scholarly journals Model-based analysis of constructional steel structures exemplified by dimensional checking on railway car shells using 3D scanning

2020 ◽  
Vol 9 (1) ◽  
pp. 109-116
Author(s):  
Uwe Jurdeczka
Keyword(s):  
Steel Structure ◽  
Steel Structures ◽  
Constructional Steel ◽  
Rail Vehicles ◽  
Comprehensive Information ◽  
Inspection Process ◽  
3D Scanners ◽  
Actual Configuration ◽  
Difference Images ◽  
Model Based Analysis

Abstract. The analysis of constructional steel structures (such as car shells for rail vehicles) in terms of dimensional checking according to DIN 25043-2:2012 (presented here) and completeness checking (investigated in Jurdeczka, 2017) represents a challenge because of the dimensions of the test object (20m×3m×3m) and because of the number of mounted parts (several hundred). As presented here and in former publications, the use of 3D scanners allows us to obtain sufficiently comprehensive information about the actual configuration (dimensions and completeness) of the constructional steel structure to be checked. By using an adapted algorithm, the respective 3D model as the target state is superimposed with difference images. These difference images show possible dimensional deviations as well as possible missing parts or, at the least, suspect points. For dimensional checking, there are advantages in the inspection process. In addition, a detailed image can be obtained, which can be used for later evaluations.

scholarly journals Concept for completeness checking of joined structures exemplified on rail vehicle car body shells

2017 ◽  
Vol 6 (1) ◽  
pp. 53-63
Author(s):  
Uwe Jurdeczka
Keyword(s):  
Steel Structure ◽  
Steel Structures ◽  
Point Clouds ◽  
Constructional Steel ◽  
Car Body ◽  
Target State ◽  
Beam Geometry ◽  
The Difference ◽  
Actual Configuration ◽  
D Model

Abstract. Completeness checking of constructional steel structures with several hundred weld-on parts (mountings, such as car body shells/chassis for rail vehicles, for example) still represents a great challenge. It has been performed manually so far. By the use of 3-D scanners, it is possible to obtain sufficiently comprehensive information about the actual configuration (as-is state) of the constructional steel structure to be checked. For this purpose, the laser beam geometry must be contemplated. By using an adapted algorithm for post-processing of the resulting point clouds, difference figures are superimposed over the respective 3-D model as the target state. Therefore, an algorithm was adapted and applied here. The difference figures are useful for signalling the possible deviations and the missing parts, at least, however, suspect points. Thus, the disadvantages of the exclusively manual completeness checking practiced so far, i.e. tiredness and slowness of the inspector, can largely be avoided. The 3-D model-based inspection procedure allows one to handle the variation in the target state with just a few volumes of equal configuration (e.g. less than 10 trains with equal configuration). There is a general problem that the tolerance for the structure is in the same range as the size of the mountings. It is possible to solve this problem by dividing the test item as well as the point cloud into areas. Superposing the 3-D model by point clouds and calculating the difference figures will be performed area by area.

Dynamic Characteristics of Base-Isolated Steel Frame under Seismic Ground Motion

2011 ◽  
Vol 255-260 ◽  
pp. 2341-2344
Author(s):  
Mohammad Saeed Masoomi ◽  
Siti Aminah Osman ◽  
Ali Jahanshahi
Keyword(s):  
Ground Motion ◽  
Base Isolation ◽  
Time History ◽  
Steel Structure ◽  
Steel Structures ◽  
Steel Frame ◽  
Nonlinear Time History Analysis ◽  
Seismic Load ◽  
Vector Method ◽  
Seismic Ground Motion

This paper presents the performance of base-isolated steel structures under the seismic load. The main goals of this study are to evaluate the effectiveness of base isolation systems for steel structures against earthquake loads; to verify the modal analysis of steel frame compared with the hand calculation results; and development of a simulating method for base-isolated structure’s responses. Two models were considered in this study, one a steel structure with base-isolated and the other without base-isolated system. The nonlinear time-history analysis of both structures under El Centro 1940 seismic ground motion was used based on finite element method through SAP2000. The mentioned frames were analyzed by Eigenvalue method for linear analysis and Ritz-vector method for nonlinear analysis. Simulation results were presented as time-acceleration graphs for each story, period and frequency of both structures for the first three modes.

scholarly journals Experimental study on fatigue performance of Q420qD high-performance steel cross joint in complex environment

2021 ◽  
Author(s):  
Haigen Cheng ◽  
Cong Hu ◽  
Yong Jiang
Keyword(s):  
Fatigue Life ◽  
High Performance ◽  
Steel Structure ◽  
Steel Structures ◽  
Fatigue Tests ◽  
Fatigue Performance ◽  
Corrosive Media ◽  
Joint Connection ◽  
High Performance Steel ◽  
The Cross

