To see the other types of publications on this topic, follow the link: Bolted joints Joints (Engineering).
Journal articles on the topic 'Bolted joints Joints (Engineering)'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Bolted joints Joints (Engineering).'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Qin, ZY, QK Han, and FL Chu. "Analytical model of bolted disk–drum joints and its application to dynamic analysis of jointed rotor." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 228, no. 4 (May 9, 2013): 646–63. http://dx.doi.org/10.1177/0954406213489084.
Full textAbstract:
Bolted joints are widely used in aero-engines. One of the common applications is to connect the rotor disks and drums. An analytical model for the bending stiffness of the bolted disk–drum joints is developed. The joint stiffness calculated using the analytical model shows sound agreement with the calculation obtained based on finite element analyses. The joint stiffness model is then implemented into the dynamic model of a simple rotor connected through the bolted disk–drum joint. Finally, the whirling characteristics and steady-state response of the jointed rotor are investigated to evaluate the influence of the joint on the rotor dynamics, where the harmonic balance method is employed to calculate the steady-state response to unbalance force. The simulation results show that the joint influence on the whirling characteristics of the rotor system can be neglected; whereas, the presence of the bolted disk–drum joint may lead to a decrease in the rotor critical speeds due to the softening of the joint stiffness. The proposed analytical model for the bolted disk–drum joints can be adopted conveniently for different types of rotor systems connected by bolted disk–drum joints.
2
Lin, Hang, Penghui Sun, and Yifan Chen. "Shear Strength of Flat Joint considering Influencing Area of Bolts." Advances in Civil Engineering 2020 (November 12, 2020): 1–12. http://dx.doi.org/10.1155/2020/8878432.
Full textAbstract:
Bolt is popular in the reinforcement of geotechnical engineering, which can significantly improve the strength and stability of jointed rock mass. For bolted joint, the bolting area is a certain scope instead of the entire joint surface; therefore, it is necessary to study the effect of bolt influencing area on the shear strength of rock joints. In this paper, a series of laboratory direct shear tests were executed on the bolted joints to explore the influence of bolts on the joint shear strength, as well as the influencing area of bolt. Via successively changing bolting angle and bolt number, the shear stress-shear displacement curves of bolted joints were recorded and the variation law of shear strength was analyzed. Based on the assumption of the circular influencing area of bolt, the influence coefficient m (defined as the diameter ratio of the influencing area to the bolt) was introduced to establish the theoretical calculation model of the shear strength of bolted joint, which was verified by test results. Furthermore, the value of m was changed, and the shear strengths of bolted joints under different bolting condition were calculated to compare with the test results. The average relative error Eave was selected to determine the optimal value of m under the corresponding bolting condition, and it tends to sufficiently small values under the case of m > 30 for one-bolted joint and m > 25 for two-bolted joint, as well as m > 20 for three-bolted joint, which demonstrates that m can be applied to effectively calculate the actual influencing area of bolt.
3
Omar, R., M. N. Abdul Rani, and M. A. Yunus. "Representation of bolted joints in a structure using finite element modelling and model updating." Journal of Mechanical Engineering and Sciences 14, no. 3 (September 30, 2020): 7141–51. http://dx.doi.org/10.15282/jmes.14.3.2020.15.0560.
Full textAbstract:
Efficient and accurate finite element (FE) modelling of bolted joints is essential for increasing confidence in the investigation of structural vibrations. However, modelling of bolted joints for the investigation is often found to be very challenging. This paper proposes an appropriate FE representation of bolted joints for the prediction of the dynamic behaviour of a bolted joint structure. Two different FE models of the bolted joint structure with two different FE element connectors, which are CBEAM and CBUSH, representing the bolted joints are developed. Modal updating is used to correlate the two FE models with the experimental model. The dynamic behaviour of the two FE models is compared with experimental modal analysis to evaluate and determine the most appropriate FE model of the bolted joint structure. The comparison reveals that the CBUSH element connectors based FE model has a greater capability in representing the bolted joints with 86 percent accuracy and greater efficiency in updating the model parameters. The proposed modelling technique will be useful in the modelling of a complex structure with a large number of bolted joints.
4
Stephen, JT, MB Marshall, and R. Lewis. "Relaxation of contact pressure and self-loosening in dynamic bolted joints." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 231, no. 18 (May 5, 2016): 3462–75. http://dx.doi.org/10.1177/0954406216645130.
Full textAbstract:
Bolted joints are widely used in a variety of engineering applications where they are dynamically loaded with frequencies of vibration spread over a wide spectrum with the same general effects. When under dynamic loading, bolted joints can become loose due to a loss in clamping pressure in the joints. This vibrational loosening sometimes can cause serious problems, and in some cases can lead to fatal consequences if it remains undetected. Non-intrusive ultrasonic and image processing techniques were simultaneously used to investigate the relaxation of contact pressure and loosening of bolted joints subjected to cyclic shear loading. Three critical areas, the contact interface of the bolted component, the bolt length and the rotation of the bolt head, were monitored during loosening of the joints. The results show that loosening of bolted joints can be grouped into three stages: very rapid, rapid, and gradual loosening. The earliest stage of the loosening of bolted joints is characterised by cyclic strain ratcheting–loosening of the bolted joint during vibration without rotation of the bolt head. The higher the rate of relaxation at this early stage, the lower is the resistance of the bolted joint to vibration-induced loosening. Both the dynamic shear load and an additional constant shear load in another direction were observed to affect the rate of loosening, and at this early stage, a rise in the magnitude of the additional constant shear load increases the rate of loosening. Furthermore, the contact pressure distribution affects the rate of loosening at the bolted joint interface, as loosening increases away from area of high contact pressure.
5
Dravid, Shriram, Kartikeya Triphati, and Manoj Chouksey. "Experimental study of loosening behavior of plain shank bolted joint under dynamic loading." International Journal of Structural Integrity 6, no. 1 (February 2, 2015): 26–39. http://dx.doi.org/10.1108/ijsi-09-2013-0024.
Full textAbstract:
Purpose – Bolted joints are commonly used to connect structural members. These joints can be disassembled whenever required. Various types of washers are used between nut and the connected member to keep the joints tight. However, these joints often become loose over time under dynamic loading conditions. The purpose of this paper is to know the reasons of loosening of bolted joints and to identify the main parameters that contribute to the bolt loosening, and to verify them with previous work. Design/methodology/approach – This work studies loosening of bolted joint in a test rig under varying tightening torque as well as for various types of washers used as the number of load cycles increases. Four trial runs are taken for each case considered and the average results are found out to minimize possible sources of errors. For the purpose, a specifically made test rig is used which is capable of applying harmonic load on the bolted joint by the lever action. Findings – The study compares the loosening of bolted joint with and without washer, and also under different initial tightening conditions. This study has shown the suitability of the test rig, methodology and parameters for study of loosening in bolted joints. This study presents an indigenous test, capable of applying harmonic load on bolted joint. Originality/value – The results establish that the methodology and parameters selected were appropriate for the purpose of study of loosening of bolted joints. This study has provided a base line for further work to understand the loosening of bolted joints.
6
Hayman, Edward, and Clyde Neely. "Solving the Puzzle of Bolted Joints." Mechanical Engineering 133, no. 06 (June 1, 2011): 48–52. http://dx.doi.org/10.1115/1.2011-jun-5.
