Different Types Of Joints Research Articles

Point-based Models: A Unified Approach for Geometric Constraint Analysis of Planar N-Bar Mechanisms with Rotary, Sliding, and Rolling Joints

Abstract Kinematic simulation of planar n-bar mechanisms has been an intense topic of study for several decades now. However, a large majority of efforts have focused on position analysis of such mechanisms with limited links and joint types. This paper presents a novel, unified approach to analysis of geometric constraints of planar n-bar mechanisms with revolute joint (R-joint), prismatic joint (P-joint), and rolling joint. This work is motivated by a need to create and program a system of constraint equations, which deal with different types of joints in a unified way. A key feature of this work is that the rolling joint constraints are represented by four-point models, which enables us to use the well-established undirected graph rigidity analysis algorithms. As a result, mechanisms with an arbitrary combination of revolute-, prismatic-joints, and wheel/gear/wheel-belt chains without any limitations on their actuation, can be analyzed and simulated efficiently for potential implementation in an interactive computer software and large-scale data generation.

Strengthening flat-die friction self-pierce riveting joints via manipulating stir zone geometry by tailored rivet structures

Achieving high-strength joints with flat surfaces is of significant importance for reducing wind resistance and enhancing aesthetic appeal. In this study, a novel flat-die friction self-piercing riveting (flat-die F-SPR) process is proposed. The rivet flaring without die guidance was achieved through the sophisticated design of rivet structures. Three types of rivets with different internal structures were designed to manipulate the base material flow and microstructure evolution during the joining process. Based on the method of emergency stop, the load-stroke curves, evolutions of macroscopic morphology, and microstructure of the joints made with different rivets were investigated. A novel mechanism for solid-state bonding of joints was proposed to elucidate the generation and evolution of fine grain regions. The results indicate when downward pressure is applied to the material inside the rivet cavity, a central stirring zone appears. By using a rivet with an annular boss structure, the base material flows continuously into the stirring zone and piled up in the rivet cavity, forming a unique conical-shaped fine grain zone. Finally, a comprehensive assessment of the strength of different types of joints and the transition of the fracture modes were conducted based on different lower sheet thicknesses. The joints of Rivet_B and Rivet_C demonstrate 11.1% and 6.9% strength enhancement compared with the joint of Rivet_A, respectively. Two strategies for enhancing the strength of solid-state bonding are proposed by analyzing the joint strengthening mechanism, which offers insights for the optimizations of rivet structures.

Influence of The Type of Laying Joint on The Mechanical Behavior of Prisms Made With Ecological Bricks

Objective: This paper proposes the study of the influence of laying joints on the mechanical behavior of masonry prisms made with ecological bricks. Method: To this end, an experimental program was developed including prisms constructed with different types of joints: laying mortar, adhesive mortar and PVA glue (polyvinyl acetate). Results and Discussion: The adhesive mortar and the conventional mortar were characterized in terms of their compressive strength, obtaining a resistance approximately 1.36 times the compressive strength of the brick (6.92±0.51 MPa), while the settlement was close (0.99%). The average compressive strengths of the prisms were very different, demonstrating that the laying joint has a significant influence on cement-based masonry. It was found that the use of adhesive mortar made it possible to increase the resistance capacity of the prisms to compression by 75%, when compared to prisms made with joints that used PVA glue. However, the laying mortar showed a similar result, at 53%. The rupture mode observed in the prisms made with sticky and conventional mortar was due to traction cracking in the brick units. Research Implications: In this study, it can be concluded that when using ecological bricks with different types of joints, the thickness and type of mortar can have a significant influence on the final strength of the materials, however thin joints tend to maximize the effects defects and reduce the resistant capacity of these masonries.

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.

A study on the formation and failure mechanisms of CF/PPS-metal induction welding joints strengthened by micro-pins

This study proposed a novel hybrid joining technique that combines through-thickness reinforcement (TTR) and induction welding methods to address the challenges of composite-metal joining. The effects of geometrical parameters of micro-pins on the formation and bearing performance of hybrid joints were investigated by combing the experimental and numerical simulation approaches. Two simulation models which included the induction heating transfer and joint tensile failure process were established by COMSOL Multiphysics and Abaqus/Explicit. Subsequently, digital image correlation (DIC) was used to monitor the deformation process of different types of joints under tensile load, and a scanning electron microscope (SEM) was used to observe the welding interface of failed joints. By comparing the experimental and simulation results, it is found that adding pins can significantly improve the mechanical performance of welded joints, with maximum increases of 159% and 1758% in ultimate strength and energy absorption respectively compared to welded joints without interlock structures. This technique presents a potential solution for achieving high-quality metal-composite welded structures.