AbstractThe steel structure under the action of alternating load for a long time is prone to fatigue failure and affects the safety of the engineering structure. For steel structures in complex environments such as corrosive media and fires, the remaining fatigue life is more difficult to predict theoretically. To this end, the article carried out fatigue tests on Q420qD high-performance steel cross joints under three different working conditions, established a 95% survival rate $$S{ - }N$$ S - N curves, and analyzed the effects of corrosive media and high fire temperatures on its fatigue performance. And refer to the current specifications to evaluate its fatigue performance. The results show that the fatigue performance of the cross joint connection is reduced under the influence of corrosive medium, and the fatigue performance of the cross joint connection is improved under the high temperature of fire. When the number of cycles is more than 200,000 times, the design curves of EN code, GBJ code, and GB code can better predict the fatigue life of cross joints without treatment, only corrosion treatment, and corrosion and fire treatment, and all have sufficient safety reserve.

scholarly journals A New Approach for Cylindrical Steel Structure Deformation Monitoring by Dense Point Clouds

2021 ◽  
Vol 13 (12) ◽  
pp. 2263
Author(s):  
Dongfeng Jia ◽  
Weiping Zhang ◽  
Yuhao Wang ◽  
Yanping Liu
Keyword(s):  
Steel Structure ◽  
Steel Structures ◽  
Point Clouds ◽  
Deformation Monitoring ◽  
Deformation Analysis ◽  
Relative Deformation ◽  
Structure Deformation ◽  
Single Time ◽  
Cylindrical Steel ◽  
Cylinder Fitting

As fundamental load-bearing parts, the cylindrical steel structures of transmission towers relate to the stability of the main structures in terms of topological relation and performance. Therefore, the periodic monitoring of a cylindrical steel structure is necessary to maintain the safety and stability of existing structures in energy transmission. Most studies on deformation analysis are still focused on the process of identifying discrepancies in the state of a structure by observing it at different times, yet relative deformation analysis based on the data acquired in single time has not been investigated effectively. In this study, the piecewise cylinder fitting method is presented to fit the point clouds collected at a single time to compute the relative inclination of a cylindrical steel structure. The standard deviation is adopted as a measure to evaluate the degree of structure deformation. Meanwhile, the inclination rate of each section is compared with the conventional method on the basis of the piecewise cylinder fitting parameters. The validity and accuracy of the algorithm are verified by real transmission tower point cloud data. Experimental results show that the piecewise cylinder fitting algorithm proposed in this research can meet the accuracy requirements of cylindrical steel structure deformation analysis and has high application value in the field of structure deformation monitoring.

A Framework to Support the Optimization of Modularized Oil and Gas Structures

2018 ◽  
Author(s):  
Vincenzo Castorani ◽  
Paolo Cicconi ◽  
Michele Germani ◽  
Sergio Bondi ◽  
Maria Grazia Marronaro ◽  
...  
Keyword(s):  
Lead Time ◽  
Oil And Gas ◽  
Steel Structure ◽  
Steel Structures ◽  
Modular System ◽  
Test Case ◽  
Plant Design ◽  
Conceptual Study ◽  
A Current ◽  
Gas Plants

Modularization is a current issue in the context of plant design. A modular system aims to reduce lead time and cost in design phases. An oil & gas plant consists of many Engineered-To-Order solutions to be submitted and approved during the negotiation phase. In this context, design tools and methods are necessary to support the design life cycle from the conceptual study to the detailed project. The paper proposes an approach to optimize the design of modularized oil & gas plants with a focus on the related steel structures. A test case shows the configuration workflow applied to a modular steel structure of about 400 tons. The modularized layout has been optimized using genetic algorithms. A Knowledge Base has been described to support the configuration phase related to the conceptual design. Design rules and metrics have been formalized from the analysis of past solutions.

Solar Concentrating Systems Using Small Mirror Arrays

2009 ◽  
Vol 132 (1) ◽  
Author(s):  
Joachim Göttsche ◽  
Bernhard Hoffschmidt ◽  
Stefan Schmitz ◽  
Markus Sauerborn ◽  
Reiner Buck ◽  
...  
Keyword(s):  
Power Plants ◽  
Raw Materials ◽  
Large Fraction ◽  
Steel Structure ◽  
Steel Structures ◽  
Cost Effective ◽  
Wind Loads ◽  
Drive Systems ◽  
Mirror Area ◽  
The Cost

The cost of solar tower power plants is dominated by the heliostat field making up roughly 50% of investment costs. Classical heliostat design is dominated by mirrors brought into position by steel structures and drives that guarantee high accuracies under wind loads and thermal stress situations. A large fraction of costs is caused by the stiffness requirements of the steel structure, typically resulting in ∼20 kg/m2 steel per mirror area. The typical cost figure of heliostats (figure mentioned by Solucar at Solar Paces Conference, Seville, 2006) is currently in the area of 150 €/m2 caused by the increasing price of the necessary raw materials. An interesting option to reduce costs lies in a heliostat design where all moving parts are protected from wind loads. In this way, drives and mechanical layout may be kept less robust, thereby reducing material input and costs. In order to keep the heliostat at an appropriate size, small mirrors (around 10×10 cm2) have to be used, which are placed in a box with a transparent cover. Innovative drive systems are developed in order to obtain a cost-effective design. A 0.5×0.5 m2 demonstration unit will be constructed. Tests of the unit are carried out with a high-precision artificial sun unit that imitates the sun’s path with an accuracy of less than 0.5 mrad and creates a beam of parallel light with a divergence of less than 4 mrad.

