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Steel Construction Published the List of Highly Influential Articles of 2020
2026 Vol. 41, No. 4
Display Method:
2026, 41(4): 1-9.
doi: 10.13206/j.gjgS25062402
Abstract
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Abstract:
To investigate the fatigue performance of orthotropic steel bridge decks with open ribs in coastal areas， fracture mechanics analysis and finite element simulation were employed. Focusing on the deck-T rib weld detail， this study adopted a simplified corrosion model. The ABAQUS and FRANC3D software tools were combined to examine the distribution patterns of stress intensity factor amplitudes throughout the entire crack propagation process， including crack initiation within the corrosion pit， crossing over the pit edge， and propagation outside the pit. This study simulated the propagation paths， morphologies， and rates of initial cracks under different corrosion states. Furthermore， it analyzed the influence of varying deck thicknesses and corrosion pit sizes on the fatigue performance of the deck-T rib details in a corrosive environment. The results indicated that the influence of corrosion pits on the stress intensity factor amplitude at the crack tip exhibited distinct stages. The effect was most severe when the crack was inside the pit or had just crossed over the pit edge. During this brief period， the stress intensity factor amplitude at the ends of the crack front increased sharply to 2.96 times the original amplitude. Once the crack moved away from the pit， the influence rapidly diminished. The fatigue life of the corroded model was significantly lower than that of the uncorroded model. When the crack propagated to the critical size （half the deck thickness）， the fatigue life of the 50-year corroded model （3.403 million cycles） was only about 51% of the uncorroded model’s life （6.660 million cycles）. The life of the corroded model （3.689 million cycles） when the crack reached a depth of 8 mm was also significantly lower than that of the uncorroded model when it reached the critical depth， indicating that corrosion markedly accelerated crack growth rates. Increasing the deck thickness substantially improved fatigue performance. When the deck thickness increased from 12 mm to 20 mm， the fatigue life to reach the critical crack size increased dramatically by 1866.5%， and the average crack propagation life increased by 968.6%. This strongly demonstrated that increasing deck thickness effectively reduced stress levels at the weld and was the most effective structural measure for enhancing fatigue resistance. The detrimental effect of corrosion on fatigue life was primarily concentrated in the initial corrosion stage. When the corrosion duration increased from 0 to 30 years， the critical point fatigue life decreased sharply by 47.1%， and the average crack propagation life decreased by 40.9%. In contrast， when the corrosion duration increased from 30 to 100 years， the critical point fatigue life decreased by only an additional 4.0%， and the average crack propagation life showed a slight increase （+16.5%， which is possibly related to a weakening of stress concentration at the pit in later stages）. This indicated that the presence or absence of corrosion had a significant impact on the crack propagation life of the deck-rib fatigue details， while the duration of corrosion had a relatively minor effect on it.
To investigate the fatigue performance of orthotropic steel bridge decks with open ribs in coastal areas， fracture mechanics analysis and finite element simulation were employed. Focusing on the deck-T rib weld detail， this study adopted a simplified corrosion model. The ABAQUS and FRANC3D software tools were combined to examine the distribution patterns of stress intensity factor amplitudes throughout the entire crack propagation process， including crack initiation within the corrosion pit， crossing over the pit edge， and propagation outside the pit. This study simulated the propagation paths， morphologies， and rates of initial cracks under different corrosion states. Furthermore， it analyzed the influence of varying deck thicknesses and corrosion pit sizes on the fatigue performance of the deck-T rib details in a corrosive environment. The results indicated that the influence of corrosion pits on the stress intensity factor amplitude at the crack tip exhibited distinct stages. The effect was most severe when the crack was inside the pit or had just crossed over the pit edge. During this brief period， the stress intensity factor amplitude at the ends of the crack front increased sharply to 2.96 times the original amplitude. Once the crack moved away from the pit， the influence rapidly diminished. The fatigue life of the corroded model was significantly lower than that of the uncorroded model. When the crack propagated to the critical size （half the deck thickness）， the fatigue life of the 50-year corroded model （3.403 million cycles） was only about 51% of the uncorroded model’s