Jual shear connector 081281000409

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System shear connector digunakan sebagai aplikasi dalam konstruksi bangunan untuk menghasilkan kekuatan coran beton lebih kuat dan stabil sesuai dengan perhitungan engineering civil. Dalam hal ini ada 2 hal perhitungan kekuatan secara umum yaitu kekuatan kelengketan stud pada batang baja sesudah dilas. Dan yang kedua adalah kekuatan stud bolt yang digunakan.
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  • 1. Research Report Fatigue strength of shear connectors The researcher: En Xie The supervisor: Prof. Maria Isabel Brito Valente University of Minho, Guimarães, Portugal February, 2011
  • 2. Fatigue strength of shear connectors February 2011 II CONTENTS 1. Introduction.............................................................................................................. 1 1.1. Types of shear connectors........................................................................................... 1 1.2. Motivation and objectives........................................................................................... 3 2. Survey over endurance tests..................................................................................... 4 2.1. Tests by Slutter and Fisher......................................................................................... 4 2.1.1. Tests for headed studs.............................................................................................................4 2.1.2. Tests for channel connectors...................................................................................................9 2.2. Tests by Mainstone and Menzies.............................................................................. 10 2.3. Tests by Roderick and Ansourian ............................................................................ 11 2.4. Tests by Hallam ......................................................................................................... 12 2.5. Tests by Roik and Holtkamp .................................................................................... 13 2.6. Tests by Roik and Hanswille..................................................................................... 15 2.7. Tests by Naithani and Gupta.................................................................................... 17 2.8. Tests by Faust and Leffer ......................................................................................... 19 2.9. Tests by Shim and Lee............................................................................................... 20 2.10. Tests by Badie and Tadros ........................................................................................ 21 2.11. Tests by Seracino and Oehlers ................................................................................. 23 2.12. Tests by Lee and Shim............................................................................................... 25 2.13. Tests by Ahn and Kim............................................................................................... 27 2.14. Tests by Kwon and Engelhardt ................................................................................ 28 3. Survey over residual strength tests......................................................................... 30 3.1. Tests by Oehlers......................................................................................................... 30 3.2. Tests by Gattesco and Giuriani ................................................................................ 32 3.3. Tests by Bro and Westberg ....................................................................................... 33 3.4. Tests by Ahn and Kim with stud connectors........................................................... 34 3.5. Tests by Hanswille and Porsch................................................................................. 35 3.6. Tests by Ahn and Kim with Perfobond connectors ................................................ 40 4. Survey over slip tests............................................................................................... 42
  • 3. Fatigue strength of shear connectors February 2011 III 4.1. Tests by Hallam ......................................................................................................... 42 4.2. Tests by Gattesco and Giuriani ................................................................................ 43 4.3. Tests by Taplin ........................................................................................................... 43 4.4. Tests by Valente ......................................................................................................... 46 5. Discussion............................................................................................................... 47 5.1. Fatigue life calculation for studs.............................................................................. 47 5.2. Residual strength calculation for studs ................................................................... 50 5.3. Low cycle fatigue behavior of studs......................................................................... 52 5.4. Slip characteristics for studs under repeated loading............................................ 52 6. Conclusion.............................................................................................................. 54 7. References............................................................................................................... 56
  • 4. Fatigue strength of shear connectors February 2011 IV LIST OF FIGURES Figure 1 - Effect of shear connection on strain, bending and shear stresses ......................... 1  Figure 2 - Several types of connectors.................................................................................. 2  Figure 3 - Push-out-specimen used by Slutter and Fisher (1966) ......................................... 5  Figure 4 - Failure models of Shear studs under fatigue loading (Hallam, 1976) .................. 7  Figure 5 - S-N curves for stud test results by Slutter and Fisher........................................... 8  Figure 6 - Comparison of test results and the provision of AASHTO .................................. 8  Figure 7 - Failure models of channel connectors .................................................................. 9  Figure 8 - Comparison of test results by Slutter and Fisher and the equation (3)............... 10  Figure 9 - Push-out-specimen used by Mainstone and Menzies (Roik and Hanswille 1990) ..................................................................................................................................... 