Journal articles: 'Joint geometry'

1

Ayaz, Yaşar, and Çitil Şerif. "Mechanical behavior of butt curved adhesive joints subjected to bending." Materials Testing 63, no. 7 (July 1, 2021): 639–44. http://dx.doi.org/10.1515/mt-2020-0089.

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Abstract Factors such as the surface geometry of a joint, the direction of the applied load, and the type of adhesive used have a great influence on the strength of a joint in adhesive bonding. In adhesively bonded joints (ABJ), it is possible to improve surface geometry by forming various geometric surfaces. ABJs are not very resistant to peeling stress, thus requiring that a bonding model be analyzed according to the direction of the applied load to prevent peeling stress. In this study, a butt curved joint was prepared from aluminum plates (A2024-T3) to improve the surface geometry of the joint. The mechanical behavior of the joints in three-dimensions and subjected to bending were investigated depending on an increase in the curvature radius. The adhesive DP810 was used for bonding. The finite element analysis was performed in ANSYS and cohesive zone modeling was used for a simulation of the damage growth in the adhesive layer. The results of bilinear and exponential models were found to be more appropriate to the experimental results. When the radius of curvature increases, the damage load carried decreases in the butt curved lap joints. It was seen that decreases in the curvature radius significantly decrease normal stress.

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COMAN, Calin-Dumitru. "Influence of Geometry on Failure Modes of Hybrid Metal-Composite Protruding Bolted Joints." INCAS BULLETIN 13, no. 3 (September 4, 2021): 29–44. http://dx.doi.org/10.13111/2066-8201.2021.13.3.3.

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This article presents the influence of joint geometry on the damage mode in the CFRP (Carbon Fiber Reinforced Polymer) composite plate of the single-lap, protruding, hybrid metal-composite joints. A detailed 3D finite element model incorporating geometric, material and friction-based contact full nonlinearities is developed to numerically investigate the geometry effects on the progressive damage analysis (PDA) of the orthotropic material model. The PDA material model integrates the nonlinear shear response, Hashin-tape failure criteria and strain-based continuum degradation rules being developed using the UMAT user subroutine in Nastran commercial software. In order to validate the geometry effects on the failure modes of the joints with hexagonal head bolts, experiments were conducted using the SHM (Structural Health Monitoring) technique. The results showed that the plate geometry is an important parameter in the design process of an adequate bolted joint and its effects on damage initiation and failure modes were quite accurately predicted by the PDA material model, which proved to be computational efficient and can predict failure propagation and damage mechanism in hybrid metal-composite bolted joints.

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Dershowitz, W. S., and H. H. Einstein. "Characterizing rock joint geometry with joint system models." Rock Mechanics and Rock Engineering 21, no. 1 (1988): 21–51. http://dx.doi.org/10.1007/bf01019674.

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Shiba, Ryoichi, Charles Sorbie, David W. Siu, J. Timothy Bryant, T. Derek V. Cooke, and Hendrik W. Wevers. "Geometry of the humeroulnar joint." Journal of Orthopaedic Research 6, no. 6 (November 1988): 897–906. http://dx.doi.org/10.1002/jor.1100060614.

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Chan, Ting On, Linyuan Xia, Derek D. Lichti, Yeran Sun, Jun Wang, Tao Jiang, and Qianxia Li. "Geometric Modelling for 3D Point Clouds of Elbow Joints in Piping Systems." Sensors 20, no. 16 (August 16, 2020): 4594. http://dx.doi.org/10.3390/s20164594.

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Pipe elbow joints exist in almost every piping system supporting many important applications such as clean water supply. However, spatial information of the elbow joints is rarely extracted and analyzed from observations such as point cloud data obtained from laser scanning due to lack of a complete geometric model that can be applied to different types of joints. In this paper, we proposed a novel geometric model and several model adaptions for typical elbow joints including the 90° and 45° types, which facilitates the use of 3D point clouds of the elbow joints collected from laser scanning. The model comprises translational, rotational, and dimensional parameters, which can be used not only for monitoring the joints’ geometry but also other applications such as point cloud registrations. Both simulated and real datasets were used to verify the model, and two applications derived from the proposed model (point cloud registration and mounting bracket detection) were shown. The results of the geometric fitting of the simulated datasets suggest that the model can accurately recover the geometry of the joint with very low translational (0.3 mm) and rotational (0.064°) errors when ±0.02 m random errors were introduced to coordinates of a simulated 90° joint (with diameter equal to 0.2 m). The fitting of the real datasets suggests that the accuracy of the diameter estimate reaches 97.2%. The joint-based registration accuracy reaches sub-decimeter and sub-degree levels for the translational and rotational parameters, respectively.

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Djarot, Darmadi B., Femiana Gapsari, Osmar Buntu Lobo, and Firman Mangasa Simanjuntak. "Stress Corrosion Cracking Threshold for Dissimilar Capacitive Discharge Welding Joint with Varied Surface Geometry." Applied Sciences 10, no. 6 (March 23, 2020): 2180. http://dx.doi.org/10.3390/app10062180.

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Stress corrosion cracking (SCC) is known as a major factor that should be considered in the assessment of welding joint structure integrity. Despite the promising and wide application of dissimilar metal joints, the currently available SCC mitigation technique of dissimilar metal joints is not adequate. The challenge is to obtain a good joint while different melting points exist. This article reports a novel SCC mitigation method on a brass–steel dissimilar metal joint by modifying the geometry of the surface. It is evidenced that the sharpened steel (α1 specimen) significantly improves the SCC resilience of the joint. The evaluation of SEM/EDS photos reveals that the α1 geometry induces a smaller pore area around brass–steel micro-joint interfaces which in turn produces stronger joints.

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Lyu, Naesung, and Kazuhiro Saitou. "Decomposition-Based Assembly Synthesis of Space Frame Structures Using Joint Library." Journal of Mechanical Design 128, no. 1 (November 25, 2004): 57–65. http://dx.doi.org/10.1115/1.1909203.

