Login
Register
Steel Construction Published the List of Highly Influential Articles of 2020
2025 Vol. 40, No. 3
Display Method:
2025, 40(3): 1-19.
doi: 10.13206/j.gjgS24042201
Abstract
PDF (2441KB)
Abstract:
Nowadays， the main steel structure design codes in various countries （regions） do not cover the design of steel structures using ultra-high-strength structural steel materials with yield strengths exceeding 690 MPa， which limits the engineering applications of such materials. This paper summarized the research achievements of domestic and foreign scholars on ultra-high-strength steel structures from five aspects： materials， residual stress distribution of sections， members， connections and joints， and structural systems. Specifically， it covered the following aspects： static tensile mechanical properties， cyclic constitutive behavior， toughness， and fire resistance of materials； residual stress distribution of sections； mechanical properties of axial compression members， flexural members， and combined compression and bending members； mechanical properties of welded joints， bolted joints， and beam-column connections； relevant design methods for steel structures and structural mechanical properties. The paper also provided prospects for further research on ultra-high-strength steel structures， aiming to provide a reference for the calculation methods and design theories of ultra-high-strength steel materials and promote their applications in the engineering field.
Nowadays， the main steel structure design codes in various countries （regions） do not cover the design of steel structures using ultra-high-strength structural steel materials with yield strengths exceeding 690 MPa， which limits the engineering applications of such materials. This paper summarized the research achievements of domestic and foreign scholars on ultra-high-strength steel structures from five aspects： materials， residual stress distribution of sections， members， connections and joints， and structural systems. Specifically， it covered the following aspects： static tensile mechanical properties， cyclic constitutive behavior， toughness， and fire resistance of materials； residual stress distribution of sections； mechanical properties of axial compression members， flexural members， and combined compression and bending members； mechanical properties of welded joints， bolted joints， and beam-column connections； relevant design methods for steel structures and structural mechanical properties. The paper also provided prospects for further research on ultra-high-strength steel structures， aiming to provide a reference for the calculation methods and design theories of ultra-high-strength steel materials and promote their applications in the engineering field.
2025, 40(3): 20-32.
doi: 10.13206/j.gjgS24032801
Abstract:
To enhance the mechanical properties of existing disassembled modular containerized structures and expand their application in barracks construction， a new structural system for containerized barracks has been developed based on traditional modular steel structure containerized house systems. This system is designed to be suitable for high-speed assembly and disassembly， offering greater flexibility in combination and ensuring floor insulation. The structural system comprises equilateral columns， thin-walled open-section beams， equilateral corner pieces， insulated floor systems， and foundations with adjustable heights. The introduction of this new structural system inevitably leads to changes in mechanical properties， making accurate calculation of structural responses is crucial. Based on the characteristics of disassembled modular container houses， this study employeds nonlinear structural analysis to establish three finite element models： beam element models， shell element models， and multiscale models for single and multi-story containerized units. It thoroughly analyzed the internal forces and deformation responses of components in single and multi-story units， quantified the differences in results caused by assumptions related to beam element models （rigid joints， pin joints） and shell element models （semi-rigidity）， and revealed the load transfer mechanisms resulting from interaction of main-secondary beams and structural configuration. Finally， it clarified the finite element models and refined analysis methods for containerized modular houses， providing valuable references for welding details between main and secondary beams for engineering design.Finite element comparative analysis showed that using beam element model hasd higher computational efficiency， but with lower accuracy of capacity and deformation which fell far short of requirements. The beam element model introduced the plane cross-section assumption automatically during analysis. Deformation results of such model could not reflect the contribution of twisting buckling of cold-formed section to deformation， nor could they reflect the interaction between main and secondary beams. Especially when predicting floor stiffness and deformation， it was not recommended to use beam element models and multiscale models for analysis. Under the "dead load + wind load" load case， the lateral displacement deviation of the multiscale model and the shell element model were marginal. Therefore， when evaluating the lateral displacement response of the structure， the multiscale model could be used for analysis. Multistory modular structural analysis could be carried out by using a hinged-beam element model for analysis， but the results of the beam element model were conservative： under lateral loading， there was a deviation of approximately 30% in deformation， and under vertical loading， there was a deviation of over 50% in internal forces. It was not recommended to use a rigidly connected-beam element model to analyze multistory modular structures， as the results of the rigidly connected-beam element model were comparably unsafe and with larger deviations compared to shell element models.