scholarly journals Experimental Study on the Behavior of Tension Member Under Rupture

2021 ◽  
Keyword(s):  
Experimental Study ◽  
Tensile Force ◽  
Steel Structure ◽  
Steel Structures ◽  
Structural Members ◽  
Steel Members ◽  
Tension Member ◽  
Strong Relation ◽  
Almost All ◽  
Tension Members

Abstract. A steel structure is naturally lighter than a comparable concrete construction because of the higher strength and firmness of steel. Nowadays, the growth of steel structures in India is enormous. There are so many advantages in adopting the steel as structural members. Almost all high-rise buildings, warehouses & go-downs are steel structures and even some of the commercial buildings are made of steel. Tension members are the elements that are subjected to direct axial load which tends in the elongation of the structural members. Even today bolted connections play a major role in the connection of hot rolled structural steel members. In this experimental study the behavior of tension members (TM) such as plates, angles & channels have been studied under axial tensile force. There is strong relation between pitch and gauge (with in the specified limit as per IS 800:2007) in determining the rupture failure plane. In this study we intensively tested the behaviour of TM for different fasteners pattern by changing the pitch, gauge, end & edge distance and by adopting the different patterns or arrangements of bolted connection in it.

scholarly journals Mechanical Behavior of Damaged H-Section Steel Structure

2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Xibing Hu ◽  
Rui Chen ◽  
Yuxuan Xiang ◽  
Yafang Chen ◽  
Qingshan Li
Keyword(s):  
Cross Sections ◽  
Elastic Moduli ◽  
Mechanical Test ◽  
Steel Structure ◽  
Steel Structures ◽  
Computational Accuracy ◽  
Cross Sectional ◽  
Steel Columns ◽  
Steel Members ◽  
The Cross

Steel structures are usually damaged by disasters. According to the influence law of the damage on the elastic modulus of steel obtained by the mechanical test of damaged steel, the average elastic moduli of H-section steel members were analyzed. The equations for calculating the average elastic moduli of damaged H-section steel members at different damage degrees were obtained. By using the analytical cross-sectional method, the cross-sectional M-Φ-P relationships and the dimensionless parameter equations of the H-sections in the full-sectional elastic distribution, single-sided plastic distribution, and double-sided plastic distribution were derived. On the basis of the cross-sectional M-Φ-P relationships and dimensionless parameters of actual steel members, the approximate calculation equations for the damaged cross sections were obtained. The Newmark method was used to analyze the deformation of damaged steel columns. Analytical results show good agreement with the test results. The equations and methods proposed in this study have high computational accuracy, and these can be applied to the cross-sectional M-Φ-P relationships and deformation calculation of damaged steel members.

scholarly journals Structural Analysis of Steel Structures under Fire Loading

10.14311/1083 ◽  
2009 ◽  
Vol 49 (1) ◽  
Author(s):  
C. Crosti
Keyword(s):  
Finite Element ◽  
Structural Analysis ◽  
Steel Structure ◽  
Steel Structures ◽  
Global Behavior ◽  
Fire Load ◽  
Stiffness Reduction ◽  
Fire Loading ◽  
The Right ◽  
Real Building

This paper focuses on the structural analysis of a steel structure under fire loading. In this framework, the objective is to highlight the importance of the right choice of analyses to develop, and of the finite element codes able to model the resistance and stiffness reduction due to the temperature increase. In addition, the evaluation of the structural collapse under fire load of a real building is considered, paying attention to the global behavior of the structure itself. 

scholarly journals Effects of Surrounding Earth on Shell During the Construction of Flexible Bridge Structures

2019 ◽  
Vol 41 (2) ◽  
pp. 67-73
Author(s):  
Czesław Machelski
Keyword(s):  
Steel Structure ◽  
Steel Structures ◽  
Static Condition ◽  
Steel Bridge ◽  
Interfacial Interactions ◽  
Soil Medium ◽  
Bridge Structures ◽  
Internal Forces ◽  
Bearing Loads ◽  
Corrugated Plates

AbstractA characteristic feature of soil-steel structures is that, unlike in typical bridges, the backfill and the carriageway pavement with its foundation play a major role in bearing loads. In the soil-steel structure model, one can distinguish two structural subsystems: the shell made of corrugated plates and the backfill with the pavement layers. The interactions between the subsystems are modelled as interfacial interactions, that is, forces normal and tangent to the surface of the shell. This is a static condition of the consistency of mutual interactions between the surrounding earth and the shell, considering that slip can arise at the interface between the subsystems. This paper presents an algorithm for determining the internal forces in the shell on the basis of the unit strains in the corrugated plates, and subsequently, the interfacial interactions. The effects of loads arising during the construction of a soil-steel bridge when, for example, construction machines drive over the structure, are taken into account in the analysis of the internal forces in the shell and in the surrounding earth. During construction, the forces in the shell are usually many times greater than the ones generated by service loads. Thus, the analytical results presented in this paper provide the basis for predicting the behaviour of the soil medium under operational loads.

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