Effects of the joint surface considering asperity interaction on the bolted joint performance in the bolt tightening process

2021 ◽  
pp. 107408
Author(s):  
Kai Jiang ◽  
Zhifeng Liu ◽  
Congbin Yang ◽  
Caixia Zhang ◽  
Yang Tian ◽  
...  
Keyword(s):  
Joint Surface ◽  
Bolted Joint ◽  
Joint Performance

scholarly journals Dynamic modeling method of the bolted joint with uneven distribution of joint surface pressure

AIP Advances ◽  
2018 ◽  
Vol 8 (3) ◽  
pp. 035116 ◽  
Author(s):  
Shichao Li ◽  
Hongli Gao ◽  
Qi Liu ◽  
Bokai Liu
Keyword(s):  
Dynamic Modeling ◽  
Surface Pressure ◽  
Modeling Method ◽  
Uneven Distribution ◽  
Joint Surface ◽  
Bolted Joint

scholarly journals Shear Strength of Flat Joint considering Influencing Area of Bolts

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Hang Lin ◽  
Penghui Sun ◽  
Yifan Chen
Keyword(s):  
Shear Strength ◽  
Jointed Rock ◽  
Calculation Model ◽  
Bolted Joints ◽  
Rock Joints ◽  
Joint Surface ◽  
Influence Coefficient ◽  
Test Results ◽  
Bolted Joint ◽  
Joint Shear Strength

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.

Experimental Study of the Bolted Joint Surface Contact Angle

2013 ◽  
Vol 765-767 ◽  
pp. 181-184
Author(s):  
Ai Ping Zhang ◽  
Dong Mei Zhang ◽  
Zhi Feng Liu
Keyword(s):  
Experimental Study ◽  
Contact Angle ◽  
Experimental Research ◽  
Research Method ◽  
Structure Design ◽  
Joint Surface ◽  
Bolted Joint ◽  
Mechanical Structure ◽  
Surface Contact Angle ◽  
Effective Angle

We will study the effective value of the angle which affect on the bolted joint surface by the experimental research method. It gets the effective angle under different conditions in the experiment by the way of researching the joint surface stiffness which changing during the joint surface area changing in the paper. This results provide valid reference for the mechanical structure design which with the bolted joint surface, so as to achieving the purpose of more efficiency during the mechanical structure design.

Inverse Solution for Bolt Preload Using Surface Deformation

2017 ◽  
Vol 139 (4) ◽  
Author(s):  
A. Zaki ◽  
S. A. Nassar ◽  
S. Kruk ◽  
M. Shillor
Keyword(s):  
Inverse Problem ◽  
Surface Deformation ◽  
Control Method ◽  
Plane Surface ◽  
Joint Surface ◽  
Problem Solution ◽  
Bolted Joint ◽  
Element Analysis ◽  
Out Of Plane ◽  
Axisymmetric Elasticity

In this paper, an inverse biharmonic axisymmetric elasticity problem is solved by invoking measured out-of-plane surface deformation values at discrete locations around a preloaded bolt head, in order to calculate the underhead contact stress and joint clamp load that would have caused that out-of-plane surface deformation. Solution of this type of inverse problem promises to improve the automation process of bolted joint system assembly, especially in critical and safety-related applications. For example, a real-time optically measured joint surface deformation can be utilized for automating process control of bolted joint assembly in a reliable fashion. This would be a significant reliability improvement as compared to the commonly used method in mass production using torque-only control method in which there is wide scatter in the torque–tension correlation due to the normal scatter in frictional variables. Finite element analysis (FEA) method is used to validate the inverse problem solution provided in this paper.

Inverse Solution for Bolt Preload Using Joint Surface Deformation

2013 ◽  
Author(s):  
Amro M. Zaki ◽  
Sayed A. Nassar ◽  
Meyer Shillor ◽  
Serge Kruk
Keyword(s):  
Inverse Problem ◽  
Surface Deformation ◽  
Control Method ◽  
Plane Surface ◽  
Joint Surface ◽  
Problem Solution ◽  
Bolted Joint ◽  
Element Analysis ◽  
Out Of Plane ◽  
Axisymmetric Elasticity

In this paper, an inverse bi-harmonic axisymmetric elasticity problem is solved by invoking measured out-of-plane surface deformation values at discrete locations around a preloaded bolt head, in order to calculate the under head contact stress and joint clamp load that would have caused that out-of-plane surface deformation. Solution of this type of inverse problem promises to improve the automation process of bolted joint system assembly, especially in critical and safety related applications. For example, a real-time optically measured joint surface deformation can be utilized for automating process control of bolted joint assembly in a reliable fashion. This would be a significant reliability improvement as compared to the commonly used method in mass production using torque-only control method in which there is wide scatter in the torque-tension correlation due to the normal scatter in frictional variables. Finite Element Analysis (FEA) method is used to validate the inverse problem solution provided in this paper.

