Types Of Imperfections Research Articles

Imperfection-insensitive flexible random network materials with horseshoe microstructures

Flexible network materials with periodic constructions of bioinspired wavy microstructures are of focusing interest in recent years, because they combine outstanding mechanical performances of low elastic modulus, high stretchability, biomimetic stress-strain responses, and strain-limiting behavior. In practical applications (e.g., bio-integrated devices and tissue engineering), small holes are often strategically designed in flexible network materials to accommodate functional chips and other individual electronic components. The design of imperfection insensitive flexible network materials is therefore of pivotal importance. While random structural constructions are believed to play crucial roles in the excellent mechanical properties of many biological materials, the effect of randomness on mechanical performances of flexible network materials has not yet been explored. In this work, a class of two-dimensional (2D) flexible random network materials consisting of horseshoe microstructures is introduced. Their node distance distributions, which can be characterized by a parameter related to randomness, follow well the Weibull probability density function. Combined numerical and experimental studies were performed to elucidate the effect of randomness on nonlinear mechanical responses of flexible network materials. Simple analytical equations are obtained for their key mechanical properties (e.g., strength, stretchability, and initial modulus). Flexible random network materials (with randomness ≥ 0.4) were found to exhibit approximately isotropic J-shaped stress-strain responses, even in the high-strain regime. Finally, we study the reduction of stretchability and strength in random network materials induced by different types of imperfections (e.g., a missing filament, a missing node, or many missing filaments). In comparison to periodic network materials, random network materials (e.g., with randomness ≥ 0.6) show much smaller reductions of stretchability/strength when the imperfection appears, and are therefore more imperfection-insensitive. Such an imperfection-insensitive behavior can be mainly attributed to a relieved stress concentration around the imperfection of random network materials.

A proposed approach for failure analysis of lattice transmission towers considering geometric imperfection effects

Different types of geometric imperfections can be observed in power transmission lattice towers. These imperfections include eccentricity resulting from the utilization of steel angles, joint slippage, initial crookedness, and dimensional tolerances in the cross-section of lattice tower members. These imperfections contribute to intricate structural behavior, particularly in members experiencing compressive forces. A comprehensive examination of geometric imperfections in lattice tower is crucial, yet research in this vital area is limited. Therefore, for proper modeling of these imperfections and better prediction of lattice tower failure capacity, it is necessary to provide a suitable approach in the modeling of the tower. In the present paper, a modeling method has been developed to analyze the failure of lattice towers, considering geometric imperfections effects (such as eccentricity, joint slippage, initial crookedness, and cross-section dimensional tolerances in the members). The results of the proposed modeling method have been compared with the results of a full-scale failure test conducted on a 400 kV tower. The results of the study show that the proposed modeling method, considering the effect of geometric imperfections, provides a suitable prediction of the tower’s load-carrying capacity. Also, to investigate the effects of each geometric imperfection, various finite element numerical models were established, and their force–displacement responses were evaluated. The results show that to make an acceptable estimation of the tower failure behavior, it is not enough to introduce geometric imperfections individually into the analysis. Rather, considering the collective effect of imperfections altogether can give an acceptable estimate of the tower’s load-bearing capacity.

Anthropomorphic Sad Expressions Reduce Waste of “Single” Imperfect Food

ABSTRACTPoint‐of‐sale anthropomorphism—attributing human characteristics to nonhuman entities—has been shown to increase evaluations of food that deviates in shape or form from consumer expectations (“imperfect food”). However, while previous research has included the use of primary emotions to manipulate anthropomorphism, it is unclear whether depicting imperfect produce with happy or sad emotional expressions is more effective in boosting choice of such produce. This research addresses this gap and additionally examines a novel type of imperfection: when produce is torn off the bunch it normally comes in. A field study conducted at a large food retailer in Germany revealed that sales of “single” bananas significantly increased when they were anthropomorphized with sad emotions compared to when they were anthropomorphized with happy emotions or not anthropomorphized. Across three preregistered online experiments, this research corroborates the effectiveness of sad emotional expressions in boosting purchase intentions, establishes compassion as the underlying process, generalizes this effect to other produce (i.e., tomatoes), and shows that a price discount eliminates this effect. The findings of this research are particularly relevant for food retailers aiming to increase purchases, and thus reduce waste, of fresh produce that has become a loose “single.”