10  Figure 10 - Push-out-specimen used by Roderick and Ansourian (Roik and Hanswille 1990) ..................................................................................................................................... 12  Figure 11 - Push-out-specimen used by Hallam (Roik and Hanswille 1990) ..................... 12  Figure 12 - Push-out-specimen used by Roik and Holtkamp (Roik and Hanswille 1990) . 14  Figure 13 - S-N relationships of tests by authors in 1960s to 1970s................................... 14  Figure 14 - Push-out-specimen used by Roik and Hanswille (Roik and Hanswille 1990) . 16  Figure 15 - Test results by Roik and Hanswille (1989)....................................................... 16  Figure 16 - New Standard test specimen used by Naithani and Gupta (1988).................... 17  Figure 17 - Test results by Naithani and Gupta (1988) ....................................................... 18  Figure 18 - Push-out-specimen used by Faust and Leffer (2000) ....................................... 19  Figure 19 - Test results by Faust and Leffer (2000) ............................................................ 20  Figure 20 - Push-out-specimen used by Shim and Lee (2001) ........................................... 20  Figure 21 - Test results by Shim and Lee (2001) ................................................................ 21  Figure 22 - L-shaped specimen used by Badie and Tadros (2002) ..................................... 22  Figure 23 - Push-out-specimen used by Seracino and Oehlers (2003)................................ 24  Figure 24 - Test results by Seracino and Oehlers (2003) .................................................... 25  Figure 25 - Push-out-specimen used by Lee and Shim (2005) ........................................... 25  Figure 26 - Relation between stress range and fatigue life for large studs.......................... 26  Figure 27 - Push-out-specimen used by Ahn and Kim (2007)............................................ 27  Figure 28 – Test results by Ahn and Kim (2007) ................................................................ 28  Figure 29 - Post-installed shear connectors (Kwon and Engelhardt 2010)......................... 28  Figure 30 - Direct-shear test setup and reinforcing bar layout (Kwon and Engelhardt 2010) ..................................................................................................................................... 29  Figure 31 - Test results by Kwon and Engelhardt (2010).................................................... 29  Figure 32 - Push-out-specimen used by Oehlers (1990) ..................................................... 30  Figure 33 – Experimental interaction between strength and Endurance............................. 31 
  • 5. Fatigue strength of shear connectors February 2011 V Figure 34 - specimen details used by Gattesco and Giuriani (1996): (a) plan of specimen; (b) transversal section; (c) longitudinal section; (d) exploded view ........................... 32  Figure 35 - Push-out-specimen used by Bro and Westberg (2004)..................................... 34  Figure 36 - Test results by Bro and Westberg (2004).......................................................... 34  Figure 37 - Test results by Ahn and Kim (2007)................................................................. 35  Figure 38 - Push-out-specimen used by Hanswille and Porsch (2007)............................... 36  Figure 39 - Tests with multiple block of loading (Hanswille and Porsch 2007)................. 36  Figure 40 – Comparison of fatigue test results with the prediction in Eurocode 4............. 39  Figure 41 – Decrease of static strength versus lifetime due to high cycling loading.......... 40  Figure 42 – Comparison between the test results with the results of the lifetime prediction to Palmgren-Miner (Hanswille and Porsch, 2007)...................................................... 40  Figure 43 - Connector shape and push-out-specimen used by Ahn and Kim (2008).......... 41  Figure 44 –Test results of Perfobond connectors by Ahn and Kim..................................... 42  Figure 45 - Push-out specimens used by Taplin (1997) ...................................................... 44  Figure 46 - Push-out specimens used by Valente (2007) .................................................... 47  Figure 47 – Relationship between the experimental and theoretical fatigue life(Hanswille and Porsch, 2007)........................................................................................................ 50  Figure 48 – Comparison of the experimental and theoretical values of the reduced static strength by equation (15)............................................................................................. 51  Figure 49 – Comparison of the experimental and theoretical values of the reduced static strength by equation (16)............................................................................................. 51  Figure 50 – Evolution of slip depending on the cycles load range by Valente (2007)........ 54 
  • 6. Fatigue strength of shear connectors February 2011 VI LIST OF TABLES Table 1 - Test results of stud connectors by Slutter and Fisher (1966).................................. 5  Table 2 - Test results of channel connectors by Slutter and Fisher (1966)............................ 9  Table 3 - Test results of stud connectors by Mainstone and Menzies (1967)...................... 11  Table 4 - Test results by Roderick and Ansourian (1976) ................................................... 12  Table 5 - Test results by Hallam (1976) .............................................................................. 13  Table 6 - Test results by Roik and Holtkamp (1976)........................................................... 14  Table 7 - Test results by Roik and Hanswille (1989) .......................................................... 16  Table 8 - Test results by Naithani and Gupta (1988)........................................................... 18  Table 9 - Test results by Faust and Leffer (2000)................................................................ 19  Table 10 -Test results by Shim and Lee (2001)................................................................... 20  Table 11 - Test results by Badie and Tadros (2002) ............................................................ 22  Table 12 - Test results by Seracino and Oehlers (2003)...................................................... 24  Table 13 - Test results by Lee and Shim (2005).................................................................. 26  Table 14 - Test results by Ahn and Kim (2007)................................................................... 27  Table 15 - Test results by Kwon and Engelhardt (2010)..................................................... 