Crane Girder Research Articles

Optimisation of Box Girder Design of Overhead Cranes

The subject of the research presented in this article is the dimensional optimisation of the box structure of the main girder for overhead cranes, with the aim to reduce the main girder’s own weight. Described are the applied optimisation methods and also the problems arising during the optimisation process. Loss of shape stability is analysed in more detail, as well as the methods determined for a constructional proposal of the girder cross-section. The developed optimisation procedure is a combination of the calculations, performed in the MS Excel environment, with the simulation of a parametrically modelled girder realised using Dassault Systèmes SolidWorks software v. 2023. Using the example of optimisation of an overhead crane girder with a lifting capacity of 50 tons, the effectiveness of the proposed optimisation procedure is declared, where the existing overhead crane box girder is compared with the optimised cross-section of the box girder.

Treatment of inelastic material models within a dynamic ALE formulation for structures subjected to moving loads

AbstractThis article showcases the development of a dynamic Arbitrary Lagrangian Eulerian (ALE) formulation to account for inelastic material models within a finite element framework. Such a formulation is commonly utilized in research domains like fluid mechanics, fluid‐structure interaction, quasi static remeshing techniques, and quasi static load movement. The work at hand describes the application of the ALE formulation to efficiently analyse structures subjected to moving loads in the field of transient inelastic solid mechanics. In particular, structures such as pavements, gantry crane girders etc., which are subjected to moving loads, can be numerically simulated, and their transient response in the relevant region around the load can be obtained without relying on moving loads. The focus of this article is to facilitate the treatment of history variables stemming from inelastic material models. Of particular interest is the advection procedure required to transport the history variables through the mesh, as the material appears to flow through it. The mathematical framework necessary to treat this advection process is described in detail, considering a nonlinear viscoelastic material model on a neo‐Hookean base at finite deformations. Then, four methods for numerically achieving the advection are implemented within a transient finite element ALE formulation. These methods are compared against each other, and additionally with the conventional Lagrangian method for validation. The results demonstrate satisfactory agreement with conventional simulation methods, while offering a significant improvement in terms of computation speed. With the work at hand, the dynamic response of inelastic materials subjected to moving loads can be numerically simulated in a computationally efficient manner.

Transmission length of multiwire tendon in existing post-tensioned concrete structures

The paper presents unique research on real-scale post-tensioned concrete crane girders dismantled from an existing hall structure. The study aimed to determine the transmission length for bonded prestressing tendons in an anchorage failure situation, a critical factor for proper assessment of the safety of many building structures, mainly those built between the 1950s and 1980s. The results of the tests indicated the feasibility of prestressing force transmission from a 12Ø5 mm Freyssinet-type tendon to the element via bond stress, with implications extendable to the other 18Ø5 mm tendon type prevalent at the time. The key factor affecting transmission efficiency is the quality of tendon duct grouting, with good quality cement injection resulting in transmission length as short as 800 mm. Furthermore, a computational model for the transmission length of prestressing force in post-tensioned concrete members has been developed similarly to the Model Code 2020 for pretensioned concrete. The level I of approximation enables quick transmission length estimation, whereas refined analysis is possible with the level II approach. The developed model and the research findings facilitate a comprehensive assessment of the post-tensioned concrete members in anchorage or tendon failure scenarios. As a result of the analyses carried out, optimal strategies for the further use of the structures can be proposed, fostering a step towards sustainable management.

REPLACEMENT OF THE FLAT WEB OF THE CRANE RUNWAY BEAM WITH A CORRUGATED WEB

This article is devoted to the study of the possibility of replacing a flat web in runway beams with a corrugated one in order to increase the reliability and stability of welded joints. In the study, an analysis of stresses in the structure of two types of web outlines was carried out, the features and advantages of corrugated webs were revealed. The article provides a detailed overview of the analysis results, demonstrating how a corrugated structure can effectively prevent the separation of welds under the influence of loads. The reasons for choosing this method and its practical applicability in industrial conditions are considered in detail. The study involved a computer experiment, including calculations using the Tonus PC SCAD post-processor, as well as the Lira-SAPR 2022 PC. The stages of the experiment include calculations of the geometric characteristics of various web shapes in the Tonus post-processor, modeling of three-dimensional runway crane beams with flat and corrugated webs, calculation and determination of the maximum normal stresses in the web in PC Lira-SAPR 2022, comparison of the results of beams with flat and corrugated webs and interpretation of the results, and substantiation of conclusions based on the data obtained. The authors highlight the prospects for the application of this approach in various fields of industry, emphasizing its importance for ensuring the safety and durability of crane girder structures. The results obtained are the basis for further research and practical implementation of innovative solutions in the design and operation of industrial facilities.