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This paper presents a method for identifying the optimal designs of components and joints in the space frame body structures of passenger vehicles considering structural characteristics, manufacturability, and assembleability. Dissimilar to our previous work based on graph decomposition, the problem is posed as a simultaneous determination of the locations and types of joints in a structure and the cross sections of the joined structural frames, selected from a predefined joint library. The joint library is a set of joint designs containing the geometry of the feasible joints at each potential joint location and the cross sections of the joined frames, associated with their structural characteristics as equivalent torsional springs obtained from the finite element analyses of the detailed joint geometry. Structural characteristics of the entire structure are evaluated by finite element analyses of a beam-spring model constructed from the selected joints and joined frames. Manufacturability and assembleability are evaluated as the manufacturing and assembly costs estimated from the geometry of the components and joints, respectively. The optimization problem is solved by a multiobjective genetic algorithm using a direct crossover. A case study on an aluminum space frame of a midsize passenger vehicle is discussed.

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Kulatilake, Pinnaduwa H. S. W., Hasan Ucpirti, and Ove Stephansson. "Effects of finite-size joints on the deformability of jointed rock at the two-dimensional level." Canadian Geotechnical Journal 31, no. 3 (June 1, 1994): 364–74. http://dx.doi.org/10.1139/t94-044.

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A numerical decomposition technique, which has resulted from a linking between joint-geometry modeling and generation schemes, and a distinct element code (UDEC), is used to study the effect of joint-geometry parameters of finite-size joints on the deformability properties of jointed rock at the two-dimensional (2D) level. The influence of joint-geometry parameters such as joint density, ratio of joint size to block size, and joint orientation on the deformability of jointed rock is shown. Relations are established between deformability properties of jointed rock and fracture-tensor parameters. An incrementally linear elastic, anisotropic constitutive model is developed to represent the prefailure mechanical behaviour of jointed rock at the 2D level. This constitutive model has captured the anisotropic, scale-dependent behaviour of jointed rock. In this model, the effect of the joint-geometry network in the rock mass is incorporated in terms of fracture-tensor components. Some insight is given related to estimation of representative elementary volumes for deformability properties of jointed rock. Key words : rock masses, deformability, distinct element method, fracture tensor, anisotropy, scale effects.

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9

Li, De Zhi, Li Han, Mike Shergold, Martin Thornton, and Geraint Williams. "Influence of Rivet Tip Geometry on the Joint Quality and Mechanical Strengths of Self-Piercing Riveted Aluminium Joints." Materials Science Forum 765 (July 2013): 746–50. http://dx.doi.org/10.4028/www.scientific.net/msf.765.746.

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Due to the drive from legislations, fuel efficiency, and CO2 emission, the application of aluminium lightweight structures in automotive industry have been increased significantly. Self piercing riveting (SPR) has been one of the major joining technologies for aluminium structures due to its advantages to some traditional joining technologies. There are some standard parameters that will influence the joint quality and mechanical strengths of an SPR joint. However, even for the same parameters used, sometimes the joint quality and mechanical strengths of SPR joints could still be significantly different, which may cause joint failure or strength reduction. One reason found is the variation of rivet specifications between different batches. In this paper, the influence of rivet tip geometry on the joint quality and mechanical strengths was studied. The results showed that rivets with sharper tips flared more during riveting process, and joints with sharper rivets had higher lap shear strength; however, the influence of rivet geometry on T peel strength could be different for different rivets, and rivet tip geometry did not have an obvious influence on joint fatigue strengths.

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Reid, M. D., M. S. Imbabi, and D. Coutellier. "Effects of Joint Geometry on Response of Asphaltic Plug Joints." Journal of Transportation Engineering 124, no. 4 (July 1998): 311–18. http://dx.doi.org/10.1061/(asce)0733-947x(1998)124:4(311).

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11

Carson, M., A. Leardini, F. Catani, and J. J. O'Connor. "Geometry of the first metatarsophalangeal joint." Journal of Biomechanics 31 (July 1998): 29. http://dx.doi.org/10.1016/s0021-9290(98)80060-2.

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SOSLOWSKY, LOUIS J., EVAN L. FLATOW, LOUIS U. BIGLIANI, and VAN c. MOW. "Articular Geometry of the Glenohumeral Joint." Clinical Orthopaedics and Related Research &NA;, no. 285 (December 1992): 181???190. http://dx.doi.org/10.1097/00003086-199212000-00023.

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13

Yoshioka, Yuki, David W. Siu, T. Derek V. Cooke, J. T. Bryant, and Urs Wyss. "Geometry of the first metatarsophalangeal joint." Journal of Orthopaedic Research 6, no. 6 (November 1988): 878–85. http://dx.doi.org/10.1002/jor.1100060612.

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14

Wang, Min, Dichuan Zhang, and Jainping Fu. "Experimental evaluation of seismic response for reinforced concrete beam–column knee joints with irregular geometries." Advances in Structural Engineering 19, no. 12 (July 28, 2016): 1889–901. http://dx.doi.org/10.1177/1369433216649388.

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Regular reinforced concrete beam–column knee joints are typically framed by beams and columns with similar heights. However, complexities in modern architecture layouts may result in irregular geometries for the knee joint. The irregular geometry refers to significant differences in the height for the beam and the column framing into the joint. For example, the height of the beam is considerably larger than that of the column, and vice versa. Seismic performance and behavior for the regular knee joint have been well examined through previous experimental research. However, the knee joint with irregular geometry (termed here as irregular knee joint) may have different seismic behaviors compared to the regular knee joint because the irregular geometry can produce different demands, stiffness, strength, and reinforcing bond conditions. Therefore, this article evaluates seismic behavior of the irregular knee joint including failure mode, strength and stiffness degradation, deformation capacity, bond-slip of reinforcement, and energy dissipation capacity through four large-scale static cyclic tests. The test results show that in general the irregular knee joint designed to the current code has low seismic capacity due to poor bond conditions of the reinforcement inside the joint.

