Connection Failure Research Articles

An upgraded IoT based Mobile Ad- hoc Network enactment founded on optimized Signal Strength Based Routing algorithm

It is a wireless network with mobile nodes that function independently and communicate with one another with radio waves. When a node gets a packet, they evaluate all of the possible routes before selecting the optimal one. In this way, the capabilities of routing are incorporated into each node of the network. Researchers used ant colonies to find the best path between two sites. The Simple Ant Routing Protocol has improved with the assistant of Internet of Things (IoT). Energy Aware Simple Ant Routing Algorithm (EASARA), a new protocol, considers each node's energy usage. The change improved routing overhead and packet delivery ratio. It also improved communication. EASARA performed better with more hosts. Traffic congestion statistics followed. One parameter estimated host power reserve and connection congestion. Energy-congestion conscious protocol is basic routing algorithm is ECSARA (Energy-congestion based Simple Ant Routing Algorithm). The protocol improves with more hosts. It sends packets faster. Hence, transmission data transfer increased. Energy savings extended the route's lifespan. Signal strength predicted connection failures. This metric chooses a new route. Signal-to-Anchor-Receiver-Attendance based Simple Ant Routing Algorithm is SS-SARA. All host monitors detected strong signals. Communication uses substitute pathways when signal strength goes below a threshold. The protocol improved packet delivery and throughput on congested networks, according to experiments.

Secure Cluster Based Routing Scheme for Neuro‐Fuzzy Assisted MANET in 5G

ABSTRACTThe Fifth Generation (5G) of wireless networks has increasingly focused significantly on energy‐saving methods for mobile communication systems. The objective of combining MANET with 5G communication is to achieve a high data throughout while simultaneously reducing latency and cost. The main issues with MANET are elevated energy use, security, and reduced longevity. The self‐configuring characteristics and dynamic architecture of MANET may lead to frequent changes in topology and resource allocation. This mobility results in frequent connection failures, which increase routing overheads and decrease data transmission dependability. A secured clustering technique is essential to enhance the routing performance and establish reliable routing. In MANET, the cluster mechanism is the prominent way to improve the network lifetime and routing mechanism. The proposed secure cluster routing‐based neuro‐fuzzy logic (SCR‐NFL) establishes a secure cluster mechanism via the use of the Trust value method. It guarantees cluster stability by taking into account node mobility and energy while selecting cluster heads. The important components in the proposed system are Mobility (M), Residual Energy Level (REL), and Trust Value (TV). The neural fuzzy logic system is implemented to handle the data uncertainty and make effective decisions during routing path selections. The proposed SCR‐NFL performance is measured in an NS‐2 simulation environment. The result is compared with the existing Improved Particle Swarm Optimization Algorithm, Trust‐Based Secure Neuro Fuzzy Clustering mechanism and Mobility Aware Energy Efficient Clustering system using Particle Swarm Optimization mechanism. The performance parameters for comparison are packet delivery ratio, average number of clusters, end‐to‐end delay, average number of cluster instances, mobility speed and mobility distance.

A Survey on Emerging Trends and Applications of 5G and 6G to Healthcare Environments

A delay, interruption, or failure in the wireless connection has a significant impact on the performance of wirelessly connected medical equipment. Researchers presented the fastest technological innovations and industrial changes to address these problems and improve the applications of information and communication technology. The development of the 6G communication infrastructure was greatly aided by the use of Block-chain technology, artificial intelligence (AI), virtual reality (VR), and the Internet of Things (IoT). In this article, we comprehensively discuss 6G technologies enhancement, its fundamental architecture, difficulties, and other issues associated with it. In addition, the outcomes of our research help make 6G technology more applicable to real-world medical environments. The most important thing that this study has contributed is an explanation of the path that future research will take and the current state-of-the-art. This study might serve as a jumping-off point for future researchers in the academic world who are interested in investigating the possibilities of 6G technological developments.