Research on seismic behavior of prefabricated concrete beam-column joints

In recent years, with the development of society, the construction method of cast-in-place has been unable to fully adapt to the needs of social development. The construction industry has ushered in new development opportunities, gradually to technology, energy-saving and pollution-free development. Prefabricated buildings have been promoted by reducing construction pollution, saving energy and improving labor efficiency. Different types of joints will directly affect the stability and seismic resistance of the whole structure, and also determine the progress of the prefabricated building. Therefore, the prefabricated reinforced concrete beam and column joints are very necessary to study the seismic performance. In this paper, the seismic performance of assembled concrete frame beam and column joints, assembled concrete beam-buckling column-steel restrained support joints and a new kind of prefabricated pin concrete beam-column joints are summarized and analyzed.

Electric performance of hybrid busbar joints under service and high voltage conditions

This paper is focused on hybrid busbar joints with a twofold objective of understanding the differences in electrical resistance under service conditions and evaluating their performance when subjected to hazardous high voltages. Three different types of joints fabricated by conventional bolting, friction stir spot welding and injection lap riveting are selected and two different experimental setups are used to allow the hybrid busbars to be tested up to high voltage electrical discharges of 30 kV. The work is an enhancement of previous experimental and numerical investigations of the authors in the field with results showing no signs of damage or catastrophic failure when the different types of busbars are subjected to high voltage electrical discharges. Results also confirm the good overall performance and advantages of injection lap riveted hybrid busbar joints against bolted and friction stir spot welded.

Extrapolation Paleostress Orientations Deduced from Joints Analyses at Spi Rais and West Part of Chai Gara Anticlines, Duhok Area, Kurdistan Region, Iraq

Spi Rais anticline (East part of major Bekhair anticline) and western part of Chia Gara anticline were chosen to study joint paths. They are located within the highly folded zone of the western zagros fold and thrust belt, Iraqi segment. These anticlines arranged in an en-echelon pattern and they expose rocks range in age from Late Cretaceous to Late Miocene. The Late Cretaceous (Campanian – Maastrichtian) succession represented by Bekhme and Shiranish Formations. The lithologies of these rocks are competent and consist of limestone, dolomitic limestone and marly limestone whichare favorable to joint development. Different types of joints were developed in such rocks due to stresses resulted from collision between Arabian and Eurasian (Turkish and Iranian) plates. The joint sets and systems are the most abundant fractures in the rocks of the study area. The chronological relationships of the joints refer that the area had witnessed multiple tectonic pulses in the form of compressional and extensional stresses. The stereonet and the Win – Tensor programs were used to plot the attitudes of joints and deduce their paleostresss orientations. Furthermore, the orientations of deduced paleostresses were plotted onto geological map of investigated area and simulated as paleo trajectories as well. The deduced paleostress direction responsible for folding in traverse 1 was (356° - 195°), in traverse 2 (330° - 168°) and in traverse 3 (353°- 163°).

Damage Assessment of Segmental Concrete Beams with Different Types of Joints and Prestressed External Tendons

Precast segmental beams with prestressed external tendons have become increasingly common in bridge constructions owing to the merits of high-quality control and fast onsite construction with minimum environmental impact. Due to the nonlinear characteristics of the dynamic behavior of these segmental beams associated to the joint opening, the traditional condition monitoring and damage assessment methods based on vibration parameters either in time or frequency domain using the linear theory are unsuitable. To overcome this challenge, this paper proposes a damage assessment method through analyzing nonlinear structural dynamic responses for monitoring the conditions of segmental beams with different joint types and prestressed external tendons. Two damage indices are proposed to identify the occurrence of damage and to qualitatively indicate the damage severity. In the proposed approach, the measured dynamic responses of the segmental concrete beams under hammer impact are first adaptively decomposed into a finite number of mono-components by using variational mode decomposition (VMD) technique. Then, the instantaneous frequencies of the decomposed mono-components from the dynamic responses are obtained by conducting the Hilbert transform. Two damage indicators are defined for the damage assessment and for the identification of the damage location, respectively. Three four-span segmental beams with different types of joints (i.e. dry joints or epoxy joints) and prestressing tendon types (i.e. steel and carbon fiber reinforced polymer tendons) were constructed and tested under five loading levels with different damage severities. The feasibility and accuracy of the proposed approach are verified by comparing the identification results with the secant and initial stiffness extracted from the load–deflection curves at different loading levels. The effectiveness of these two damage indicators is also validated with the structural conditions observed in the tests. The results show that the proposed approach can successfully identify damage in segmental concrete beams.