Reasonable design method of box crane girder by Taguchi method

Overhead cranes are widely used in industrial systems. In this study, the research object is the main box girder of the overhead crane. The research objective is to find the parameters to obtain a lighter structure, which reduces the market price of the crane. The article studies the method of calculating crane girders and sets up the optimization algorithm. The study will use the Taguchi method, and ANOVA analysis to evaluate the influence of box girder parameters. The girder weight, stress, local stability, static displacement, and vibration frequency are response values. Constraint conditions are evaluated by examining each factor with response value according to the orthogonal matrix L16. Analysis of the Signal to Noise ratio and ANOVA by Minitab software will select the optimal parameters that satisfy the constraints, the goal is to reduce the volume compared to the original design. The test results of the crane with a lifting capacity of 250 tons, an aperture of 31 m, the girder weight reduced by 24.33 %, while the stress increased by only 6.16 %. The new design ensures suitable local stability conditions by making better use of the material's capabilities. With the new parameters, the technical criteria are guaranteed.

Damage Identification and Health Assessment of Crane Girder Structure Under Moving Loads

In the degradation evaluation process of the crane girder structure under moving loads, the complex vibration response and low accuracy of health index standards are the main factors limiting the performance of the evaluation method. A method for identifying and evaluating damage to crane girder structures under moving loads has been proposed. In this method, optimized empirical wavelet transform (EWT) is used for decomposing the vibration signal of the crane girder structure to obtain sensitive components. A health indicator based on power spectrum maximum sequence is constructed by combining structural vibration simulation and response characteristics analysis under moving loads. A degradation index acquisition scheme based on an optimized sparse autoencoder is proposed, which utilizes a simulated annealing algorithm to optimize the model parameters of the sparse autoencoder. The effectiveness of the proposed method is verified through girder structure crack tests under moving loads.

Причины возникновения усталостных трещин в подкрановых балках мостовых кранов тяжелого режима работы

This article discusses the causes of fatigue cracks in the crane girders of overhead cranes that work with heavy loads, high speeds, and a large number of inclusions within an hour. The main defects and damages of crane beams are shown. As a result of repeated exposure to loads on crane beams, fatigue failures and stress redistribution occur, which can lead to complete destruction. The article focuses on determining the regularity of fatigue crack growth under various material properties and loads, as well as the possibility of using semi-empirical theory. At the end of the article, the ways of changing the fastening of the rail to the crane beam are given as an additional measure when strengthening structures with a reduced resource.

Design of Twin Builder-Based Digital Twin Online Monitoring System for Crane Girders.

The crossbeam is frequently subjected to alternating loads during work as an essential load-bearing part of the crane. However, due to the large volume and the limitations of detection technology, it is impossible to realize online monitoring of the mechanical state. The ongoing advancement of ROMing and digital twin technology plays a pivotal role in facilitating the resolution of this particular issue. In this paper, we take the crane beam as the physical entity and combine the Twin Builder reduced-order technology and Deployer digital twin deployment technology to establish a digital twin of the beam. The load recognition model within the twin system exhibits a prediction error rate of ±5%. Furthermore, the accuracy of the ROM surpasses that of conventional machine learning models by a factor of 25. Upon deployment on the web platform, the results are delivered within 0.5 s, representing a substantial improvement as it is merely 1/15 of the time required for traditional 3D displays. The digital twin online monitoring system has the advantages of high accuracy and low requirements for monitoring equipment, which can be widely used in engineering practice to solve the problem that the mechanical state of large parts cannot be accurately monitored online.

Analysis of Line Balancing using Ranked Positional Weight (RPW), Largest Candidate Rule (LCR), and J-Wagon Methods in Crane Girder Production at PT MHE Demag Surabaya, Indonesia

Every company is required to enhance its quality by implementing improvement actions within the company's production system. PT MHE Demag Surabaya is a company engaged in crane girder manufacturing. This research aims to determine the optimal line balancing using the Helgesson-Birnie/Ranked Positional Weight (RPW) method, the Largest Candidate Rule method, and the J-Wagon method. Line balancing is necessary due to excess operating time in the crane girder manufacturing workstations, which increases the risk of accidents for the workers. The results of data processing which employed these three heuristic methods demonstrate that the RPW method is the most efficient. The Helgesson-Birnie/Ranked Positional Weight (RPW) method yields the most optimal output, with a line efficiency of 96.67%, balanced delay of 3.33%, and total idle time of 4936.8 seconds using 15 workstations. By utilizing the heuristic methods for line balancing, the efficiency decreases to 144.76%, the balanced delay increases to 14.76%, and the total idle time increases to 86,400 seconds.