29  Table 16 - Test results by Oehlers (1990)............................................................................ 30  Table 17 - Test results of Gattesco and Giuriani (1996)...................................................... 33  Table 18 - Test results by Bro and Westberg (2004)............................................................ 34  Table 19 - Test results by Ahn and Kim (2007)................................................................... 35  Table 20 - Number of specimens tested in each series and static ultimate strength............ 37  Table 21 - Test results by Hanswille and Porsch (S1~S4)................................................... 37  Table 22 - Test results by Hanswille and Porsch (S5~S6)................................................... 37  Table 23 - Test results of Perfobond connectors by Ahn and Kim (2008) .......................... 41  Table 24 - Test results of stud connectors by Hallam (1976) .............................................. 42  Table 25 - Tests result by Gattesco and Giuriani (1997)..................................................... 43  Table 26 - Rate of slip growth for all symmetric cyclic tests.............................................. 44  Table 27 - Rate of slip growth for all unidirectional cyclic tests......................................... 45  Table 28 - Slip results by Valente (2007) ............................................................................ 47  Table 29 - Design models for the fatigue life of shear studs............................................... 48  Table 30 -Coeddicient in equation (18) for the rate of slip growth as determined by......... 53 
  • 7. Fatigue strength of shear connectors February 2011 VII LIST OF SYBOLS fc - cylinder strength of the concrete (MPa) fy - yield strength of shear connector material (MPa) fu - tensile strength of shear connector material (MPa) d - diameter of steel stud connector (mm) L - length of channel connector or Perfobond connector (mm) Pmax - the maximum load per connector(kN) Pmin - the minimum load per connector(kN) ΔP - Pmax-Pmin, load range (kN) Δτ - ΔP /A(A-shear area of connector), stress range(MPa) N - number of cycles Ne - experimental fatigue life Nf - theoretical fatigue life Δq - stress range of channel connector, N/mm of one channel Pu - ultimate strength per connector due to static loading (kN) Ps - residual static strength per connector after certain cycling numbers (kN) smax - the maximum slip per cycle (mm) smin - the minimum slip per cycle (mm) δ - slip per cycle (mm) m, k - exponents in expression for fatigue life K1 K2 - coefficients
  • 8. Fatigue strength of shear connectors February 2011 1 / 58 1. Introduction 1.1. Types of shear connectors Shear connection is essential for steel-concrete composite structures, as shown in Figure 1, only when the interface between steel beam and concrete slab is eliminated, the two components can act together as a composite unit. Figure 1 - Effect of shear connection on strain, bending and shear stresses Since 1940s, several types of shear connectors have been proposed and used in composite structures (Figure 2), such as headed stud connector, channel connector, block connector with hoops, post-installed shear connector, T connector, Perfobond, T-Perfobond and Crestbond (CR connector). The most well-known and used connector is the headed stud, developed during the 40’s by Melson Stud Welding Company. These connectors are industrially produced and are available in various diameters, usually varying from 6 to 23 mm, and various heights, that can go from 30 to 500 mm. The main advantage of this connector are as the stud welding is fast, it anchors well in concrete and it is easy to dispose the reinforcement through the slab, between the studs. Some disadvantage can also be pointed out as it needs high energetic resources to work, fatigue problems can also occur for service load level. Since the maximum shear force that can be resisted by a stud is relatively low, other types of connector with higher strength have been developed in the early times, primarily for use in bridges as block connector with hoops and channel connector. Strain Bending stress Shear stress Strain Bending stress Shear stress (a) No connection (b) Full connection Beam section Elastic stress Ultimate Plastic stress
  • 9. Fatigue strength of shear connectors February 2011 2 / 58 (a) Headed stud (b) Channel (c) block with hoops (d) Post-installed shear connectors (Gunup, 2010) (e) T (Valente, 2007) (f) Perfobond (Valente, 2007) (g) T-Perfobond (Vianna, 2008) (h) Crestbond (Veríssimo, 2006) Figure 2 - Several types of connectors The post-installed shear connectors are used to develop the composite action in existing non-composite floor systems, in a number of older bridges built before the 1970’s. The T connector can be produced with different shapes, but usually is made from a commercial profiled steel section. The T shape has a larger contact area than a single strip, so the shape is appropriate to prevent vertical separation between the steel beam and the concrete slab. In terms of fatigue, T connectors show the same fatigue problems as studs, as they present important deformation for service loadings, and they need to develop high deformation to mobilize the
  • 10. Fatigue strength of shear connectors February 2011 3 / 58 maximum load. The Perfobond rib shear connector was developed by a German office in the late 1980’s, moved by the unsatisfactory behavior of shear studs that result from fatigue problems. Perfobond connectors can be produced in large scale with different shapes and sizes, they can easily be welded without special equipment at site or at factory, and a significant number of studs can be replaced by a smaller number of Perfobond ribs, as this connector shows a very high load bearing capacity. T-Perfobond connector derives from the Perfobond connector by adding a flange to the plate, acting as a blocking. This kind connector could combine the large strength of a block type connector with some ductility and uplift resistance arising from the holes at the Perfobond connector web. Because of combination, it is complicated to calculate the shear strength. It might be applied only in some specific projects. The principal disadvantage of Perfobond is the difficulty of placing the transversal bottom slab reinforcement. To avoid this disadvantage, some similar improved types of connectors like Crestbond also called CR connector have been invented and studied, considering open apertures on the plates. 1.2.Motivation and objectives Nowadays steel and concrete composite beams are widely applied in structures mainly subjected to dynamic loads, such as railway and road bridges exposed to traffic l
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