Influence of geometric imperfections on the seismic performance of unanchored liquid storage tanks

This paper investigates the inelastic buckling of imperfect unanchored cylindrical steel tanks subjected to seismic loads. A pushover-based seismic analysis was conducted considering the impulsive hydrodynamics pressures on the wall and base plate of the tank. Material and geometric nonlinearities were considered in the seismic analysis of the tanks. Three types of imperfections were analyzed: imperfections due to impacts, imperfections located at the bottom of the tank wall, and imperfections with the first buckling mode shape. The buckling analysis was performed for two tank geometries (one slender and one broad), and the effect of the imperfections was correspondingly evaluated. The considered imperfection amplitudes were established according to the New Zealand seismic design code for storage tanks. Additionally, amplitudes that exceed the normative limit were evaluated to further analyze the sensitivity to imperfection. The analysis revealed that geometric imperfections reduce the peak ground acceleration needed to induce buckling failure. Specifically, the critical peak ground acceleration for the slender tank decreased from 0.195 g to 0.180 g for the slender tank and from 0.600 g to 0.535 g for the broad tank. This buckling capacity reduction due to geometric imperfections were about 8 % and 11 % for the slender and the broad tanks, respectively.

Postbuckling behaviour of anisotropic shear deformable laminated cylindrical shells with general imperfection distribution subjected to torsion

Composite cylindrical shells belong to typical basic structure in engineering, whose buckling and postbuckling behaviours determine the stability and safety of overall structures under complex service loadings. In this paper, a nonlinear mechanical model for anisotropic laminated composite cylindrical shells with general distributed initial imperfection is derived to analyse the buckling and postbuckling behaviours under torsional loads, in which the general distributed imperfections are represented by a generic two-dimensional imperfection function reconstructed by using measured data. Based on a higher order shear deformation shell theory, the governing equations are established with consideration of von Kármán–Donnell-type of kinematic nonlinearity and the coupling effects of extension/twist, extension/flexural and flexural/twist. By using a two-step perturbation technique, a new set of explicit solutions is obtained to determine the buckling loads and postbuckling equilibrium paths of the torsional composite cylindrical shells. Furthermore, the internal quantitative relationship between the shear stress with torsional characteristics along with an associate compressive stress of anisotropic laminated shell is for the first time obtained. Numerical analyses are performed to validate the accuracy and effectiveness of the present explicit solutions, and obtain the postbuckling response of different types of imperfections, anisotropic laminated cylindrical shells with different values of shell parameters.

Influence of random geometrical imperfection on loading capacity of scaffold based on stochastic numerical model

The existing data indicate that two-thirds of engineering accidents occur during construction among which engineering accidents caused by scaffold collapse account for a large proportion. Due to the complex mechanical behavior of connection and random nature of scaffold system caused by random geometrical imperfection, the reliability of scaffold system is lower than other kinds of building structures. However, the method considering the random geometrical imperfection is limited. To facilitate the analysis of random geometrical imperfection, the original numerical algorithm is proposed based on ANSYS Parametric Design Language. Through proposed method, two types of geometrical imperfections, i.e., the nodal location error and initial curvature can be automatically considered. The randomness in initial curvature includes random magnitude and random direction. The established numerical model is as close to reality as possible and the process of establishing stochastic numerical model can be automatically finished. The only work that needs to be done is to enter the dimensions of the scaffold. Except the propose of numerical algorithm, the objective of this study is to reveal the influence of geometrical imperfection on random distribution of loading capacity of scaffold system under different load conditions. The influence of random geometrical imperfection on probabilistic distribution of loading capacity is systematically investigated. The results indicated that there may be several buckling modes exist and the buckling mode occurred in actual condition is closely related to the random distribution of geometrical imperfection. The load factor of internal post (point 3) is 8 %–12 % larger than that of corner post. The load factor of side post is 4.7 %–7.2 % larger than that of corner post. The ultimate bending capacity Mu has little influence on the loading capacity of scaffold system when the initial bending stiffness ko is small enough.

