Types Of Joints Research Articles

Influence of joint types on rigidity of Chebyshev elastic gridshells: A parametric analysis

Elastic gridshells (EGS) have many applications in the field of architecture. Built according to Chebyshev net geometry, the Chebyshev EGS (CGES) is a famous kind of EGS; since an arbitrary three-dimensional CEGS can be transformed into a planar state without any stretching strain. Due to its tremendous potential application in novelly deployed structures, the rigidity of CEGS is an important mechanical property to be investigated.In this study, using the analytical and finite element methods, the influence of joint types and gridshell parameters on the rigidity of CEGS subjected to point loads is studied in detail. The joint types are classified as pin joints, semi-rigidity joints, and rigid joints. A robust relation between rigidity and gridshell parameters is proposed, including Young's modulus, rod diameter, size of CEGS, joint stiffness, and rod numbers. Further, the above relation is nondimensionalized. The dimensionless rigidity is only related to the two dimensionless parameters, which are dimensionless joint stiffness and rod number. The rigidities of CEGS on four types of surfaces are calculated to verify the above relation, and satisfactory agreement is obtained. Therefore, the proposed relationship of rigidity is confirmed to be accurate and efficient for a wide range of parameters.

Effects of Myofascial Release Techniques on Joint Range of Motion of Athletes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Although myofascial release techniques (MRTs) are commonly used to improve athletes' range of motion (ROM), the effectiveness of MRTs may vary depending on the specific method performed. This systematic review and meta-analysis aimed to evaluate the effects of MRTs on the ROM performance of athletes. (2) Methods: The electronic databases of Cochrane Library, PubMed, Scopus, and Web of Science were searched to identify relevant articles published up to June 2023. This study utilized the PRISMA guidelines, and four databases were searched. The methodological quality of the studies was assessed using the PEDro scale, and the certainty of evidence was reported using the GRADE scale. The overall effect size was calculated using the robust variance estimator, and subgroup analyses were conducted using the Hotelling Zhang test. (3) Ten studies met the inclusion criteria. The overall effect size results indicated that the myofascial release intervention had a moderate effect on ROM performance in athletes when compared to the active or passive control groups. (4) Conclusions: Alternative MRTs, such as myofascial trigger point therapy, can further improve the ROM performance of athletes. Gender, duration of intervention, and joint type may have a moderating effect on the effectiveness of MRTs.

Gait Analysis of Knee Joint Walking Based on Image Processing.

With the in-depth development of assistive treatment devices, the application of artificial knee joints in the rehabilitation of amputees is becoming increasingly mature. The length of residual limbs and muscle strength of patients have individual differences, and the current artificial knee joint lacks certain adaptability in the personalized rehabilitation of patients. In order to deeply analyze the impact of different types of artificial knee joints on the walking function of unilateral thigh amputees, improve the performance of artificial knee joints, and enhance the rehabilitation effect of patients, this article combines image processing technology to conduct in-depth research on the walking gait analysis of different artificial knee joints of unilateral thigh amputees. This article divides patients into two groups: the experimental group consists of patients with single leg amputation, and the control group consists of patients with different prostheses. An image processing system is constructed using universal video and computer hardware, and relevant technologies are used to recognize and track landmarks; Furthermore, image processing technology was used to analyze the gait of different groups of patients. Finally, by analyzing the different psychological reactions of amputees, corresponding treatment plans were developed. Different prostheses worn by amputees have brought varying degrees of convenience to life to a certain extent. The walking stability of wearing hydraulic single axis prosthetic joints is only 79%, and the gait elegance is relatively low. The walking stability of wearing intelligent artificial joints is as high as 96%. Elegant gait is basically in good condition. Image processing technology helps doctors and rehabilitation practitioners better understand the gait characteristics and rehabilitation progress of patients wearing different artificial knee joints, providing objective basis for personalized rehabilitation of patients.