To enhance the mechanical properties of existing disassembled modular containerized structures and expand their application in barracks construction， a new structural system for containerized barracks has been developed based on traditional modular steel structure containerized house systems. This system is designed to be suitable for high-speed assembly and disassembly， offering greater flexibility in combination and ensuring floor insulation. The structural system comprises equilateral columns， thin-walled open-section beams， equilateral corner pieces， insulated floor systems， and foundations with adjustable heights. The introduction of this new structural system inevitably leads to changes in mechanical properties， making accurate calculation of structural responses is crucial. Based on the characteristics of disassembled modular container houses， this study employeds nonlinear structural analysis to establish three finite element models： beam element models， shell element models， and multiscale models for single and multi-story containerized units. It thoroughly analyzed the internal forces and deformation responses of components in single and multi-story units， quantified the differences in results caused by assumptions related to beam element models （rigid joints， pin joints） and shell element models （semi-rigidity）， and revealed the load transfer mechanisms resulting from interaction of main-secondary beams and structural configuration. Finally， it clarified the finite element models and refined analysis methods for containerized modular houses， providing valuable references for welding details between main and secondary beams for engineering design.Finite element comparative analysis showed that using beam element model hasd higher computational efficiency， but with lower accuracy of capacity and deformation which fell far short of requirements. The beam element model introduced the plane cross-section assumption automatically during analysis. Deformation results of such model could not reflect the contribution of twisting buckling of cold-formed section to deformation， nor could they reflect the interaction between main and secondary beams. Especially when predicting floor stiffness and deformation， it was not recommended to use beam element models and multiscale models for analysis. Under the "dead load + wind load" load case， the lateral displacement deviation of the multiscale model and the shell element model were marginal. Therefore， when evaluating the lateral displacement response of the structure， the multiscale model could be used for analysis. Multistory modular structural analysis could be carried out by using a hinged-beam element model for analysis， but the results of the beam element model were conservative： under lateral loading， there was a deviation of approximately 30% in deformation， and under vertical loading， there was a deviation of over 50% in internal forces. It was not recommended to use a rigidly connected-beam element model to analyze multistory modular structures， as the results of the rigidly connected-beam element model were comparably unsafe and with larger deviations compared to shell element models.
2025, 40(3): 33-38.
doi: 10.13206/j.gjgS23080902
Abstract:
Modular steel building is a new type of prefabricated building structure system. It has become the development trend of building industrialization and has been gradually valued and widely applied in China， because of its advantages of rapid assembly on site and recyclable materials. The inter-module joint has a significant impact on structure performance， and therefore the joint which can take both convenient construction and reliable force transmission into account is one of the key technical difficulties in the widespread application of modular steel buildings. In this study， the research focused on the connection joint between module units of modular steel buildings and especially conducted an in-depth research on the design and analysis of a new type of joint which is adaptable to construction errors， considering the actual situation of construction errors during site construction. By using wedge-shaped blocks in the joint， the new joint can be moderately adjusted in the construction process to ensure the construction convenience and efficiency， while taking into account the mechanical properties of the joint such as tensile properties， compressive bearing capacity and shear resistance. The basic mechanical principles of introducing wedge-shaped blocks to adjust construction errors， the detailed design scheme，calculation method and on-site installation process of the new type of joint were expounded. The advantages and disadvantages of the joint were also analyzed， and another structural form of the joint was given. The new type of joint has the advantages of simple structure， clear force transmission， convenient on-site installation， adaptable to certain construction errors， and can meet the requirements of mechanical bearing capacity， which can be widely used in modular steel buildings.