Numerical simulation research on the overturning of gantry crane by downbursts

Based on the simulation of the fluid-structure interaction response, the cause of an overturning of a gantry crane induced by a downburst in Shenzhen is studied in this paper. According to the results, (1) Vicroy's downburst model could establish the steady-state wind field of the downburst more reasonably when there was only low-level wind speed observation data, and its simulation results were close to the two-dimensional downburst numerical simulation results; (2) Compared with the normal exponential vertical profile of wind speed, the disturbance caused by the front girder of the double-girder gantry crane structure under the downburst wind field was more severe, which increases the probability of the gantry crane overturning. (3) The downwind displacement of the main girder of the gantry crane under the condition of downburst is far greater than that under the normal condition. At the same time, under the condition of downburst, the pressure difference on the surface of the gantry crane was greater, and the distribution of the support reaction force was more uneven, resulting in a stronger overturning tendency of the gantry crane. (4) Under the condition of downburst, the overturning moment and the shearing force borne by the foundation of gantry crane exceeded the critical value to maintain the stability of the gantry crane by the gravity, resulting in the overturning of the gantry crane.

Steel savings in an industrial building column with account for effect of crane girder stiffness

Introduction. Construction science always seeks to save materials, including in the design of steel frameworks. Currently, in modern construction standards, structural analysis of frameworks for industrial buildings, namely their columns, is carried out without considering the stiffness of the crane girder which receives the load from the overhead crane. However, this factor can give a certain economy of metal, since the stiffness of crane structures directly affects the stability of columns of industrial buildings, and therefore the metal consumption of the framework.Aim. To achieve savings of steel due to taking into account the effect of crane girder stiffness on the stability of an industrial building framework.Materials and methods. For these purposes, the authors of the paper used classical methods of structural mechanics. A programmed cyclic algorithm of the Mathcad software was used to find the critical forces and effective length coefficients at various stiffnesses of the column elements. Columns of an industrial building are usually two-member. Given that, its structural design is twice statically indeterminate by the deflection method. The bearing capacity of an industrial building column is found by deriving the critical force, which is determined from the equation obtained by setting equal to zero the stability determinant consisting of the coefficients of the linear equation system by the deflection method. In addition, the effective length coefficient for the upper and lower parts of the column is determined. The paper compares the results obtained with the scheme without taking into account the crane girder.Results. Considering the effect of the crane girder stiffness enabled the material consumption of the column to be reduced by 30 %. Critical forces and effective length coefficients were found at various stiffnesses of the column elements, using a programmed cyclic algorithm of the Mathcad software.Conclusion. Taking into account the stiffness in the structures of the elements in the industrial building frameworks reduces metal consumption.

Study of dynamic response of crane system via surrogates based on Karhunen–Loève expansion and neural networks

Overhead cranes are widely used in construction sites and manufacturing/assembly lines for various tasks (loading, unloading, lifting, transporting,. . . ). This paper investigates the dynamic response of the main beam (i.e., girder) of an overhead crane by a surrogate technique based on truncated Karhunen–Loève (KL) expansion and neural networks. First, the physical modeling and the motion equations of the crane system are derived using the Lagrange equation. Then, the dynamic responses of the overhead crane system with a number of the input parameters (i.e., configurations) are estimated by the numerical Newmark-beta integral method. Finally, the surrogates based on the truncated KL expansion and neural networks are constructed for studying the dynamic responses of the girder within a limited reference dataset. It can be stated that with a convergence property, the reconstructed surrogate performs good predictability for characterizing the dynamic responses of the structure. The presented method allows us to study the dynamic analysis and optimization of the crane according to the design conditions in the actual applications.

Soft-Computing-Based Estimation of a Static Load for an Overhead Crane.