New Technique of Glenohumeral Joint Dissection

Objectives: Glenohumeral is a ball and socket type of synovial joint which permits a wide range of movement. During the typical shoulder joint dissection, we are unable to see the intracapsular view of shoulder joint. Methods: A dissection technique that was performed in Sharir Rachana Dept. of NIA, Jaipur, which exposes the glenohumeral joint's internal capsule, the glenoid labrum, the proximal insertion of the long head of the biceps tendon, and the surfaces of the joint while protecting the posterior aspect of the capsule and the surrounding muscles and tendons that support the joint. Results: This new dissection method allowed the preservation of glenohumeral joint structures and provides a better understanding of its intracapsular view and related structures. Conclusion: The glenohumeral joint can be dissected using this new technique, by which we can prevent the damage to the structures that surround it and enabling visualization of its intracapsular view.

Seismic performance of precast steel fiber reinforced lightweight aggregate concrete shear walls assembled with a socket horizontal joint

In the context of constructing a precast shear wall structure, the connection of precast units plays a crucial role in ensuring structural safety and facilitating efficient construction, while the use of conventional concrete for heavy precast units leads to low lifting efficiency. It promotes the study of this paper, which proposed a novel type of socket horizontal joint for precast shear walls made of steel fiber reinforced lightweight aggregate concrete (SFRLAC). Three specimens were tested using the low-cyclic loading test: two reinforced SFRLAC shear walls assembled with a socket horizontal joint and a cast-in-place reinforced SFRLAC shear wall as a reference. The failure patterns and process of the shear walls were observed, while the load-displacement curves were obtained. Additionally, finite element (FE) numerical models were built to conduct parametric analysis on different influencing factors. The bearing capacity, energy dissipation capability, deformation ability, and stiffness degradation of the shear walls were studied. Results indicate that when the precast shear walls failed in bending-shear, the socket horizontal joint remained intact. The three shear walls exhibited fewer differences in seismic behaviors with relatively full hysteretic curves. The seismic mechanisms of the shear walls assembled with a socket horizontal joint are elucidated by analyzing the numerical distribution of stress in both SFRLAC and steel bars at different stress levels. Meanwhile, the study assesses the mechanical properties of precast shear walls by analyzing the impact of the shear to span ratio and the axial compression ratio.

Three-dimensional mechanical characteristics analysis of double-shoulder tool joint under complex loads

Taking a new type of special threaded drill pipe joint as the research object, a 3D nonlinear finite element model of the double-shoulder tool joint (DSJ) including the engage and retract groove structure is established by considering the factors of structural asymmetry and contact of each engaging surface. ABAQUS/Explicit finite element method (FEM) is used to study the stress and contact pressure distribution characteristics of the critical structure of DSJ under make-up torque and axial tension. The accuracy of the finite element model was verified by combining with a full-scale physical test, and the connection strength and sealing performance of DSJ are evaluated. The results show that the stress concentration occurs at the key structure of DSJ under the make-up torque. The geometry size and structural discontinuity at the transition fillet of the double-shoulder structure have a significant effect on the stress and contact pressure distribution on the shoulder. Under axial tension, the stress level and stress concentration area of the whole joint and the key structure change, especially in the thread section. The sealing performance on the shoulder decreases significant, while that of the thread section increases slightly. The test results are consistent with the finite element analysis findings, and this joint shows good mechanical properties, which can meet the design requirements of drilling tool manufacturers and provide data support for its optimal design and application.