Modular steel building is a new type of prefabricated building structure system. It has become the development trend of building industrialization and has been gradually valued and widely applied in China， because of its advantages of rapid assembly on site and recyclable materials. The inter-module joint has a significant impact on structure performance， and therefore the joint which can take both convenient construction and reliable force transmission into account is one of the key technical difficulties in the widespread application of modular steel buildings. In this study， the research focused on the connection joint between module units of modular steel buildings and especially conducted an in-depth research on the design and analysis of a new type of joint which is adaptable to construction errors， considering the actual situation of construction errors during site construction. By using wedge-shaped blocks in the joint， the new joint can be moderately adjusted in the construction process to ensure the construction convenience and efficiency， while taking into account the mechanical properties of the joint such as tensile properties， compressive bearing capacity and shear resistance. The basic mechanical principles of introducing wedge-shaped blocks to adjust construction errors， the detailed design scheme，calculation method and on-site installation process of the new type of joint were expounded. The advantages and disadvantages of the joint were also analyzed， and another structural form of the joint was given. The new type of joint has the advantages of simple structure， clear force transmission， convenient on-site installation， adaptable to certain construction errors， and can meet the requirements of mechanical bearing capacity， which can be widely used in modular steel buildings.
2025, 40(3): 39-48.
doi: 10.13206/j.gjgS24080701
Abstract:
Disassembled modular steel structures are characterized by high construction efficiency， economic and environmental benefits， flexibility， and reusability， and have widely used in scenarios such as temporary buildings， emergency response facilities， pandemic hospitals， and military engineering. However， their practical engineering applications face several challenges： 1） The contradiction between standardization and architectural diversity. 2） Unclear force transfer mechanisms exist in commonly used cold-formed open-section primary and secondary beams， with significant discrepancies between assumed and actual boundary conditions at connection joints. 3） Insufficient forms of joints between modular units and external hanging structures. To address these challenges， streamline modular specifications， and improve the mechanical properties， scalability， and application potential of disassembled modular steel structures in barrack construction， a new modular steel camp structure system has been developed based on traditional modular steel housing systems. This new system features efficient assembly and disassembly， flexible unit combinations， and enhanced floor insulation and compatibility with external hanging systems. The system comprises equilateral angle steel columns， equilateral corner fittings， locally reinforced cold-formed open-section primary and secondary beams， an insulated flooring system， an adjustable-height foundation， and external hanging structures. Lateral stiffness and vertical bearing capacity are key metrics for evaluating the mechanical properties of modular steel structures， and the new system introduces significant changes in these properties. Vertical and lateral loading tests were conducted to quantify the stress level at the connections between primary and secondary beams in the top and bottom frames， beam-end stresses， and external hanging structure stresses. Analysis revealed that under standard vertical loads， the overall deformation of the structure was well below standard requirements， demonstrating superior performance. Under lateral loads， the structure showed good lateral stiffness， with recommendations to control fabrication and installation tolerances for improved performance. The deformation characteristics of primary and secondary beams in the top and bottom frames and external structures were studied， complemented by experimental and finite element analysis to evaluate the stress behavior of external joints and foundation components. The results showed that simple hinge or rigid joint assumptions were insufficient to simulate the true mechanical responses of interfaces such as base-to-corner fittings， column-to-corner fittings， and corner-to-corner fittings in the modular steel structures. Refined simulations should account for interface separation characteristics. Additionally， extending secondary beams at least 40 mm into the web of top-frame primary beams could enhance the torsional resistance of primary beams and reduce stress levels at connection joints.
