Journal articles: 'Pullout test'

1

Park, Jong-Beom, Daehyeon Kim, Si-Bong Yang, and Jang-Heung Kim. "Pullout Characteristics of Geosynthetics Reinforced Earth Using Multilayer Spreading Pullout Test." Advances in Materials Science and Engineering 2017 (2017): 1–11. http://dx.doi.org/10.1155/2017/9485826.

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Pullout test equipment for examining pullout characteristics in a reinforced earth structure is relatively larger than direct shear testing machines and requires much time and expenses in preparing samples. Moreover, because of irregular stress distributions with respect to the length of reinforcements, it is difficult to analyze pullout test results. In this study, we developed a multilayer spreading pullout apparatus enabling the pullout test in the order of a top stage, middle stage, and bottom stage with different loads once a ground model is prepared, suggesting an efficient method of a multilayer spreading pullout test. The pullout test is carried out at least three times with the prepared ground model while changing confining loads. Jumunjin sand was used to verify the developed pullout test apparatus and to analyze pullout characteristics of each reinforcement. The analysis reveals that the difference between angles of pullout friction is approximately 0.86 to 1.3° which is distributed within the error range of a pullout test. As a result, the multilayer spreading pullout apparatus is applicable as a new pullout apparatus, and the suggested method of multilayer spreading pullout test is identified as a pullout test technique efficiently to obtain pullout parameters.

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Teerawattanasuk, Chairat, Dennes T. Bergado, and Warat Kongkitkul. "Analytical and numerical modeling of pullout capacity and interaction between hexagonal wire mesh and silty sand backfill under an in-soil pullout test." Canadian Geotechnical Journal 40, no. 5 (October 1, 2003): 886–99. http://dx.doi.org/10.1139/t03-038.

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During the pullout test, the pullout clamping system was modified and installed inside the pullout box with confinement from the fill material, hereinafter called the in-soil pullout test, which significantly reduced the necking phenomenon and the displacements mobilized during the pullout test. Subsequently, an analytical model was developed to predict the in-soil pullout resistance. In addition, a numerical modeling analysis, under the three-dimensional stress field conditions using the FLAC3D (fast Lagrangian analysis continua) program, was carried out to simulate the behavior of in-soil pullout tests. The laboratory in-soil pullout test results were then compared with the corresponding data obtained from the analytical and numerical modeling methods. The in-soil pullout resistance was greater than the corresponding result from previous pullout tests wherein the clamping system was conventionally installed outside the pullout box. The predicted pullout resistance results from FLAC3D agreed reasonably with the results from laboratory tests and with the results from the analytical modeling. The interaction coefficients, R, applied in the finite difference modeling of in-soil pullout tests were 0.90 and 0.65 for zinc-coated and polyvinyl chloride (PVC) coated hexagonal wire meshes, respectively. The predicted and measured pullout resistance of zinc-coated hexagonal wire mesh is approximately 20% greater than that of PVC-coated hexagonal wire mesh at the same applied normal pressure, because of the higher stiffness, EA, and higher shear stiffness, ks, of the zinc-coated mesh.Key words: hexagonal wire mesh, in-soil pullout test, pullout resistance, analytical modeling, numerical modeling.

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Park, Kyungho, Daehyeon Kim, Jongbeom Park, and Hyunho Na. "The Determination of Pullout Parameters for Sand with a Geogrid." Applied Sciences 11, no. 1 (December 31, 2020): 355. http://dx.doi.org/10.3390/app11010355.

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The concept of designing mechanically stabilized earth (MSE) walls is divided into internal and external stability review methods, and one of the design factors required in internal stability analysis is the frictional characteristics between soil and geogrids for civil engineering applications. Typical methods for evaluating the frictional characteristics between soil and geogrids include the direct shear test and pullout test. It is desirable to apply the pullout test to geogrid reinforcements for pulling out geogrids embedded in soil, to measure both the surface-frictional force and passive resistance at the same time. Pullout parameters can be significantly affected by confining the stress and tensile strength of reinforcements. In general, the pullout parameters tend to be overestimated for low confining stresses in the pullout test, and underestimated for high confining stresses. Therefore, to address these issues, this study aims to evaluate the influence of the confining stress and the tensile strength of a geogrid reinforcement in the pullout test, and to propose a reasonable method for obtaining practical pullout parameters. Based on the pullout tests, the maximum pullout force depending on the tensile strength of the geogrid reinforcement was measured for one-third of the reinforcement tensile strength, and it was ruptured when pullout force greater than the maximum pullout force was exerted. Furthermore, it was observed that, in the reinforcement pullout test, pullout force was measured in the whole area of the reinforcement at a confining stress smaller than one-half of the tensile strength of the grid. As a result, the effective confining stress method considering only the confining stress at which the reinforcement is fully pulled out to develop the pullout characteristics can be a practical method for obtaining pullout parameters without regard to the reinforcement tensile strength.

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Tan, S. A., P. H. Ooi, T. S. Park, and W. L. Cheang. "Rapid Pullout Test of Soil Nail." Journal of Geotechnical and Geoenvironmental Engineering 134, no. 9 (September 2008): 1327–38. http://dx.doi.org/10.1061/(asce)1090-0241(2008)134:9(1327).

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Gurung, N., Y. Iwao, and M. R. Madhav. "Pullout test model for extensible reinforcement." International Journal for Numerical and Analytical Methods in Geomechanics 23, no. 12 (October 1999): 1337–48. http://dx.doi.org/10.1002/(sici)1096-9853(199910)23:12<1337::aid-nag35>3.0.co;2-h.

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Krenchel, H., and S. P. Shah. "Fracture analysis of the pullout test." Materials and Structures 18, no. 6 (November 1985): 439–46. http://dx.doi.org/10.1007/bf02498746.

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Kwon, Soon-Jang, and Yun-Tae Kim. "Pullout Characteristics of Waste Fishing Net Reinforced Bottom Ash using Pullout Test." Journal of the Korean Geosynthetic Society 12, no. 4 (December 30, 2013): 57–66. http://dx.doi.org/10.12814/jkgss.2013.12.4.057.