Experimental study and theoretical analysis on mechanical properties of prestressed bolted glulam connections under cyclic loading

Due to the development of assembled buildings and public environmental awareness, glulam structures have been widely concerned nowadays which have the advantages in terms of energy efficiency and environmental protection, compared with concrete and steel. However, the beam-to-column connections connected by bolts with slotted-in plates in glulam frame structures generally have some disadvantages, such as the low load-bearing capacity, low stiffness, low ductility, and poor energy dissipation capacity. To improve the mechanical performances of conventional glulam beam-to-column connections against seismic effect, a prestressed bolted glulam connection was proposed in this paper. Twelve connection specimens from four groups were tested and numerically studied under cyclic loading. The results show that the application of prestressing force can improve the brittle failure of connections. Compared with the traditional glulam bolted connections, the application of prestressing force can improve the load-bearing capacity, energy dissipation capacity, ductility and initial stiffness of the connection, and slow down the stiffness and strength degradation. However, excessive prestressing may cause an early failure of the connection. The numerical analysis shows that the bolt diameter and the number of steel bars have significant positive influence on the load-bearing capacity of the connection. Even though increasing bolt diameter would be more efficient for the mechanical behavior of the connection, the transverse splitting failure of glulam would be more likely to occur. A calculation formula for the load-bearing capacity and a theoretical model for the moment-rotation relationship of the prestressed bolted glulam beam-column connections are proposed respectively for practical design. The rotation behavior evaluation of the prestressed bolted glulam beam-column connections indicates that the proposed connections are classified as semi-rigid connections, which can be used for ductility design.

Fault-Tolerant Closed-Loop Controller Using Online Fault Detection by Neural Networks

This paper presents an online model-free sensor fault-tolerant control scheme capable of tolerating the most common faults affecting an induction motor. This approach involves using neural networks for fault detection to provide the controller with sufficient information to counteract adverse consequences due to sensor faults, such as degradation in performance, reliability, and even failures in the control system. The proposed approach does not consider the knowledge of the nominal model of the system or when the fault may occur. Therefore, a high-order recurrent neural network trained online by the Extended Kalman Filter is used to obtain a mathematical model of the system. The obtained model is used to synthesize a discrete-time sliding mode control. Then, the fault-detection and -isolation stage is performed by independent neural networks, which have as input the signal from the current sensor and the position sensor, respectively. In this way, the neural classifiers continuously monitor the sensors, showing the ability to know the sensor status. The combination of controller and fault detection maintains the operation of the motor during the time of the fault occurrence, whether due to sensor disconnection, degradation, or connection failure. In fact, the MLP neural network achieves an accuracy between 95% and 99% and shows an AUC of 97% to 99%, and this neural network correctly classifies true positives with acceptable performance. The Recall value is high, between 97% and 99%, and the F1 score confirms a good performance. In contrast, the CNN shows a higher accuracy, between 96% and 99% in accuracy and 98% to 99% in AUC. In addition, its Recall and F1 reflect a better balance and capacity to handle complex data, demonstrating its superiority to MLP in fault classification. Therefore, neural networks are a promising approach in areas such as fault-tolerant control.

Fault Tolerant Spectral/Spatial Optical Code Division Multiple Access Passive Optical Network.

High-capacity communication networks are built to provide high throughput and low latency to accommodate the growing demand for bandwidth. However, the provision of these features is subject to a robust underlying network, which can provide high capacity with maximum reliability in terms of the system's connection availability. This work optimizes an existing 2D spectral-spatial optical code division multiple access (OCDMA) passive optical network (PON) to maximize connection availability while maintaining desirable communication capacity and capital expenditure. Optimization is performed by employing ring topology at the feeder level, which is used to provide a redundant path in case of connection failures. Furthermore, high transmission capacity is ensured by utilizing a pseudo-3D double-weight zero cross-correlation (DW-ZCC) code. The analysis is performed with Optisystem simulations to observe the performance of the system in terms of bit error rate (BER), received power, and eye openings. It is observed that the introduction of ring topology at the feeder level of the PON does not impact the overall transmission capacity of the system. The system can still support maximum transmission capacity at receiver sensitivities of up to -19 dB. Reliability analysis also shows that the optimized ring-based architecture can provide desirable connection availability compared to the existing system.

A Five-Year Retrospective Study on the Clinical Outcomes of Sacral Nerve Stimulation for Neuromodulation of the Lower Urinary Tract in a Tertiary Hospital.

