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    • TOUGH FIX HYPER for Anti – Stripping
      TOUGH FIX HYPER for Anti – Stripping

      Tough Fix Hyper is an additive which improves the adhesion between aggregate and asphalt, the anti-stripping performance of asphalt mixture.

      Price in Vietnam Dong per Kilogram, Packing in 15kg / bag.

       

      Origin Japan
      Description Additive in slender shape (solid), yellow color, easily dissolved into asphalt concrete.
      Uses Improve the adhesion between aggregate and asphalt, does not impact on the asphalt properties.
      Usage Directly apply to the mixing tank of the asphalt plant or premix with asphalt at the specified ratio.
      Storage Store in a cool & dry place.

       

    • TAFPACK-SUPER (TPS) for Porous Asphalt Pavement
      TAFPACK-SUPER (TPS) for Porous Asphalt Pavement

      “TAFPACK-Super”, often abbreviated asTPS”, is a modifier for high-viscosity modified asphalt used for porous asphalt mixture.

      Price in Vietnam Dong per Kilogram, Packing in 20kg / bag.

       

         Origin Vietnam
         Description Additive in granules, yellow or black, easily dissolved into asphalt concrete.
         Uses Increase the viscosity of asphalt, increase the softening temperature and create stable bonds.
         Usage Directly apply TPS to the mixing tank of the asphalt plant at the specified ratio.
         Storage Store in a cool & dry place.

       

    • TAFPACK-PREMIUM (TPP) for Anti – Rutting of Pavement
      TAFPACK-PREMIUM (TPP) for Anti – Rutting of Pavement

      Tafpack-Premium”, often abbreviated asTPP”, is an asphalt modifier to improve the rutting resistance.

      Price in Vietnam Dong per Kilogram, Packing in 25kg / bag.

         Origin Vietnam
         Description Additive in granules, white color, easily dissolved into asphalt concrete.
         Usage Directly apply TPP to the mixing tank of the asphalt plant at the specified ratio.
         Storage Store in a cool & dry place.

       

    • PROMENADE – Resin bound gravel pavement
      PROMENADE – Resin bound gravel pavement

      The High-quality Epoxy Glue which is used for Resin bound gravel pavement.

       

      Origin Japan
      Description Liquid form stored in 4 separate containers. (The main resin and amine type hardener).
      Uses Being an adhesion layer and creating bonds between gravels.
      Usage Mixing the main resin and amine type hardener, then applying on the pavement.
      Storage Store in a cool & dry place.

       

    • STP-VN for Semi – Flexible Pavement
      STP-VN for Semi – Flexible Pavement

      STP-VN is an cement modifier used in cement mortar mixture for Semi – Flexible Pavement.

       

      Origin Japan
      Description

       Additive in powder with gray color (same color as Cement PCB40) or red color.

      Uses Cement modifier for crack resistance, bending resistance. Pour the mortar into the voids of the asphalt mixture to form Semi – Flexible Pavement.
      Usage Mixing Cement PCB40 + Clean water + STP-VN on site at the specified ratio.
      Storage Store in a cool & dry place.

       

    • TAF-EPOXY & HYPER-PRIMER for Steel Deck Slab
      TAF-EPOXY & HYPER-PRIMER for Steel Deck Slab

      Epoxy Resin for asphalt mixture                & Epoxy Asphalt Mixture on steel plate deck   TAF-EPOXY & TAF-MIX・EP   TAIYU KENSETSU CO., LTD.  KINDAI KASEI CORPORATION CO., LTD. PREFACE Recently, construction works of the long-span-bridge with a steel plate deck are increasing along with the development of industry and economy. That is because the […]

    Analysis and Epoxy Asphalt

    Structural Analysis of Asphalt Pavement

     

    on Steel Plate deck and Epoxy Asphalt Mixture

     

    Dr. Nakanishi Hiromitsu, Director, Global team, Taiyu

     

    Prof. Tran Thi Kim Dang, UTC

     

    Dr. Nguyen Quang Phuc, UTC

     

    Mr. Kato Akihiro, Vietnam Office, Taiyu

     

    ABSTRACT: This report is concerning to asphalt pavement on steel plate deck. Now, steel plate
    deck bridge is increasing along with economic development of the country. However, some kinds of severe deterioration, rutting, longitudinal cracking, slippage from steel plate deck and others, are arising in this pavement. At present, there are two steel plate deck in Vietnam, Thang Long bridge
    in Hanoi and Thuan Phuoc bridge in Danang. Longitudinal cracking and slippage from steel plate deck are arising on Thang Long bridge while slippage from steel plate deck seems to occur on Thuan Phuoc bridge. Such deterioration is the representative characteristics as the damage of the asphalt pavement on steel plate deck. However, so far, there have been no answers to the question about why such deterioration would arise in the pavement on steel plate deck. In this report, at first, a structural model is proposed as a simulation method to calculate stress, strain,
    and shear stress which would generate in asphalt pavement on a steel plate deck. Secondly, epoxy
    asphalt mixture and epoxy type tack coat material are introduced as the suitable materials to endure the stress and strain which would be generated in the pavement on steel plate deck.

