The Experts below are selected from a list of 9912 Experts worldwide ranked by ideXlab platform
Antonín Lokaj - One of the best experts on this subject based on the ideXlab platform.
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Round Timber Bolted Joints Reinforcement Methods
Advanced Materials Research, 2014Co-Authors: Kristýna Klajmonová, Antonín LokajAbstract:This paper presents the results of static tests of non-reinforced and reinforced round timber Bolted Joints with slotted-in steel plates. In this article, a new approach to the reinforcement of round timber Bolted Joints is presented. Based on results from tension tests of timber Bolted joint samples, reinforcement methods were proposed. From these, modified washers and boost with screws were chosen for further tension testing. Results were compared to unreinforced ones and rate of improvement established.
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round timber Bolted Joints with mechanical reinforcement
Advanced Materials Research, 2013Co-Authors: Kristýna Klajmonová, Antonín LokajAbstract:This paper presents the results of static tests of round timber Bolted Joints with inserted steel plates. All round timber Joints static tests in tension were carried out on pressure machine EU 100 in laboratory of the Faculty of Civil Engineering VSB-TU Ostrava. At first, timber specimens were tested without reinforcement. Based on these results, mechanical reinforcement methods were proposed: using modified washers and boost with screws. These samples were also tested. Rate of improvement in tensile strength was established for used reinforcement method.
Kristýna Klajmonová - One of the best experts on this subject based on the ideXlab platform.
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Round Timber Bolted Joints Reinforcement Methods
Advanced Materials Research, 2014Co-Authors: Kristýna Klajmonová, Antonín LokajAbstract:This paper presents the results of static tests of non-reinforced and reinforced round timber Bolted Joints with slotted-in steel plates. In this article, a new approach to the reinforcement of round timber Bolted Joints is presented. Based on results from tension tests of timber Bolted joint samples, reinforcement methods were proposed. From these, modified washers and boost with screws were chosen for further tension testing. Results were compared to unreinforced ones and rate of improvement established.
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round timber Bolted Joints with mechanical reinforcement
Advanced Materials Research, 2013Co-Authors: Kristýna Klajmonová, Antonín LokajAbstract:This paper presents the results of static tests of round timber Bolted Joints with inserted steel plates. All round timber Joints static tests in tension were carried out on pressure machine EU 100 in laboratory of the Faculty of Civil Engineering VSB-TU Ostrava. At first, timber specimens were tested without reinforcement. Based on these results, mechanical reinforcement methods were proposed: using modified washers and boost with screws. These samples were also tested. Rate of improvement in tensile strength was established for used reinforcement method.
Yusuke Fukuba - One of the best experts on this subject based on the ideXlab platform.
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mechanical behavior of rotational screw thread loosening in Bolted Joints under repeated temperature changes
Volume 2: Computer Applications Technology and Bolted Joints, 2008Co-Authors: Toshiyuki Sawa, Yasumasa Shoji, Mitsutoshi Ishimura, Yusuke FukubaAbstract:Bolted Joints have been used in mechanical structures. However, loosening accidents sometimes happen under several types of loadings. Recently, some studies have been conducted on the screw thread loosening in Bolted Joints. It is verified that Bolted Joints are loosened when transverse repeated loadings are applied. A lot of parts for preventing the loosening in the Joints have been proposed. Among these parts, eccentric nut is especially expected to be the solution for preventing the loosening. Some studies on no rotational loosening in Bolted Joints under thermal changes have also conducted. However, few studies on rotational screw thread loosening in Bolted Joints have conducted. In our previous study, mechanism of rotational screw thread loosening in Bolted joint under repeated temperature changes was examined. However, the difference in the loosening mechanism between the FEM results and the experimental results was substantial. In this study, the effect of the incline at the bearing surfaces was taken into consideration on the loosening. In addition, the loosening in the Bolted joint with the eccentric nut under repeated temperature changes was examined using finite element method (FEM) calculations. Discussion is made on the mechanism and a solution of rotational screw thread loosening in the Bolted Joints under the repeated temperature changes. The results show that a reduction in axial bolt force was increased when the incline at the bearing surfaces was taken into consideration and the eccentric nut was shown for preventing the bolt loosening.Copyright © 2008 by ASME
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mechanism of rotational screw thread loosening in Bolted Joints under repeated temperature changes
Volume 2: Computer Applications Technology and Bolted Joints, 2007Co-Authors: Toshiyuki Sawa, Hiroshi Yamanaka, Mitsutoshi Ishimura, Yusuke FukubaAbstract:Bolted Joints have been used in mechanical structures. However, loosening accidents sometimes happen under several types of loadings. Recently, some studies have been conducted on the screw thread loosening in Bolted Joints. It is verified that Bolted Joints are loosened when transverse repeated loadings are applied. Some studies on no rotational loosening in Bolted Joints under thermal changes have also conducted. However, few studies on rotational screw thread loosening in Bolted Joints have conducted. In this study, rotational screw thread loosening in Bolted joint under repeated temperature changes is examined. Effects of the linear thermal expansion coefficient of clamped parts and number of repeated temperature changes are examined by the measurements and finite element analyses. In the experiments, a Bolted joint, which consist of two rectangular plates fastened at room temperature by two bolts and nuts, are put in a furnace and heated by an electric heater. Then, the Bolted joint is cooled at room temperature. These thermal cycles are repeated. Bolt temperature and bolt load were measured. Loosening is evaluated from the reductions in the bolt load. Finite element analyses were carried out for clarifying the loosening mechanism. Discussion is made on the mechanism of rotational screw thread loosening in Bolted Joints under repeated temperature changes. The results show that loosening occurs under repeated temperature changes due to difference in the linear thermal expansion coefficients of the different clamped parts.Copyright © 2007 by ASME
Toshiyuki Sawa - One of the best experts on this subject based on the ideXlab platform.