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15

Özes, Çiçek, and Özgen Aydin. "Analysis of Sandwich T-Joints under Compression Loads in Marine Applications." Advanced Composites Letters 18, no. 3 (May 2009): 096369350901800. http://dx.doi.org/10.1177/096369350901800301.

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This paper deals with the analysis of sandwich T-joints in terms of buckling loads, which are used in marine applications. Buckling loads have been investigated experimentally and numerically. Loading is applied as uniform axial compression. The GRP/PVC sandwich composite T- joints have been manufactured in six different geometries. Numerical and experimental results both show that the geometry of the T-joint area affects the buckling loads. It has been observed that failure mode is the same in all of the joint types, which is core shear. Stress distributions in T-joints have also been investigated under buckling loads and also for a constant compression load. It is seen that T-joint geometry has an effect on stress distributions obtained under buckling loads.

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16

Guo, Jiajie, Zihang Wang, Jianyong Fu, and Kok-Meng Lee. "Articular Geometry Reconstruction for Knee Joint with a Wearable Compliant Device." Robotica 37, no. 12 (June 17, 2019): 2104–18. http://dx.doi.org/10.1017/s0263574719000778.

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SummaryNonlinear articular geometries of biological joints have contributed to highly agile and adaptable human-body motions. However, human–machine interaction could potentially distort natural human motions if the artificial mechanisms overload the articular surfaces and constrain biological joint kinematics. It is desired to better understand the deformable articular geometries of biological joints in vivo during movements for design and control of wearable robotics. An articular geometry reconstruction method is proposed to measure the effective articular profile with a wearable compliant device and illustrated with its application to knee-joint kinematic analysis. Regarding the joint articulation as boundary constraints for the compliant mechanism, the equivalent articular geometry is constructed from the beam deformations driven by knee motions, where the continuous deformations are estimated with strain data from the embedded sensors. Both simulated analysis and experimental validation are presented to justify the proposed method.

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Leon, Roberto, and James O. Jirsa. "Bidirectional Loading of R.C. Beam-Column Joints." Earthquake Spectra 2, no. 3 (May 1986): 537–64. http://dx.doi.org/10.1193/1.1585397.

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Fourteen reinforced concrete beam-column joint subassemblages were tested to investigate the effects of load history, beam reinforcement size, beam geometry and floor slabs on joint behavior under cyclic bidirectional load reversals. The full-scale specimens were loaded biaxially to simulate the worst loading condition on the joints of a multi-story ductile moment-resisting frame. The tests showed that biaxial effects can have a significant impact on joint behavior due to the deterioration of column strength, that the beam and slab geometry can significantly affect the joint shear response, and that bond conditions and column-to-beam flexural capacity ratio control the design of such subassemblages.

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Ronsky, J. L., S. K. Boyd, D. D. Lichti, M. A. Chapman, and K. Sˇalkauskas. "Precise Measurement of Cat Patellofemoral Joint Surface Geometry With Multistation Digital Photogrammetry." Journal of Biomechanical Engineering 121, no. 2 (April 1, 1999): 196–205. http://dx.doi.org/10.1115/1.2835104.

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Three-dimensional joint models are important tools for investigating mechanisms related to normal and pathological joints. Often these models necessitate accurate three-dimensional joint surface geometric data so that reliable model results can be obtained; however, in models based on small joints, this is often problematic due to limitations of the present techniques. These limitations include insufficient measurement precision, the requirement of contact for the measurement process, and lack of entire joint description. This study presents a new non-contact method for precise determination of entire joint surfaces using multistation digital photogrammetry (MDPG) and is demonstrated by determining the cartilage and subchondral bone surfaces of the cat patellofemoral (PF) joint. The digital camera–lens setup was precisely calibrated using 16 photographs arranged to achieve highly convergent geometry to estimate interior and distortion parameters of the camera–lens setup. Subsequently, six photographs of each joint surface were then acquired for surface measurement. The digital images were directly imported to a computer and newly introduced semi-automatic computer algorithms were used to precisely determine the image coordinates. Finally, a rigorous mathematical procedure named the bundle adjustment was used to determine the three-dimensional coordinates of the joint surfaces and to estimate the precision of the coordinates. These estimations were validated by comparing the MDPG measurements of a cylinder and plane to an analytical model. The joint surfaces were successfully measured using the MDPG method with mean precision estimates in the least favorable coordinate direction being 10.3 μm for subchondral bone and 17.9 μm for cartilage. The difference in measurement precision for bone and cartilage primarily reflects differences in the translucent properties of the surfaces.

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Sadowski, T., and E. Zarzeka-Raczkowska. "Hybrid Adhesive Bonded and Riveted Joints – Influence of Rivet Geometrical Layout on Strength of Joints / Połączenia Hybrydowe Klejowo-Nitowe - Wpływ Geometrii Rozmieszczenia Nitów Na Wytrzymałość Połączeń." Archives of Metallurgy and Materials 57, no. 4 (December 1, 2012): 1127–35. http://dx.doi.org/10.2478/v10172-012-0126-0.

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The hybrid adhesive bonded and riveted joints have wider and wider application in different branches of engineering: aerospace, mechanical, civil etc. The hybrid joints’ strength is 1.5 to 3 times higher than only adhesive bonded joints’ strength. The hybrid joints characterize higher reliability during long-term working. In this article we present the influence of rivets’ lay-out geometry on the hybrid adhesive bonded/riveted joints response to mechanical loading. Experimental research was carried using 3-D digital image correlation system ARAMIS. This system enables monitoring of the deformation processes of the hybrid joint specimen up to failure. We analysed the state of deformation of the adhesive bonded double-lap joints reinforced by different numbers of rivets. The hybrid joint specimens were subjected to the uniaxial tensile test. Moreover, the influence of geometry of individual number of rivets’ layout (rivets arranged in one or more rows) for hybrid joint strength was studied. Experimental research was completed and supported by the computer simulations of the whole deformation processes of metal layers (aluminum), adhesive layers and rivets. Numerical simulations were conducted with the ABAQUS programme. The analysis of stress concentrations in different parts of the hybrid joint and their behaviour up to failure were investigated. Finally, the analysis and the comparison of the obtained results confirmed the influence of rivets’ lay-out geometry not only on rivets joints but also on the hybrid adhesive bonded/riveted joints.