A6N01S-T5 physical characterization of laser-MIG hybrid welding of aluminum alloys

A 3 mm thick A6N01S-T5 aluminum alloy profile typical joint structure is used to carry out a laser-MIG hybrid welding test. The hybrid welding process parameters are optimized. The laser-MIG hybrid welding engineering adaptability is studied. The results show that the weld is well-formed and free of porosity defects under the optimum process parameters. The center of the weld is a dendritic cast organization. The region near the fusion line weld is a columnar crystal organization. The fusion zone is narrow, but there is a slight coarsening of the grain in the heat-affected zone. The hardness of the weld zone is lower than that of the parent material. The minimum hardness is located in the heat-affected zone near the fusion line. The average tensile strength of the joint under the best process parameters is 204.6 MPa, reaching 83.5% of the parent material. The fracture occurred near the fusion line, and the fracture shape showed typical plastic fracture characteristics. The bending performance of the joint was good. The optimal process parameters were universal when the pair gap was less than 1.0 mm, and the weld formation and tensile strength of the joint were good. When the pair gap increased to 1.5 mm, the optimized process parameters of the weld formation and tensile strength of the joint were still good. The results show that laser-MIG hybrid welding has good welding feasibility and engineering adaptability for typical joints in aluminum alloy bodies of high-speed trains.

Prediction of peel strength of sandwich sheets made of aluminium alloys fabricated by friction stir spot welding based hybrid process using cohesive zone modeling and finite element simulations

The present work examines the fabrication and numerical modelling of honeycomb core sandwich sheets utilizing Friction Stir Spot Welding (FSSW) techniques as prospective substitutes for adhesive-bonded structures. Here, the sandwich sheet contains AA5052-H32 skins and AA3003 honeycomb core. Two strategies, FSSW with disc insert (FSSW_D) and FSSW with disc insert and adhesive bonding (FSSW_D_AB), were evaluated against traditional adhesive-bonded sandwiches using peel test performance and finite element (FE) simulation with cohesive zone modelling (CZM). In the CZM, a homogenized core with an equivalent cohesive layer was substituted for the honeycomb core and cohesive layer. The utilization of FSSW_D and FSSW_D_AB methods resulted in substantial improvements in maximum load capacity, with enhancements in the hybrid sandwich specimen ranging from 254 % to 399 % compared to adhesive-bonded connections. The maximum load of hybrid joints (FSSW_D_AB) was 15 %–23 % higher than that of ordinary spot-welded joints (FSSW_D). An approach to model the hybrid sandwich specimen using both the homogenized core and equivalent cohesive zone model accurately was proposed. FE analysis, including peel tests of adhesive-bonded, spot-welded, and hybrid joints, was performed, and the numerical predictions agreed satisfactorily with the experimental values for all the joint types.

Flexible pavement longitudinal joint quality evaluation using non-destructive testing

Longitudinal joint construction quality is critical to the life of flexible pavements. Maintaining deteriorated longitudinal joints has become a challenge for many highway agencies. Improving the joint's quality through better compaction during construction can help achieve flexible pavements with longer service lives and less maintenance. Current quality control (QC) and quality assurance (QA) plans provide limited coverage. Consequently, the risk of missing areas with poor joint compaction is significant. A density profiling system (DPS) is a non-destructive alternative to conventional destructive evaluation methods. It can provide quick and continuous real-time coverage of the compaction during construction in dielectrics. The paper presents several case studies comparing various types of longitudinal joints and demonstrating the use of DPS to evaluate the joint's compaction quality. The paper shows that dielectric measurements can provide valuable insight into the ability of various construction techniques to achieve adequate levels of compaction at the longitudinal joint. The paper proposes a dielectric-based longitudinal joint quality index (LJQI) to evaluate the relative compaction of the joint during construction. It also shows that adopting DPS for assessing the compaction of longitudinal joints can minimize the risk of agencies accepting poorly constructed joints, identify locations of poor quality during construction, and achieve better-performing flexible pavements.

Development of laser-arc hybrid welding process of butt joint for bogie pipe crossbeam components

High-speed railway vehicle bogies are the main load-bearing components, which are welded together from steel plates and tubes. Butt joint and T-joint are the main types and the joint thickness is between 8–20mm. The stability of laser-arc hybrid welding (LAHW) process correlated strongly with keyhole behaviour. In this paper, the common quality defects in full penetration root pass by LAHW were analysed. Controlling the root gap is adopted to stabilize the keyhole, to improve the stability of weld quality. A novel type of butt joint with micro structure based on Y-shaped grooves has been designed, to meet both the requirement of controlling root gap and industrial large-scale batch production. Two new structure parameters, 2 mm of the remaining blunt edge thickness and 0.3 mm of the half width of root opening, were proved by the flat plates welding test. Finally, the joint with micro structure and the root pass welding parameters were transferred to the welding process of tube crossbeam components. The LAHW process verification was completed, and the test results showed the process meets the requirements of ISO 15614.