Disassembled modular steel structures are characterized by high construction efficiency， economic and environmental benefits， flexibility， and reusability， and have widely used in scenarios such as temporary buildings， emergency response facilities， pandemic hospitals， and military engineering. However， their practical engineering applications face several challenges： 1） The contradiction between standardization and architectural diversity. 2） Unclear force transfer mechanisms exist in commonly used cold-formed open-section primary and secondary beams， with significant discrepancies between assumed and actual boundary conditions at connection joints. 3） Insufficient forms of joints between modular units and external hanging structures. To address these challenges， streamline modular specifications， and improve the mechanical properties， scalability， and application potential of disassembled modular steel structures in barrack construction， a new modular steel camp structure system has been developed based on traditional modular steel housing systems. This new system features efficient assembly and disassembly， flexible unit combinations， and enhanced floor insulation and compatibility with external hanging systems. The system comprises equilateral angle steel columns， equilateral corner fittings， locally reinforced cold-formed open-section primary and secondary beams， an insulated flooring system， an adjustable-height foundation， and external hanging structures. Lateral stiffness and vertical bearing capacity are key metrics for evaluating the mechanical properties of modular steel structures， and the new system introduces significant changes in these properties. Vertical and lateral loading tests were conducted to quantify the stress level at the connections between primary and secondary beams in the top and bottom frames， beam-end stresses， and external hanging structure stresses. Analysis revealed that under standard vertical loads， the overall deformation of the structure was well below standard requirements， demonstrating superior performance. Under lateral loads， the structure showed good lateral stiffness， with recommendations to control fabrication and installation tolerances for improved performance. The deformation characteristics of primary and secondary beams in the top and bottom frames and external structures were studied， complemented by experimental and finite element analysis to evaluate the stress behavior of external joints and foundation components. The results showed that simple hinge or rigid joint assumptions were insufficient to simulate the true mechanical responses of interfaces such as base-to-corner fittings， column-to-corner fittings， and corner-to-corner fittings in the modular steel structures. Refined simulations should account for interface separation characteristics. Additionally， extending secondary beams at least 40 mm into the web of top-frame primary beams could enhance the torsional resistance of primary beams and reduce stress levels at connection joints.
2025, 40(3): 49-57.
doi: 10.13206/j.gjgS24031702
Abstract:
Based on the analysis models and calculation equations of bending bearing capacity of beam-column joints with T-head Square-neck One-side Bolts （TSOBs）， the expanded parameter analysis was carried out through the Finite Element （FE） numerical simulation method to fill the gap of parameters not considered in the experimental studies and verify the reliability and accuracy of the theoretical analysis models. The results showed that： 1） the three-dimensional FE model of the joints established in the paper could not only accurately predict the failure modes， stress state of each component and yield sequence of the joints under monotone loading， but also obtain the bending moment-rotation relation curves with high consistency with the test results； 2） the error between the theoretical calculation values and the FE values of the bending bearing capacity for the joints was basically within 15%， and only the error of some joints was larger， but not more than 40%. In addition， the peak bearing capacity predicted by the theoretical equation was better than the yield one； 3） for the failure modes， 47.1% of the joints were completely predicted accurately， 47.1% were partially predicted successfully， and only 5.8% of the joints were predicted incorrectly. Considering the complex structure of the joints and the simplification of the analysis models of each component，this degree of prediction error for bending bearing capacity and failure mode should be acceptable.
Based on the analysis models and calculation equations of bending bearing capacity of beam-column joints with T-head Square-neck One-side Bolts （TSOBs）， the expanded parameter analysis was carried out through the Finite Element （FE） numerical simulation method to fill the gap of parameters not considered in the experimental studies and verify the reliability and accuracy of the theoretical analysis models. The results showed that： 1） the three-dimensional FE model of the joints established in the paper could not only accurately predict the failure modes， stress state of each component and yield sequence of the joints under monotone loading， but also obtain the bending moment-rotation relation curves with high consistency with the test results； 2） the error between the theoretical calculation values and the FE values of the bending bearing capacity for the joints was basically within 15%， and only the error of some joints was larger， but not more than 40%. In addition， the peak bearing capacity predicted by the theoretical equation was better than the yield one； 3） for the failure modes， 47.1% of the joints were completely predicted accurately， 47.1% were partially predicted successfully， and only 5.8% of the joints were predicted incorrectly. Considering the complex structure of the joints and the simplification of the analysis models of each component，this degree of prediction error for bending bearing capacity and failure mode should be acceptable.