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Xuan, Wei Hong, Yan Wang, and Yu Zhi Chen. "Regression Analysis on Bonding Test of Polypropylene Fiber." Applied Mechanics and Materials 638-640 (September 2014): 1378–82. http://dx.doi.org/10.4028/www.scientific.net/amm.638-640.1378.

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Base on the data that gained from pullout test of Polypropylene fiber, multi-factor regression analysis considering water cement ratio and age of cement matrix, length and angle of embedded fiber was carried out. Then, a practical function of pullout force-displacement was proposed, which is well agreed with the test results.

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Aycan, Mehmet Fatih, Tolga Tolunay, Teyfik Demir, Mesut Emre Yaman, and Yusuf Usta. "Pullout performance comparison of novel expandable pedicle screw with expandable poly-ether-ether-ketone shells and cement-augmented pedicle screws." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 231, no. 2 (January 18, 2017): 169–75. http://dx.doi.org/10.1177/0954411916687792.

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Aim of this study is to assess the pullout performance of various pedicle screws in different test materials. Polyurethane foams (Grade 10 and Grade 40) produced in laboratory and bovine vertebrae were instrumented with normal, cannulated (cemented), novel expandable and normal (cemented) pedicle screws. Test samples were prepared according to the ASTM F543 standard testing protocols and surgical guidelines. To examine the screw placement and cement distribution, anteriosuperior and oblique radiographs were taken from each sample after insertion process was completed. Pullout tests were performed in an Instron 3369 testing device. Load versus displacement graphs were recorded and the ultimate pullout force was defined as the maximum load (pullout strength) sustained before failure of screw. Student’s t-test was performed on each group whether the differences between pullout strength of pedicle screws were significant or not. While normal pedicle screws have the lowest pullout strength in all test materials, normal pedicle screws cemented with polymethylmethacrylate exhibit significantly higher pullout performance than others. For all test materials, there is a significant improvement in pullout strength of normal screws by augmentation. While novel expandable pedicle screws with expandable poly-ether-ether-ketone shells exhibited lower pullout performance than normal screws cemented with polymethylmethacrylate, their pullout performances in all groups were higher than the ones of normal and cannulated pedicle screws. For all test materials, although cannulated pedicle screws exhibit higher pullout strength than normal pedicle screws, there are no significant differences between the two groups. The novel expandable pedicle screws with expandable poly-ether-ether-ketone shells may be used instead of normal and cannulated pedicle screws cemented with polymethylmethacrylate due to their good performances.

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Fei, Jianbo, Yuxin Jie, Haipeng Wu, and Ting Zhou. "Laboratory pullout test study on the influence zone of geosynthetics." Journal of Engineered Fibers and Fabrics 15 (January 2020): 155892502090667. http://dx.doi.org/10.1177/1558925020906674.

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Conventional pullout test devices are mainly designed to measure the shear strength indices of the geosynthetics–soil interface. This article introduces a new model container to study the influence zone of geosynthetics in pullout test. Several basic image processing methods were employed to analyze the grain motion of two gravel compositions in pullout tests. The trajectories of grains in the gravel differ at different heights; specifically, a more active motion was observed if the grain was closer to the geosynthetics. Moreover, grains were found to move not only horizontally but also vertically as well as to rotate on pulling out the geosynthetics. The range of a grain on the move is almost constant during the pullout and determines the influence zone of the geosynthetics. Image processing revealed that the influence zone was eight times the average grain size above the geosynthetics and 4–5 times the average grain size below the geosynthetics. The boundary condition thus significantly affects the influence zone.

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Shahin, Mohamed A., and Mark B. Jaksa. "Pullout capacity of small ground anchors by direct cone penetration test methods and neural networks." Canadian Geotechnical Journal 43, no. 6 (June 1, 2006): 626–37. http://dx.doi.org/10.1139/t06-029.

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Marquees are temporary light structures that are connected to the ground by small anchors that act in tension and are designed to resist uplift forces. Due to the temporary nature of these structures, little, if any, attention is given to the pullout capacity of the anchors used to secure them. Failures of such structures are not rare and have resulted in deaths and tens of thousands of dollars of damage. This paper reports on a series of 119 in situ anchor pullout tests conducted on rough mild steel anchors of various lengths, cross-sectional shapes, and areas. Comparison tests are carried out to investigate the impact of the factors affecting the pullout capacity of small anchors. Six methods that determine the axial pile capacity directly from cone penetration test (CPT) data are presented and used to calculate the pullout capacity of small ground anchors. The capacities obtained from these CPT-based methods are compared with predictions from a recently developed artificial neural network (ANN) model. The actual pullout loads are compared with predictions from the CPT and ANN methods, and statistical analyses are carried out to evaluate and rank their performance. The results indicate that the ANN-based method provides superior predictions of the pullout capacity of small ground anchors, whereas the Schmertmann method provides the best performance of the CPT-based techniques examined.Key words: ground anchors, pullout capacity, cone penetration test, artificial neural networks.

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12

Bergado, D. T., K. C. Macatol, N. U. Amin, J. C. Chai, M. C. Alfaro, and L. R. Anderson. "Interaction of lateritic soil and steel grid reinforcement." Canadian Geotechnical Journal 30, no. 2 (April 1, 1993): 376–84. http://dx.doi.org/10.1139/t93-032.

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Laboratory and field pullout tests were carried out to study the interaction of welded steel grid reinforcements embedded in lateritic residual soil backfill. The laboratory pullout tests were conducted on various reinforcement sizes, mesh geometries, normal pressures, and compaction conditions of the backfill material. Field pullout tests were conducted at representative overburden, field-moisture, and density conditions. From the test results, it was found that the longitudinal members yielded frictional resistance from 8 to 15% of the total grid pullout resistance. Thus, the major contribution to the pullout resistance of grid reinforcements consists of the passive resistance mobilized in front of the transverse members. The maximum pullout resistance is shown by a bilinear curve which displayed similarity with the failure envelope from direct shear tests of the backfill material. This bilinear envelope reinforced the previous observation regarding the effect of particle breakage phenomenon inherent to lateritic residual soils subjected to high normal pressures. Comparisons between laboratory and field pullout resistances and between the predicted passive resistance and the laboratory test data are also presented. Key words : reinforcement, laboratory test, earthfill, compaction, friction resistance.