Full textAbstract:
This article discusses the various ways of solving the puzzle of bolted joint assembly. In 2001, The PCC-1-2000 Guidelines for Pressure Boundary Bolted Flange Joint Assembly presented with knowledge and practices specific to the assembly of bolted flange joints. The puzzle solution that came from this box was the most definitive to date and allowed those dealing with bolted joints to assemble the variables by methods that had been used successfully for many years by many people. This document is helping people across industry not only to assemble bolted flange joints, but also to establish joint integrity programs, procedures, and best practices. PCC-1-2010 shifts the emphasis to gasket stress and gasket type and provides instruction and information pertinent to bolt torque values. The 2010 document contains, for instance, a whole section on bolt stress—the unit load that should be put on the bolts—and includes tables as well.
7
Naraghi, Tahereh, and Ali S. Nobari. "A novel method for the identification of a model for the nonlinear characteristic of a bolted lap-joint." Journal of Vibration and Control 23, no. 3 (August 9, 2016): 484–500. http://dx.doi.org/10.1177/1077546315581238.
Full textAbstract:
Joints are the main source of nonlinearity and energy dissipation in large assembled structures which could be otherwise considered as linear. Consequently, modeling and parameter identification of joints play a significant role in any successful design and finite element (FE) modeling of structures. In the present research, an identification procedure is proposed for the modeling of the nonlinear behavior of a bolted joint. The main emphasis are placed on the simplicity of the experimental procedures involved as well as ease of incorporation of the identified model in the FE model of the structure. Using the concept of the optimum equivalent linear frequency response function, structure was excited by two levels of random force, at two bolt preload levels, and then the eigen values of the nonlinear structure and the inverse eigen-sensitivity identification technique are used, in order to identify the nonlinear properties of bolted joints. The results of implementing the method are promising and indicative of the fact that, in contrast to static Iwan’s model of a bolted joint, the equivalent dynamic characteristics of a bolted joint may be frequency dependent, as the different modes will affect the interface zone of the jointed structures in a different manner.
8
Zhai, Xue, Cheng-Wei Fei, Jian-Jun Wang, and Xing-Yu Yao. "Parametric modeling and updating for bolted joints of aeroengine casings." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 230, no. 16 (August 9, 2016): 2940–51. http://dx.doi.org/10.1177/0954406215607900.
Full textAbstract:
To establish accurate finite element (FE) model of bolted joint structures of aeroengine stator system (casings), this work implements the parametric FE modeling and updating of bolted joints of aeroengine stator system with multi-characteristic responses (multi-object). Firstly, the parametric FE modeling approach of bolted joint structure was developed based on the thin layer element method. And then the FE model updating thought of aeroengine stator system was developed based on the probabilistic analysis method. Finally, the parametric modeling and updating of the bolted joints of aeroengine stator system with multi-characteristic responses was completed by the optimization iteration calculation of objective function based on the proposed methods and the static stiffness testing data. Through the parametric modeling of bolted joint structures based on the thin layer method, the complexity of FE model of aeroengine casings with many bolted joint structures is reduced. As shown in the FE model updating of casings with multi-characteristic responses analysis, the static stiffness from the updated model are very close to the test data, in which the maximum relative error decreases to 3.9% from 30.52% and the others are less than 3%, so that the design precision of aeroengine stator system with the many and wide variety of bolted joints gets a great improvement. Moreover, the proposed methods of parametric modeling and model updating for multi-characteristic responses are validated to be effective in the simulation and equivalent of the mechanical characteristics of bolted joints in complex systems like aeroengine stator system.
9
Yu, Da Zhao, Yue Liang Chen, Zhong Hu Jia, Yong Gao, and Wen Lin Liu. "Parametric Analysis Mechanical Properties of Bolted Joints." Advanced Materials Research 97-101 (March 2010): 3924–27. http://dx.doi.org/10.4028/www.scientific.net/amr.97-101.3924.
Full textAbstract:
Three-dimensional finite element model of a bolted joint has been developed in the non-linear finite element code MSC.Marc and attempts were made to validate it by comparing results with those of experiments and other finite element. Issues in modeling the contact between the joint parts, which affect the accuracy and efficiency of the model, were presented. Experimental measurements of surface strains and load transfer ratio(LTR) were compared with results from finite element analysis. The results show that three-dimensional finite element model of bolted joint can produce results in close agreement with experiment. Three-dimensional effects such as bolt titling, seconding and through-thickness variations in stress and strain are well represented by such models. Three-dimensional finite element analysis was also used to study the effects of different parameters on the mechanical behaviour of single lap bolted joints. The results show that straight hole, small bolt diameter, and big hole pitch are selected first for bolted joint if other conditions allowed, and effect of bolt material on LTR of joint is small for small load. Interference and pre-stress should be strictly controlled for bolted joints in order to attain the best fatigue capability of lap joint.
10
Guo, Tie Neng, Bin Song, Dong Liang Guo, and Zhong Qing Chen. "Dynamic Stiffness Identification of Bolted Joints." Advanced Materials Research 291-294 (July 2011): 1582–88. http://dx.doi.org/10.4028/www.scientific.net/amr.291-294.1582.
Full textAbstract:
The joint has a significant effect on the dynamic characteristic of the mechanism, and the identification of the stiffness of the joints has become a key problem. In this paper, a method is presented for identifying the dynamic characteristic of joints. An experiment is designed to test the dynamic parameter of the bolted joints specimen; the identification method, based on experiment, has a high accuracy result. By taking a specimen to experiment and identify the dynamic characteristic of joints, the relationship between the preload on the bolts and the joints stiffness is acquired. In order to validate the accuracy of the result, the FEM software is used to simulate. There are only a small discrepancy between the results of identification and simulation.
11
Eraliev, Oybek Maripjon Ugli, Yi-He Zhang, Kwang-Hee Lee, and Chul-Hee Lee. "Experimental investigation on self-loosening of a bolted joint under cyclical temperature changes." Advances in Mechanical Engineering 13, no. 8 (August 2021): 168781402110394. http://dx.doi.org/10.1177/16878140211039428.
Full textAbstract:
The most commonly used part in engineering fields is threaded fasteners. There are a lot of advantages of fasteners. One of them is that they can be easily disassembled and reused, but a bolted joint can loosen easily when a transversal load is applied. The clamp load of a bolted joint can also loosen slowly when subjected to repeated temperature changes. This paper presents an experimental investigation of the self-loosening of bolted joints under cyclical temperature variation. Experiments are carried out under several cyclical temperature changes with different bolt preloads. Rectangular threaded bolted joints with M12 × 1.75 bolts and nuts are tested in a specially designed testing apparatus. Material of bolt, nut, and plates is a stainless steel. The experimental results show that the high initial bolt preload may prevent the joint from self-loosening and the bolted joint has loosened significantly in the first cycle of temperature changes. From this investigation, the loosening of the bolted joint can be considered as a first stage self-loosening.
12
Pineda Allen, Juan Carlos, and Ching Tai Ng. "Nonlinear Guided-Wave Mixing for Condition Monitoring of Bolted Joints." Sensors 21, no. 15 (July 27, 2021): 5093. http://dx.doi.org/10.3390/s21155093.