Payload weight detection plays an important role in condition monitoring and automation of cranes. Crane cells and scales are commonly used in industrial practice; however, when their installation to the hoisting equipment is not possible or costly, an alternative solution is to derive information about the load weight indirectly from other sensors. In this paper, a static payload weight is estimated based on the local strain of a crane's girder and the current position of the trolley. Soft-computing-based techniques are used to derive a nonlinear input-output relationship between the measured signals and the estimated payload mass. Data-driven identification is performed using a novel variant of genetic programming named grammar-guided genetic programming with sparse regression, multi-gene genetic programming, and subtractive fuzzy clustering method combined with the least squares algorithm on experimental data obtained from a laboratory overhead crane. A comparative analysis of the methods showed that multi-gene genetic programming and grammar-guided genetic programming with sparse regression performed similarly in terms of accuracy and both performed better than subtractive fuzzy clustering. The novel approach was able to find a more parsimonious model with its direct implantation having a lower execution time.

Light-weight design of an overhead crane’s girder with a non-symmetric box cross-section

The proper choice of material and geometric properties of the girder of the bridge crane can significantly reduce its weight and production cost. This research presents the weight optimization of the main girder with a non-symmetric box-like cross-section. The strength analysis in characteristic points of the critical cross-section and the local stability of plates were conducted using Eurocodes. This study aimed to prove that a proper choice of geometry for the cross-section plates and their additional design elements can have a meaningful impact on the weight. The optimization procedure was done using Water Evaporation Optimization (WEO) algorithm, with the implementation of all necessary criteria and conditions which must be fulfilled. This study revealed that the application of the light-weight design philosophy to the structure of the main girder could significantly reduce its weight, which is verified in the existing examples of double-beam bridge cranes. Achieved savings in girder weight are between 24.43% and 34.73%, dependingly on the considered example. Also, the study showed the influence of the chosen material on the steel girder’s optimum weight and geometric parameters. Depending on the studied example of the bridge crane and selected material, the WEO algorithm gave the same solution through simulations. The value of the optimum weight had a slight deviation at the second decimal place, which is neglectable. The algorithm successfully avoided the trap of getting into the local minimum during the search. In the end, it can be stated that the application of the WEO algorithm was successful in the considered engineering problem since it was the optimization of a complex steel structure with 11 variables and more than 20 constraint functions.

Study on Stress Intensity Factor of the Pit-Crack Model for Portal Crane Girders

In shipbuilding gantry cranes in long-term service in the coastal humid salt-spray environment, the main beam is affected in many places by corrosion fatigue-formed corrosion pits, affecting the structural strength of the main beam. This paper focuses on the impact of corrosion-generated pits under the conditions of crack nucleation. Corrosion fatigue crack nucleation is a local damage evolution process and the stress intensity factor criterion is one of the critical conditions to discern whether a crack sprouts at the corrosion pit. This paper establishes a corrosion pit-crack model based on the overall finite element model of the portal crane, and uses ANSYS software to simulate the stress intensity factor under complex boundary conditions. The results show that the different sizes and depth-to-diameter ratio of the pits greatly affect the value of the stress intensity factor and the stress concentration phenomenon may be the main factor causing the emergence of cracks; the change in the size of the pits on the stress intensity factor is not obvious, but with the increase in the depth-to-diameter ratio of the pits, the stress intensity factor of the pit-crack model is significantly increased. According to the hypothesis of semi-ellipsoidal pitting, the relationship between the stress intensity factor and the stress concentration factor at the pit is proposed, and its calculation results are within 5% error compared with the finite element method, and it is found that the effect of the etch pit on the stress intensity factor is positively correlated with the stress concentration factor; with the increase in the etch pit depth–diameter ratio, the crack budding location changes with the change in the stress concentration location, and the crack is more likely to be generated from the shoulder of the etch pit when the depth–diameter ratio of etch pit exceeds 1.

Coronavirus Mask Protection Algorithm: A New Bio-inspired Optimization Algorithm and Its Applications.

Nowadays, meta-heuristic algorithms are attracting widespread interest in solving high-dimensional nonlinear optimization problems. In this paper, a COVID-19 prevention-inspired bionic optimization algorithm, named Coronavirus Mask Protection Algorithm (CMPA), is proposed based on the virus transmission of COVID-19. The main inspiration for the CMPA originated from human self-protection behavior against COVID-19. In CMPA, the process of infection and immunity consists of three phases, including the infection stage, diffusion stage, and immune stage. Notably, wearing masks correctly and safe social distancing are two essential factors for humans to protect themselves, which are similar to the exploration and exploitation in optimization algorithms. This study simulates the self-protection behavior mathematically and offers an optimization algorithm. The performance of the proposed CMPA is evaluated and compared to other state-of-the-art metaheuristic optimizers using benchmark functions, CEC2020 suite problems, and three truss design problems. The statistical results demonstrate that the CMPA is more competitive among these state-of-the-art algorithms. Further, the CMPA is performed to identify the parameters of the main girder of a gantry crane. Results show that the mass and deflection of the main girder can be improved by 16.44% and 7.49%, respectively.