Bio-based hybrid planar truss: Experimental testing, FE modeling and Bayesian model updating

This paper examines the cyclic behavior of a bio-based truss structure with slotted steel plate bolted connections through a comprehensive approach involving experimental testing, FE modeling, and Bayesian model updating. Experimental tests were performed on both connection and truss levels to determine the cyclic behavior. For the joint level, a total of four distinct joint configurations were tested to determine their axial hysteretic behavior. For the truss level, cyclic tests were carried out on four hybrid planar trusses composed of the four types of truss joints. To define the axial hysteretic behavior of the joints, a robust numerical model is first defined accounting for hysteretic behavior in OpenSees. The proposed model can capture sliding, contact, pinching, strength degradation, and failure behavior. A model reduction via parameter sensitivity analysis is first performed. A Bayesian parameter identification based on Sequential Monte Carlo method was performed based on cyclic truss joints tests. A model of the hybrid truss was developed in OpenSees by integrating the joints and elastic truss elements. The developed model underwent validation using various experimental parameters, including the hysteresis curve, relative displacement at joints, and strain values at each chord. To correct the errors and the bias, a Bayesian model updating framework based on the Sequential Monte Carlo method is proposed herein to deal with model uncertainty. The proposed framework enables the acquisition of highly precise predictions by incorporating global and/or local responses while appropriately accounting for model uncertainties.

Effects of filler materials on the microstructural characteristics and mechanical properties of laser-welded lap joints of TZM alloys

The poor weldability of molybdenum (Mo) alloys has always been the main problem that impedes their application as large-sized structural components. Two types of laser-welded lap joints, namely LW-Ti and LW-Nb joints, were prepared using titanium (Ti) and niobium (Nb) as filler materials to investigate the alterations in microstructures and mechanical properties of TZM (Mo-0.5Ti-0.08Zr-0.02C) alloy joints. The results indicate that both Ti and Nb have excellent metallurgical compatibility with Mo, resulting in well-formed joints. Due to solid-solution strengthening, the microhardness of the fusion zone (FZ) significantly increases from 269.9 HV to 397.1 HV for LW-Ti joints and reaches 389.6 HV for LW-Nb joints. Furthermore, the shear strength of LW-Ti joints is approximately 2.05 times that of LW-Nb joints, measuring at 110.97 MPa. Fractures in LW-Ti joints primarily occur at the base metal (BM) and display lamellar ductile fracture characteristics, while fractures in LW-Nb joints mainly occur at the FZ and exhibit coarse brittle intergranular fractures. The mechanical properties of LW-Nb joints are compromised due to the larger maximum pore diameter (300 μm) in the FZ compared to LW-Ti joints (50 μm), which can be attributed to the higher viscosity of liquid niobium. Additionally, the average grain size in the FZ of LW-Nb joints (86.37 μm) is larger than that in LW-Ti joints (53.28 μm). The reduction in grain size observed in LW-Ti joints also increases the grain boundary area, decreases oxygen concentration along the grain boundaries, and enhances binding strength at Mo grain boundaries. Given Ti's stronger affinity for oxygen compared to Mo, the abundant formation of second-phase TiO2 particles within LW-Ti joints hinders the specific formation of MoO2 along grain boundaries. Consequently, the proposed welding technology was employed to weld a large-scale cylinder-flange component made from Mo alloy, which is expected to greatly facilitate the widespread utilization of welded structures made from Mo alloys.

Investigation of contact behavior on a model of the dual-mobility artificial hip joint for Asians in different inner liner thicknesses.