2025, 40(3): 58-67.
doi: 10.13206/j.gjgS23122903
Abstract:
The prefabricated flat beam adopts prefabricated concrete slabs as the base plates and is laid on the flange plate at the bottom of the steel beam. The steel beam and concrete are combined into a whole through shear connectors and steel trusses. It has the characteristics of high stiffness， high bearing capacity， good fire resistance， convenient construction and low building height， so it has broad application prospects.In order to study the influence of different shear joints on the flexural performance of composite flat beams， a total of three composite flat beam specimens were designed， including capped stud shear joints， transverse reinforcement shear joints and non-shear joints. Flexural loading tests were carried out respectively to analyze the stress process and failure modes of the composite flat beams. The maximum mid-span deflection， ultimate bearing capacity， end slip and strain distribution in mid-span cross-section of the three specimens were compared. In order to further study the influence of different parameters on the maximum deflection and ultimate bearing capacity of the composite flat beam， the finite element numerical simulation of the composite flat beam with the capped connector was carried out by ANSYS software， and the accuracy of the model was verified by the load-deflection curve and crack location.Then， the strengths of steel and concrete， thicknesses of cast-in-place concrete slabs， reinforcement ratio， and thicknesses of steel plates were analyzed.The results showed that the composite flat beam had good integrity， flexural bearing capacity and ductility.The section strain of the flat beam during loading was basically consistent with the assumption of the flat section. The transverse shear joints at the web could effectively reduce the slip between the concrete and the section steel， and improve the flexural stiffness and bearing capacity of the composite flat beam. The finite element simulation results were in good agreement with the experimental results， which showed that the model could simulate the mechanical properties of the composite flat beam. The results of finite element parameter analysis showed： the increase of cast-in-place concrete slab thickness had the most significant effect on the flexural strength of composite flat beams， followed by the increase of concrete and steel strength. The increase of reinforcement ratio had a certain effect on the bearing capacity of the member， and could effectively improve its mechanical properties. Increasing the thickness of flange plates could effectively improve the ultimate bearing capacity of composite flat beams in the condition that the thicknesses of profile plates increased the same.
The prefabricated flat beam adopts prefabricated concrete slabs as the base plates and is laid on the flange plate at the bottom of the steel beam. The steel beam and concrete are combined into a whole through shear connectors and steel trusses. It has the characteristics of high stiffness， high bearing capacity， good fire resistance， convenient construction and low building height， so it has broad application prospects.In order to study the influence of different shear joints on the flexural performance of composite flat beams， a total of three composite flat beam specimens were designed， including capped stud shear joints， transverse reinforcement shear joints and non-shear joints. Flexural loading tests were carried out respectively to analyze the stress process and failure modes of the composite flat beams. The maximum mid-span deflection， ultimate bearing capacity， end slip and strain distribution in mid-span cross-section of the three specimens were compared. In order to further study the influence of different parameters on the maximum deflection and ultimate bearing capacity of the composite flat beam， the finite element numerical simulation of the composite flat beam with the capped connector was carried out by ANSYS software， and the accuracy of the model was verified by the load-deflection curve and crack location.Then， the strengths of steel and concrete， thicknesses of cast-in-place concrete slabs， reinforcement ratio， and thicknesses of steel plates were analyzed.The results showed that the composite flat beam had good integrity， flexural bearing capacity and ductility.The section strain of the flat beam during loading was basically consistent with the assumption of the flat section. The transverse shear joints at the web could effectively reduce the slip between the concrete and the section steel， and improve the flexural stiffness and bearing capacity of the composite flat beam. The finite element simulation results were in good agreement with the experimental results， which showed that the model could simulate the mechanical properties of the composite flat beam. The results of finite element parameter analysis showed： the increase of cast-in-place concrete slab thickness had the most significant effect on the flexural strength of composite flat beams， followed by the increase of concrete and steel strength. The increase of reinforcement ratio had a certain effect on the bearing capacity of the member， and could effectively improve its mechanical properties. Increasing the thickness of flange plates could effectively improve the ultimate bearing capacity of composite flat beams in the condition that the thicknesses of profile plates increased the same.