ФУНКЦИЯ НАДЕЖНОСТИ ПРЕДВАРИТЕЛЬНО НАПРЯЖЕННОЙ КОРРОДИРОВАННОЙ ЖЕЛЕЗОБЕТОННОЙ БАЛКИ ПРИ НЕЛИНЕЙНОМ РАСПРОСТРАНЕНИИ КОРРОЗИИ

The paper considers the limit state function in the context of reliability analysis of corroded beams. Methods for determining the ultimate load limit for corroded beams are discussed. Various approaches to the determination of the limit state function are considered, including those based on statistical data on corrosion and modelling of stresses in a reinforced concrete beam. A general reliability assessment model for reinforced concrete structures should include corrosion propagation. Most previous studies have focused on one-dimensional diffusion problems with an assumed constant corrosion rate. A nonlinear corrosion rate model, unlike linear models, considers the corrosion current density not constant over the service life of a reinforced concrete structure. An approach to reliability analysis together with a nonlinear corrosion growth model is developed. In this paper, the main problems related to reliability under a nonlinear model of prestressed reinforcement rope corrosion of reinforced concrete beams are discussed. A function for the reduction of reinforcing bar diameter from time is presented. Sensitivity analysis is performed to determine the effect of corrosion growth parameters on the reliability index of reinforced concrete T-beam. The nonlinear corrosion growth model, together with other relevant probabilistic models used to describe random variables, was applied to analyze the reliability of a reinforced concrete crane girder. The expression of corrosion current density shows that the corrosion rate increases exponentially as the value of the design parameter of the model increases. To further evaluate the effect of the proposed time corrosion growth model on the reliability of reinforced concrete beam, two specific cases are considered. The first one is with fixed corrosion current density, and the second one is with fixed corrosion growth at a given time.

Defect Detection and Recognition of Crane Girder Structure Based on 3D Reconstruction of UAV

Defect Detection and Recognition of Crane Girder Structure Based on 3D Reconstruction of UAV

Peak Stress Method-Based Fatigue Predictions for Steel Crane Girder Variable-Section Supports

Engineering applications have shown that variable-section supports of steel crane girders are prone to fatigue fracture, and traditional fatigue prediction experience is not applicable to these types of supports due to the complex internal stresses caused by their unique geometries. In this paper, a new fatigue prediction approach was proposed for variable-section supports of steel crane girders based on the peak stress method; this approach can locate the fatigue initiation sites and predict the fatigue lives of variable-section supports under axial and bending loading. Then, some constant-amplitude fatigue test results were presented for typical variable-section supports of steel crane girders. A comparison was made between the experimental results and theoretical estimations using the peak stress method. The results indicated that the peak stress method is appropriate to estimate fatigue life up to crack initiation in variable-section supports of steel crane girders subjected to axial and bending loads.

Container Quay Crane Structural Response under Trolley Traveling

Structural response of quay crane should take more attention with the growth of worldwide logistics demand and quay crane size. This paper analyzes the response mechanism of the metallic structure of the quay crane induced by trolley traveling. An on-site test has been conducted. The time domain of crane girder acceleration signal shows that the main influence of the trolley traveling on crane structure is the high-frequency impact passing through the hinge point. The spectrum shows the main frequency of structure vertical vibration and impact vibration. Single girder model and theoretical derivation reveal that the vertical displacement response is quasistatic. A refined numerical model of the whole crane structure is established. The interaction between the trolley and the girder is realized by S-M contact method. The calculated results are basically consistent with the measured signal. The acceleration result indicates the same information as on-site test such that the structural acceleration response of in-service crane is affected by trolley in high-frequency band. The displacement results in three directions of 10 points on the girder show that the trolley traveling has significant effect on the vertical displacement. The lateral displacement shows the eccentric loading condition of girder. The displacement spectrum indicates that the trolley has little dynamic effect on displacement response of crane structure. The response can be treated as quasistatic.