    1. INTRODUCTION

    Asphalt pavement on steel plate deck has been subjected to various deterioration, longitudinal cracking, slippage from the steel plate deck, rutting, stripping, blistering, and others, as shown in photographs. These problems are deeply concerning to the structure of pavement on steel plate deck.

     

    However, there were no research reports on the structural design for the pavement on steel plate deck. Longitudinal cracking must be influenced by longitudinal ribs just below steel plate and slippage should be related to the shear stress arising between steel plate and pavement. In spite of that, there have never been methods to simulate about how large strain or stress would work in the pavement on steel plate deck. As a result, we didn’t know what kinds of property of the asphalt mixture would be able to lead to the long term durability of the pavement on steel plate deck.

    2. ON-SITE STRAIN INVESTIGATION

    MIKAWA Port Bridge which has steel plate deck with the length of 300m has been constructed in Japan in 1979, and epoxy asphalt mixture has been adopted as a pavement material. Furthermore, epoxy resin has been used as a tack coat. In fact, this bridge has been opened to the general traffic in 1982. We have carried out some investigations on site, like a strain measurement by loading a dump truck, before being opened to general traffic. And, I‘d like to add that this pavement has been available with no maintenance for this 35 years although some cracking have arisen.

    2.1. Wheel load

    The data of the dump truck used for the on-site investigation are as shown in Table 2.1.

    2.2. Location of strain measurement

    The location of strain gauges and loading positions were set as shown in Fig. 2.1 and Fig. 2.2. Further detail information would be obtained in reference [1]

    3. COMPOSITE BEAM CONSISTING OF SURFACE
    COURSE, BINDER COURSE, AND STEEL PLATE DECK

    The calculation shall be based on “Euler’s Assumption” that the plane cross section shall incline with keeping plane after receiving bending force. The cross section model of the three layers structure is as shown in Fig. 3.1

     

    Here, it is assumed that the interface between surface layer and binder layer is perfectly bonded and the interface between the binder layer and the steel plate is un-perfectly bonded. Regarding the degree of bonding, the bonding coefficient “t” from 0 to 1,0 is defined, the bonding coefficient “t” of 1,0 provides the perfect bonding while the bonding coefficient “t” of 0 provides the perfect non-bonding. Furthermore, in case of perfect un-bonding, the two (2) neutral axes must generate at the position of the neutral axis of the composite layer of surface layer and binder layer and the neutral axis of the steel plate, respectively. The distributions of strain around two (2) neutral axes must be based on “Euler’s Assumption” and the slopes of the distributions must be same. The position of the neutral axis of the composite layer of the surface layer and the binder layer is h0 from the top of surface and h0 can be derived by Equation (1).


    The neutral axis of the steel plate generates at the position of (h3/2). If the distance between two (2) neutral axes would be (T), (T) can be expressed as follows using the bonding coefficient, (t)

    If the formula of the strain occurring around the first axis is expressed by ε = ky and the position of the origin is y = 0, the formula of the strain occurring around the second axis can be expressed by ε = k(y – T). The equation of equilibrium of the fiber stress at the situation can be shown as follows;

    3.1. Distribution of strain and stress occurring in
    three layers composite beam

    The strain and stress occurring in the three (3) layers composite beam can be shown as follows using the moment of inertia area, (J). (The position of the neutral axis is coordinate origin).

    Shear stress occurring in three (3) layers composite beam need to be considered. In general, the shear stress can be obtained using the following formula.

    Regarding the detail of expansion of equations, there is precise explanation in reference [1]. Here, the final equations are shown.
    (In case of surface course, -h ≦ y ≦ -h + h1)

    4. PROPOSAL OF STRUCTURAL MODEL FOR
    PAVEMENT ON STEEL PLATE DECK

    4.1. Behavior of Pavement on Steel Plate Deck


    Behavior of the pavement on steel plate deck is thought as shown in Fig. 4.1. The supports on the ribs at both sides of tire is not fully fixed but the rotation would be restrained in proportion to the deflection slope. And, regarding the support between double tires, the relative displacement would arise.