An experimental investigation on the influence of environmental ageing on strength and fatigue behavior of different single lap joints

It is essential to examine the performance of CFRP and aluminum specimens after being exposed to environmental aging and to develop a technique that can predict their mechanical function. However, there is limited research on the static and fatigue strength of adhesive, mechanical, and hybrid joints (adhesive/mechanical) after environmental ageing. The study aims to examine the effect of thermal and hygrothermal ageing on the static and fatigue performance of three-point bending joints. Three groups of samples were prepared: I) unaged, II) thermally aged, and III) hygrothermally aged. The bending performance of three different types of joints (bonded, bolted, and bonded/bolted) was evaluated by conducting bending tests using three distinct types of adherends: ATA (Aluminum-to-Aluminum), CTC (Composite-to-Composite), and ATC (Aluminum-to-Composite). Also,the strength of the joints was measured and assessed for both static and fatigue (at three different levels of loading using the new fixture) loading. Static tests showed that bonded/bolted CTC specimens had the highest strength, and hygrothermal and thermal conditions significantly affected the static performance of the three types of joints and substrates. Under fatigue load, the highest fatigue life was observed in bonded, bolted, and bonded/bolted specimens for ATA, ATC, and CTC, respectively. In a bonded/bolted single lap joint, the static and fatigue strength consists of two steps: the initial step corresponds to the strength of a bonded specimen, and the next step starts when the bonded joint fails and fits the strength of a bolted joint. Finally, both ageing and static load percentage reduced the fatigue life and shifted the failure mode of the joints.

Review on Analysis of RCC beam, Column Joint and RCC Shear wall using FRP strengthening on Ansys Software

Abstract: After occurrence of recent earthquakes in the most of world parts, scientific committees for reducing natural disasters and research centers declared based performance design, investigation faults, retrofitting, rehabilitation, new researches are related to strengthening of structures, notice performance, importance of structure, surface of earthquake levels, considering economic and feasibility. One of streningthening method of RC frame is using FRP laminates. Beam and column where intersects is called as joint or junction. The different types of joints are classified as corner joint, exterior joint, interior jointetc. on beam column joint applying quasi-static loading on cantilever end of the beam. and study of various parameters as to be find out on corner and exteriorbeam column joint i.e. maximum stress, minimum stress, displacement and variation in stiffness of beam- column joint can be analyzed in Ansys software (FEM Software) RC shear walls are considered one of themain lateral resisting members in buildings. In recent years, FRP has been widely utilized in order to strengthen and retrofit concrete structures. Significant experimental research has been conducted over the past three decades on hysteretic behavior of beamcolumn joints of RC frames under cyclic displacement loading. The various research studies focused on corner and exterior beam column joints and their behavior, support conditions of beam-column joints. Some recent experimental studies, however, addressed beam-columnjoints of substandard RC frames with weak columns, poor anchorage of longitudinal beam bars and insufficient transverse reinforcement. the behavior ofexterior beam column joint is different than the corner beam column joint.

A comparative numerical-experimental investigation on the tensile behaviour of bonded, rivetted and hybrid composite joints configurations

This paper deals with the development of accurate numerical models to predict the tensile mechanical behaviour of composite joints. The problems of damage initiation and propagation in composite joints for an economic solution with minimized oversizing is addressed. Different types of joints (Single Lap Joint, Single Strap Joint, Joggle Joint) and couplings (bonded, rivetted, hybrid) have been combined to find out the most suitable and reliable joining technique depending on the design constraints. On the basis of preliminary DCB and ENF tests, the characteristics of the adhesive material (stress limits and fracture energies) have been determined. These data have been employed for the numerical simulations on bonded and hybrid (bonded/rivetted) joints. The introduced numerical models, taking into account geometrical non-linearity and progression of damage in composite plies, have been preliminary validated by ad-hoc experimental tests to demonstrate their effectiveness in simulating the mechanical behaviour of general composite joints.