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Niklas, Karol. "Search for optimum geometry of selected steel sandwich panel joints." Polish Maritime Research 15, no. 2 (April 1, 2008): 26–31. http://dx.doi.org/10.2478/v10012-007-0061-6.

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Search for optimum geometry of selected steel sandwich panel joints Application of steel sandwich panels to ship structures requires many problems to be solved. Joints between the panels as well as those between the panels and other structures is one of the more difficult problems associated with the structures in question. This paper presents the searching for process of optimum geometry of a panel-to-panel joint of longitudinal arrangement, performed by means of the ANSYS software. A configuration was searched for of parameters which can ensure as-low-as possible values of geometrical stress concentration coefficients at acceptable mass and deformations of the structure. Analysis of the obtained results made it possible to propose the optimum geometry of the considered joint.

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Jayabalakrishnan, D., and M. Balasubramanian. "Friction Stir Welding of Dissimilar Butt Joints with Novel Joint Geometry." Acta Physica Polonica A 133, no. 1 (January 2018): 94–100. http://dx.doi.org/10.12693/aphyspola.133.94.

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Barrans, Simon, and H. E. Radhi. "Determining a Robust, Pareto Optimal Geometry for a Welded Joint." Advanced Materials Research 1016 (August 2014): 39–43. http://dx.doi.org/10.4028/www.scientific.net/amr.1016.39.

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Multi-criteria optimization problems are known to give rise to a set of Pareto optimal solutions where one solution cannot be regarded as being superior to another. It is often stated that the selection of a particular solution from this set should be based on additional criteria. In this paper a methodology has been proposed that allows a robust design to be selected from the Pareto optimal set. This methodology has been used to determine a robust geometry for a welded joint. It has been shown that the robust geometry is dependent on the variability of the geometric parameters.

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Lu, Chao, and Mei Ling Xia. "Finite Element Modeling of the Geometry Size Effect for Adhesive Joints Strength." Advanced Materials Research 129-131 (August 2010): 1212–16. http://dx.doi.org/10.4028/www.scientific.net/amr.129-131.1212.

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Based on 3D elastic-plastic finite element method (FEM), the geometry size effect on strength in aluminum alloy adhesive joints is presented in this paper. The numerical and experimental results show that with the adhesive thickness increased, the adhesive joint strength first increases then decreases, and in a certain range, with the adhesive thickness increased, the adhesive joint strength is nonlinear to the overlap length but linear to the overlap area. In the case of the same overlap area, the adhesive joint strength can be increased by increasing overlap length and decreasing overlap width.

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Kim, Jinho, Dan Zollinger, and Seunghyun Lee. "Experimental Study on the Design and Behavior of Concrete Pavement Joint Sealants." Transportation Research Record: Journal of the Transportation Research Board 2675, no. 6 (February 12, 2021): 369–79. http://dx.doi.org/10.1177/0361198121993472.

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Joints in concrete pavement are intended to provide freedom of movement in a concrete slab relative to the volumetric effects. Changes such as this can occur owing to drying shrinkage, temperature changes, and moisture differences that develop within the slab. A key reason to seal the rigid pavement joints is to prevent, or at least reduce, the amount of water from rainfall events infiltrating the pavement structure, which can ultimately contribute to subbase erosion, loss of support, and the build-up of a fine, incompressible material on the face of the joint. The strength of the joint sealant bond and stress of the interface between the sealant and the face of the joint reservoir play important roles in joint sealant failure. Thus, in this research, experimental coupling tests were conducted to investigate the geometric characteristics of the sealant/joint reservoir design. The stress–strain relationship on the interface was investigated according to its geometry, both with regard to the shape factor (SF) and the degree of curvature (DoC). The SF and DoC were evaluated through a tensile test of the joint sealant based on these geometric characteristics. Also discussed are the shape factors (SFs) of the joint sealant currently being recommended, the SF most appropriate for a narrow-width joint, and the surface finish of the joint sealant. Based on this study, the effects of sealant geometries (i.e., SF and DoC) should be considered during design and installation. Also, further research into more realistic SFs for narrow-width joints and self-leveling sealants is recommended.

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Bardell, N. S., D. Brown, P. D. Shearn, D. P. Turner, J. R. Longbourne, and R. J. Traxson. "The Development of MURJ-3D: A Modular, Universal, Re-Configurable Joint for 3-D Space Frame Applications." International Journal of Space Structures 12, no. 2 (June 1997): 89–100. http://dx.doi.org/10.1177/026635119701200204.

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Currently available joints used for constructing 3-D lattice space-frames effectively prescribe the geometry of the resulting framework and favour regular, repetitive structural geometric forms; to embrace more general geometric forms requires costly, individually-tailored, joints to be made. This paper describes a new, modular, universal, reconfigurable, joint (MURJ-3D) which has been designed specifically to overcome such problems, and hence to permit the construction of both regular and irregular framework geometries with equal facility. Each MURJ-3D acts as a structural node in any general 3-D space-frame by joining together a large number of lattice members whose longitudinal axes all coincide at a point in space. The exact number of lattice members that can be attached to a single MURJ-3D is not specified, but the capacity of the joint is such that the number of available connections is likely to exceed the maximum number of members required in any given application. The location of the connections is, for all practical purposes, infinitely variable over the surface of a sphere. The MURJ-3D is designed to permit subsequent full reconfiguration of the framework member geometry, including the addition and/or removal of individual members; its application to temporary structures, or those requiring in-situ erection, is particularly germane. The concept presented here is validated using a design, build and test schedule, which clearly demonstrates the general efficacy of the joint.