2025, 40(3): 68-77.
doi: 10.13206/j.gjgS23101603
Abstract:
As an important layout structure for modern urban pipelines， the utility tunnel can not only effectively reduce the difficulty of pipeline operation and maintenance， but also improve the service life and disaster resistance. In order to ensure the destruction-resistance capacity of the city's underground utility tunnel and maintain the normal operation， a new type of air-tight escape door for the utility tunnel has been proposed， which provides protection for the important entrance positions of the utility tunnel. At the same time， numerical simulation methods were used to analyze the displacement， stress， and deformation parameters of the escape door under the impact waves of chemical and nuclear loads. The results indicated that the escape door met the protection requirements， and there was a significant rebound effect under the action of chemical weapons loads. Meanwhile， the maximum rebound displacement mainly depended on the negative pressure in the explosion load. At last， the locking shaft and hinges were the main restraining components of the escape door， which were subjected to complex and concentrated stresses under factors such as shock waves and rebound effects. Therefore， necessary optimization design should be adopted.
As an important layout structure for modern urban pipelines， the utility tunnel can not only effectively reduce the difficulty of pipeline operation and maintenance， but also improve the service life and disaster resistance. In order to ensure the destruction-resistance capacity of the city's underground utility tunnel and maintain the normal operation， a new type of air-tight escape door for the utility tunnel has been proposed， which provides protection for the important entrance positions of the utility tunnel. At the same time， numerical simulation methods were used to analyze the displacement， stress， and deformation parameters of the escape door under the impact waves of chemical and nuclear loads. The results indicated that the escape door met the protection requirements， and there was a significant rebound effect under the action of chemical weapons loads. Meanwhile， the maximum rebound displacement mainly depended on the negative pressure in the explosion load. At last， the locking shaft and hinges were the main restraining components of the escape door， which were subjected to complex and concentrated stresses under factors such as shock waves and rebound effects. Therefore， necessary optimization design should be adopted.
2025, 40(3): 78-84.
doi: 10.13206/j.gjgS23120603
Abstract:
The steel box girder structure of the offshore bridge is subject to the coupling effect of marine corrosion and vehicle cyclic load at the same time， and in the long-term service process， both seawater corrosion or wheel load-induced deformations， it will have a certain impact on the stability capacity of the U-rib stiffened. In order to study the mechanism of the degradation of the stability capacity of the U-rib stiffened plate of the cross-sea steel box girder during long-term operation， this paper takes the compressive U-rib stiffener member of the steel box girder roof as the research object， and used the ABAQUS finite element software to establish the finite element model of the U-rib stiffened plate to analyze the influence of the coupling effect of the bending deformation and wheel loads of the member in the corrosive environment on the stability capacity of the U-rib stiffened plate. The results showed that for the U-rib stiffened plate with different wheel load ratios， the bearing capacity gradually decreased with the increase of load ratios in the same corrosion period， and the maximum reduction was 5.27%. Under the same overload ratio， with the increase of corrosion duration， the bearing capacity was reduced， and when the overload ratio with the largest degree of reduction was 4， the corrosion duration wad 100 years， which was 9.12% lower than that of the same overload size and non-corroded components， and the size of the wheel load and the corrosion effect of seawater had a certain impact on the stability capacity of the U-rib stiffened plate. In the operation process of the bridge， due to the effect of the structural dead weight and the wheel load， the bridge deck showed different degrees of plastic deformation， so that the force of the U-rib member is no longer a complete axial compressive force， but an eccentric force， when the bending amplitude was L/500， L/250， the ultimate stability capacity of the component was reduced by 9.03% and 19.16% respectively compared with the bending member with the amplitude of L/1000 The increase of bending amplitude reduced the ultimate stability capacity of the component， thereby accelerating the process of reaching the stability capacity of the component， but did not change the failure mode of the component. When the operation time reached 100 years， the ultimate stability capacity of the component considering the coupling action of corrosion loads and deformations decreased by 18.65% compared to its inital states（0 h）. Under the same circumstances， the ultimate stability capacity considering only corrosion and the coupling action of corrosion and load decreased by 8.75% and 8.65%， respectively. The influence of deformations caused by single or coupled wheel loads and dead weight on the stability of U-rib stiffened plate members was more significant than corrosion effects.