Full textAbstract:
Bolted joints are fundamental to numerous structural components in engineering practice. Nevertheless, their failure or even their loosening can lead to insufficient performance and reduced structural safety. This study presents a theoretical development and experimental investigation into nonlinear guided-wave mixing for integrity monitoring of bolted joints in plates. Combinational harmonics generated due to nonlinear Lamb wave mixing and contact acoustic nonlinearity at the bolted joints were used to evaluate the applied torque level in the joint. The area of the power spectral density in the region of the sum combinational harmonic bandwidth is found to be highly correlated to the applied torque level at the joint. Moreover, the effect of the number of cycles and thus the time duration of the excitation is investigated. The results show that the combinational harmonics remain robust for different numbers of cycles in detecting bolt loosening. The findings presented in this study also provide physical insight into the phenomena of nonlinear Lamb wave mixing for evaluating applied torque in bolted joints, and the results help further advance the use of nonlinear guided waves for damage detection.
13
Cabaleiro, Manuel, Carlos Moutinho, Cristina González-Gaya, Elsa Caetano, and Victor Fco Rosales-Prieto. "Analysis of Stiffness of Clamped Joints versus Bolted Joints in Steel Structures by Means of Accelerometers and Shaking Table Tests." Sensors 21, no. 14 (July 13, 2021): 4778. http://dx.doi.org/10.3390/s21144778.
Full textAbstract:
This work analyzes the difference in stiffness in a steel laboratory structure using clamped joints or bolted joints and analyzes if the stiffness varies in the same way when the frame is subjected to external dynamic loads that bring the joint materials to their yield strength. To make this comparison, the differences between clamp joint and bolted joint were evaluated using a novel methodology based on the analysis of the structure’s natural frequencies from accelerometers. To perform this comparison, several laboratory tests were carried out on a frame made by clamped joints and the same frame made by bolted joints, using a set of tests on a medium-scale shake table for this purpose. The results achieved have verified the methodology used as adequate.
14
Szczęch, Marcin, and Wojciech Horak. "EXPERIMENTAL ANALYSIS OF THE LOAD CAPACITY AND REPEATABILITY OF PRELOADED BOLTED JOINTS." Tribologia 292, no. 4 (November 30, 2020): 71–77. http://dx.doi.org/10.5604/01.3001.0014.5909.
Full textAbstract:
Bolted joints are among the most widespread and most important detachable connections used in mechanical engineering and construction. The common use of this connection group is reflected in the variety of types of screw connections. There are several geometric and material factors, and consequently tribological ones, that determine the load capacity and, which is often of key importance, the repeatability of the bolted joint. The paper presents a description of the test stand and the test results of preloaded bolted joints for different lubrication conditions. The measured parameters were the breaking force value of a double lap bolted joint and its repeatability and the axial force repeatability of the bolts tightened by an electronic torque wrench.
15
Cardoso, Raphael Calazans, Brenno Lima Nascimento, Felipe de Freitas Thompson, and Sandro Griza. "Study of bolted joint axial stiffness using finite element analyses, experimental tests, and analytical calculations." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 234, no. 23 (May 23, 2020): 4671–81. http://dx.doi.org/10.1177/0954406220927066.
Full textAbstract:
The bolted joints sizing procedures shall adequately match the conditions imposed on the joint in service, to ensure high reliability designs. Therefore, this study aims to analyze the load distributions on the bolt when applying external load on bolted joints. Finite element and extensometry analyses as well as analytical calculations were performed in order to compare the magnitude of the joint overall stiffness, with respect to several available theories. The results acquired through the analytical method prescribed in the VDI 2230 standard as well as the finite element and extensometry analyses obtained great accordance. These results indicate that VDI 2230 standard adequately represents the mechanical behavior of the joint and should be used as a guideline for the reliable design of bolted joints subjected to the loading conditions of the present paper.
16
Zhao, Yongsheng, Hongchao Wu, Congbin Yang, Zhifeng Liu, and Qiang Cheng. "Interval estimation for contact stiffness of bolted joint with uncertain parameters." Advances in Mechanical Engineering 11, no. 11 (November 2019): 168781401988370. http://dx.doi.org/10.1177/1687814019883708.
Full textAbstract:
Bolted joints are elements used to create resistant assemblies in the mechanical system, whose overall performance is greatly affected by joints’ contact stiffness. Most of the researches on contact stiffness are based on certainty theory whereas in real applications the uncertainty characterizes the parameters such as fractal dimension D and fractal roughness parameter G. This article presents an interval estimation theory to obtain the stiffness of bolted joints affected by uncertain parameters. Topography of the contact surface is fractal featured and determined by fractal parameters. Joint stiffness model is built based on the fractal geometry theory and contact mechanics. Topography of the contact surface of bolted joints is measured to obtain the interval of uncertain fractal parameters. Equations with interval parameters are solved to acquire the interval of contact stiffness using the Chebyshev interval method. The relationship between the interval of contact stiffness and the uncertain parameters, that is, fractal dimension D, fractal roughness parameter G, and normal pressure, can be obtained. The presented model can be used to estimate the interval of stiffness for bolted joints in the mechanical systems. The results can provide theoretical reference for the reliability design of bolted joints.
17
Ledford, Noah, and Michael May. "Modeling of multimaterial hybrid joints under high-rate loading." Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering 234, no. 5 (April 15, 2020): 446–53. http://dx.doi.org/10.1177/0954408920919012.
Full textAbstract:
Joint failure plays a key role in determining structural stability and crash or impact response. Characterizing the joints at high loading rates is challenging as oscillations are often overlaid on the measured data, making interpretation of the results more difficult. This paper builds upon the experimental testing three different mixed-material joints using a split-Hopkinson tension bar. The correction proposed in this work is verified using a finite element model of the entire testing system. The modeling efforts also investigate the differences in a specimen only model and a model including the entire testing system. The failure mechanisms of bolted and bonded joints are investigated, where the substrate stress state is found to play a large role in determining the failure mode for bolted joints. This work lays the foundations needed to investigate the mixed-material bolted and bonded joints in detail.
18
Zhu, Kaijun, Yu Qian, J. Riley Edwards, and Bassem O. Andrawes. "Finite Element Analysis of Rail-End Bolt Hole and Fillet Stress on Bolted Rail Joints." Transportation Research Record: Journal of the Transportation Research Board 2607, no. 1 (January 2017): 33–42. http://dx.doi.org/10.3141/2607-06.
Full textAbstract:
A rail joint typically is one of the weakest elements of a track superstructure, primarily because of discontinuities in its geometric and mechanical properties and the high-impact loads induced by these discontinuities. The development of continuously welded rail has significantly reduced the number of rail joints, but many bolted joints remain installed in rail transit systems. Because of the unique loading environment of a rail transit system (especially high-frequency, high-repetition loads), defects related to bolted rail joints (e.g., joint bar failures, bolt hole cracks, and cracks in the upper fillet) continue to cause service failures and can pose derailment risks. Recent research in the Rail Transportation and Engineering Center at the University of Illinois at Urbana–Champaign has focused on investigating crack initiation in the bolt hole and fillet areas of bolted rail joints. Stress distribution was investigated at the rail-end bolt hole and upper fillet areas of standard, longer, and thicker joint bars under static loading conditions. Numerical simulations were organized into a comprehensive parametric analysis performed with finite element modeling. Preliminary results indicated that the longer joint bar performed similarly to the standard joint bar but the thicker joint bar reduced rail vertical displacement and rail upper fillet stresses compared with the standard joint bar. However, the thicker joint bar also may generate higher stresses at the rail-end bolt hole. Additionally, joint bar performance was dependent on the rail profile and bolt hole location.
19
Wang, R., A. D. Crocombe, G. Richardson, and C. I. Underwood. "Energy dissipation in spacecraft structures incorporating bolted joints with viscoelastic layers." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 222, no. 2 (February 1, 2008): 201–11. http://dx.doi.org/10.1243/09544100jaero259.