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Selbie, W. Scott, Lei Zhang, William S. Levine, and Christy L. Ludlow. "Using joint geometry to determine the motion of the cricoarytenoid joint." Journal of the Acoustical Society of America 103, no. 2 (February 1998): 1115–27. http://dx.doi.org/10.1121/1.421223.

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Gao, Quanxue, Haijun Zhang, Xiaojing Yang, Jingjing Liu, and Yamin Liu. "Joint geometry and variability for image recognition." Neurocomputing 99 (January 2013): 241–49. http://dx.doi.org/10.1016/j.neucom.2012.06.027.

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Lundquist, Christian, and Thomas B. Schön. "Joint ego-motion and road geometry estimation." Information Fusion 12, no. 4 (October 2011): 253–63. http://dx.doi.org/10.1016/j.inffus.2010.06.007.

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Eidehall, Andreas, Jochen Pohl, and Fredrik Gustafsson. "Joint road geometry estimation and vehicle tracking." Control Engineering Practice 15, no. 12 (December 2007): 1484–94. http://dx.doi.org/10.1016/j.conengprac.2007.02.010.

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COMAN, Calin-Dumitru. "The Influence of Geometry on Failure Modes of Countersunk Bolted Hybrid Joints." INCAS BULLETIN 12, no. 2 (June 5, 2020): 19–34. http://dx.doi.org/10.13111/2066-8201.2020.12.2.3.

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This paper presents a numerical study for the influence of geometry on the damage initiation and growth in the CFRP (Carbon Fiber Reinforced Polymer) laminated plate of the hybrid metal-composite countersunk bolted joints. A detailed 3D finite element model incorporating material and friction-based contact full nonlinearities is developed to investigate the geometry effects on the failure modes of the hybrid metal-composite bolted joints. The material model for CFRP joint counterpart integrates nonlinear shear response for unidirectional laminae, Hashin-type failure criteria and strain-based continuum degradation rules which were developed using the UMAT user subroutine in MSC. Patran-Nastran (MSC. Software Corporation Inc.) commercial software. Experiments were conducted in order to validate the nonlinear progressive damage analysis (PDA) results on the failure modes of the joints with countersunk bolts. The numerical and experimental results showed that the joint geometry parameter defined by the ratio between the plates width and hole diameter has an important influence in designing phase of a reliable bolted joint and its effects on damage initiation and failure modes were quite accurately predicted by the numerical model, which proved to be computational efficient and could predict damage mechanisms in hybrid metal-composite countersunk bolted joints.

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Yang, Wendong, Guizhi Li, PG Ranjith, and Lindong Fang. "An experimental study of mechanical behavior of brittle rock-like specimens with multi-non-persistent joints under uniaxial compression and damage analysis." International Journal of Damage Mechanics 28, no. 10 (February 19, 2019): 1490–522. http://dx.doi.org/10.1177/1056789519832651.

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The mechanical behavior of jointed rock masses significantly affects the stability of rock engineering applications. In this paper, the peak strength, Young's modulus and failure patterns of brittle rock-like specimens with multi-non-persistent joints under uniaxial compression are investigated. The joint geometry is defined by four factors: joint angle, spacing, joint length, and rock bridge length. The experiment results show that the joint angle has the greatest influence on the peak strength and Young's modulus of specimens, followed by joint length. A damage mechanical theory is adopted which deals with some sets of joints distributed in rock masses. Based on the geometrical distribution of joints, a macro damage model which considers the influence of the normal vector and area density of joints is used to describe the joints. The peak strength and Young's modulus of jointed specimens predicted by the damage mechanics method reflect the trend of the experimental results, which proves the influence of initial geometric damage of joints on the peak strength and Young's modulus of jointed specimens. The initial geometric damage of joints is mainly induced by the joint area density. Finally, from the micro damage aspect, to analyze the damage evolution and strain softening process of jointed rock masses, a modified numerical model (damage strainsofting model) on the basis of secondary development in fast Lagrangian analysis of Continua is proposed to simulate the fracture development of jointed rock masses. The peak strengths, Young's modulus and failure modes of rock specimens with non-persistent joints under uniaxial compressions are simulated and compared with the results obtained from the lab experiments indicating that the model is capable to replicate the physical processes.

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Xu, Li Xin, and Yun Cheng Han. "A method for contact analysis of revolute joints with noncircular clearance in a planar multibody system." Proceedings of the Institution of Mechanical Engineers, Part K: Journal of Multi-body Dynamics 230, no. 4 (August 3, 2016): 589–605. http://dx.doi.org/10.1177/1464419316644880.

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Journal bearings are generally used to comprise a revolute joint in mechanical systems. Noncircularity and clearance in journal bearing are obvious due to a long time of nonuniform wear. In this regard, a method of analyzing the contact in revolute joints with noncircular clearances in a multibody system is proposed. The revolute joint with noncircular clearance is assumed to be constituted by an elliptic bore and a pin. The method described is not representative of an elliptic bore journal bearing in a detailed manner. This method involves discretizing the geometric profile of the bushing of the revolute joint. By analyzing the relative separations between the discrete points and the geometric center of the pin, the contact area between the bushing and the pin can be judged and the maximum contact depth obtained. Compared with traditional methods, the proposed method has the advantage that it can be used to analyze noncircular contact problems in revolute joints with a clearance. A slider–crank mechanism is used as an example to compare the effects of the geometrical properties of circular and noncircular (elliptical) revolute joints with clearance on the dynamic response of the mechanisms. The results show that clearance joints with noncircular geometry predominantly affect the dynamic stability of a high-speed mechanism. Moreover, the efficiency of the contact analysis and model solving precision are strongly dependent on the number of discrete points in the geometric profile of the joint elements. The size of the joint clearance has a small effect on the solving efficiency of the model.