To assess clinical outcomes in terms of first to second-stage conversion rates, revision rates, and complications for all patients undergoing sacral neuromodulation of the lower urinary tract for the past five years at the Queen Elizabeth Hospital Birmingham. This is a retrospective observational study. Only patients with the first stage of sacral neuromodulation between January 2017 and January 2023 were included in the study. The data collected included age, type of first-stage trial, that is, percutaneous nerve evaluation (PNE) vs. tined lead, response after the first stage, whether a second trial was carried out, response after the second trial, indication for sacral nerve stimulation (SNS), complications, revisions, etc. Results: 94% of the total (198) patients had PNE at the first trial, while 11 (6%)had tined lead. 129 (65%) patients had a positive response after the first trial, 49 (24%) had a negative response, and 20 (10%) had an equivocal response. 15 (8%) patients from the equivocal and negative response group had a second trial with a tined lead, with 53.3% (104) receiving a positive response, making our total conversion rate 69% (136). 100 (50%) patients had permanent implants fitted, 25 (13%) had complications, and 15 (7.5%) required revision. The indications for the revisions were lead migration (66, 33.33%), pain around the battery site (66, 33.33%), connection failure (40, 20%), battery charging problem (13, 6.67%), and device infection (13, 6.67%). The conversion and complication rates are comparable to national standards and documentation in the literature, while the infection rates were lower. Higher conversion rates may be attained when tined lead is used at the first trial.

On the role of local reinforcement in an adhesively bonded AL/CFRP energy absorber under axial loading: A theoretical investigation and optimization

AbstractThis paper aims to develop a novel theoretical model that incorporates the effects of local composite reinforcement using adhesive bonding on the energy absorption of aluminum structures under axial loading. The goal is to optimize energy absorption prior to any connection failures and to prevent uneven structural deformation. Moreover, it strives to reduce the structure's weight and material usage, achieving superior results compared to traditional global reinforcement techniques. The theoretical model was validated through experimental testing and finite element analysis, demonstrating good agreement with the predicted results. The results reveal that increasing the CFRP fiber angle, layer thickness, and number of layers generally leads to improved energy absorption capacity. An optimization analysis was performed to determine the optimal design parameters, yielding a fiber angle of 80°–90°, composite thickness of 1.5 mm, and aluminum thickness of 2.5 is the best configuration, offering the highest specific energy absorption and adequate peak load capacity for maximized energy absorption. The proposed model offers significant improvements over existing approaches, enhancing the predictive capabilities and practical applicability of energy absorption predictions in engineering design.Highlights A novel theoretical model for energy absorption in locally reinforced hybrid AL/CFRP structures. The influence of design parameters, such as CFRP layer count, fiber orientation, and thickness ratio. Optimization to maximize the average crushing force while meeting weight and geometric constraints. Findings can inform the design of safer and more efficient energy‐absorbing structures in various applications.

Shear resistance of UHPC connection for prefabricated reinforced concrete slabs with shear grooves and dowel rebars

The shear resistance of post-cast ultra-high-performance concrete (UHPC) connections for assembled prefabricated normal strength concrete (NSC) slabs having shear grooves and dowel rebars was investigated. The effects of different factors on the failure mode and shear capacity were investigated by direct shear tests of 28 Z-shaped specimens. The influencing factors included the groove configuration, lap and anchorage length of dowel rebar (the height of UHPC connection), strength of NSC prefabricated slab, and rebar location. The failure modes, UHPC connection shear-slip behavior, dowel rebar strains, and failure mechanism were analyzed. The results indicated that two major failure modes might occur in UHPC connection, including tensile fracture within UHPC connection and shear fracture of UHPC grooves at UHPC-NSC interface. Generally, a larger UHPC connection and smaller groove key width could lead to failure in UHPC-NSC interface, otherwise in UHPC connection. Failure in UHPC connection could exhibit a relatively larger peak bearing capacity than failure in UHPC-NSC interface, but also larger post-peak degradation. In addition, increasing UHPC groove width, UHPC connection height, and prefabricated slab NSC strength could increase the shear capacity. Calculation methods of the peak and post-peak residual shear load-bearing capacity of UHPC connection under different failure modes were also proposed, exhibiting good agreement with the test results.

