. Static behavior of large stud shear connectors. EngStruct 2004;26(12):185360.

    [21] Xu C, SugiuraK. FEManalysis of failure development of group studs shear connector

    under effects of concrete strength and stud dimension. Eng Fail Anal 2013;35:34354.[22] Hegger J, Feldmann M, Rauscher S, Hechler O. Load-deformation behavior of shear

    connectors in high strength concrete subjected to static and fatigue loading. IABSESymposium Report Budapest 2006: Responding to Tomorrows Challenge in Struc-tural Engineering. IABSE; 2006. p. 1724.

    30 J.-S. Kim et al. / Journal of Constructional Steel Research 108 (2015) 2330

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