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Khalid, Asad A. "Effect of Interface Geometry on Strength of Single Lap Adhesive Joint of Sisal-Glass/Epoxy Laminates." Key Engineering Materials 858 (August 2020): 20–26. http://dx.doi.org/10.4028/www.scientific.net/kem.858.20.

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In this project, experimental work on tensile behaviour of single lap adhesive joints of sisal, glass and hybrid sisal-glass/epoxy composite laminates has been carried out. Composite laminates were fabricated by hand lay-up method using chopped strand mat sisal and glass fibers with epoxy resin matrix. Lab joints of four interface geometries; straight flat, triangular, rectangular and sinusoidal were fabricated. Tensile load-displacement relations were drawn and discussed. Effect of interface geometry and material type on maximum load and strength of the single lap joint was investigated. Failure mechanism of the fractured specimens was discussed. Results show that the glass/epoxy lap joints with semi-circular adhesive interface geometry supported load higher respectively 14.26%, 26.13%, and 30.79% than rectangular, triangular and straight flat interface geometries. Glass/epoxy lap joint with semi-circular interface geometry supported tensile load higher 5.61% and 21.83% than that obtained from hybrid sisal-glass and sisal/ epoxy adhesive joints. While the shear strength was found higher respectively 6.19% and 18.69%. Adhesive failure mode was observed for most of the single lap joints investigated. Mixed failure mode of adhesive and adherend materials was observed on the sisal/epoxy lap joints.

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Nowacki, Jerzy. "Structure and Stresses of Large Size Brazed Joints of Cermets and Steel." Advanced Materials Research 445 (January 2012): 783–88. http://dx.doi.org/10.4028/www.scientific.net/amr.445.783.

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Stresses in brazing joints of different differed in properties were appraised as a result of technological experiments and FEM analysis. Evaluation of microstructure and mechanical properties of large dimensional vacuum brazed joints of Ferro Titanit Nicro 128 sinters and precipitation hardened stainless steel of X5CrNiMoCuNb14-5 using copper as the brazing filler metal. Structure of the joint was described. Shear strength Rt and tensile strength Rm of the joints have been defined. It have been state, that the basic factors decreasing quality of the joint, which can occur during vacuum brazing of the Ferro Titanit Nicro 128 sinter Cu brazing filler metal steel joints are diffusive processes leading to exchange of the cermets and brazing filler metal elements and creation of intermetallic in the joint. It can have an unfavourable influence on ductility and quality of the joint. The effect of joint geometry structure on stresses and deformations as well as on the process of plate cracking has been determined. Results of numerical calculations of three-dimensional models of brazed joints for different sizes of surfaces brazed at a constant width of solder gap are presented. Results of the investigate proved that joints microstructure and mechanical properties depend on filler and parent materials, diffusion process during brazing, leading to exchange of the cermets components and filler metal as well as joint geometry. The thickness of the joints has an essential influence on the values of the local stress and the significant influence on the joint rigidity. In a case of the considered joints the values of the local stress differences have been considerable in dependence of a fixed load manner.

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Wu, X., X. Dou, C. P. Yeh, and K. Waytt. "Solder Joint Formation Simulation and Component Tombstoning Prediction During Reflow." Journal of Electronic Packaging 120, no. 2 (June 1, 1998): 141–44. http://dx.doi.org/10.1115/1.2792601.

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The failure of electrical devices associated with solder joints has become one of the most critical reliability issues for surface-mounted devices. Solder joint reliability performance has been found to be highly dependent on the solder joint configuration, which, in turn, is governed by bond pad size, alloy material, and leadframe structure, as well as solder reflow characteristics. To investigate tombstone effects causing solder joint failure during leadless component reflow process, this work has focused on (1) developing a numerical model for the simulations of the solder joint formation during the reflow process, and (2) determining possibility that a tombstone effect for the leadless component may occur by analyzing the force and torque in the problem. Using this methodology, the tombstone effect associated with different pad geometry configurations and solder paste amount has been analyzed through the application of the public domain software tool Surface Evolver. Simulations show that the tombstoning is very sensitive to pad/component geometry design, solder surface tension, solder paste volume, wetting area, and wetting angle. This model simulation can be used to determine optimal solder paste volume, pad geometry configurations, and solder material for avoiding tombstone effects.

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Vandevelde, Bart, Eric Beyne, Kouchi (G Q. ). Zhang, Jo Caers, Dirk Vandepitte, and Martine Baelmans. "Parameterized Modeling of Thermomechanical Reliability for CSP Assemblies." Journal of Electronic Packaging 125, no. 4 (December 1, 2003): 498–505. http://dx.doi.org/10.1115/1.1604150.

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Finite element modeling is widely used for estimating the solder joint reliability of electronic packages. In this study, the electronic package is a CSP mounted on a printed circuit board (PCB) using an area array of solder joints varying from 5×4 up to 7×7. An empirical model for estimating the reliability of CSP solder joints is derived by correlating the simulated strains to thermal cycling results for 20 different sample configurations. This empirical model translates the inelastic strains calculated by nonlinear three-dimensional (3D) finite element simulations into a reliability estimation (N50% or N100 ppm). By comparing with the results of reliability tests, it can be concluded that this model is accurate and consistent for analyzing the effect of solder joint geometry. Afterwards, parameter sensitivity analysis was conducted by integrating a design of experiment (DOE) analysis with the reliable solder fatigue prediction models, following the method of simulation-based optimization. Several parameters are analyzed: the PCB parameters (elastic modulus, coefficient of thermal expansion, thickness), the chip dimensions (area array configuration), and the parameters defining the solder joint geometry (substrate and chip pad diameter, solder volume). The first study analyzes how the solder joint geometry influences the CSP reliability. A second study is a tolerance analysis for six parameters. These parameters can have a tolerance (=accuracy) of their nominal value, and it is shown that these small tolerances can have a significant influence on the solder joint reliability.