Long-term outcomes in women diagnosed with heart failure in connection to delivery

Abstract Background Heart failure (HF) among young patients may be from various causes, often triggered by heightened physical demands like pregnancy. Data regarding outcomes of women diagnosed with HF in conjunction to pregnancy and delivery are varied. There remains a notable gap in understanding the outcomes observed in women diagnosed with heart failure in conjunction with delivery. Also, long-term follow-up studies are crucial to elucidate the impact of pregnancy-associated HF on future cardiovascular. Purpose To study the interplay between pregnancy, HF, and subsequent cardiovascular risk. Method Using the personal identification numbers (PINs) that all individuals in Sweden have enables linkage of data between different registers. Data from the National Patient Register (NPR), Swedish Medical Birth Register (MBR) and the Cause of Death Register were also used. All women 18 to 50 years of age registered in the in MBR in the period 1st January 1997 to 31st December 2019 were included. Women with first-time HF in relation to delivery were identified using the international classification code for diseases (ICD-10) I50, I42, I43 and 090.3 together with co-morbidities. Every patient was compared with 5 controls without HF from the Total Population Register matched on age at delivery and calendar year of delivery. Outcomes: all-cause mortality, and any cardiovascular disease (CVD) diagnosed during the observation time. Results A total of 286 cases and 1,430 controls were included. The prevalence of comorbidities at baseline for both patients and controls was low; congenital heart disease (1.4%, vs. 0%), pulmonary hypertension (1.0% vs. 0%), valvular heart disease (5.9% vs. 0%), myocardial infarction 0.7% vs. 0%), arrhythmia (5.9% vs. 0%), hypertension (6.3 % vs. 0.1%), (all p<0.05). Preeclampsia prior to HF diagnosis had 31% of patients vs. 0.2% of controls (p<0.001). Patients exhibited higher mortality rates at 4.9% during median follow up 9.0 (IQR 5.6-13.0) years vs. 0.3%, median follow up 9.4 (6.2-13.5) years and hazard ratios (HR) for all-cause mortality HR (95% CI) of 18.20 (5.99 - 55.31) (p<0.001) compared to controls. During median follow up of 3.2 (0.0-9.2) years 60.1% of patients were diagnosed with CVD both at in-/out-patient settings compared with 4.1% in controls during 9.4 (5.8-13.5) years of follow up. Comparing patients with controls the HR (95% CI) was 22.24 (16.50 - 29.96) p<0.0001 for CVD diagnosis during follow-up, see Figure 1. Conclusion In conjunction with delivery, and in the years thereafter, women with heart failure diagnosis had more than eighteen times higher risk of mortality than women without heart failure. The risk of CVD event in the heart failure group is highest in conjunction with delivery. Figure 1. Cumulative incidence functions for all-cause mortality, CVD in- or out-patient visit adjusted for death as competing risk, comparing cases with controls.

Fatigue Strength Analysis of Rail Fastening Baseplate

Superstructural elements of a railway track experience dynamic loads varying over time. As a consequence, this is accompanied by the initiation and accumulation of fatigue damages. Defects in intermediate rail fastening are quite difficult to identify using flaw detection methods, and some can be destructed. In particular, rail fastening baseplates often fail due to insufficient fatigue strength.Purpose: To investigate the fatigue strength of rail fastening baseplate.Methodology: Development of the mathematical model of deformation based on the finite element method (FEM). Strength analysis of the baseplate using the model of a variable-thickness slab resting on a nonlinear elastic foundation. The latter is modeled by a set of rods with nonlinear deformation and parameters determined by compression tests of the baseplate. A mathematical model developed in COSMOS software for the FE analysis of the stress-strain state of the baseplate at a time-varying load from rolling equipment and assembly forces from attaching the baseplate to the sleeper and rail.Research findings: The cyclic loading parameters are obtained at dangerous points of the baseplate and its durability is analyzed at different loads with respect to unevenness of track settlement and failure of bolt connections of rail fasteners. The influence of these factors on actual loads on the rail fastener is determined. It is found that the service life of the baseplate mainly depends on the dynamic load.

Mechanical model analysis of column-footing joints with combined socket-corrugated pipe connection

The socket connection method is widely used in precast column, particularly in seismic regions. However, reducing the socket-depth to lower costs may lead to shear failure in the socketed part of the columns. To address this issue and achieve cost objectives, a new approach combines shallow sockets with corrugated pipes for column-footing joints. Comparative tests were conducted to investigate failure in columns with socket-corrugated pipe connections (SCPC), shallow sockets (SSC), and cast-in-place (CIP). Furthermore, finite element models were employed to validate the experimental and simplified model results. The findings suggest potential shear failure in shallow socket connections, which can be mitigated by using the combined socket-corrugated pipe method that alters force transmission paths. As the axial load ratio increases, both the ultimate lateral load capacity of the specimen and the local stresses at the column base increase. In addition, the ultimate lateral load capacity of the column and the stress of the connection reinforcement are increased by increasing the strength of the longitudinal reinforcement, consequently amplifying the extent of joint area damage. Finally, a simplified strut-and-tie model of the SCPC, validated against numerical and experimental data, accurately represents force paths, ultimate lateral load capacity and failure modes in socket joints.