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A Loosening Mechanism of Bolted Joints Under Repeated Transverse Displacements
Volume 2: Computer Technology and Bolted Joints, 2012Co-Authors: Toshiyuki Sawa, Mitsutoshi Ishimura, Takanori NagaoAbstract:Loosening accidents sometimes occur under several types of loadings such as winds, vibrations, earthquakes, impact loads and thermal changes. Recently, some studies have been conducted on the screw thread loosening in Bolted Joints under repeated transverse displacements. It is well known that Bolted Joints are easily loosened when repeated transverse loadings are applied [1]. In assembling Bolted Joints, double nut, spring plate washers and hexagon nuts with flange have been used. However, a few studies have been carried out on the loosening mechanism in Bolted Joints with the above parts for preventing the loosening. In the present paper, the effects of the double nut, spring plate washers and hexagon nuts with flange mentioned above are examined using FEM calculations. The experiments to measure the loosening in Bolted Joints were carried out using Junker’s testing machine for validation of the FEM calculations. As the results, it is seen that the loosening speed is the maximum when the hexagon nuts with flange is used. In addition, it is also observed that Bolted Joints in which almost nut parts for preventing loosening are applied are loosened easily in the FEM calculations. The amounts of loosening for Bolted Joints with double nut, spring plate washers and hexagon nuts with flange are in a fairly good agreement with the measured results. Discussion is made on the loosening mechanism of Bolted Joints with the above parts under repeated transverse displacements.Copyright © 2012 by ASME
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mechanical behavior of rotational screw thread loosening in Bolted Joints under repeated temperature changes
Volume 2: Computer Applications Technology and Bolted Joints, 2008Co-Authors: Toshiyuki Sawa, Yasumasa Shoji, Mitsutoshi Ishimura, Yusuke FukubaAbstract:Bolted Joints have been used in mechanical structures. However, loosening accidents sometimes happen under several types of loadings. Recently, some studies have been conducted on the screw thread loosening in Bolted Joints. It is verified that Bolted Joints are loosened when transverse repeated loadings are applied. A lot of parts for preventing the loosening in the Joints have been proposed. Among these parts, eccentric nut is especially expected to be the solution for preventing the loosening. Some studies on no rotational loosening in Bolted Joints under thermal changes have also conducted. However, few studies on rotational screw thread loosening in Bolted Joints have conducted. In our previous study, mechanism of rotational screw thread loosening in Bolted joint under repeated temperature changes was examined. However, the difference in the loosening mechanism between the FEM results and the experimental results was substantial. In this study, the effect of the incline at the bearing surfaces was taken into consideration on the loosening. In addition, the loosening in the Bolted joint with the eccentric nut under repeated temperature changes was examined using finite element method (FEM) calculations. Discussion is made on the mechanism and a solution of rotational screw thread loosening in the Bolted Joints under the repeated temperature changes. The results show that a reduction in axial bolt force was increased when the incline at the bearing surfaces was taken into consideration and the eccentric nut was shown for preventing the bolt loosening.Copyright © 2008 by ASME
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mechanism of rotational screw thread loosening in Bolted Joints under repeated temperature changes
Volume 2: Computer Applications Technology and Bolted Joints, 2007Co-Authors: Toshiyuki Sawa, Hiroshi Yamanaka, Mitsutoshi Ishimura, Yusuke FukubaAbstract:Bolted Joints have been used in mechanical structures. However, loosening accidents sometimes happen under several types of loadings. Recently, some studies have been conducted on the screw thread loosening in Bolted Joints. It is verified that Bolted Joints are loosened when transverse repeated loadings are applied. Some studies on no rotational loosening in Bolted Joints under thermal changes have also conducted. However, few studies on rotational screw thread loosening in Bolted Joints have conducted. In this study, rotational screw thread loosening in Bolted joint under repeated temperature changes is examined. Effects of the linear thermal expansion coefficient of clamped parts and number of repeated temperature changes are examined by the measurements and finite element analyses. In the experiments, a Bolted joint, which consist of two rectangular plates fastened at room temperature by two bolts and nuts, are put in a furnace and heated by an electric heater. Then, the Bolted joint is cooled at room temperature. These thermal cycles are repeated. Bolt temperature and bolt load were measured. Loosening is evaluated from the reductions in the bolt load. Finite element analyses were carried out for clarifying the loosening mechanism. Discussion is made on the mechanism of rotational screw thread loosening in Bolted Joints under repeated temperature changes. The results show that loosening occurs under repeated temperature changes due to difference in the linear thermal expansion coefficients of the different clamped parts.Copyright © 2007 by ASME
Anthony M Waas - One of the best experts on this subject based on the ideXlab platform.
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progressive damage and failure analysis of single lap shear and double lap shear Bolted Joints
Composites Part A-applied Science and Manufacturing, 2018Co-Authors: Ashith P K Joseph, Paul Davidson, Anthony M WaasAbstract:Abstract Intra-inter crack band model (I2CBM) is proposed for studying the progressive damage and failure of laminated composite Bolted Joints. The model combines Schapery theory for matrix microcrack modeling with crack band theory for lamina macroscopic failure modeling in a standard 3D finite element framework and is implemented as material laws at element integration points. Three different failure planes defined by material orthotropy are considered for the modeling of macroscopic failure using crack band theory. This procedure allows the model to be used either as an intraply element or as an interply element of finite thickness by an appropriate choice of the crack planes of interest. Localized bearing failure, observed in Bolted Joints, is modeled using a residual strength approach in the post-peak response of individual ply elements. Simulation results for single lap shear and double lap shear Bolted joint problems are compared against experiments for model validation.