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13

Bakeer, Reda M., Ahmed H. Abdel-Rahman, and Phillip J. Napolitano. "Geotextile friction mobilization during field pullout test." Geotextiles and Geomembranes 16, no. 2 (April 1998): 73–85. http://dx.doi.org/10.1016/s0266-1144(97)10024-3.

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14

Yang, Qing-Sheng, Qing-Hua Qin, and Xi-Rong Peng. "Size effects in the fiber pullout test." Composite Structures 61, no. 3 (August 2003): 193–98. http://dx.doi.org/10.1016/s0263-8223(03)00066-7.

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15

Turusov, R. A., A. S. Freidine, and V. N. Kestelman. "Mechanical Analysis of “Pullout” Adhesion Test Method." International Journal of Polymeric Materials 33, no. 1-2 (April 1996): 103–13. http://dx.doi.org/10.1080/00914039608028612.

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16

Tastani, S. P., and S. J. Pantazopoulou. "Direct Tension Pullout Bond Test: Experimental Results." Journal of Structural Engineering 136, no. 6 (June 2010): 731–43. http://dx.doi.org/10.1061/(asce)st.1943-541x.0000159.

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17

Mallick, S. B., H. Zhai, S. Adanur, and D. J. Elton. "Pullout and Direct Shear Testing of Geosynthetic Reinforcement: State-of-the-Art Report." Transportation Research Record: Journal of the Transportation Research Board 1534, no. 1 (January 1996): 80–90. http://dx.doi.org/10.1177/0361198196153400112.

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The frictional characteristics of a soil-geosynthetic interface can be determined by direct shear and pullout tests. The direct shear test is commonly conducted according to ASTM standard D5321. However, at present there is no ASTM method for pullout testing of geosynthetics. During the past 10 years different researchers have obtained a wealth of information from direct shear and pullout tests of geosynthetics. A critical analysis of direct shear and pullout tests and an evaluation of the effects of fundamental material and testing parameters on test results are presented.

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18

Tsiotsias, Konstantinos, and Stavroula J. Pantazopoulou. "Analytical Investigation on the Effect of Test Setup on Bond Strength." CivilEng 2, no. 1 (January 1, 2021): 14–34. http://dx.doi.org/10.3390/civileng2010002.

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Experimental procedures used for the study of reinforcement to concrete bond have been hampered for a long time by inconsistencies and large differences in the obtained behavior, such as bond strength and mode of failure, depending on the specimen form and setup used in the test. Bond is controlled by the mechanics of the interface between reinforcement and concrete, and is sensitive to the influences of extraneous factors, several of which underlie, but are not accounted for, in conventional pullout test setups. To understand and illustrate the importance of specimen form and testing arrangement, a series of computational simulations are used in the present work on eight distinct variants of conventional bar pullout test setups that are used routinely in experimental literature for the characterization of bond-slip laws. The resulting bond strength increase generated by unaccounted confining stress fields that arise around the bar because of the boundary conditions of the test setup is used to classify the tests with respect to their relevance with the intended use of the results. Of the pullout setups examined, the direct tension pullout test produced the most conservative bond strength results, completely eliminating the contributions from eccentricity and passive confinement.

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Aycan, Mehmet Fatih, Mesut Emre Yaman, Yusuf Usta, Teyfik Demir, and Tolga Tolunay. "Investigation of toggling effect on pullout performance of pedicle screws." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 232, no. 4 (February 2, 2018): 395–402. http://dx.doi.org/10.1177/0954411918755417.

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Objective of this study is to assess the pullout performance of various pedicle screws in different test materials after toggling tests comparatively. Solid core, cannulated (cemented), novel expandable and solid-core (cemented) pedicle screws were instrumented to the polyurethane foams (Grade 10 and Grade 40) produced in laboratory and bovine vertebra. ASTM F543 standard was used for preparation process of samples. Toggling tests were carried out. After toggling test procedures, pullout tests were performed. Load versus displacement graph was recorded, and the ultimate pullout force was defined as the maximum load (pullout strength) sustained before failure of screw. Anteriosuperior and oblique radiographs were taken from each sample after instrumentation in order to examine screw placement and cement distribution. The pullout strength of pedicle screws decreased after toggling tests with respect to the initial condition. While the cemented solid-core pedicle screws had the highest pullout strength in all test materials, they had the highest strength differences. The cemented solid-core pedicle screws had decrement rates of 27% and 16% in Grade 10 and Grade 40, respectively. There are almost same decrement rate (between 5.5% and 6.5%) for all types of pedicle screws instrumented to the samples of bovine vertebra. The pullout strengths of novel expandable pedicle screws in both of early period and after toggling conditions were almost similar, in other words, the decrement rates of it were lower than other types. According to the data collected from this study, polymethylmethacrylate augmentation significantly decreases pullout strength following the toggling loads. Higher brittleness of cured polymethylmethacrylate has adverse effect on the pullout strength. Although augmentation is an important process for enhancing pullout strength in early period, it has some disadvantages for preserving stabilization in a long time. Expandable pedicle screw with polyetheretherketone shell may be good alternative to polymethylmethacrylate augmentation on both primer stabilization and long-term loading application with toggling.

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Bang, S., S. Boonyong, and Y. Cho. "Field Installation and Pullout Test of Embedded Suction Anchors." Transportation Research Record: Journal of the Transportation Research Board 1936, no. 1 (January 2005): 117–23. http://dx.doi.org/10.1177/0361198105193600114.

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The field installation and pullout tests of an embedded suction anchor were conducted inside the Okpo Harbor located along the southeastern coast of South Korea in 2003. The embedded suction anchor was made of steel with an outside diameter of 1.91 m, length of 2.5 m, and thickness of 3 cm. It was installed by a 9.25-m-long suction pile attached at the top of the anchor. During installation of the embedded suction anchor and retrieval of the suction pile, the water pressure inside the suction pile versus the pile embedded length relationship was carefully measured. In addition, during the embedded suction anchor pullout test, the load versus anchor vertical displacement relationship was measured. The measured pullout capacity was then compared with the analytical prediction. The analytical solution was selected from various available solutions of deeply embedded plate anchors available from the literature through detailed comparisons with the results from geotechnical centrifuge model tests on embedded suction anchors. Comparison indicated that the predicted embedded suction anchor resistance matched reasonably well with the field test result.