    4.2. Beam Model for Pavement on Steel Plate Deck.

    If considering the behavior mentioned above, structural model is simplified as shown in Fig. 4.2. The characteristics of this Model are to have an elastic hinge at support A and to have an elastic support at support B. Therefore, the vertical direction movement in proportion to the reaction at support B would be allowed with this Model in addition that the free rotation at support A is restrained by the elastic hinge. The adoption of the elastic support at B support would result in lowering the whole rigidity of this structure.

    This Model is secondary statistically indeterminate beam. There are some calculation approaches, the structural calculation carried out here is based on Principle of virtual work. [2] Bending moments at each condition are shown in Table 4.1. Here, the influences by normal axial force and shear force which would be subjected to the beam are ignored.

    Strains on the undersurface of steel plate, which have been measured on March, 1982, and calculated strains are shown in Fig. 4.3. In fact, coefficient, k and f, are set so that the simulation curve could meet with actually measured data. As aresult, k, f, and relevant φ and η are a shown in Table 4.2.

    On the same conditions as shown in Fig. 4.3 and Table 4.2, the distribution of tensile strains on the surface of asphalt pavement and the distribution of shear stress which would work in the structure are shown in Fig. 4.4 and Fig. 4.5, respectively.

    According to the simulation, in spite of cold season and relatively small wheel load of 5,05 tons, larger strain of about 100kg/cm2 works just above longitudinal rib. Furthermore, the shear stress as large as 11kg/cm2 is generating on the interface between pavement and steel plate. Regarding the coefficient of K and F, they represent the rigidity of the structure including pavement properties. If  the thickness of the steel plate deck is thin or the temperature of the asphalt pavement is high, the

    rigidity of the whole structure should become smaller. In my idea, K would be from 0,02 to 0,035 and F would be 0,0003 to 0,0006, but further research would be needed. However, the most important thing is that the strain which would generate on the pavement surface or the shear stress which would generate between steel plate deck would be able to be calculated if employing this Model.

    5. PAVEMENT ON STEEL PLATE DECK &
    MATERIALS TO BE USED ON THANH LONG BRIDGE

    According to the information on Thanh Long Bridge in Hanoi, the thickness of steel plate deck is 1,4cm, the  pavement has been paved by SMA using PMB 3 and the total thickness of two layers is 7cm. And, Bond Coat has been applied as a tack-coat between steel plate and pavement. 

     

    Based on the information about Thanh Long Bridge, we simulated the strain and the shear stress which would generate. Regarding the simulation, the calculation conditions will be set so as to meet actual situation in Thanh Long Bridge. The calculation results are shown in Fig. 5.1 and 5.2. Note: Simulation conditions are; Wheel road: 10 tons, Elastic modulus of SMA with PMB3: 10,000kg/cm2, Perfect bonding at interface

    Simulation results show the maximum tensile strain above rib is about 1500*10-6. Furthermore, shear stress between steel plate deck and pavement is about 12kg/cm2. These simulation results would suggest that the pavement on Thanh Long Bridge is being suvjected to the severe stress and strain situation. Therefore, in order to prevent from various deteriolation like longitudinal cracking and slippage, the materials which would be able to endure such strain and stress situation should be employed on Thanh Long Bridge. In our experiences, only Epoxy asphalt mixture and Epoxy type tack-coat would be able to endure such severe conditions. We can not give you enough explanation due to the paper length limitation, we’d like you to refer to reference [3]. Here, only the data on fatigue characteristics of epoxy asphalt mixture is introduced in Fig. 5.3

    Fig. 5.3 Fatigue test results for various asphalt mixture

     

    As far as we look at Fig. 5.3, the fatigue life of Epoxy asphalt mixture is about 10 times longer than the conventional asphalt mixture. Furthermore, because the elastic modulus of the epoxy asphalt mixture is relatively higher than the conventional one, the strain generated should become smaller.


    Photo. 5.1: Spray of Epoxy type tack-coat.

    Regarding the shear stress generated at the interface between steel plate and pavement, if conventional tackcoat would be employed, slippage like on Thanh Long Bridge should arise because shear stress itself is very big. Against this problem, we would like to recommend Epoxy
    type tack-coat because it exerts very strong bonding strength more than 28kg/cm2 [3].

    Acknowledgement
    We appreciate this conference secretariats for giving us an opportunity to present on the structural simulaion about the pavement on Steel Plate Deck, which has not been tackled so far.
    References
    [1]. H. Nakanishi (March 2016), Structural design
    Method for the Pavement on Steel Plate Deck, UTC seminar.
    [2]. For example, R. Arai (1968), Applied
    Mechanics, Gihodo.
    [3]. Taiyu Kensetsu Co., Ltd., TAF-EPOXY & TAF-MIX EP,
    Technical brochure