Fourier representation of geometrical imperfection for probabilistic buckling analysis

This research studies the first part of the failure of a compression member structure due to buckling. This unstable equilibrium collapse, exposes brittle failure which occurs suddenly and therefore should be avoided wherever possible. Unavoidable geometric imperfections due to structural fabrication, will weaken the structure against buckling. The behavior of bar under compression will be closely examined by taking a set of geometric imperfection data synthesized from previously available from the measurement of conical shells. Therefore, the two-dimensional surface imperfection is converted into several one-dimensional imperfection with some probability properties. In order to obtain a comparison tool for different type of imperfections, Fourier analysis is used to convert the imperfection into coefficients of trigonometric function. By examining the coefficients, geometric imperfection patterns introduced by a certain fabrication process are able to be identified. The study successfully demonstrates the applicability of Fourier analysis in representing inherent geometric imperfections as an initial step for conducting probabilistic buckling analysis. Fourier analysis has shown its capability to simultaneously characterize imperfections in two crucial parameters - the magnitude and configuration of the imperfection.

Wind buckling analysis of cylindrical shells with various geometric imperfections

This study addresses the complexity of buckling behavior in cylindrical shells subjected to non-uniform wind loading, emphasizing the significant impact of geometric parameters on buckling patterns. Cylinders with varying aspect ratios exhibit distinct linear and nonlinear buckling behaviors, complicating the determination of the most detrimental structural imperfections across different geometries. Notably, imperfections affecting stocky cylinders may be less impactful for slender ones. This paper introduced equations for calculating linear critical pressures under wind loading, followed by an extensive numerical analysis assessing the imperfection sensitivity in anchored cylindrical shells of uniform thickness with diverse aspect ratios. Two types of geometric imperfections were employed to assess their influence on the nonlinear buckling strength of cylinders with varying geometries. Results demonstrate that eigenmode imperfections predominantly compromise the buckling strength of stocky cylinders, whereas nonlinear incremental mode imperfections significantly influence the nonlinear critical pressures of intermediate-length and slender cylinders. Consequently, empirical expressions have been formulated to calculate the imperfection reduction factor, offering a precise evaluation of nonlinear buckling pressures in imperfect cylinders under wind loading.

“TimeOntoImperfection”: An OWL 2 ontology to representing temporal data imperfection using imperfection theories

Dealing with temporal data imperfection is a crucial issue in several application domains. In fact, failure to handle these imperfections can have significant consequences and lead to incorrect analysis and decision-making. This is particularly true when handling imperfect temporal data inputs in applications for Alzheimer’s patients as a real example. In this context, there is a need for a global ontology that provides a semantic representation of temporal data imperfection. In the literature, there is a big number of ontologies that represent data. Some represent only perfect temporal data. Some others represent imperfect data but not temporal ones. To the best of our knowledge, there is no ontology that represents temporal data imperfection. In this paper, we represent “TimeOntoImperfection”, a usable global ontology that represents four types of imperfection: imprecision, uncertainty, both uncertainty and imprecision and conflict. We describe the structure of “TimeOntoImperfection”, then we conduct a case a study in which we illustrate the usefulness of our ontology. Finally, we introduce the validation part in the context of CAPTAIN MEMO - an ontology based memory prothesis dedicated to alzheimer patients- and we discuss the encouraging results derived from the evaluation step.

Equivalent sway imperfections and sway-member imperfection combinations for GMNIA-based steel design

Two types of geometric imperfection typically need to be considered in the analysis and design of structural systems: global frame out-of-plumbness, also referred to as sway imperfections, and member out-of-straightness, also known as bow imperfections; the effect of local cross-section imperfections is generally accounted for through cross-section resistance checks. For modelling convenience, equivalent geometric imperfections are often employed to allow for the combined influence of initial geometric imperfections and residual stresses. For design by geometrically and materially nonlinear analysis with imperfections (GMNIA), amplitudes for equivalent bow imperfections for members are provided in EN 1993–1-14; however, no provisions exist for global sway imperfections. Therefore, equivalent sway imperfections suitable for use in the design of steel structures by GMNIA ϕ0,GMNIA are established herein. Two proposals for calculating ϕ0,GMNIA are presented: (1) ϕ0,GMNIA=ϕ0,geom+α/100, with ϕ0,geom representing the pure geometric sway imperfection, and (2) ϕ0,GMNIA=α/50. In both proposals, the varying degree and influence of residual stresses for different cross-section geometries and axes of buckling is captured by the imperfection factor α, as defined in EN 1993–1-1 for carbon steel and EN 1993–1-4 for stainless steel, respectively. A flow chart that provides guidance on the appropriate selection of frame and member imperfections to avoid duplication of the effects of residual stresses in design by GMNIA is also presented.