Full textAbstract:
The energy dissipation capacity of bolted joints with viscoelastic layers in a spacecraft structure was investigated. Initially, a linear spring dashpot model was used to represent the bolts in a satellite structure. A relationship was developed between the model parameters (stiffness and damping coefficient) and the viscoelastic material and geometric properties (shear modulus, loss factor, operating area, and thickness) of the actual bolted joint. This model was then developed into the non-linear domain. Experiments on bolted joints with viscoelastic layers were carried out to provide information for the non-linear joint model. These models were incorporated into a simple spacecraft model to investigate the effect on the spacecraft response. Based on these numerical analysis, it was found that the joints can dissipate much energy and the response of the spacecraft structure to vibrations during launch can be decreased significantly.
20
Gong, Hao, Jianhua Liu, and Xiaoyu Ding. "Study on the critical loosening condition toward a new design guideline for bolted joints." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 233, no. 9 (September 27, 2018): 3302–16. http://dx.doi.org/10.1177/0954406218802928.
Full textAbstract:
An understanding of conditions that trigger the loosening of bolted joints is essential to ensure joint reliability. In this study, a three-dimensional finite element model of a typical bolted joint is developed, and a new simulation method is proposed to quantitatively identify the critical transverse force for initiating loosening. This force is used to evaluate the anti-loosening capacity of bolted joints. Using the proposed simulation method, the effects of factors affecting critical loosening are systematically studied. It is found that the preload, frictional coefficients at the thread and the bearing surfaces, clamped length, and fit tolerance mainly affected loosening. When the preload and friction coefficients are increased, and the clamped length and fit tolerance are reduced, loosening is inhibited. Experiments are performed to demonstrate the reliability of the results. Finally, a suggestion is proposed to improve the design guideline VDI 2230 for bolted joints, which considers the requirement of avoiding loosening under vibrational loading.
21
Urbikain, Gorka, Jose M. Perez, Luis N. López de Lacalle, and Aritz Andueza. "Combination of friction drilling and form tapping processes on dissimilar materials for making nutless joints." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 232, no. 6 (July 27, 2016): 1007–20. http://dx.doi.org/10.1177/0954405416661002.
Full textAbstract:
In this article, a new method for the rapid and economical production of ‘nutless’ bolted joins is presented, using a combination of two hole-making techniques, namely, form drilling and form tapping. The combined method achieves a quick way for the production of threaded holes on couples of dissimilar metal alloys, as it is the case of steels and aluminium alloys. After the simultaneous form drilling on the aluminium–steel pairs and followed by form tapping, a fastener can be introduced and screwed for achieving a tight bolted joint, without any necessity of nut. However, form drilling and threading are performed consecutively in the same machine tool, reducing the whole process time. The process parameters were studied for reducing the gap between surfaces and producing a good cup for making the posterior threading. Then, mechanical testing of several test pieces resulted in a similar behaviour than traditional bolted joints. Finally, corrosion tests were performed for a better understanding of the joint manufactured. In this way, savings in time and money are derived from the application of the approach. Target markets for the new approach are the light boilermaking industry in order to eliminate either welding beads or classical bolted joints using nuts.
22
Welch, Michael. "Classical analysis of preloaded bolted joint load distributions." International Journal of Structural Integrity 9, no. 4 (August 13, 2018): 455–64. http://dx.doi.org/10.1108/ijsi-07-2017-0045.
Full textAbstract:
Purpose The purpose of this paper is to develop the understanding of how external loads are reacted through preloaded bolted joints and the interaction of the joint elements. The paper develops ideas from how to do an analysis to understanding the implications of the results. Design/methodology/approach Classical methods of analysis are applied to preloaded bolted joints, made with multiple bolts. The paper considers both the detailed analysis of bolts stresses, fatigue analysis and load-based design analysis, to demonstrate the structural integrity of preloaded bolted joints. Findings In preloaded joints the external tensile axial load and moments are mainly supported by changes in contact pressure at the faying surface. Only a small proportion of the external loads produce changes in bolt tensile stress. The bolts have a significant mean stress but experience a low working stress range. This low stress range is a factor in explaning why preloaded bolted joints have good fatigue performance. Practical implications In many cases the methods presented are adequate to demonstrate the structural integrity of joints. In some cases finite element methods may be more appropriate, and the methods discussed can be used in the validation process. Originality/value The paper brings together a number of concepts and links them into a practical design analysis process for preloaded bolted joints. Interpretation of results, within the context of design standards, is provided.
23
Pakdil, M., F. Sen, and A. Cakan. "Failure Behavior of Two Parallel Pinned/Bolted Composite Joints." Journal of Mechanics 27, no. 1 (March 2011): 121–27. http://dx.doi.org/10.1017/jmech.2011.13.
Full textAbstract:
ABSTRACTIn this study, the failure behavior of two parallel pinned/bolted composite joints was investigated, experimentally. The laminated composite plates were produced from glass fibers and epoxy matrix. During the tests, various joint geometries and ply orientations were considered to decide the optimum joint geometry and suitable stacking sequence of the laminated composite plates for two parallel pinned/bolted joints. For these reasons, the distance from the free edge of the plate to hole diameter ratio (E/D) was changed from 1 to 5, the distance between two parallel holes to hole diameter ratio (K/D) was selected as 2 and 5, the distance from the lateral edge of the plate to hole diameter ratio (N/D) was taken as 2 and 3. The laminated plates were composed from 8 laminas to stuck onto together with three different orientations as [0°2 / 30°2]s, [0°2 / 45°2]s and [0°2 / 60°2]s. The experiments involved both pinned and bolted joint. Experimental results indicate that failure behaviors of pinned/bolted composite joints are strictly influenced from both orientations of laminated plates and geometrical parameters.
24
Khan, Niaz B., Muhammad Abid, Mohammed Jameel, and Hafiz Abdul Wajid. "Joint strength of gasketed bolted pipe flange joint under combined internal pressure plus axial load with different (industrial and ASME) bolt-up strategy." Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering 231, no. 3 (October 29, 2015): 555–64. http://dx.doi.org/10.1177/0954408915614460.
Full textAbstract:
Gasketed bolted flange joints are used in process industry for connecting pressure vessels and pipes. Design procedures available in the literature mostly discuss structural strength, while sealing failure is still a big concern in industries. Similarly, limited work is found in the literature regarding performance of gasketed bolted joints under combined loading. A detailed 3D nonlinear finite element analysis is performed to study the strength and sealing of a gasketed bolted flanged pipe joint under different bolt-up strategy (Industrial and ASME) and under combined internal pressure and axial loading.
25
Stephen, JT, MB Marshall, and R. Lewis. "An investigation into contact pressure distribution in bolted joints." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 228, no. 18 (March 27, 2014): 3405–18. http://dx.doi.org/10.1177/0954406214528320.