The four components that make up the current dual-mobility artificial hip joint design are the femoral head, the inner liner, the outer liner as a metal cover to prevent wear, and the acetabular cup. The acetabular cup and the outer liner were constructed of 316L stainless steel. At the same time, the inner liner was made of ultra-high-molecular-weight polyethylene (UHMWPE). As this new dual-mobility artificial hip joint has not been researched extensively, more tribological research is needed to predict wear. The thickness of the inner liner is a significant component to consider when calculating the contact pressure. To make use of finite element analysis to gain a better understanding of the contact behavior in various inner liner thicknesses on a new model of a dual-mobility artificial hip joint, with the ultimate objective of determining the inner liner thickness that was most suitable for this particular type of dual-mobility artificial hip joint. In this study, the size of the femoral head was compared between two diameters (28 mm and 36 mm) and eight inner liner thicknesses ranging from 5 mm to 12 mm. Using the finite element method, the contact parameters, including the maximum contact pressure and contact area, have been evaluated in light of the Hertzian contact theory. The simulation was performed statically with dissipated energy and asymmetric behavior. The types of interaction were surface-to-surface contact and normal contact behavior. The maximum contact pressures in the inner liner (UHMWPE) at a head diameter of 28 mm and 36 mm are between 3.7-13.5 MPa and 2.7-10.4 MPa, respectively. The maximum von Mises of the inner liner, outer liner, and acetabular cup are 2.4-11.4 MPa, 15.7-44.3 MPa, and 3.7-12.6 MPa, respectively, for 28 mm head. Then the maximum von Mises stresses of the 36 mm head are 1.9-8.9 MPa for the inner liner, 9.9-32.8 MPa for the outer liner, and 2.6-9.9 MPa for the acetabular cup. A head with a diameter of 28 mm should have an inner liner with a thickness of 12 mm. Whereas the head diameter was 36 mm, an inner liner thickness of 8 mm was suitable. The contact pressures and von Mises stresses generated during this research can potentially be exploited in estimating the wear of dual-mobility artificial hip joints in general. Contact pressure and von Mises stress reduce with an increasing head diameter and inner liner's thickness. Present findings would become one of the references for orthopedic surgery for choosing suitable bearing geometric parameter of hip implant.

Micro-mechanics investigation of heterogeneous deformation fields and crack initiation driven by the local stored energy density in austenitic stainless steel welded joints

This work investigates the heterogeneous deformation and failure of HR3C austenitic stainless steel welded joints at room and typical service temperatures. Such types of welded joints are widely used in the new generation of fossil fuel power stations and are known to suffer from premature high temperature failure. Observation of in-service failures revealed that cracks may nucleate either in the heat affected zone or in the weld metal. The main objective of this work is to identify the local microstructural conditions and stress–strain fields responsible for both ductile failure and micro-crack nucleation within the weldment at low and high temperatures, respectively. To that purpose, a novel multi-scale micromechanics-based modelling framework is proposed. It relies on representative weld microstructure models digitally reconstructed from electron backscatter diffraction measurements, and dislocation density-based crystal plasticity models to describe the behaviour of individual grains in each weld region. A novel thermo-dynamically consistent relation for the configuration stored energy per unit volume is derived from the crystal plasticity framework.The single crystal models are calibrated and validated from a combination of uniaxial tensile tests on cross-weld specimens using high resolution digital image correlation techniques, representative volume elements of the polycrystals at the macro-scale, as well as micropillar compression tests at the scale of the individual grains. Predictions of heterogeneous inelastic deformation fields within the weldment at both 22 °C and 665 °C, and of micropillar compression behaviour of the individual weld single crystal phases are consistent with experimental data. The experimentally observed ductile failure of the weld metal at room temperature is successfully predicted using a Gurson-type void nucleation, growth and coalescence constitutive model. The suitability of the stored strain energy density and the accumulated plastic strain as crack initiation/creep failure indicators is investigated. It was found that predicted creep lifetimes with either indicator were very similar, and that they were relatively accurate for low stress levels.