Investigation of the electrical quality and long-term stability of aluminum ground stud connections in automotive applications

The rapid advancement in the electrification of modern vehicles has led to a continuous increase in electrical consumers for various comfort and safety functions. Ground studs serve as the electrical interface between the conductive vehicle body and the onboard network. Drawn arc stud welding is an economical and established joining process for producing ground stud joints. The circuits in the onboard network are increasingly subject to greater demands regarding current-carrying capacity and long-term stability. Reliable signal and power transmission require minimal contact resistance at the electrical connection points of the ground stud system and must withstand various operating and environmental conditions over the entire service life. In this study, a ground stud made of AlMg5, with a ZnNi-coated steel cap nut was used on a 2.0 mm thick sheet of AlMg3. The electrical connection of the ground studs was made using tinned copper cable lugs and 35 mm² cables. To analyze the electrical resistance behavior in an accelerated test, the ground studs were subjected to a superimposed load with a cyclic current profile for 1008 h under changing climatic conditions. The results show that under the chosen operational and environmental conditions, accelerated aging and intermittent resistance behavior occur. A characteristic drop in resistance during the test indicates the failure point of the electrical connection. The cause of failure can be attributed to media penetration into the electrical contact zone. A failure of the electrical connection was observed after 512 h.

Pyrolysis modelling of insulation material in coupled fire-structure simulations

This paper presents a modelling approach to predict the thermodynamical and thermomechanical behaviour of structures with a layer of insulation material under fire, which takes into account the pyrolysis of the insulation and its effects on the structure. First, an existing 1D pyrolysis model is implemented and verified by theoretical and validated by experimental results. Then the model’s 1D setup is integrated into 3D Heat Transfer (HT) analyses of structures. The obtained thermodynamical results, i.e. temperatures as a function of time and the pyrolysis process, are transferred to a thermomechanical Structural Response (SR) analysis. Mechanical results are then obtained via temperature and pyrolysis-dependent material properties. The resulting HT and SR analyses are demonstrated in fire-structure simulations of facades made of sandwich panels, including their supporting frames with steel sections, and bolt and screw connections, modelled by non-linear spring elements. It is shown that in a short time window of 100 s, pyrolysis is limited to certain zones of the panel and for limited depths. Nevertheless, due to the endothermic process, it reduces expansion and bending of the panels, and consequently results in smaller displacements, and delayed failure of the connections. For longer periods, with connection failures neglected, significant pyrolysis takes place, which influences the temperature distribution in the complete interior of the sandwich panel. However, this has only a marginal effect on the structural behaviour. In conclusion, pyrolysis effects are relevant, can be modelled, and may somewhat reduce fire risks in structures. Future research can combine pyrolysis with advanced modelling of bolt and screw connections, using a two-scale method. As such, all relevant details of structures can be modelled and investigated for different fire scenarios, including fire-structure effects, all still to be validated by experiments.

Shear performance of perfobond leiste (PBL) connectors in engineered cementitious composites (ECC)

Substituting normal concrete with ductile Engineered Cementitious Composites (ECC) is a promising way to address the safety and durability issues caused by cracking in steel-concrete composite structures. To realize a synergistic deformation behavior between steel and ECC, Perfobond Leiste (PBL) shear connectors are preferred to be used owing to their superior shear resistance, shear stiffness, and excellent fatigue performance. This research comprehensively investigated the shear performance of PBL connectors in ECC through experimental, numerical, and analytical approaches. Firstly, the shear load-slip relationships of PBL connectors in ECC and concrete were studied through push-out tests of 36 H-shaped specimens. It indicated that the fracture of penetrating bars dominated the final failure of PBL connectors in ECC, whereas premature concrete spalling happened in concrete specimens. By establishing a refined finite element model, the parametric study was then conducted to clarify the influence of the compressive strength of ECC, hole diameter, penetrating bar diameter, and penetrated plate thickness on the shear characteristics of PBL connectors in ECC. Finally, an analytical model for predicting the shear carrying capacity of PBL connectors embedded in ECC was derived, matching well with the test results.