Full textAbstract:
Bolted joints are widely used in modern engineering structures and machine designs due to their low cost and reliability when correctly selected. Their integrity depends on quantitative representation of the contact pressure distribution at the interface during design. Because of the difficulty in reaching and assessing clamped interfaces with traditional experimental methods, presently bolted joint design and evaluation is based on theoretical analysis, with assumptions to quantify pressure distribution at the clamped interface, which may not represent their true operating conditions. The present work utilises a non-intrusive ultrasonic technique to investigate and quantify the pressure distribution in bolted joints. The effect of variation in plate thickness on the contact pressure distribution at bolted interfaces under varying axial loads is investigated. While it was observed that the contact pressure at the interface increases as the applied load increases, the distance from the edge of the bolt hole at which the distribution becomes stable is independent of the applied load on the bolted joint. However, the contact pressure distribution was observed to vary with the plate thickness. Although the variation in the peak value of the average contact pressure distribution in bolted joints does not depend on the plate thickness, the distance from the edge of bolt hole at which the value of the distribution becomes stable increases as the plate thickness is increased. It was also observed that the edge of the bolt head affected the position of the peak value of the contact pressure distribution at the interface, though its effect was dependent on plate thickness. Furthermore, a model based on a Weibull distribution has been proposed to fit the experimental data and a good correlation was observed.
26
Huang, Tao, and Zhe Su. "Study on Bearing Behaviors of Bolted Joints in Composite Laminates." Advanced Materials Research 652-654 (January 2013): 1509–13. http://dx.doi.org/10.4028/www.scientific.net/amr.652-654.1509.
Full textAbstract:
An experimental investigation was conducted to determine the bearing stress of single-lap double bolted composite joints. The bearing stress of a group of specimen was presented and the relationship between the stress and strain was obtained. The experimental results show that the damage of the bolted joints was a progressive process; and the ultimate bearing stress depends not only on the laminates’ strength but also on the bolt strength. A finite element model was created based on the bolted joint specimen to simulate the loading – displacement response. The numerical results verified the experiment results qualitatively.
27
Li, Bingqi, Zhenyu Zhang, Xiaogang Wang, and Xiaonan Liu. "Investigation on cohesive zone model of bolted joint for water conveyance tunnel lining." Engineering Computations 36, no. 5 (June 10, 2019): 1449–68. http://dx.doi.org/10.1108/ec-07-2018-0310.
Full textAbstract:
Purpose The behavior of joints has a significant effect on the stability of water conveyance tunnel. The purpose of this paper is to study the contact and friction at the joint of the tunneling segment lining and establish its contact friction model. At the same time, the stress and deformation characteristics at the joint of the segment under hydrostatic load are analyzed. Design/methodology/approach In this study, the contact and friction in a bolted joint are examined using shear testing. The feasibility of the proposed model is verified by a numerical simulation of tests and a theoretical analysis. Accordingly, the effect of joints on the lining is explored under internal hydrostatic loading. Findings The results show that the openings of tunnel segments in joints gradually expand from the positions of the inner and outer edges to the location of the bolt. Moreover, the stress concentration zone is formed at the bolt. Under hydraulic loading, the opening displacement at the joint increases as the water pressure increases; nevertheless, it does not exceed engineering requirements. When the water pressure of the tunnel lining joint reaches 0.5 MPa, the opening of the joint slowly increases. When the water pressure exceeds 0.7 MPa, the opening of the joint rapidly and significantly increases. Originality/value Contact and friction in a bolted joint were examined using shear testing. A cohesive zone model of bolted joints was proposed based on test results. The influence of joint behavior on the stability of water conveyance tunnel was studied.
28
Ambarita, H., M. Daimaruya, and H. Fujiki. "Impact Fracture of Jointed Steel Plates of Bolted Joint of Cars." Applied Mechanics and Materials 566 (June 2014): 232–37. http://dx.doi.org/10.4028/www.scientific.net/amm.566.232.
Full textAbstract:
The present study is concerned with the development of a fracture criterion for the impact fracture of jointed steel plates of a lap bolted joint used in the suspension parts of a car body. For the accurate prediction of crash characteristics of car bodies by computer-aided engineering (CAE), it is also necessary to examine the behaviour and fracture of the jointed steel plates subjected to impact loads. Although the actual impact fracture of jointed steel plates of a lap bolted joint in cars is complicated, for simplifying it is classified into the shear fracture and the extractive fracture of jointed steel plates. Three kinds of steel plates, i.e., common steel with the tensile strength of 270 MPa and two high tensile strength steels with the tensile strength of 440 and 590 MPa level used for vehicles, are examined. In the impact shear test, the specimens are made of two plates and jointed by a bolt, and in the impact extractive test the specimens are made of a plate and drilled in the centre for a bolt. The impact shear test of jointed steel plates of lap bolted joints is performed using a modified split Hopkinson bar apparatus, while the impact extractive one is performed using one-bar method. Numerical simulations by a FEM code LS-DYNA are also carried out in order to understand the mechanism of shearing and extractive fractures process of jointed steel plates. The obtained results suggest that a stress-based fracture criterion may be developed for the impact shearing and extractive fractures of jointed steel plates of lap bolted joints used in a car body.
29
Wi, Jun-Hee, Kwang-Hee Lee, and Chul-Hee Lee. "Self-loosening of 3D printed bolted joints for engineering applications." MATEC Web of Conferences 185 (2018): 00029. http://dx.doi.org/10.1051/matecconf/201818500029.
Full textAbstract:
A bolt joint is a simple element that joins mechanical components. Self-loosening of bolted joints occurs due to the vibrations caused by motors and engines, resulting in the breakage of machines, and potentially serious safety problems. Recently, developments in 3D printing technologies have enabled the fabrication of detailed components. These technologies can be used for producing fasteners using 3D printed bolts. Many researchers have proposed a theoretical model for self-loosening of the bolt, and experimental studies on the self-loosening phenomenon have been advanced. However, studies on the self-loosening of 3D printed bolts have not been conducted. Therefore, it aims to confirm the self-loosening phenomenon and the safety of 3D printed bolts through experiments and finite element simulation. A lateral vibration test system is constructed and self-loosening of the bolt is evaluated by observing the axial force according to the vibration cycle by using a strain gauge. This study compared the self-loosening of 3D printed bolts and steel bolts by changing the preload and amplitude. In addition, the experimental results are verified through finite element simulation. Through this study, it is expected that 3D printed bolts will be used more frequently in situations where specially shaped bolts are needed.
30
Zhao, Shuyuan, Jianglong Dong, Chao Lv, Zhengyu Li, Xinyang Sun, and Wenjiao Zhang. "Thermal Mismatch Effect and High-Temperature Tensile Performance Simulation of Hybrid CMC and Superalloy Bolted Joint by Progressive Damage Analysis." International Journal of Aerospace Engineering 2020 (March 11, 2020): 1–14. http://dx.doi.org/10.1155/2020/8739638.
Full textAbstract:
The hybrid CMC and superalloy bolted joints have exhibited great potential to be used as thermostructural components of reusable space transportation systems, given the respective strengths of these two materials. In the high temperature excursion of the hybrid joints with the aircrafts and space vehicles, the substantial difference in thermal expansion coefficients of CMC and superalloy materials will induce complex superposition of initial assembly stress, thermal stress, and tensile stress around fastening area, which might lead to unknown failure behavior of joint structure. To address this concern, a finite element model embedded with progressive damage analysis was established to simulate the thermostructural behavior and high-temperature tensile performance of single-lap, single-bolt C/SiC composite and superalloy joint, by using the ABAQUS software. It was found that the initial stiffness of the CMC/superalloy hybrid bolted joints decreases with the rise of applied temperature under all bolt-hole clearance levels. However, the load-bearing capacity varies significantly with the initial clearance level and exposed temperature for the studied joint. The thermal expansion mismatch generated between the CMC and superalloy materials led to significant changes in the assembly preload and bolt-hole clearance as the high-temperature load is applied to the joint. The evolution in the thermostructural behavior upon temperature was then correlated with the variations in stiffness and failure load of the joints. The provided new findings are valuable for structural design and practical application of the hybrid CMC/superalloy bolted joints at high temperatures in next-generation aircrafts.