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Dai, Ying, Xing Ji, Lin Ye, and Yiu Wing Mai. "Specimen Design for IFSS Measurement in Fiber Pullout Test." Key Engineering Materials 312 (June 2006): 149–54. http://dx.doi.org/10.4028/www.scientific.net/kem.312.149.

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Since stress singularity was found at the interface end in current specimen of pullout test, interface shear strength (IFSS) obtained from the tests loses its rationality [2]. But a useful conclusion [2] is that when the wedge angle of the matrix is less than a critical angle, the singularity of stress field at the interface end of the specimen in micro-debond test nearly disappears. Following this conclusion, a conic specimen shown in Fig. 1 is presented, in which the wedge angle of the specimen is designed to be less than a critical angle in order to prevent the singular stress field occurred at the interface end. The conic specimen is designed for pullout test to avoid disadvantages inherent in the micro-debond test [3]. An axisymmetric model of fiber/matrix system with arbitrary wedge angles at the interface end is used for the determination of critical wedge angle. With the aid of asymptotic analysis and variable separation, eigenvalue, λ, could be determined by a characteristic determinant. For a given fiber-matrix system, a curve representing the relationship between the stress singularity index and wedge angle could be obtained by solving the characteristic determinant. We define the critical wedge angle, θcr, as the corresponding singularity index of – 0.005. The design of a conic pullout specimen is also discussed. FEM analysis is adopted to calculate the distribution of interfacial stresses near the interface end with different wedge angle. The results verify the rationality of the principle of the design of conic pullout specimen for IFSS measurement.

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Lei, Jin. "The Research on the Interface Performance of Deck of Cement Concrete Bridge and Asphalt Pavement." Advanced Materials Research 723 (August 2013): 237–44. http://dx.doi.org/10.4028/www.scientific.net/amr.723.237.

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The deck of cement concrete bridge and the interface of asphalt pavement, and these two combined items have a direct effect on the useful life of asphalt pavement. According to the indoor shear test and pullout test, we could learn that the interlayer shear strength and the bond strength are strongly affected by temperature, and it is decreased with increasing test temperature. The pullout test analyses the variation regularity of bond strength between four adhesive layers and bridge panel at different temperatures, which proves that the bond strength is also decreased with increasing test temperature. The research suggests that the shear test and pullout test is worthy of evaluating the interface performance between deck and asphalt pavement under the high stability and low temperature conditions.

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Kwon, Minho, Jinsup Kim, Hyunsu Seo, and Wooyoung Jung. "Long-term performance of mechanically post-installed anchor systems." Advances in Structural Engineering 20, no. 3 (July 28, 2016): 288–98. http://dx.doi.org/10.1177/1369433216649396.

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A mechanically post-installed anchor, which is one of the most widely used post-installed anchors in South Korea, was selected to evaluate long-term usage through a pullout test. Two types of specimens were constructed: the original specimens and freeze and thaw specimens. Mechanically post-installed anchors were installed in both of them. A freeze and thaw test method was utilized to consider the long-term usage. The compressive strength of concrete during the freeze and thaw test method is reduced by about 20% compared to that of the original concrete. From the pullout test results, the pullout strength of the freeze and thaw specimen was smaller by about 50% than that of the original specimens. Furthermore, the failure mode of the freeze and thaw specimens was changed. Cone shape destruction of anchors and anchor pullout destruction occurred in the original specimens; concrete pullout destruction occurred dominantly in the freeze and thaw specimens. Based on the comparison results, the reduction factor ( λ) for long-term usage of the mechanically post-installed anchor was derived using a probability function and was proposed to modify the concrete capacity design equation.

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Ko, Hune-Bum. "Evaluation for High Strength Concrete using Pullout Test." Journal of the Korean Institute of Building Construction 8, no. 3 (June 25, 2008): 85–91. http://dx.doi.org/10.5345/jkic.2008.8.3.085.

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Perkins, S. W., and M. Q. Edens. "Finite element modeling of a geosynthetic pullout test." Geotechnical and Geological Engineering 21, no. 4 (2003): 357–75. http://dx.doi.org/10.1023/b:gege.0000006053.77489.c5.

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Dietl, Rupert H. J., Matthias Krammer, Annette Kettler, Hans-Joachim Wilke, Lutz Claes, and Christianto B. Lumenta. "Pullout Test With Three Lumbar Interbody Fusion Cages." Spine 27, no. 10 (May 2002): 1029–35. http://dx.doi.org/10.1097/00007632-200205150-00005.

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Mayo, Richard E., Nathan B. Glondys, and Daniel P. Mayo. "100-Ton (890 kN) Rock Anchor Pullout Test." Practice Periodical on Structural Design and Construction 8, no. 1 (February 2003): 31–35. http://dx.doi.org/10.1061/(asce)1084-0680(2003)8:1(31).

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Collins, F. G., and H. Roper. "Evaluation of concrete spall repairs by pullout test." Materials and Structures 22, no. 4 (July 1989): 280–86. http://dx.doi.org/10.1007/bf02472560.

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Wang, Yan Li, Zhan Lin Cheng, Wei Zhang, Yong Zhen Zuo, Zhen Lin Yu, and Yong Wang. "Pullout Test Research on Interfacial Interaction of Reinforced Band and Gravelly Soil." Applied Mechanics and Materials 580-583 (July 2014): 684–88. http://dx.doi.org/10.4028/www.scientific.net/amm.580-583.684.