life （6.660 million cycles）. The life of the corroded model （3.689 million cycles） when the crack reached a depth of 8 mm was also significantly lower than that of the uncorroded model when it reached the critical depth， indicating that corrosion markedly accelerated crack growth rates. Increasing the deck thickness substantially improved fatigue performance. When the deck thickness increased from 12 mm to 20 mm， the fatigue life to reach the critical crack size increased dramatically by 1866.5%， and the average crack propagation life increased by 968.6%. This strongly demonstrated that increasing deck thickness effectively reduced stress levels at the weld and was the most effective structural measure for enhancing fatigue resistance. The detrimental effect of corrosion on fatigue life was primarily concentrated in the initial corrosion stage. When the corrosion duration increased from 0 to 30 years， the critical point fatigue life decreased sharply by 47.1%， and the average crack propagation life decreased by 40.9%. In contrast， when the corrosion duration increased from 30 to 100 years， the critical point fatigue life decreased by only an additional 4.0%， and the average crack propagation life showed a slight increase （+16.5%， which is possibly related to a weakening of stress concentration at the pit in later stages）. This indicated that the presence or absence of corrosion had a significant impact on the crack propagation life of the deck-rib fatigue details， while the duration of corrosion had a relatively minor effect on it.
2026, 41(4): 10-18.
doi: 10.13206/j.gjgS25050501
Abstract:
The spatial grid structure is one of the earliest and most widely applied forms of long-span spatial structures. However， as the service life extends， steel members are prone to corrosion-induced damage， leading to cross-sectional loss. This degradation results in decreased structural bearing capacity and stiffness， thereby creating potential safety hazards. Therefore， proposing effective strengthening measures for such structures is of significant importance. In this study， the corroded grid structure of a 57.6 m×28.8 m swimming pool was selected as the research object. Using ABAQUS finite element software， the influence of corrosion on the static performance of the structure was analyzed. A reinforcement scheme involving externally prestressed crossed cable-supported units， which are composed of steel cables， connectors， and struts， was proposed， and its effect on improving the performance of the corroded grid structure was evaluated. The results indicated that corrosion increased the maximum vertical displacement of grid structure joints from 62 mm to 70 mm， representing a relatively small increase. Corrosion showed a limited impact on the overall stiffness of the grid structure. Whether corrosion was considered or not， the maximum deformation of the structure complied with the code requirements. However， due to corrosion and changes in design loads， 14.1% of the members exceeded the stress limits. The adoption of the externally prestressed reinforcement scheme with crossed cable-supported units improved the static performance of the corroded grid structure. The structural stiffness was enhanced to some extent， and the proportion of overstressed members was reduced to 4.5% of the total.
The spatial grid structure is one of the earliest and most widely applied forms of long-span spatial structures. However， as the service life extends， steel members are prone to corrosion-induced damage， leading to cross-sectional loss. This degradation results in decreased structural bearing capacity and stiffness， thereby creating potential safety hazards. Therefore， proposing effective strengthening measures for such structures is of significant importance. In this study， the corroded grid structure of a 57.6 m×28.8 m swimming pool was selected as the research object. Using ABAQUS finite element software， the influence of corrosion on the static performance of the structure was analyzed. A reinforcement scheme involving externally prestressed crossed cable-supported units， which are composed of steel cables， connectors， and struts， was proposed， and its effect on improving the performance of the corroded grid structure was evaluated. The results indicated that corrosion increased the maximum vertical displacement of grid structure joints from 62 mm to 70 mm， representing a relatively small increase. Corrosion showed a limited impact on the overall stiffness of the grid structure. Whether corrosion was considered or not， the maximum deformation of the structure complied with the code requirements. However， due to corrosion and changes in design loads， 14.1% of the members exceeded the stress limits. The adoption of the externally prestressed reinforcement scheme with crossed cable-supported units improved the static performance of the corroded grid structure. The structural stiffness was enhanced to some extent， and the proportion of overstressed members was reduced to 4.5% of the total.