31
Yu, Da Zhao, Yue Liang Chen, Yong Gao, Wen Lin Liu, and Zhong Hu Jia. "Load Transfer Analysis of Cracked Bolted Joints." Advanced Materials Research 118-120 (June 2010): 147–50. http://dx.doi.org/10.4028/www.scientific.net/amr.118-120.147.
Full textAbstract:
Three-dimensional finite element model of a cracked bolted joint has been developed in the non-linear finite element code MSC.Marc and attempts were made to validate it by comparing results with those of experiments and other finite element. Issues in modeling the contact between the joint parts, which affect the accuracy and efficiency of the model, were presented. Experimental measurements of load transfer were compared with results from finite element analysis. The results show that three-dimensional finite element model of cracked bolted joint can produce results in close agreement with experiment. Three-dimensional effects such as bolt titling, seconding and through-thickness variations in stress and strain are well represented by such models. Three-dimensional finite element analysis was also used to study the effects of hole mod and crack on the load transfer behaviour of single lap bolted joints. The results show that hole mode has big effect on load transfer of cracked bolted joint. In the whole progress of crack growth, the load transfer through bolt 1 decrease, and almost all of the load duduction of bolt 1 transfer into blot 2 rather than into bolt 3.
32
Feyzi, M., S. Hassanifard, and A. Varvani-Farahani. "Progressive fatigue behavior of single-lap bolted laminates under different tightening torque magnitudes." Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications 234, no. 10 (June 29, 2020): 1303–12. http://dx.doi.org/10.1177/1464420720936723.
Full textAbstract:
The present paper studies fatigue damage and life of single-lap bolted joints tightened with different torque magnitudes subjected to uniaxial load cycles. The adherends were constructed from E-glass/epoxy layers using a hand layup technique and assembled by 1.5, 3, and 8 N m of applied torques. Increasing the torque magnitude benefitted the final fatigue life of the joints so that the high-cycle fatigue life of the joint sample tightened with 8 N m was as high as 10 times that of the joint tightened with 1.5 N m. In the numerical section of this study, a three-dimensional finite element analysis was employed, and the impacts of applied torques were included in the progressive damage model to assess damage and failure in the bolted joints. For the joints tightened with higher torque levels, numerical results revealed higher fatigue lives but at the cost of more delamination at the vicinity of the hole. Laminate fracture surface was investigated through scanning electron microscopy and more cracking/damage progress was evidenced in matrix, fiber, and matrix–fiber interface as composite joints experienced fatigue cycles. Experimental life data of tested joints agreed with those anticipated through the use of finite element analyses indicating the developed model as an appropriate tool in evaluating the effects of applied torques on the fatigue fracture behavior of bolted laminates.
33
Grosse, I. R., and L. D. Mitchell. "Nonlinear Axial Stiffness Characteristics of Axisymmetric Bolted Joints." Journal of Mechanical Design 112, no. 3 (September 1, 1990): 442–49. http://dx.doi.org/10.1115/1.2912628.
Full textAbstract:
A critical assessment of the current design theory for bolted joints which is based on a linear, one-dimensional stiffness analysis is presented. A detailed nonlinear finite element analysis of a bolted joint conforming to ANSI standards was performed. The finite element results revealed that the joint stiffness is highly dependent on the magnitude of the applied load. The joint stiffness changes continuously from extremely high for small applied loads to the bolt stiffness during large applied loads, contrary to the constant joint stiffness of the linear theory. The linear theory is shown to be inadequate in characterizing the joint stiffness. The significance of the results in terms of the failure of bolted joints is discussed. A number of sensitivity studies were carried out to assess the effect of various parameters on the axial joint stiffness. The results revealed that bending and rotation of the joint members, interfacial friction, and the bolt/nut threading significantly influence the axial stiffness characteristics of the bolted joint. The two-dimensional, axisymmetric finite element model includes bilinear gap elements to model the interfaces. Special orthotropic elements were used to model the bolt/nut thread interaction. A free-body-diagram approach was taken by applying loads to the outer diameter of the joint model which correspond to internal, uniformly distributed line-shear and line-moment loads in the joint. A number of convergence studies were performed to validate the solution.
34
Klajmonová, Kristýna, and Antonín Lokaj. "Round Timber Joints under Tensile Loading Perpendicular to the Grain." Advanced Materials Research 1065-1069 (December 2014): 1327–30. http://dx.doi.org/10.4028/www.scientific.net/amr.1065-1069.1327.
Full textAbstract:
This paper presents the results of static tests of non-reinforced round timber bolted joints with slotted-in steel plates loaded perpendicular to the grain. This type of joints loading is particularly widespread in truss structures. Round timber test samples series were prepared to validate the behavior of a joint loaded in tension perpendicular to the grain. The joints samples were experimentally tested in the laboratory of the Faculty of Civil Engineering VŠB TU Ostrava. The test results were compared with the calculated load-carrying capacity of joints by Johansen’s yielding theory.
35
TODA, Hitoshi. "Accident Analysis of Bolted Joints." Journal of the Japan Society for Precision Engineering 87, no. 4 (April 5, 2021): 345–48. http://dx.doi.org/10.2493/jjspe.87.345.
Full text
36
Zhang, Z., Y. Xiao, YQ Liu, and ZQ Su. "A quantitative investigation on vibration durability of viscoelastic relaxation in bolted composite joints." Journal of Composite Materials 50, no. 29 (July 28, 2016): 4041–56. http://dx.doi.org/10.1177/0021998316631810.
Full textAbstract:
Time-dependent behavior and factors affecting preload relaxation in a carbon/epoxy composite bolted joint under resonance were studied. The effect of viscoelasticity of composite material on bolt relaxation was studied quantitatively through modal analysis from the perspective of energy dissipation and stiffness degradation. Damping ratio and resonance frequency were utilized to characterize the effects of preload relaxation on structural dynamic response. The loss of preload was found to decrease with increasing initial preloads over a 10 h vibration fatigue. However, an increase in preload loss occurred as exciting frequency increases. Vibration fatigue damage was found to result in decaying stiffness and amplitude responses of the bolted joints, along with an increase in damping ratio. As a proof-of-concept study, a beam-like specimens with and without bolted joints were comparatively excited to ascertain their respective dynamic responses; results revealed that relaxation in bolted joints could be attributed to the conjunct mechanisms between viscoelastic behavior of polymer matrix composites and interface friction for different contact surfaces, where such relaxation behavior was mainly due to viscoelasticity of the joint materials.
37
Hu, Yu-Jia, Wei-Gong Guo, Cheng Jiang, Yun-Lai Zhou, and Weidong Zhu. "Looseness localization for bolted joints using Bayesian operational modal analysis and modal strain energy." Advances in Mechanical Engineering 10, no. 11 (November 2018): 168781401880869. http://dx.doi.org/10.1177/1687814018808698.