Comparative assessment of failure in single shear lap joints fabricated using various joining techniques

The current research endeavour reports the performance of single shear lap joints of flax/PP composite laminates. The joints were fabricated using mechanical joining, fusion bonding (ultrasonic and hot plate joining), and hybrid joining techniques (mechanical/ultrasonic joining and mechanical/hot plate joining). In case of the mechanical and hybrid joining, the effect of the bolt size, and number of bolts (single and double) on the tensile failure load was investigated. Pertaining to mechanical joining, the large bolt size and double bolts recorded higher tensile failure load compared to smaller bolt size and single bolt, respectively. Whereas with double bolts, no increase in the tensile failure load was observed for the hybrid joints, due to reduction in bonded area. The hybrid joints (mechanical/ultrasonic) recorded the maximum tensile failure load compared to all other type of joints. The load-extension behaviour and failure of joints was also examined. Expect mechanical joints, all other joints exhibited structural type of failure. In contrast, the mechanical joints resulted in a net-tension failure mode with failure line passing through the hole. However, the thermal decomposition and crystalline behaviour (XRD spectra) of developed joints did not vary significantly. The morphology of failed joints was examined using scanning electron microscope.

Parametric study for structural performance of spliced hybrid deck beams with UHPC cast in place joints

Splice beams are considered a solution for some difficults in bridge construction and a method for repairing damaged beams. One of the most challenging aspects of this technique is avoiding bond failure between the spliced members. In this study, ultra-high performance concrete (UHPC) was used to splice three beam segments due to its superior performance. This paper investigate the effects of some parameters on the spliced beams by Finite Element Method using computer program ABAQUS. The study have two approaches, first one, a validation study to generate model agree with experimental test results of seven specimens were tested under three bending point load. The main variables being the depth of the joint, the presence of a shear key in the joint, the hybridization of reinforcement, and the addition of dowels in the joint. The model was simulated and achieved good convergence when compared with experimental results, considering the load-deflection response and failure mode. The second approach that investigated various parametric studies, such as reverse cyclic load, repeated cyclic load, thickness of the deck, type of interface joint, reinforcement ratio, strengthening by UHPC layer, and the loading pattern.

Microstructure and Mechanical Properties of Similar/Dissimilar Resistance Spot‐Welded Aluminum Alloys for Aerospace Applications

2195 aluminum–lithium (Al–Li) and 2XXX series aluminum alloys are joined using resistance spot welding for the first time. The macrostructure, microstructure, element distribution, microhardness, and tensile‐shear property of spot‐welded joints are investigated. The microstructure of the fusion zone of 2195/2195, 2195/2219, and 2195/2A14 joints is fine equiaxed spherical grains. It is found that solute segregation of Cu occurs in the grain boundaries in the fusion zone, forming Al2Cu. The microhardness shows that due to the dissolution of strengthening phase T1, the hardness of the fusion zone of the three types of joints is lower than that of the base material. The 2195/2195 joint has the best mechanical performance among the three combinations, with maximum tensile‐shear force and absorbed energy reaching 16893.7 N and 24.9 J, respectively. The fracture surfaces of all three types of joints exhibit mixed ductile‐brittle characteristics.

Energy Consumption for Furniture Joints during Drilling in Birch Plywood.