1/2 and 1/3 Subharmonic Resonance Behaviors of a Rotating FG-CNTRC Beam with Geometric Imperfections

This paper aims at investigating 1/2 and 1/3 subharmonic resonances of a rotating functionally graded carbon nanotube-reinforced composite (FG-CNTRC) beam in the presence of geometric imperfections. A general function is introduced to denote three types of imperfections containing sine, global, and local modes. At first, based on the von-Kármán geometric nonlinearity assumption, the forced vibration equation is set up. Then, the Galerkin method and multiple scale method are utilized to study subharmonic resonance behaviors. Finally, coupled effects of FG-CNTRCs, rotating motion, and geometric imperfections on subharmonic resonance responses are investigated. It is found that a specific range of the excitation amplitude and frequency motivates the subharmonic resonance behavior. The coupling of geometric imperfections and geometric nonlinearities generates the 1/2 resonance phenomena, and geometric nonlinearities result in the 1/3 resonance behavior. Both the imperfection mode and amplitude can affect the resonance response and resonance regions. Moreover, in contrast with the 1/3 subharmonic resonance, geometric imperfections produce greater influence on the 1/2 subharmonic resonance.

Development of plant integrity inspection on the API 5L X65 material under humid conditions: emerging fitness for service assessment approach

This work reports the development and corresponding monitoring of pipeline integrity inspection in the arid zone, which typically experiences external corrosion. The recent method poses the challenge which indaquate to synchronize the internal and external corrosion monitoring of API 5L X65 material trunklines and flowlines owing to imperfect types of inspection on the external progressive damage only. Red-clay soil, soil porosity, oxygen content, and moisture become critical parameters for controlling the corrosion of the above conditions. The combination of ultrasonic guided wave test, visual inspection, and design life calculation is implemented to address the above challenges. Based on the results, trunkline B (12-inch) is more severe than A (18-inch), with the shorter measured remaining thickness and remaining life of 4.35 mm and 1.9 years. External corrosion and visual inspection results show that sand threatens corrosion. The external corrosion product is evident at the 3 and 6 o’clock positions, corresponding to the exposure of the buried pipelines to moisture. The maximum metal loss in the trunk is 14.5 %, which confirms the environment of trunkline B. The internal corrosion has little effect on the integrity of the plant. Despite the three fluid phases inside the flowlines and trunklines, the measured corrosion rate on the coupon is relatively lower. The highest recorded corrosion rate is 0.443 mmpy, while the contribution to internal corrosion from the rest of the monitor well is insufficient. This research is designed to model the strategy to utilize instrumentation of Ultrasonic tests and human intervention in corrosion mitigation

Evaluation of the Applicability of Digital Photogrammetry-Based Initial Imperfections on NLFEM Ultimate Strength Analysis of Ship- Type Stiffened Plates

In this study, the effects of initial imperfections on the ultimate strength values of ship-type stiffened plate structures are discussed and analysed from the point of view of how the initial imperfection forms are obtained. Ship stiffened panels are subjected to complex loading conditions during their operational lifespan. Accurate prediction of their strength and failure modes necessitates a thorough understanding of the effects of various imperfections on their behavior. Two primary sources of initial imperfections are considered: the buckling mode shapes resulting from linear eigenvalue buckling analysis and measurements based on digital photogrammetry. Buckling mode shapes, arising from the manufacturing process are extracted using linear static structural analysis. Digital photogrammetry is employed to capture and quantify imperfections by analysing high-resolution images of the physical structure. Numerical investigation is conducted by incorporating these two types of initial imperfections into non-linear finite element method (NLFEM) calculations. The buckling mode imperfections are applied as geometric perturbations, while the photogrammetry-based imperfections are incorporated as statistically representative deviations from the ideal geometry. Stiffened panel's structural response is analysed under longitudinal uniaxial compression. A new NLFEM project schematic has been utilized instead of the procedure outlined in the technical circular S.P 01/19 by Türk Loydu, which has been discontinued after ANSYS® Workbench™V.2019R2. This is proven by two validation case studies in ANSYS® Workbench™2022R2 version for considering buckling mode initial imperfections. A case study is then conducted using a 3D model of a stiffened plate panel, which is fabricated in a shipyard located in Trabzon, created by Photomodeler V. 2023.3.0.238 employing the digital photogrammetry method.NLFEM analysis is carried out for both initially deflected model after eigenvalue buckling analysis and naturally deflected model after welding operations. The comparative ultimate strength results are quite consistent, and this shows that the digital photogrammetric modelling method can be used in the analysis of ship structural elements.