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Taking steel-plastic composite reinforced band (CAT) and gravelly soil as the test materials, the pullout tests of reinforced band in gravelly soil with different water contents have been carried out by the laminated shear test instrument. The interface friction characteristics between reinforced band and gravelly soil are studied, and the influences of water content on the interaction characteristics are also discussed. Results show that (1) the extraction of reinforced band is a gradual process. The anchor end began to move firstly because of the extensibility of reinforced belt itself. As interface friction gradually transfer backward by, the free end start to move onward, then displacement schedule curves of the anchor end and the free end are gradually parallel, the whole movement of reinforced belt happens immediately. (2) Pulling force and displacement curve of the pullout friction test displays obviously nonlinear characteristics. Pulling force of the reinforced band increases greatly with increasing displacement at the beginning of the test, then decrease with the increasing displacement after the peak value is reached, the force-displacement curves generally exhibit strain soften characteristics. But it present strain hardening trend under greater normal stress, and pullout frictional strength increases with the increasing normal stress. (3) The pullout friction coefficient of the interface is sensitive to water content. It decreases linearly with the increasing water content.

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Kanakubo, Toshiyuki, Saki Echizen, Jin Wang, and Yu Mu. "Pullout Behavior of Bundled Aramid Fiber in Fiber-Reinforced Cementitious Composite." Materials 13, no. 7 (April 9, 2020): 1746. http://dx.doi.org/10.3390/ma13071746.

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The tensile performance of fiber-reinforced cementitious composite (FRCC) after first matrix cracking is characterized by a tensile stress–crack width relationship called the bridging law. The bridging law can be obtained by an integral calculus of forces carried by individual bridging fibers considering the effect of the fiber inclination angle. The main objective of this study is to investigate experimentally and evaluate the pullout behavior of a single aramid fiber, which is made with a bundling of original yarns of aramid fiber. The bundled aramid fiber has a nonsmooth surface, and it is expected to have good bond performance with the matrix. The test variables in the pullout test are the thickness of the matrix and the inclined angle of the fiber. From the test results, the pullout load–slip curves showed that the load increases lineally until maximum load, after which it decreases gradually. The maximum pullout load and slip at the maximum load increase as the embedded length of the fiber becomes larger. The pullout load–crack width relationship is modeled by a bilinear model, and the bridging law is calculated. The calculated result shows good agreement with the experimental curves obtained by the uniaxial tension test of aramid–FRCC.

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Mourshed, Bilal, Fuad Abdo Al-Sabri, Nashwan Ahmed Qaed, Nader Alaizari, Hashem Motahir Al-Shamiri, and Amal Alfaqih. "Effect of clasp type and pullout location on clasp retention in different environment: In vitro study." European Journal of Dentistry 11, no. 02 (April 2017): 216–20. http://dx.doi.org/10.4103/ejd.ejd_70_17.

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ABSTRACT Objective: The purpose of this study was to investigate the importance of pullout location and clasp types in two different environments to dislodge the clasp. Materials and Methods: Mandibular test models with natural premolars and molar teeth were used to test four types of clasp (each 12) (Akers, Rest plate Akers, Half and Half, and Ring clasp) with three different pullout location for each type (ring on the rest, loop on the saddle, and wax arising from both rests) in dry and natural fresh saliva environment. Each clasp was pulled out 10 times with a crosshead speed of 10 mm/min, and the force required to withdraw each was measured. Statistical Analysis Used: A one-way ANOVA and Tukey test were used. Results: The ring on the saddle pullout location has the highest retention force while ring on the rest was the lowest. In addition, ring clasp has the highest retention force. Conclusion: Clasp type and pullout location had a significant effect on the retentive force.

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Lawson, William D., Priyantha W. Jayawickrama, Timothy A. Wood, and James G. Surles. "Pullout Resistance Factors for Inextensible Mechanically Stabilized Earth Reinforcements in Sandy Backfill." Transportation Research Record: Journal of the Transportation Research Board 2363, no. 1 (January 2013): 21–29. http://dx.doi.org/10.3141/2363-03.

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This paper presents results from a laboratory program of 402 pullout tests of inextensible reinforcements used for walls of mechanically stabilized earth (MSE). Results focus on the evaluation of pullout resistance factors for ribbed-steel strip and welded-steel grid reinforcements embedded in sandy backfill that marginally met AASHTO requirements for select granular fill. This project used Texas Tech University's large-scale MSE test box with dimensions of 12 3 12 3 4 ft and an applied overburden capacity of 40 ft of backfill. This test box facilitated pullout testing at a scale not unlike typical field construction. The research design evaluated pullout resistance factors for both ribbed-strip and welded-grid reinforcements for a variety of independent variables, including overburden pressure, reinforcement length, level of compaction, grid wire size, and grid geometry, such as transverse and longitudinal wire spacing. Appropriate statistical analyses were used to interpret the data within the context of published AASHTO design guidance for inextensible MSE reinforcements. The results show that pullout behaviors of both ribbed strips and welded grids in properly compacted sandy backfill are conservative compared with the default pullout resistance factors provided by AASHTO. The data also suggest that the current AASHTO equations for pullout resistance factors for grid reinforcement do not accurately capture the influence of transverse and longitudinal bar spacings.

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Oliscovicz, Nathalia Ferraz, Antônio Carlos Shimano, Élcio Marcantonio Junior, César Penazzo Lepri, and Andréa Candido dos Reis. "Analysis of Primary Stability of Dental Implants Inserted in Different Substrates Using the Pullout Test and Insertion Torque." International Journal of Dentistry 2013 (2013): 1–5. http://dx.doi.org/10.1155/2013/194987.

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The aim of the study was to evaluate mechanical behavior of implants inserted in three substrates, by measuring the pullout strength and the relative stiffness. 32 implants (Master Porous-Conexao, cylindrical, external hexagon, and surface treatment) were divided into 4 groups (n=8): pig rib bone, polyurethane Synbone, polyurethane Nacional 40 PCF, and pinus wood. Implants were installed with the exact distance of 5 mm of another implant. The insertion torque (N·cm) was quantified using the digital Kratos torque meter and the pullout test (N) was performed by an axial traction force toward the long axis of the implant (2 min/mm) through mount implant devices attached to a piece adapted to a load cell of 200 Kg of a universal testing machine (Emic DL10000). Data of insertion torque and maximum pullout force were submitted to one-way ANOVA and Bonferroni tests (α=0.05). Polyurethane Nacional 40 PCF and pinus wood showed the highest values of insertion torque and pullout force, with significant statistical difference (P<0.05) with other groups. The analysis showed stiffness materials with the highest values for primary stability.