Study on fatigue performance of double cover plate through-core bolted joint of rectangular concrete-filled steel tube bundle wind turbine towers

Rectangular steel tube concrete bundle wind turbine towers is a new type of tower structure with high prefabrication, convenient installation, convenient transportation and good integrity.Based on the uniaxial tensile test and fatigue loading test of the double cover plate through-core bolted joint, the stress condition of the key connection parts of the structure is analyzed, the S-N curve of the joint under parameter expansion is summarized, and the Weibull distribution test is carried out for the fatigue life of the concrete inside the joint. Finally, the fatigue damage of the joint are analyzed. The results show that the failure mode of the double cover plate through-core bolted joint under fatigue loading is bolt shear; Through S-N curve fitting, the S-N curve expression and fatigue limit value of different types of joints are obtained. It is found that under the shear failure mode, the fatigue limit of different types of joints is higher than the limit value specified in GB50017–2017, EC3 and AISC-360; The fatigue life of concrete at different loading factors conforms to the two parameter Weibull distribution.The damage analysis of the joint through the high cycle fatigue damage model shows that the trend of a sharp increase in the damage rate of the joints in the late loading period can better explain the phenomenon of instantaneous fracture. The research results of this paper can provide reference for the analysis, research and application of wind turbine towers.

Seismic response study of a steel lattice transmission tower considering the hysteresis characteristics of bolt joint slippage

Ignorance of the influences of bolt slippage effects on transmission towers will lead to the underestimation of the deformations of the transmission towers. Therefore, the responses of transmission towers under different load scenarios cannot be accurately predicted. This will result in an incorrect estimation of the ultimate load-bearing capacity and the failure mode of transmission towers. Recently, studies of the influences of bolt slippage effects on transmission towers have been limited to static analysis only. This paper presents a dynamic response study of transmission towers considering bolt slippage. This paper first presents the test results of the mechanical properties of typical bolt joints in transmission towers under cyclic and monotonic loads. The numerical models of typical joints and the hysteresis curves of each joint under cyclic loads are then proposed, and the numerical models of hysteresis curves are validated through laboratory tests. From the various simulation results on the different types of joints, the hysteretic curves of each joint are obtained, and the skeleton curves are extracted. The numerical models of the slippage effect of transmission tower joints are then integrated into the tower–line system model for seismic analysis. The numerical simulation results indicate that neglecting the dynamic effect of bolt slippage will underestimate the seismic response of transmission towers, which will directly lead to an overestimation of the dynamic resistance capacity of the transmission towers. Furthermore, the higher the earthquake magnitude is, the more serious the influence.

Tensile Strength of Adhesively Bonded and Hybrid (Bonded/Riveted) Dissimilar Single-Lap Joints

Glass fiber-reinforced composites are commonly employed as structural materials in many fields. In addition, glass fiber-reinforced composites are frequently used with metals, particularly in the automotive and aerospace industry. In this context, the tensile strengths of simple and hybrid single-lap joints having similar (i.e., aluminum/aluminum and composite/composite) and dissimilar (i.e., aluminum/composite) plates were investigated experimentally in this study. At this point, 6061 aluminum alloy and E-glass/epoxy composite plates were used as the adherends and Araldite 2014-1 was used as the adhesive. The composite adherends produced using the vacuum infusion technique consist of E-glass/epoxy laminates with [0°/90°/+45°/−45°]6 stacking sequence. Two different types of joints (i.e., adhesively bonded and bonded/riveted) were employed for similar and dissimilar joints. In addition, both 3-rivet and 4-rivet joints were used in bonded/riveted joints. The results revealed that the strength of the joints could be considerably increased with the addition of rivets to the adhesively bonded joints. In particular, the results showed that the strength value of the bonded/4-riveted joint is 5.7 times higher than the adhesively bonded joints.

An Assessment of Seal Ability of Tubing Threaded Connections: A Hybrid Empirical-Numerical Method

Abstract Oil and gas development has strict requirements for the seal ability of premium threaded connections (PTCs) of tubing. Assessing the seal ability of joints can help reduce the risk of leakage after running the string. Using experimental methods to investigate thread sealing capability is time-consuming and expensive, and furthermore, the results of the finite element simulations are not accurate enough. To better address this issue, a hybrid method is utilized as an advanced solution: we establish a geometric nonlinear model and tie it to an empirical formula based on experimental data. With this method, we explore the variation of the seal ability of a PTC within the actual working load range. Our results indicate that the increase in internal pressure increases the contact pressure on the contact path to a certain extent, but reduces the seal ability of the joint. Also, an increase in the axial tensile load will significantly impair the performance of the joint to seal. Eventually, an economic appraisal is obtained by considering the seal ability of different type of joints. The described workflow may be adopted in other wells to predict the potential string leak problems induced by premium threaded connections with cheap computational costs, and to compare the seal abilities of different PTCs for optimal purposes of saving drilling costs.