Noise Imitation Based Adversarial Training for Robust Multimodal Sentiment Analysis

As an inevitable phenomenon in real-world applications, data imperfection has emerged as one of the most critical challenges for multimodal sentiment analysis. However, existing approaches tend to overly focus on a specific type of imperfection, leading to performance degradation in real-world scenarios where multiple types of noise exist simultaneously. In this work, we formulate the imperfection with the modality feature missing at the training period and propose the noise intimation based adversarial training framework to improve the robustness against various potential imperfections at the inference period. Specifically, the proposed method first uses temporal feature erasing as the augmentation for noisy instances construction and exploits the modality interactions through the self-attention mechanism to learn multimodal representation for original-noisy instance pairs. Then, based on paired intermediate representation, a novel adversarial training strategy with semantic reconstruction supervision is proposed to learn unified joint representation between noisy and perfect data. For experiments, the proposed method is first verified with the modality feature missing, the same type of imperfection as the training period, and shows impressive performance. Moreover, we show that our approach is capable of achieving outstanding results for other types of imperfection, including modality missing, automation speech recognition error and attacks on text, highlighting the generalizability of our model. Finally, we conduct case studies on general additive distribution, which introduce background noise and blur into raw video clips, further revealing the capability of our proposed method for real-world applications.

Finite Elements modelling and assessment of ceramic rollers with edge cracks

To ensure reliability of hybrid cylindrical roller bearings each ceramic roller is inspected, and scrapped if a surface imperfection above the critical size is detected. This inspection aims to reduce the potential root cause of Rolling Contact Fatigue (RCF) which can occur during operation, shortening the bearing life. The rejection criterion is based on experimental and theoretical knowledge, which for the last decade was developed in SKF for the material imperfections mainly located on the rolling element raceway. These imperfections are subjected to high contact pressure and therefore are considered as the primary root cause of RCF failure. Regarding rollers, however, imperfections can be present beyond the raceway, i.e. at the roller chamfer where the lower risk of RCF is expected, because the edge imperfections are typically out of the rolling contact zone. Nevertheless, the risk associated with these features should be assessed too, chiefly because the size of edge imperfections can be rather large. In our previous study, the imperfection termed as a Missing Material was studied, combining the semi-analytical tool for the contact mechanics and the Finite Elements (FE) method for the stress analysis. In the current work, another imperfection type is considered, and this is a surface crack located at the chamfer of ceramic roller. The RCF analysis is based on the semi-analytical evaluation of the rolling contact pressure (between a ceramic roller and a steel inner ring), and computational fracture mechanics for the estimation of fatigue crack propagation.

A unified buckling formulation for linear and nonlinear analysis of laminated plates using penalty based [formula omitted] FEM-HSDT model

In this paper, the effect of pre-buckling boundary conditions and the type of nonlinearity for stress stiffening used in different linear and nonlinear buckling approaches is studied for laminated composite plates. The study is conducted using a C0 finite element (FE) plate model, employing a unified C1 higher-order shear deformation theory (HSDT). The set of governing equations is derived using the principle of virtual displacement and solved using the tangent-based arc-length method in conjunction with a simple branch switching technique. The performance of the present C0 FE model is assessed through a validation exercise and comparison with results obtained via the use of ANSYS and, for linear analysis, Navier solution, as well as solutions available in the literature. The influence of the different in-plane loads, boundary conditions, side-to-thickness ratio, fiber orientation, types of imperfection and penalty stiffness matrix are also examined. The results show that the same boundary conditions must be utilized in both pre-buckling and linear eigenvalue analyses for accurate and realistic predictions of critical buckling loads, as confirmed from the nonlinear buckling analyses. Furthermore, the critical buckling loads obtained using Green–Lagrange nonlinearity are observed to be more conservative than those obtained using von Kármán nonlinearity. The nonlinear buckling approach is a generalized approach while the nonlinear eigenvalue approach has a limited range of application.