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Suzuki, Takayuki, Masahiro Sato, and Mototsugu Sakai. "Fiber pullout processes and mechanisms of a carbon fiber reinforced silicon nitride ceramic composite." Journal of Materials Research 7, no. 10 (October 1992): 2869–75. http://dx.doi.org/10.1557/jmr.1992.2869.

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Details of fiber pullout processes and mechanisms are addressed for a carbon fiber reinforced silicon nitride ceramic composite. The energy for fiber pullout, γpo, is experimentally measured by the work-of-fracture technique using test specimens with a circumferential notch. A precise determination of the distribution of pullout fibers combined with the experimental results of the pullout energy provides an important insight into the micromechanical processes and mechanisms of the composite fracture. Various energy dissipation processes associated with the composite fracture, the frictional interface shear stress, the Weibull modulus of the reinforcing fibers, and composite designs for improved toughening are discussed.

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Wu, Di, and Chao Xu. "The Influence of Geometric Structure of Geogrids on the Pullout Resistance." Advanced Materials Research 261-263 (May 2011): 586–90. http://dx.doi.org/10.4028/www.scientific.net/amr.261-263.586.

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The influence of geometric characteristic of geogrid on pullout behavior is still an unresolved problem in the application of geosynthetic reinforced soils. The laboratory pullout tests were employed to investigate the effects of geometric structure features on the pull-out test results. The results of this study indicate that the effect of geometric structure on pullout behavior is reflected in two aspects: geogrid type and mesh form of geogrid. The variation of geogrid types can lead to the changes of the pullout force and pullout modulus. For the latter one, the reduction of longitudinal and transverse geogrid ribs not only causes the decrease of friction and transverse rib bearing resistance, but also changes the mesh form which is the geometric structure of grids.

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Ortiz Merino, J. L., A. Cock, Steve G. Roberts, and Richard I. Todd. "Quantitative Surface Fractography of Alumina and Alumina-SiC Composites during Diamond Grinding." Key Engineering Materials 290 (July 2005): 149–59. http://dx.doi.org/10.4028/www.scientific.net/kem.290.149.

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It has recently been shown that small additions of SiC to alumina can significantly improve both the surface finish for a given grinding treatment, and the resistance to severe wear. This paper describes experiments designed to obtain a clearer understanding of the mechanisms involved by correlating quantitative measurements of surface fracture during a standard abrasive wear test with the wear rate for a range of microstructures. The surface fracture parameters measured were (i) the proportion of the surface in which pieces of material had been removed by brittle fracture, and (ii) the size (equivalent circular diameter and depth) of the individual pullouts. Microstructures with systematic variations in grain size, SiC volume fraction, SiC particle size, SiC position (inter- or intra-granular) and sintering aids were tested. The results indicate that the reduction in wear rate on adding SiC or reducing the grain size is caused by a reduction in the area fraction of surface pullout by brittle fracture. For low SiC contents (~2vol%), this reduction in surface pullout is a consequence of the reduction in size of the individual pullouts. For higher SiC contents (10vol%), there is evidence that the nucleation of surface cracking is also inhibited. The underlying micromechanisms responsible for these effects are discussed.

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Zhou, Wan-Huan, Jian-Hua Yin, and Cheng-Yu Hong. "Finite element modelling of pullout testing on a soil nail in a pullout box under different overburden and grouting pressures." Canadian Geotechnical Journal 48, no. 4 (April 2011): 557–67. http://dx.doi.org/10.1139/t10-086.

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In this paper, a three-dimensional (3D) finite element (FE) model is developed to simulate the pullout behaviour of a soil nail in a soil-nail pullout box under different overburden and grouting pressures. The FE model simulates all the procedures of a pullout test on a grouted soil nail in a compacted and saturated completely decomposed granite (CDG) soil. The stress–strain behaviour of the CDG soil is described by a modified Drucker–Prager/Cap model, while that of the soil–nail interface is represented by the Coulomb friction model. Triaxial experiment data are used to calibrate the soil parameters in the soil constitutive model. The interface parameters are determined from back-analysis with the laboratory soil-nail pullout data. The soil stress variations surrounding the soil nail during drilling, grouting, saturation, and pullout are all well simulated by the FE modelling and compared with available test data. The comparisons between the modelling and experimental data have shown that the established FE can well simulate the pullout behaviour of a soil nail in a soil mass. Based on this, the verified FE model has the potential to simulate the performance of a soil nail in a field soil slope.

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Carmouche, Jonathan J., Robert W. Molinari, Tad Gerlinger, John Devine, and Troy Patience. "Effects of pilot hole preparation technique on pedicle screw fixation in different regions of the osteoporotic thoracic and lumbar spine." Journal of Neurosurgery: Spine 3, no. 5 (November 2005): 364–70. http://dx.doi.org/10.3171/spi.2005.3.5.0364.

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Object. The authors evaluated the effects of pilot hole preparation technique on insertional torque and axial pullout resistance in osteoporotic thoracic and lumbar vertebrae. Methods. Using a probe technique and fluoroscopy, 102 pedicle screws were placed in 51 dual-energy x-ray absorptiometry—proven osteoporotic thoracic and lumbar levels. Screws were inserted using the same-size tapping, one-size-under tapping, or no-tapping technique. Insertional torque and axial pullout resistance were measured. Analysis of variance, Fisher exact test, and regression analysis were performed. Same-size tapping decreased pullout resistance in the lumbar spine. There was no effect on pullout resistance in the thoracic spine. Pullout resistance values were lower for all insertion techniques in the upper thoracic spine. Insertional torque and bone mineral density correlated with pullout resistance in the thoracic and lumbar spine. Conclusions. Tapping decreased pedicle screw pullout resistance in the osteoporotic human lumbar spine, although it did not affect pullout strength in the thoracic spine. Tapping decreased insertional torque in upper thoracic levels. Surgeons should optimize overall construct rigidity when placing thoracic pedicle screws in patients with spinal segment osteoporosis.