Analysis and assessment of life-cycle carbon emissions of space frame structures

The construction industry takes up a significant part of global energy consumption and carbon emissions, and thus accurate calculation and evaluation of full life-cycle energy consumption and carbon emissions of different types of building structures are important for low carbon-oriented structural design. Large-span structures usually consume more materials, need more complex construction processes, and thus have a larger environmental impact. In this study, the life cycle assessment of the carbon emission of space frame structures which is a classical type of large-span structure is conducted. Space frame structures with bolted spherical joints and space frame structures with welded hollow spherical joints are considered. The life cycle of a space frame structure is divided into four phases including component production, construction, maintenance, and demolition. The tiered hybrid method that combines process-based calculation and input-output analysis is adopted to evaluate the carbon emission of space frame structures. Parametrical studies on the height-span ratio and grid number are carried out using the proposed assessment scheme. The carbon emissions of the space frame structures with different types of joints are investigated and compared. It is found that lower material consumption does not always result in lower carbon emission, and thus it is necessary to evaluate the life-cycle carbon emission during lower carbon-oriented design of space frame structures. An equation for approximately and quickly estimating the carbon emission of space frame structures is fitted from the material consumption to carbon emission datum obtained from the parametrical studies. This study provides a useful reference for the carbon emission assessment and low-carbon oriented design of space frame structures.

Study on Blasting Effect Optimization to Promote Sustainable Mining under Frozen Conditions

In order to respond to the theme of national green and healthy sustainable development and in response to the problems of large block rates and pollution of the environment after the blast mining of underground rocks in alpine areas, we conducted research on the joints of underground rocks and the blastability of frozen rocks. According to the actual geological conditions of an underground mine blasting in Heilongjiang Province, three kinds of joint blasting geometric models were established. The rock mass blasting process of different types of joints was simulated by LS-DYNA software and the influence law of joints on rock mass blasting was summarized. The blasting crater test and the triaxial compression test of frozen rock were carried out. Combined with the blasting fragmentation characterization function (R-R and G-G-S), the blasting fragmentation, strength and stiffness of frozen rock at different temperatures were obtained. Based on the above, the blasting parameters of a multi-joint underground rock mass in an alpine region were optimized: hole spacing 4.0 m, row spacing 2.5 m, hole depth 11.5 m, V-type initiation network. The optimized blasting parameters significantly improved the mining efficiency and reduced the large lump rate to 3.1%. In order to promote the sustainable exploitation of resources in alpine regions, this study optimized the blasting technology of underground rock mass.

Experimental investigation on the tensile behaviour of welded RHS high strength steel X-joints

The newest version of prEN 1993-1-8 (2022) prescribes a material factor (Cf) to reduce the design resistance of welded joints made of high strength steel (HSS) mostly due to the lack of available experiments, given the less ductility of HSS compared to mild steel. Additionally, it is stated that the material design yield strength should not exceed 0.8 times the ultimate strength (fu) for the chord punching shear failure and the tensile brace failure. The mechanical background behind Cf and the 0.8fu restriction for different types of joints and loading conditions is vague. In this paper, the validity of Cf and the 0.8fu restriction is investigated experimentally by considering 18 welded rectangular hollow section X-joints tested in tension. A bi-linear model, which is suitable for an elasto-plastic global analysis considering the post-yielding stiffness, is proposed to characterize the nonlinear behaviour of the joint. The predicted resistance and failure mode, with and without considering the Cf and/or the 0.8fu restriction, are compared to the experimental results. In addition, the predicted resistance corresponding to the experimental failure mode is investigated. It is concluded, based on the tested joints in this paper and literature, that Cf and the 0.8fu restriction are not necessary for the design according to prEN1993-1-8. However, the predicted brace failure resistance is unconservative for tested joints that failed by brace failure if Cf for S700 or the 0.8fu restriction for all steel grades is not considered.

Shaking table experimental study on models of steel buildings with different types of joints

The aim of this paper is to study the response of models of steel buildings with destroyed and non-destroyed joints. The study was conducted experimentally using the shaking table tests. Two steel models were considered. Several types of joints were taken into account: totally destroyed joints, partially destroyed joints, welded joints and joints stiffened with additional metal. Six ground motions were taken into account. The acceleration time histories were measured at the top of these two models of steel buildings. The results of the study show that the steel models with partially destroyed joints experienced higher levels of accelerations at their top, as compared to the steel models with totally destroyed joints. It was also concluded that the steel models experienced higher peak accelerations at their top in the case of welded joints and stiffened joints, as compared to the case with totally destroyed joints and partially destroyed joints.