Fatigue strength of cruciform joints with weld imperfections: A comprehensive numerical study

The paper presents an investigation into the fatigue resistance of load-carrying cruciform joints that exhibit weld imperfections. To accomplish this, a finite-element model of the joint is validated by a comparison to experimental investigations. The model includes both a global and a submodel that integrates the effective notch stress concept into its design. This enables the simulation of various types of weld imperfections, such as lack of penetration, lack of root fusion, undercut, excessive convexity, incorrect weld toe, excessive asymmetry of fillet welds and linear misalignment, to assess their impact on the fatigue strength of the cruciform joint. The analysis reveals that these imperfections lead to an increase in stress at the notches of the cruciform joint, which can be characterized as a function of the joint's geometrical properties. Global geometry influences on the fatigue strength of different cruciform join geometries can be regarded independently from the influence of the weld imperfections that is given by stress concentration factors. The normalised stress concentration factor enables a comparison between imperfection influences and shows, that the notch-softer design with full penetration welding at the cruciform joint is in a relative relation more strongly influenced by imperfections than the design with fillet welds. Also, the undercut represents the imperfection with the strongest effect in a relative relation within the sizes considered.Being able to evaluate the fatigue strength values of steel components with weld imperfections eliminates the need for costly repairs and new fabrications, which would otherwise result in a loss of resources and economic efficiency.

Equivalent geometric imperfection for interaction buckling of welded box-section columns - Stochastic analysis

The current paper investigates recently developed GMNIA-based equivalent global and local imperfections to be applicable in the FEM-based design of welded box-section columns. While these imperfections were developed independently for the local and global buckling problems, their applicability to coupled instability problems has not yet been investigated. Therefore, this study addresses this gap by investigating the effectiveness of these imperfections in predicting pure local, global and interaction buckling capacities by comparing them against accurate stochastic analyses using Monte Carlo simulations. The current simulations take into account the variations in geometrical and material properties as well as the imperfections, leading to a highly accurate estimation of the buckling capacity of welded box-section columns. Statistical measures are used to assess the accuracy of each imperfection type and imperfection combination. The discrepancy in deterministic resistance resulting from the application of imperfections and combinations is assessed by comparing them with the accurate buckling resistance. Based on the statistical evaluation, the numerical model uncertainty is also evaluated, serving as the input data of the model factor calculation. The present paper gives a unique introduction to the calculated model factors and presents its calculation methodology for local and global buckling problems.

An Enhanced YOLOv5-Based Algorithm for Metal Surface Defect Detection

The detection of surface defects in metal materials has been a challenging issue in the industrial domain. The existing algorithms for metal surface defect detection are limited to a few specific types of defects and exhibit low performance with detection of defects of varying scales. A novel detection method based on the Information Enhancement YOLOv5 Network (IE-YOLOv5) for surface defects in metal parts is proposed, to realize efficient detection, which introduces a lightweight Federated Fusion Slim Neck module (FF-Slim-Neck) and a Parameter-free Spatial Attention mechanism (PSA) in YOLOv5 network. Comparative experiments were conducted using the NEU-DET dataset. The experimental results indicate that the proposed algorithm for detecting defects on metal surfaces achieves an average precision of 96.7% when identifying six different types of surface imperfections: crazing, inclusions, patches, pitting, scaling, and scratches. This represents a 2.4% enhancement in precision compared to the YOLOv5 algorithm. The measured processing velocity of this approach stands at 46.17 frames per second (FPS), highlighting its remarkable qualities of resilience, precision, and real-time capability.

Imperfections in realistic metal wind turbine support towers: a one‐at‐a‐time (OAAT) study

AbstractThe ultimate limit state of buckling is an important consideration for the design of wind turbine support towers (WTSTs) which is increasingly being done with the aid of advanced nonlinear finite element analysis according to EN 1993‐1‐6. As these towers are relatively slender thin‐walled metal shell structures, their response and buckling resistance is invariably affected by geometric imperfections. This paper presents a sensitivity study into the possible relative influences of four different types of realistic imperfections that are likely to arise in WTST construction on the elastic‐plastic buckling resistance as assessed by computational GMNIAs. These include idealised but realistic representations of axisymmetric circumferential weld depressions, unintended eccentricities at curved plate boundaries, a global out‐of‐roundness and corrected parallel flange interface gaps. The relative sensitivity is explored via a ‘one‐at‐a‐time’ (OAAT) study where all factors but one are kept at a constant intensity while the active factor is scaled, with the influence on the computed GMNIA under two load cases recorded. The OAAT study suggests that for shell structures representative of the geometric ranges typical for WTSTs, the weld depression has the most deleterious effect on the predicted buckling resistance.