The steel box girder structure of the offshore bridge is subject to the coupling effect of marine corrosion and vehicle cyclic load at the same time， and in the long-term service process， both seawater corrosion or wheel load-induced deformations， it will have a certain impact on the stability capacity of the U-rib stiffened. In order to study the mechanism of the degradation of the stability capacity of the U-rib stiffened plate of the cross-sea steel box girder during long-term operation， this paper takes the compressive U-rib stiffener member of the steel box girder roof as the research object， and used the ABAQUS finite element software to establish the finite element model of the U-rib stiffened plate to analyze the influence of the coupling effect of the bending deformation and wheel loads of the member in the corrosive environment on the stability capacity of the U-rib stiffened plate. The results showed that for the U-rib stiffened plate with different wheel load ratios， the bearing capacity gradually decreased with the increase of load ratios in the same corrosion period， and the maximum reduction was 5.27%. Under the same overload ratio， with the increase of corrosion duration， the bearing capacity was reduced， and when the overload ratio with the largest degree of reduction was 4， the corrosion duration wad 100 years， which was 9.12% lower than that of the same overload size and non-corroded components， and the size of the wheel load and the corrosion effect of seawater had a certain impact on the stability capacity of the U-rib stiffened plate. In the operation process of the bridge， due to the effect of the structural dead weight and the wheel load， the bridge deck showed different degrees of plastic deformation， so that the force of the U-rib member is no longer a complete axial compressive force， but an eccentric force， when the bending amplitude was L/500， L/250， the ultimate stability capacity of the component was reduced by 9.03% and 19.16% respectively compared with the bending member with the amplitude of L/1000 The increase of bending amplitude reduced the ultimate stability capacity of the component， thereby accelerating the process of reaching the stability capacity of the component， but did not change the failure mode of the component. When the operation time reached 100 years， the ultimate stability capacity of the component considering the coupling action of corrosion loads and deformations decreased by 18.65% compared to its inital states（0 h）. Under the same circumstances， the ultimate stability capacity considering only corrosion and the coupling action of corrosion and load decreased by 8.75% and 8.65%， respectively. The influence of deformations caused by single or coupled wheel loads and dead weight on the stability of U-rib stiffened plate members was more significant than corrosion effects.
2025, 40(3): 85-89.
doi: 10.13206/j.gjgS24051525
Abstract:
Through explanations on the following 4 aspects： 1） a staggered layout of sag-rods in adjacent purlin bays eliminates nearly the axial rigidity of the sag-rod system； 2）the distortional deformation occurred on the sag-rod cross-section changes and increases the normal stresses of purlins， leading to difficulty in predicting the strength of purlins； 3） the lateral deformation of the purlin mostly away from the anchorage point of the sag-rods of the purlin system is very close to the deformation of a purlin without sag-rod； 4） the demand on the rigidity of the sag-rods in a parallel system increases parabolically. The conclusions were drawn that the current layout of sag-rods had little effect on the lateral internal forces， lateral deformation， and bending -torsional stability of purlins. Several suggestions were proposed， including stringent demands for the existing sag-rod system，the use of C sections to provide torsional restraints to purlins， the use of small angles instead of sag-rods at the lower flange of the purlins.
Through explanations on the following 4 aspects： 1） a staggered layout of sag-rods in adjacent purlin bays eliminates nearly the axial rigidity of the sag-rod system； 2）the distortional deformation occurred on the sag-rod cross-section changes and increases the normal stresses of purlins， leading to difficulty in predicting the strength of purlins； 3） the lateral deformation of the purlin mostly away from the anchorage point of the sag-rods of the purlin system is very close to the deformation of a purlin without sag-rod； 4） the demand on the rigidity of the sag-rods in a parallel system increases parabolically. The conclusions were drawn that the current layout of sag-rods had little effect on the lateral internal forces， lateral deformation， and bending -torsional stability of purlins. Several suggestions were proposed， including stringent demands for the existing sag-rod system，the use of C sections to provide torsional restraints to purlins， the use of small angles instead of sag-rods at the lower flange of the purlins.