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Kelly, P. A., D. A. Hills, and D. Nowell. "The design of joints between elastically dissimilar components (with special reference to ceramic/metal joints)." Journal of Strain Analysis for Engineering Design 27, no. 1 (January 1, 1992): 15–20. http://dx.doi.org/10.1243/03093247v271015.

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Three kinds of joints between bonded, elastically dissimilar components loaded in tension are studied. Each involves a plane interface, but with various changes in geometry at the outside edge of the bond. These geometric features are intended to avoid singularities which would otherwise arise there, and should therefore inhibit peeling of the joint and hence the formation of a crack. Explicit equations describing the necessary conditions in terms of the elastic parameters of the bonded components are given.

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Caputo, Francesco, Giuseppe Lamanna, and Alessandro Soprano. "About the Effects of Residual Stress States Coming from Manufacturing Processes on the Behaviour of Riveted Joints." Key Engineering Materials 385-387 (July 2008): 25–28. http://dx.doi.org/10.4028/www.scientific.net/kem.385-387.25.

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A very large number of variables affect the response of bolted or riveted joints typically used in aerospace applications: geometry of the joint, characteristics of the sheets, friction between sheets, geometry of head and kind of fastener, amplitude of clearance before assembly, mounting axial load, pressure effects after manufacture. It must be also recalled that these parameters influence the many failure modes existing for such joints, among which a relevant importance is attributed to bearing. The present paper deals with the study of the influence of assembly parameters on the joint operational behaviour and in particular with the analysis, performed through numerical simulations, of the influence of the residual stress-strain state coming from the riveting operation on the bearing resistance of an aluminium alloy joint. This work has been developed within the FP6 research project called MUSCA (Non linear static multiscale analysis of large aero-structures).

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Xiong, Tao, Liping Chen, Jianwan Ding, Yizhong Wu, and Wenjie Hou. "Recognition of Kinematic Joints of 3D Assembly Models Based on Reciprocal Screw Theory." Mathematical Problems in Engineering 2016 (2016): 1–13. http://dx.doi.org/10.1155/2016/1761968.

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Reciprocal screw theory is used to recognize the kinematic joints of assemblies restricted by arbitrary combinations of geometry constraints. Kinematic analysis is common for reaching a satisfactory design. If a machine is large and the incidence of redesign frequent is high, then it becomes imperative to have fast analysis-redesign-reanalysis cycles. This work addresses this problem by providing recognition technology for converting a 3D assembly model into a kinematic joint model, which is represented by a graph of parts with kinematic joints among them. The three basic components of the geometric constraints are described in terms of wrench, and it is thus easy to model each common assembly constraint. At the same time, several different types of kinematic joints in practice are presented in terms of twist. For the reciprocal product of a twist and wrench, which is equal to zero, the geometry constraints can be converted into the corresponding kinematic joints as a result. To eliminate completely the redundant components of different geometry constraints that act upon the same part, the specific operation of a matrix space is applied. This ability is useful in supporting the kinematic design of properly constrained assemblies in CAD systems.

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Danielewski, Hubert, Andrzej Skrzypczyk, Szymon Tofil, Grzegorz Witkowski, and Sławomir Rutkowski. "Numerical Simulation of Laser Welding Dissimilar Low Carbon and Austenitic Steel Joint." Open Engineering 10, no. 1 (June 5, 2020): 491–98. http://dx.doi.org/10.1515/eng-2020-0045.

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AbstractNumerical simulation of laser welding dissimilar joint was presented. Results of butt joint for low carbon and austenitic steels are studied. Numerical calculations based on thermo-mechanical method and phase transformation were used for estimating weld dimensions and joint properties. Unconventional welding method where focused photons beam are used as a heat source were presented. Problems with welding of dissimilar joints, where different composition and thermo physical material properties affect on this phenomena complexity are solved using numerical methods and laser welding technology. Simulation of low carbon and stainless steel joints using SimufactWelding software are presented. Model of heat source within geometry and parameters was programmed. Laser beam welding simulation was performed for estimating parameters for complete joints penetration. Programming welding boundary condition and heat source geometry welding parameters with output power and welding speed rate was estimated. Materials used in simulation process and experimental welding was low carbon construction S235JR and stainless 316L steels in sheets form. Joint properties such as fusion zone and heat affected zones dimensions and stress-strain distribution were calculated. Estimation of complete joint characteristics was obtained using thermo-mechanical simulation method and Marc solver engine.. Experimental trial butt joint welding were performed based on estimated parameters. Welding process was performed using 6kW CO2 laser system. Based on numerical simulation, microstructure analysis, hardness distribution and chemical distribution of fusion zone, properties of obtained joint was studied. Model for simulation of dissimilar laser welding joint was obtained, and properties of obtained joint based on simulation and experiment was studied.

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Shenoi, R. A., P. J. C. L. Read, and C. L. Jackson. "Influence of Joint Geometry and Load Regimes on Sandwich Tee Joint Behaviour." Journal of Reinforced Plastics and Composites 17, no. 8 (May 1998): 725–40. http://dx.doi.org/10.1177/073168449801700804.

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Becker, Joanne, Emmanuel Mermoz, and Jean-Marc Linares. "Determination of biological joint reaction forces from in-vivo experiments using a hybrid combination of biomechanical and mechanical engineering software." Mechanics & Industry 21, no. 6 (2020): 623. http://dx.doi.org/10.1051/meca/2020088.

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In biomechanical field, several studies used OpenSim software to compute the joint reaction forces from kinematics and ground reaction forces measurements. The bio-inspired joints design and their manufacturing need the usage of mechanical modeling and simulation software tools. This paper proposes a new hybrid methodology to determine biological joint reaction forces from in vivo measurements using both biomechanical and mechanical engineering softwares. The methodology has been applied to the horse forelimb joints. The computed joint reaction forces results would be compared to the results obtained with OpenSim in a previous study. This new hybrid model used a combination of measurements (bone geometry, kinematics, ground reaction forces…) and also OpenSim results (muscular and ligament forces). The comparison between the two models showed values with an average difference of 8% at trotting and 16% at jumping. These differences can be associated with the differences between the modelling strategies. Despite these differences, the mechanical modeling method allows the computation of advanced simulations to handle contact conditions in joints. In future, the proposed mechanical engineering methodology could open the door to define a biological digital twin of a quadruped limb including the real geometry modelling of the joint.