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Prasad, Y. V. S. N., and S. Narasimha Rao. "Pullout behaviour of model pile and helical pile anchors Subjected to lateral cyclic loading." Canadian Geotechnical Journal 31, no. 1 (February 1, 1994): 110–19. http://dx.doi.org/10.1139/t94-012.

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This paper presents the effect of lateral cyclic loading on the pullout capacity of model and helical piles in clayey soil. The tests were conducted on short rigid model piles in the laboratory in three phases, namely lateral static load tests, lateral cyclic load tests, and vertical pullout tests. From the test results it was found that the lateral cyclic loading affects the pullout capacity of piles substantially. Reduction in pullout capacity mainly depends upon the lateral deflection of the pile during cyclic loading and the embedment ratio of the pile. This reduction in the pullout capacity of model piles is presented in terms of nondimensional parameters, viz., degradation factor, lateral deflection ratio, and embedment ratio of pile. However, in the case of helical piles under similar conditions, it was found that the lateral cyclic loading has very little influence on the pullout capacity. The reasons for the better performance of helical piles over ordinary piles are explained. Key words : clay, degradation factor, helical pile, lateral cyclic loading, lateral deflection, Joading level, pile, pullout capacity.

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Gurung, N., and Y. Iwao. "Numerical simulation of pullout response for planar soil reinforcements." Canadian Geotechnical Journal 36, no. 3 (October 25, 1999): 455–66. http://dx.doi.org/10.1139/t99-006.

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This paper presents a series of numerical simulations for laboratory and field pullout tests. A nonlinear differential expression for interface pullout from simple equilibrium of forces and hyperbolic interface model for shear displacement variation along the length of the planar reinforcement is utilised. Finite difference numerical method and nondimensional expressions are adopted for wider application. The relative stiffness and relative displacement parameters are defined and related to the interface pullout interaction mechanism. A parametric study to develop computer-simulated interface design charts for a practical range of relative stiffness and relative bond resistance is theoretically illustrated. The pullout model is capable of simulating the responses of inextensible as well as highly extensible planar reinforcements. The model responses compared satisfactorily with the available theoretical and experimental pullout test results for steel straps, polymer strips, geotextiles, geomembranes, nylon geosynthetics, and geogrid reinforcements.Key words: geosynthetics, extensible reinforcement, numerical simulation, parametric study, pullout testing, reinforced soil.

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Das, Braja M., and Miguel Picorness. "ULTIMATE RESISTANCE OF VERTICAL PLATE ANCHORS IN CLAY." Coastal Engineering Proceedings 1, no. 20 (January 29, 1986): 134. http://dx.doi.org/10.9753/icce.v20.134.

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Laboratory model test results for the ultimate pullout resistance of vertical square anchors embedded in saturated or near saturated clay have been presented. The undrained shear strength of the clay and the embedment ratio of the anchors have been varied. Based on the model test results, an empirical parametric relationship for estimation of the ultimate pullout resistance of shallow and deep square anchors has been presented.

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Lee, Seok-Won, Tea-Seob Kim, Bo-Kyoung Sim, Jong-Sun Kim, and In-Mo Lee. "Effect of pressurized grouting on pullout resistance and group efficiency of compression ground anchor." Canadian Geotechnical Journal 49, no. 8 (August 2012): 939–53. http://dx.doi.org/10.1139/t2012-059.

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The purpose of this study is to investigate the effect of pressurized grouting on pullout resistance and the group effect of the compression ground anchor by performing pilot-scale laboratory chamber tests and field tests. The laboratory test results show that the enlargement of the anchor body diameter estimated theoretically by combining the cavity expansion theory and grout penetration characteristics matches reasonably well with that obtained from experiments. The required injection time as a function of the coefficient of permeability of the ground is proposed. The results of a series of field anchor pullout tests show that the effect of pressurized grouting is more prominent in a softer ground with a smaller SPT-N value for an increase in both anchor body diameter and pullout resistance. The pressurized grouting effect in comparison with gravitational grouting was found to be almost zero if the SPT-N value is more than 50. Based on experimental results, a new equation to estimate the pullout resistance as a function of the SPT-N60 value is proposed. In addition, based on in situ group anchor pullout test results, a new group effect equation is proposed.

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Choi, Dong-Uk, Sang-Su Ha, and Chang-Ho Lee. "Development Length of GFRP Rebars Based on Pullout Test." Journal of the Korea Concrete Institute 19, no. 3 (June 30, 2007): 323–31. http://dx.doi.org/10.4334/jkci.2007.19.3.323.

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Tagaya, Kozo, Ronald F. Scott, and Hisao Aboshi. "Scale Effect in Anchor Pullout Test by Centrifugal Technique." Soils and Foundations 28, no. 3 (September 1988): 1–12. http://dx.doi.org/10.3208/sandf1972.28.3_1.

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Sugimoto, M., and A. M. N. Alagiyawanna. "Pullout Behavior of Geogrid by Test and Numerical Analysis." Journal of Geotechnical and Geoenvironmental Engineering 129, no. 4 (April 2003): 361–71. http://dx.doi.org/10.1061/(asce)1090-0241(2003)129:4(361).

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Pouranvari, M. "On the Failure Mode of Resistance Spot Welded Hsla 420 Steel / Tryb Uszkodzenia Zgrzewanych Spoin Stali Hsla 420." Archives of Metallurgy and Materials 58, no. 1 (March 1, 2013): 67–72. http://dx.doi.org/10.2478/v10172-012-0152-y.

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Failure mode of resistance spot welds (interfacial vs. pullout) is a qualitative measure of resistance spot weld performance. Considering adverse effect of interfacial failure mode on the vehicle crashworthiness, process parameters should be adjusted so that the pullout failure mode is guaranteed ensuring reliability of spot welds during vehicle lifetime. In this paper, metallurgical and mechanical properties of HSLA 420 resistance spot welds are studied with particular attention to the failure mode. Results showed that the conventional weld size recommendation of 4t0:5 (t is sheet thickness) is not sufficient to guarantee pullout failure mode for HSLA steel spot welds during the tensile-shear test. Considering the failure mechanism of spot welds during the tensileshear test, minimum required fusion zone size to ensure the pullout failure mode was estimated using an analytical model. Fusion zone size proved to be the most important controlling factor for peak load and energy absorption of HSLA 420 resistance spot weld.