Developing a novel anticipated inherent risk assessment approach applicable in early stages of process design

Inherently Safer Design (ISD), as one of the most fundamental approaches to process safety, focuses on the innate design features. Numerous tools have been developed to assess ISD and risk-based indices are one of the most elevated of them. Existing indices are limited in modelling consequences or are challenging to adapt in terms of probability. This study introduces the Anticipated Inherent Risk Index (AIRI), a robust tool for rapid risk assessment of the worst anticipated scenarios. It incorporates Furthest Effect Distance of the release from the largest connection, by software, and Representative Failure frequency, which is a relative dataset calculated from renown databases. This presents a relative risk map upon major consequences and their likelihood. AIRI applied to a PDH Fractionation Subunits shows that Heat Pump Compressor Suction Drum (AIRI≈3399) in PP Splitter Section, followed by Propylene Trim Condenser (AIRI≈1931) and PP Splitter Reboiler/Condenser (AIRI≈1798) are the equipment with the highest risk. AIRI is a competent tool for early high-level analysis of equipment risk, which gives useful indications on design and how to improve it. This tool also has the potential to be equipped with vaster frequency datasets and effects analysis and to be incorporated into other process safety studies.

Electrical contact reliability investigation of high-speed electrical connectors under fretting wear behavior

Fretting is one of the common phenomena during the use of electrical connectors, which is usually affected by the working environment and has a significant impact on the electrical contact life. In this work, the influence of different fretting wear conditions on electrical contact failure is studied by combining theoretical analysis, finite element simulation and experimental verification. The mechanical and electrical properties are related through experiments in different environments. It can be concluded that the main causes of electrical contact failure are contact structure deterioration and surface coating loss. Increased fretting cycles aggravate the surface fretting wear of high-speed electrical connectors. The failure of electrical connectors can be delayed by a decrease in frequency and amplitude in addition to an increase in coating thickness. The insertion and withdrawal force gradually decreases due to continuous wear. The failure mechanism of electrical contact during wear is also explained. It provides theoretical guidance for predicting the life of electrical connectors.

Modeling the service life of temporary airfield operational surfaces under multi-pass aircraft trafficking

Expeditionary Airfield (EAF) surfacing systems are designed to create temporary aircraft operating surfaces. Modeling the service life of EAF surfacing systems including the matting system, aircraft, and subgrade, has historically proven difficult, exacerbated by variability between systems and the multitude of mechanisms that can constitute failure. The study presented herein outlines the development and implementation of a performance modeling approach that includes a multi-scale scheme that accounts for local characteristics of the connection points of the EAF matting system, coupled to the global characteristics of the matting array to predict cyclic passes to failure. Finite element studies were conducted for an EAF surfacing system brickwork configuration subjected to aircraft strut loads over varying California Bearing Ratio (CBR) subgrades to calibrate a transfer function to full-scale trafficking experiments. The proposed framework is then used to predict the rate of subgrade deformation for additional lay patterns, which successfully ranked the performance of each relative to full-scale trafficking experiments. An approach is proposed to couple the rate of subgrade deformation with local finite element models to capture increasing joint damage as permanent deformation accumulates, and supplemented by a variable amplitude cycle counting and damage accumulation algorithm that yields reasonable agreement with full-scale experiments while capturing the transition in failure mechanisms at higher CBR values. The results of the study presented herein captures the propensity for end connector and subgrade failure over a range of subgrade CBRs and shows promise for a broader performance framework that can be extended to other EAF surfacing systems, aircraft types, and specific matting lay patterns.

Numerical Design Calculation of T-stubs at Elevated Temperatures

AbstractThe failure of steel connections can lead to the progressive collapse of the entire structure. Accurate modelling of steel connections at elevated temperature allows structural fire engineers to design steel structures that may deal with the severity of a fire. The prEN 1993-1-14 proposes numerical design calculation for the static design check of steel connections. This paper presents a component-based finite element model (CBFEM) to design the T-stubs at elevated temperatures. The generated model is verified and validated against the results from the analytical model and experimental study. The resistance, failure modes and the load-deformation curves are used to validate and verify the CBFEM models for steel connection design at elevated temperatures. The results stated that the CBFEM is a practical design tool to model bolted connections at elevated temperatures and it is possible to apply the recommended 5% plastic limit strain by EN 1993-1-5 for fire design of bolted connections.

Experimental Study on the Competitive Failure of Headed Stud Connectors under Freeze–Thaw Cycles

Experimental Study on the Competitive Failure of Headed Stud Connectors under Freeze–Thaw Cycles