Full textAbstract:
Bayesian operational modal analysis and modal strain energy are employed for determining the damage and looseness of bolted joints in beam structures under ambient excitation. With this ambient modal identification technique, mode shapes of a damaged beam structure with loosened bolted connections are obtained based on Bayesian theory. Then, the corresponding modal strain energy can be calculated based on the mode shapes. The modal strain energy of the structure with loosened bolted connections is compared with the theoretical one without bolted joints to define a damage index. This approach uses vibration-based nondestructive testing of locations and looseness of bolted joints in beam structures with different boundary conditions by first obtaining modal parameters from ambient vibration data. The damage index is then used to identify locations and looseness of bolted joints in beam structures with single or multiple bolted joints. Furthermore, the comparison between damage indexes due to different looseness levels of bolted connections demonstrates a qualitatively proportional relationship.
38
Xu, De Liang, Wei Qing Liu, Ding Zhou, Jian Dong Ding, Ying Lei, and Wei Dong Lu. "The Study on Mechanical Properties of Single-Bolted Steel-Glulam-Steel Joints." Advanced Materials Research 255-260 (May 2011): 204–8. http://dx.doi.org/10.4028/www.scientific.net/amr.255-260.204.
Full textAbstract:
Seven groups, total of 31 single-bolted steel-glulam-steel joints, were tested for their mechanical performance. The mechanical properties of single-bolted steel-glulam-steel connection subjected to a load parallel to the grain have been studied. The failure mode and failure mechanism of bolted connections were discussed in detail. It is shown that the failure mode, bearing capacity, stiffness and ductility of the joint are mainly relative to the thickness of the glulam and the diameter of the bolt. Due to the wide application of bolted steel-glulam-steel connections in engineering, the present work can be taken as a reference in manufacture, and design of modern timber structures.
39
Sun, Ying, George Z. Voyiadjis, Weiping Hu, Fei Shen, and Qingchun Meng. "Fatigue and fretting fatigue life prediction of double-lap bolted joints using continuum damage mechanics-based approach." International Journal of Damage Mechanics 26, no. 1 (July 28, 2016): 162–88. http://dx.doi.org/10.1177/1056789516641481.
Full textAbstract:
Fatigue and fretting fatigue are the main failure mode in bolted joints when subjected to cyclic load. Based on continuum damage mechanics, an elastic–plastic fatigue damage model and a fretting fatigue damage model are combined to evaluate the fatigue property of bolted joints to cover the two different failure modes arisen at two possible critical sites. The predicted fatigue lives agree well with the experimental results available in the literature. The beneficial effects of clamping force on fatigue life improvement of the bolted joint are revealed: part of the load is transmitted by friction force in the contact interface, and the stress amplitude at the critical position is decreased due to the reduction in the force transmitted by the bolt. The negative effect of fretting damage on the bolted joint is also captured in the simulation.
40
Ramadan, T., and A. Ghobarah. "Behaviour of bolted link-column joints in eccentrically braced frames." Canadian Journal of Civil Engineering 22, no. 4 (August 1, 1995): 745–54. http://dx.doi.org/10.1139/l95-085.
Full textAbstract:
Current seismic provisions require that shear links in eccentrically braced frames be fully welded to the column flanges at the link-column joint. Since field welding may have its disadvantages, the use of bolted extended end-plate connection is examined. An experimental program is conducted to assess the response of extended end-plate connections of link-column joints in eccentrically braced frames. Six link-column joint specimens are tested using a cyclic load that represents the severe load reversals that the frame may be subjected to during strong earthquakes. The specimens are selected on the basis of different connection designs. Measurements of forces, strains, and displacements are made. Interaction curves relating the shear force and moment acting on links with semirigid connections are developed. The slip tendency and energy dissipation capacity of the different specimens are compared. On the basis of the test results, a design procedure is developed for the bolted extended end-plate link-column connection. It is concluded that bolted extended end-plate connections can be used for link-column joints of eccentrically braced frames. In properly designed connections bolt slippage was not measured even at high shear forces that are characteristic of link-column joint. Existing guidelines for the design of extended end-plate link-column joints are modified to account for the variable shear force and moment associated with links of different lengths. Key words: steel, frame, eccentric, braced, bolted, end plate, link, connection.
41
Grudziński, Paweł, and Konrad Konowalski. "Comparative Studies of the Seatings of Propulsion Plantsand Auxiliary Machinery on Chocks Made of Metal and Cast from Resin Part II. Mounting on Cast Resin Chocks." Polish Maritime Research 27, no. 1 (March 1, 2020): 126–33. http://dx.doi.org/10.2478/pomr-2020-0013.
Full textAbstract:
AbstractThis article is Part II of the paper containing a description and results of the experimental studies of the deformations, friction processes and structural damping that occur in the foundation bolted joints of propulsion plant components and auxiliary machinery installed on sea-going ships. Part I of this research work presents an analysis of the rigid mountings of machines and devices to the foundations on steel or resin chocks, and explains the need to carry out relevant research in this area. It also presents the description and results of experimental studies carried out for a foundation bolted joint with a conventionally used steel chock. Part II (this article) contains a description and results of similar studies carried out for a foundation bolted joint with a modern chock – cast from epoxy resin compound (EPY), specially developed for this purpose. Then, a comparative analysis of the results obtained for both bolted joints in question was made and the foundation chocks of the poured-in-place resin compound were demonstrated to better fulfill their technical tasks than the steel chocks traditionally used for this purpose.
42
Albrecht, Pedro, Adnan H. Sahli, and Fateh Wattar. "Fatigue Strength of Bolted Joints." Journal of Structural Engineering 113, no. 8 (August 1987): 1834–49. http://dx.doi.org/10.1061/(asce)0733-9445(1987)113:8(1834).
Full text
43
Wang, Z. Y., and Q. Y. Wang. "Preliminary Parametric Assessment of a Bolted Endplate Joint under Combined Axial Force and Cyclic Bending Moment." Advanced Materials Research 255-260 (May 2011): 718–21. http://dx.doi.org/10.4028/www.scientific.net/amr.255-260.718.
Full textAbstract:
Problems regarding the combined axial force and bending moment for the behaviour of semi-rigid steel joints under service loading have been recognized in recent studies. As an extended research on the cyclic behaviour of a bolted endplate joint, this study is performed relating to the contribution of column axial force on the cyclic behaviour of the joint. Using finite element analysis, the deteriorations of the joint performance have been evaluated. The preliminary parametric study of the joint is conducted with the consideration of flexibility of the column flange. The column axial force was observed to significantly influence the joint behaviour when the bending of the column flange dominates the failure modes. The reductions of moment resistance predicted by numerical analysis have been compared with codified suggestions. Comments have been made for further consideration of the influence of column axial load in seismic design of bolted endplate joints.
44
Urbonas, Kestutis, and Alfonsas Daniūnas. "COMPONENT METHOD EXTENSION TO STEEL BEAM‐TO‐BEAM AND BEAM‐TO‐COLUMN KNEE JOINTS UNDER BENDING AND AXIAL FORCES." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 11, no. 3 (September 30, 2005): 217–24. http://dx.doi.org/10.3846/13923730.2005.9636353.
Full textAbstract:
This paper presents an analysis of semi‐rigid beam‐to‐beam end‐plate bolted and beam‐to‐column end‐plate bolted knee joints that are subjected to bending and tension or compression axial force. Usually the influence of axial force on joint rigidity is neglected. According to EC3, the axial load, which is less than 10 % of plastic resistance of the connected member under axial force, may be disregarded in the design of joint. Actually the level of axial forces in joints of structures may be significant and has a significant influence on joint rigidity. One of the most popular practical method permitting the determination of rigidity and strength of joint is the so‐called component method. The extension of the component method for evaluating the influence of bending moment and axial force on the rigidity and strength of the joint are presented in the paper. The numerical results of calculations of rigidity and strength of beam-to-beam and beam-to-column knee joints are presented in this paper as well.