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Fu, Jianjun, Junfeng Li, Cheng Chen, and Rui Rui. "DEM-FDM Coupled Numerical Study on the Reinforcement of Biaxial and Triaxial Geogrid Using Pullout Test." Applied Sciences 11, no. 19 (September 27, 2021): 9001. http://dx.doi.org/10.3390/app11199001.

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The key to modeling the interlocking of geogrid-reinforced ballast is considering both the continuous deformation characteristics of the geogrid and the discontinuity of the ballast particles. For this purpose, pullout tests using biaxial and triaxial geogrids were simulated using the coupled discrete element method (DEM) and finite difference method (FDM). In this coupled model, two real-shaped geogrid models with square and triangular apertures were established using the solid element in FLAC3D. Meanwhile, simplified shaped clumps were used to represent the ballast using PFC3D. The calibration test simulation showed that the accurately formed geogrid model can reproduce the deformation and strength characteristics of a geogrid. The pullout simulation results show that the DEM-FDM method can well predict the relationship between pullout force and displacement, which is more accurate than the DEM method. For ballast particles of 40 mm in size, both the experiment and simulation results showed that the triaxial geogrid of 75 mm is better than the 65-mm biaxial geogrid. In addition, the DEM-FDM method can study the interaction mechanism between the particles and the geogrid from a microscopic view, and also reveal the similar deformation behavior of the geogrid in the pullout process. Therefore, the DEM-FDM coupled method can not only investigate the interlocking mechanism between the ballast and particles but can also provide a great method for evaluating the performance of different types of geogrids.

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Fuerderer, Sebastian, Jan Vonhoegen, Oliver Coenen, Joern Michael, Juergen Koebke, and Peer Eysel. "In vitro comparison of the pullout strength of 3 anterior double-screw fixation techniques with different screw angulations." Journal of Neurosurgery: Spine 14, no. 3 (March 2011): 367–71. http://dx.doi.org/10.3171/2010.9.spine09495.

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Object The pullout resistance of double-screw fixation systems in anterior spine surgery has been shown to be dependent on screw length as well as on screw angulation. The objective of the study was to evaluate the pullout strength of anterior double-screw systems with different angulations. Methods The authors conducted a comparative pullout test of converging, parallel, and diverging angulations of double-screw systems in human cadavers. Twenty-four human vertebral bodies from T-11 to L-1 were harvested from 8 donors, dissected from surrounding tissue, and matched to 3 different fixation groups. Three systems were tested: VentroFix, with near parallel screw direction; the Hopf Anterior Fixation System (HAFS), with converging screw angulation; and the ART anterior system, with diverging screw angulation. Results The mean (± SD) pullout strength of the VentroFix system was 699 ± 214 N, whereas the HAFS resisted to 591 ± 372 N. The ART anterior system with diverging screws demonstrated a pullout resistance of 810 ± 273 N. There was no significant difference amongst the pullout forces of the 3 groups (p > 0.05). In the HAFS and the ART anterior group, a weak correlation of pullout strength and bone mineral density measured by quantitative CT was found (r = 0.59 and r = 0.62, respectively), whereas the pullout force of the VentroFix system was not correlated with bone mineral density (r = 0.33). Conclusions The in vitro pullout resistance of anterior double-screw systems does not appear to depend on screw angulation.

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Wu, Jason Y., and Jr Min Chang. "Effect of Wetting on the Pullout Resistance of Grouted Soil Nails." Applied Mechanics and Materials 226-228 (November 2012): 1304–7. http://dx.doi.org/10.4028/www.scientific.net/amm.226-228.1304.

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In this research, laboratory pullout tests were conducted on grouted soil nails to study the effect of wetting on the interface shear resistance between nail and soil during pullout. Deformed bars with equal size to the true soil nails were used as model nails. The soil used was silty fine sand collected at the site and prepared to a very dense condition. Rainfall infiltration was simulated using duplicated soil nails inundated by water for different periods. Test results indicated that the peak pullout resistance strongly decreases upon wetting, with a reduction of about 60% after soaking for 28 days. However, the experiments showed that there is a threshold water content (or soaking time) beyond which the effect of infiltration on the pullout resistance is reduced. The laboratory protocols developed in this study offered an easy scheme for the prediction of the pullout capacity of a grouted soil nail upon wetting.

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Brinley, Christine L., Rolf Behrents, Ki Beom Kim, Sridhar Condoor, Hee-Moon Kyung, and Peter H. Buschang. "Pitch and Longitudinal Fluting Effects on the Primary Stability of Miniscrew Implants." Angle Orthodontist 79, no. 6 (November 1, 2009): 1156–61. http://dx.doi.org/10.2319/103108-554r.1.

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Abstract Objective: To test the hypotheses that pitch and fluting have no effect on the primary stability of miniscrew implants (MSIs). Materials and Methods: Maximum placement torque and pullout strength of experimental MSIs were compared with those of control MSIs with the use of synthetic and cadaver bone. MSIs with 1.00 mm pitch were compared with those with 1.25 mm and 0.75 mm pitch; MSIs with three longitudinal flutes were compared with the same MSIs without flutes. A total of 60 MSIs (15 of each design) were evaluated with synthetic bone; a split-mouth cadaver model was used to compare the three experimental designs against the 1 mm control MSIs (total of 90 MSIs). Results: The synthetic bone model showed higher placement torque and pullout strength for the 0.75 pitch than for the 1.0 mm and 1.25 mm pitch MSIs, but differences were significant (P < .05) only for pullout strength. The cadaver model showed no significant differences in placement torque or pullout strength associated with pitch. Both synthetic and cadaver bone models showed that MSIs with flutes had significantly (P < .05) higher placement torque and pullout strength. Spearman correlations between placement torque and pullout strength were statistically significant for both synthetic (r = .504) and cadaver (r = .502) bone. Conclusion: Within limits, decreasing MSI pitch increases pullout strength, and fluting increases both placement torque and pullout strength.

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Journal articles on the topic 'Pullout test'

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