The purpose of this study is to support eco-design ideas and sustainable manufacturing techniques by examining the energy consumption related to drilling holes for different furniture connections. The experimental model is a simple piece of furniture made from birch plywood with three different types of joints. Eccentric joints, confirmat screws, and dowel measurements of energy consumption with a CNC drilling and milling machine show different values for every kind of connector. The energy consumption was measured using a portable power quality analyzer, specifically the PQ-box 150 manufactured by A:Eberle GmbH & Co. KG Nürnberg, Germany. This device likely adheres to industry standards for energy measurement, ensuring accurate and reliable results. The measurement process involved recording energy consumption at different stages of the machining process, allowing for the analysis of specific cutting work and total energy consumption for various joint types. Dowels exhibit the lowest energy consumption at 0.105 Wh for one furniture joint, confirmat screws at 0.127 Wh, while eccentric joints, despite their higher energy consumption (0.173 Wh), offer enhanced transportability and assembly flexibility of a piece of furniture. Specific cutting power for one selected piece of furniture was 227.89 J/mm3 for dowels, 190.63 J/mm3 for eccentric joints and 261.68 J/mm3 for confirmat screws.

Investigation on fatigue behavior of GFRP hybrid bonded/bolted joint under shear loading based on nondestructive monitoring test and numerical modeling

The GFRP (Glass Fiber Reinforced Polymer) is prospective in bridge and building engineering for its advantageous material property. The connection configuration of hybrid bonded/bolted joint of GFRP is thought superior in mechanical performance compared with the traditional bonded and bolted joints. However, the fatigue issue of this type of joint remains unclear which impedes its engineering applications. The presented work experimentally and numerically investigated the fatigue behavior of the GFRP hybrid bonded/bolted single-lap joints under shear loading. High-cycle fatigue tests on single-bolt, four-bolt, and nine-bolt specimens were conducted to study the failure process, rigidity degradation, failure mode, and fatigue life of the hybrid joints, where the nondestructive monitoring techniques of AE (Acoustic Emission) and 3D-DIC (Three-Dimensional Digital Image Correlation) were adopted, respectively to detect the material damages and overall deformation of specimens. Finite element modelling was further carried out to reveal the fatigue failure mechanism of hybrid joints, in which the property degradation of GFRP plates and adhesive layer were considered. Results showed that the failure process of GFRP hybrid single-lap joints under fatigue shear loading can be divided into four stages: (1) steady and (2) rapid development of adhesive damage, (3) steady and (4) rapid development of GFRP damage, of which the (2) and (4) stages account for less than 3% of the total fatigue life of joint, respectively. Stiffness degradation of 14–35% were read for the tested joints before final failure, and the joints with more bolts performed a superior degradation resistance compared to the less ones. Besides debonding and bolt inclination, the single-bolt joints failed with bearing failure of GFRP material, while the failure mode of multi-bolt joints were dominated by shear failure in GFRP plate with Y-shaped zone. The simulation results well supported the observations in experimental test. Based on the experimental results, the S-N curve of the GFRP hybrid single-lap joints is proposed, which can provide support for the engineering design of this type of joints.

Manners of terminology and description in Galen's anatomy in the ancient Rome and their historical consequences up to the modern time.

The oldest extant anatomy textbooks compiled in ancient Rome were by Galen who described in writing most of the various parts and organs of the body. History tells us that ever since the time of Galen, anatomical terminology would be a necessary and beneficial feature, but it also brought unexpected and annoying consequences into the field. The benefits are readily apparent in the case of muscle terminology. Galen identified more than 150 different kinds of skeletal muscles, most of which were unnamed, hence difficult to identify without professional knowledge of anatomy. Vesalius introduced detailed anatomical illustrations in Fabrica (1543), which made the identification of the muscles easier. Bauhin then introduced proper descriptive names for the muscles in Theatrum anatomicum (1605), which enabled the identification of the muscles without illustrations. After the terminology became complex and diverse, a logically consistent standard nomenclature was established by Nomina anatomica (1895). The unexpected consequences may be found in the terminology of bones and joints. Galen gave 39 proper names for individual bones, and classified and termed the types of bony joints. Many of these terms have survived in modern anatomy as literal translations of the bone terms, as well as the joint terms. The annoying consequences may be found in the terminology of intestines. Galen divided the small and large intestines into three portions, such that the major part of the small intestine suspended by the mesentery was divided into two without sufficient reason. The Latin translations of jejunum and ileum were, respectively assigned to them by Mondino in his Anatomia written in 1316.