45
Cheng, Xianzhen, Hengjie Luan, Yujing Jiang, Sunhao Zhang, and Chuanyang Jia. "Experimental Study on Shear Behavior and Failure Mechanism of Bolted Heterogeneous Rock Joints under Different Anchorage Conditions." Geofluids 2021 (June 7, 2021): 1–14. http://dx.doi.org/10.1155/2021/9958352.
Full textAbstract:
Despite their frequent natural occurrence and engineering encounter, heterogeneous rock joints (rock joints with different lithological characters on both sides of the joint surface) have been studied much less systematically. To study the shear behavior and failure mechanism of bolted heterogeneous rock joints, laboratory tests were performed on the heterogeneous rock joints having different joint roughness coefficients (JRC) under different anchorage conditions. The results indicate that shear strength increases with the increase of JRC, showing exponential growth. Under the same roughness, the shear strengths of rock joints from large to small are fully grouted, end anchorage, and without anchorage. The mechanical characteristics of the bolt and joint are poorly matched under the end anchorage condition, which is easy to cause these two to be broken one by one. Under fully grouted, the extrusion force caused by the rock bolt will diffuse around the anchorage agent and will not cause partial continuous damage. The surface damage of heterogeneous rock joints increases with the increase of JRC and presents obvious heterogeneous characteristics. The shear dislocation between the blocks under shear load results in the interaction between the bolt and surrounding media. Under the action of shear force, the bolt body produced both axial and transverse deformation, which leads to breakage of anchorage agent and rock mass. Rock bolt has a significant impact on the shear behavior of the anchorage system, and the damage of the rock bolt to rock mass should be considered in rock engineering reinforcement design.
46
Yao, Xingyu, Jianjun Wang, and Xue Zhai. "Research and application of improved thin-layer element method of aero-engine bolted joints." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 231, no. 5 (May 9, 2016): 823–39. http://dx.doi.org/10.1177/0954410016643978.
Full textAbstract:
A new dynamic modeling method called the improved thin-layer element method is proposed to apply to the aero-engine bolted joints. The thin-layer elements are partitioned based on the interface contact stress distribution. In addition, the material parameters of the partitioned thin-layer elements are determined by the bolted joints stiffness technique and the fractal contact theory without the experimental results, which allows the engineer to estimate the dynamic characteristics of whole structure before the physical prototype is available. First, the modeling principles of the improved thin-layer element method are studied and the bolted joints stiffness is analyzed. Next, the material parameters of the partitioned thin-layer elements are determined on the basis of the interface contact stress distribution characteristics of the bolted joints. Finally, this method is applied to the simulative casing bolted joints structure and the results are compared with the experimental results in order to verify the proposed method. The results indicate that the improved thin-layer element method is more accurate than the thin-layer elements method, and the material parameters of the partitioned thin-layer elements can be expressed by the structural parameters of the aero-engine bolted joints without updating based on the experiment.
47
Klajmonová, Kristýna, and Antonín Lokaj. "Round Timber Bolted Joints with Mechanical Reinforcement." Advanced Materials Research 838-841 (November 2013): 629–33. http://dx.doi.org/10.4028/www.scientific.net/amr.838-841.629.
Full textAbstract:
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 VŠB-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.
48
Cheng, Liang, Qing Wang, and Yinglin Ke. "Experimental and numerical analyses of the shimming effect on bolted joints with nonuniform gaps." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 233, no. 11 (October 30, 2018): 3964–75. http://dx.doi.org/10.1177/0954406218809139.
Full textAbstract:
In order to investigate the effect of shim compensation for nonuniform gaps in aircraft assembly, the influence of the shims with different material and parameters on bolted joints is studied in this paper. According to the real material and assembly conditions of the aircraft joint structures, the specimen and experiment are designed to obtain the tensile performance of the joint structures with different shims. A three-dimensional finite element model, which incorporates the Johnson–Cook material property of the alloys, traction-separation law of liquid shims, contact relationships between the joint elements, and boundary conditions of the tensile process, is established with the specimen configurations. After validating through comparing with the experimental results, the modeling method is adopted to simulate the tensile response of the bolted joints with shims. Furthermore, both the influence of the shim material and thickness on the mechanical behaviors of bolted joints is investigated in detail. Shims can considerably reduce the assembly stress of joint structures and improve the joint stiffness and load capacity, and this effect is more remarkable with the increase of gap values. Liquid shims improve the joint stiffness due to its cohesive ability, while solid shims improve the joint load capacity. Hybrid shims possess a composite shimming effect of liquid and solid shims. Whatever the shim material is applied, the joint stiffness and strength drop with the growth of shim thickness, so strict deviation control method should be taken to ensure the assembly gaps as small as possible. The research results enhance the knowledge of shimming effect on joint structures, and thus offer positive guidance for practical application in aircraft assembly.
49
Czachor, Robert P. "Unique Challenges for Bolted Joint Design in High-Bypass Turbofan Engines." Journal of Engineering for Gas Turbines and Power 127, no. 2 (April 1, 2005): 240–48. http://dx.doi.org/10.1115/1.1806453.
Full textAbstract:
Bolted joints are used at numerous locations in the rotors and carcass structure of modern aircraft turbine engines. This application makes the design criteria and process substantially different from that used for other types of machinery. Specifically, in addition to providing engine alignment and high-pressure gas sealing, aircraft engine structural joints can operate at high temperatures and may be required to survive very large applied loads which can result from structural failures within the engine, such as the loss of a fan blade. As engine bypass ratios have increased in order to improve specific fuel consumption, these so-called “Ultimate” loads increasingly dominate the design of bolted joints in aircraft engines. This paper deals with the sizing and design of both bolts and lever flanges to meet these demanding requirements. Novel empirical methods, derived from both component test results and correlated analysis have been developed to perform strength evaluation of both flanges and bolts. Discussion of analytical techniques in use includes application of the LS-DYNA™ code for modeling of high-speed blade impact events as related to bolted joint behavior.
50
Zhang, Jing, Zhi-Fang Liu, Yong Xu, Mai-Li Zhang, and Liu-Cheng Mo. "Cyclic Behavior and Modeling of Bolted Glulam Joint with Cracks Loaded Parallel to Grain." Advances in Civil Engineering 2021 (March 11, 2021): 1–16. http://dx.doi.org/10.1155/2021/6612886.
Full textAbstract:
Under varying humidity and temperature conditions, with the constraint of metal fasteners to wood shrinkage, cracks along the bolt lines are generally observed in bolted glulam joints. A three-dimensional (3D) numerical model was established in software package ANSYS to investigate the cyclic behavior of bolted glulam joints with local cracks. A reversed cyclic loading was applied in the parallel-to-grain direction. The accuracy of numerical simulation was proved by comparison with full-scale experimental results. Typical failure modes were reproduced in the numerical analysis with the application of wood foundation zone material model and cohesive zone material model. The effect of crack number and length on the hysteretic behavior of bolted glulam joints was quantified by a parametric study. It was found that initial cracks impair the peak capacity and elastic stiffness of bolted glulam joints significantly. More decrease in capacity was observed in joints with more cracks, and longer cracks affect elastic stiffness more dramatically. Moreover, with the existence of initial cracks, the energy dissipated and equivalent viscous damping ratio of bolted joints are reduced by 24% and 13.3%, respectively.