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Eshteyah, M., Meftah Hrairi, M. S. Dawood, and A. K. M. Mohiuddin. "Finite Element Modeling of Clinching Process for Joining Dissimilar Materials." Advanced Materials Research 1115 (July 2015): 109–12. http://dx.doi.org/10.4028/www.scientific.net/amr.1115.109.

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Clinching is one of the important new joining techniques, in which two plate metal parts are locally plastically deformed by mechanical interlock. Clinching is a mechanical joining method by using simple tools that consist of a punch, a die, and a blank-holder. The shapes of these tools are the most important parameters that control the final geometry of the clinch joints which in turn strongly affect the strength and quality of the final joint. In this study, finite element simulations are carried out to investigate some of the difficulties regarding the optimization of the process parameters, and major expected geometric parameters that will influence the strength, joinability, and the quality of the joint.

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Foroutan, M., M. E. Aalami-Aleagha, and S. Pirmoradi. "Investigation of Joint Groove Geometry Effect on the Residual Stresses in Circumferentially Butt-Welded Steel Pipes by the FEM Simulation." Advanced Materials Research 264-265 (June 2011): 229–34. http://dx.doi.org/10.4028/www.scientific.net/amr.264-265.229.

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In this paper effect of joint groove geometry on the residual stresses in circumferentially butt-welded still pipes is investigated by the finite element simulation. The elements birth and death technique is used for modeling of filling metal and joint groove geometry. The electrode heat power is modeled by a moving heat source which has a Gaussian distribution on a spherical domain. By using a transient region, elements near the welding zone are refined in a good manner. For validation of the proposed model, results obtained from model are compared with experimental data. Then three different joint geometry; V-joint, U-joint and X-joint are studied by the presented model.

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Rogers, Boyd, and Chris Scanlan. "Improving WLCSP Reliability Through Solder Joint Geometry Optimization." International Symposium on Microelectronics 2013, no. 1 (January 1, 2013): 000546–50. http://dx.doi.org/10.4071/isom-2013-wa45.

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The effects of solder joint geometry on wafer-level chip-scale package reliability have been studied both through simulations and board level reliability testing. In reliability tests on a 3.9×3.9mm2 die, an enhancement of nearly 2× in thermal cycling reliability was achieved by optimizing the solder joint and under-bump pad stack. In particular, undersizing the printed circuit board pad to produce a more spherical solder joint and reducing the polymer via size under the bump appear to be very important for improving thermal cycling results. Data collected here shows that joint geometry changes can be implemented without compromising drop performance. Methods learned were applied to the qualification of a 6.0×6.0mm2 die, a large platform for WLCSP applications.

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Šobra, Karel, and Petr Fajman. "Utilization of Splice Skew Joint with Key on Reconstruction of Historical Trusses." Advanced Materials Research 688 (May 2013): 207–12. http://dx.doi.org/10.4028/www.scientific.net/amr.688.207.

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Currently, for reconstruction of historical trusses traditional carpentry joints are used. For many years these joints are constructed in the same way. Unfortunately, the mechanical behaviour of these joints and influence of their parts and geometry of joints to the joint stiffness are not well known. To improve these joints, it is necessary to know their behaviour. This paper describes a study recently completed on the vertical splice skew joint with a key. Experimental tests were performed and compared to the numerical results of three-dimensional finite element model created using ATENA 3D.

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ERTELT, THOMAS, HANS JUERGEN ERTELT, and REINHARD BLICKHAN. "THE GEOMETRY-CRITICAL FUNCTIONAL DEPENDENCE OF M. GASTROCNEMIUS." International Journal of Applied Mechanics 03, no. 01 (March 2011): 85–98. http://dx.doi.org/10.1142/s1758825111000889.

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The change in length of a muscle usually leads to a change in segment position. If a muscle is shortened the joint is being flexed. However bi-articular muscles are able to bend a joint as well as to stretch it by its contraction because of varied geometrical conditions. This phenomenon has already been analyzed in different surveys on M. biceps femoris. Until today such a consideration cannot be found for M. gastrocnemius, which is a bi-articular muscle, too. The weight- and speed-dependent activities of this muscle during fast and slow hopping, and also during running and walking, suggest that a movement-relevant function exists. This behavior pattern was the reason for a closer look on the actions of M. gastrocnemius from a geometrical point of view. The results clearly show a knee angle-dependent function. Moreover, a so-called critical angle area of the knee joint, from which the shortening of M. gastrocnemius leads from joint flexion to joint stretching, can be specified for the first time. At this, the position of the ankle joint seems to have little influence on the function of M. gastrocnemius.

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Stessin, M. I., and A. B. Tchernev. "Geometry of joint spectra and decomposable operator tuples." Journal of Operator Theory 82, no. 1 (July 5, 2019): 79–113. http://dx.doi.org/10.7900/jot.2018feb21.2227.

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Jobe, Christopher M., and Joseph P. Lannotti. "Limits imposed on glenohumeral motion by joint geometry." Journal of Shoulder and Elbow Surgery 4, no. 4 (July 1995): 281–85. http://dx.doi.org/10.1016/s1058-2746(05)80021-7.

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Pratt, John D., and Gerard Pardoen. "Influence of Head Geometry on Bolted Joint Behavior." Journal of Aerospace Engineering 15, no. 4 (October 2002): 136–53. http://dx.doi.org/10.1061/(asce)0893-1321(2002)15:4(136).

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Journal articles on the topic 'Joint geometry'

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