Representation of bolted joints in a structure using finite element modelling and model updating

2020 ◽  
Vol 14 (3) ◽  
pp. 7141-7151 ◽  
Author(s):  
R. Omar ◽  
M. N. Abdul Rani ◽  
M. A. Yunus
Keyword(s):  
Finite Element ◽  
Dynamic Behaviour ◽  
Model Updating ◽  
Complex Structure ◽  
Bolted Joints ◽  
Model Parameters ◽  
Fe Model ◽  
Bolted Joint ◽  
Fe Modelling ◽  
Joint Structure

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.

Leakage characteristics of flanged pipe joints

1977 ◽  
Vol 12 (1) ◽  
pp. 29-36 ◽  
Author(s):  
H Fessler ◽  
D A Perry
Keyword(s):  
Surface Finish ◽  
Joint Surface ◽  
Clamping Force ◽  
Face Surface ◽  
Joint Efficiency ◽  
Wide Range ◽  
Pipe Joints ◽  
Surface Profiles ◽  
Leakage Characteristics ◽  
Gasket Material

Standard flanges for five widely differing pressure ratings, having a wide range of different joint surface profiles, were sealed by flat rubber or asbestos gaskets. Different initial bolt tensions were applied and the variation of clamping force with internal pressure was measured up to leakage of the joint. The joint efficiency, defined as: (end thrust due to leakage pressure on bore area of pipe)/(total initial bolting force), is not affected by variations in joint-face surface finish if machining grooves across the joint surface are avoided. Minimum values of joint efficiency are given. The effects of gasket material, width and thickness and number of bolts on joint efficiency are considered.

scholarly journals Anatomy of the Intermetatarsal Facets of the Fourth and Fifth Metatarsals

2021 ◽  
Vol 6 (1) ◽  
pp. 247301142097570
Author(s):  
Mossub Qatu ◽  
George Borrelli ◽  
Christopher Traynor ◽  
Joseph Weistroffer ◽  
James Jastifer
Keyword(s):  
Articular Cartilage ◽  
Digital Imaging ◽  
Articular Surface ◽  
Implant Design ◽  
Joint Surface ◽  
Fracture Classification ◽  
Articular Damage ◽  
Metatarsal Fracture ◽  
Metatarsal Fractures ◽  
The Mean

Background: The intermetatarsal joint between the fourth and fifth metatarsals (4-5 IM) is important in defining fifth metatarsal fractures. The purpose of the current study was to quantify this joint in order to determine the mean cartilage area, the percentage of the articulation that is cartilage, and to give the clinician data to help understand the joint anatomy as it relates to fifth metatarsal fracture classification. Methods: Twenty cadaver 4-5 IM joints were dissected. Digital images were taken and the articular cartilage was quantified by calibrated digital imaging software. Results: For the lateral fourth proximal intermetatarsal articulation, the mean area of articulation was 188 ± 49 mm2, with 49% of the area composed of articular cartilage. The shape of the articular cartilage had 3 variations: triangular, oval, and square. A triangular variant was the most common (80%, 16 of 20 specimens). For the medial fifth proximal intermetatarsal articulation, the mean area of articulation was 143 ± 30 mm2, with 48% of the joint surface being composed of articular cartilage. The shape of the articular surface was oval or triangular. An oval variant was the most common (75%, 15 of 20 specimens). Conclusion: This study supports the notion that the 4-5 IM joint is not completely articular and has both fibrous and cartilaginous components. Clinical Relevance: The clinical significance of this study is that it quantifies the articular surface area and shape. This information may be useful in understanding fifth metatarsal fracture extension into the articular surface and to inform implant design and also help guide surgeons intraoperatively in order to minimize articular damage.

scholarly journals Study on the Bending and Joint Performances of Reinforced Concrete Beams Using High-Strength Rebars

2021 ◽  
Vol 13 (6) ◽  
pp. 3482
Author(s):  
Seoungho Cho ◽  
Myungkwan Lim ◽  
Changhee Lee
Keyword(s):  
Yield Strength ◽  
High Strength ◽  
Reinforced Concrete Beams ◽  
High Yield ◽  
Performance Tests ◽  
Reinforcing Bars ◽  
Joint Performance ◽  
Lap Splice ◽  
Reinforcing Bar ◽  
Nominal Strength

High-strength reinforcing bars have high yield strengths. It is possible to reduce the number of reinforcing bars placed in a building. Accordingly, as the amount of reinforcement decreases, the spacing of reinforcing bars increases, workability improves, and the construction period shortens. To evaluate the structural performance of high-strength reinforcing bars and the joint performance of high-strength threaded reinforcing bars, flexural performance tests were performed in this study on 12 beam members with the compressive strength of concrete, the yield strength of the tensile reinforcing bars, and the tensile reinforcing bar ratio as variables. The yield strengths of the tensile reinforcement and joint methods were used as variables, and joint performance tests were performed for six beam members. Based on this study, the foundation for using high-strength reinforcing bars with a design standard yield strength equal to 600 MPa was established. Accordingly, mechanical joints of high-strength threaded reinforcing bars (600 and 670 MPa) can be used. All six specimens were destroyed under more than the expected nominal strength. Lap splice caused brittle fractures because it was not reinforced in stirrup. Increases of 21% to 47% in the loads of specimens using a coupler and a lock nut were observed. Shape yield represents destruction—a section must ensure sufficient ductility after yielding. Therefore, a coupler and lock nut are effective.

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