2026, 41(4): 19-29.
doi: 10.13206/j.gjgS25072801
Abstract:
A refined finite element model of the proposed novel internal plug-in self-locking connector for modular steel structures was established in ABAQUS. Tensile and bending tests of the connector were simulated， and the results were compared with experimental data to verify the model’s accuracy. Parametric studies were conducted to investigate the influence of the buckle thickness， the slot side wall thickness， and the slot upper wall thickness on the tensile performance of the connector， as well as the effects of the stiffening rib size， the length of the upper part of the inner plug in the self-locking core， and the thickness ratio （t）of the inner plug to the column on its bending performance. The results indicated that the buckle thickness was the primary controlling factor for the tensile performance of the novel connector. Keeping other dimensions of the inner plug unchanged， increasing the buckle thickness raised the yield load by 20.778%. Increasing the length of the inner plug effectively reduced stress concentration in the modular steel column. Enhancing t improved the bending performance of the connector. Specifically， when the column thickness was 8 mm， increasing t from 1.0 to 1.25 resulted in increases of 1.10% in the yield moment and 2.93% in the ultimate load of the connector. Moreover， increasing the stiffening rib length from 100 mm to 150 mm led to growth of 14.26% in the initial stiffness and 17.87% in the ultimate load， demonstrating that longer stiffening ribs significantly enhanced the connector’s bending capacity.
A refined finite element model of the proposed novel internal plug-in self-locking connector for modular steel structures was established in ABAQUS. Tensile and bending tests of the connector were simulated， and the results were compared with experimental data to verify the model’s accuracy. Parametric studies were conducted to investigate the influence of the buckle thickness， the slot side wall thickness， and the slot upper wall thickness on the tensile performance of the connector， as well as the effects of the stiffening rib size， the length of the upper part of the inner plug in the self-locking core， and the thickness ratio （t）of the inner plug to the column on its bending performance. The results indicated that the buckle thickness was the primary controlling factor for the tensile performance of the novel connector. Keeping other dimensions of the inner plug unchanged， increasing the buckle thickness raised the yield load by 20.778%. Increasing the length of the inner plug effectively reduced stress concentration in the modular steel column. Enhancing t improved the bending performance of the connector. Specifically， when the column thickness was 8 mm， increasing t from 1.0 to 1.25 resulted in increases of 1.10% in the yield moment and 2.93% in the ultimate load of the connector. Moreover， increasing the stiffening rib length from 100 mm to 150 mm led to growth of 14.26% in the initial stiffness and 17.87% in the ultimate load， demonstrating that longer stiffening ribs significantly enhanced the connector’s bending capacity.
2026, 41(4): 30-37.
doi: 10.13206/j.gjgS25111002
Abstract:
High-strength self-compacting concrete-filled steel tube is a high-performance composite component formed by filling high-strength self-compacting concrete into steel tubes and adding a high-quality expansion agent. It has become a development trend for large-scale CFST structures. Long-term deformation will aggravate the deformation of vertical members. Owing to the inconsistent deformation of vertical members and the gradual accumulation of such differences， additional internal forces may arise in horizontal members， which may even cause structural tilting and affect the normal service function of the building. However， research on the influence of early-age loading on the long-term performance of high-strength self-compacting concrete-filled steel tubes is very limited. Therefore， in this paper， long-term deformation tests were conducted on 16 circular high-strength self-compacting concrete-filled steel tube short columns， divided into 8 groups. The concrete stress level was 0.3， and the loading duration was 90 days. The effects of concrete strength （C60， C80） and loading age （3 d， 7 d， 14 d， 32 d） on the long-term performance were investigated. Numerical analysis was also performed on high-strength self-compacting concrete-filled steel tubes： based on the modified EC2 shrinkage and creep model for self-compacting concrete with mineral admixtures， the effects of fly ash content and silica fume content on the long-term deformation were analyzed using the step-by-step integration method. The test results showed that the creep of C60 specimens first increased and then decreased with the increase of loading age， while the creep of C80 specimens gradually decreased with the increase of loading age. The parameter analysis results indicated that under single-admixture conditions， the long-term deformation of the members increased with the increase of fly ash content and silica fume content； under composite-admixture conditions， during the late-age loading stage， the long-term deformation decreased with the increase of fly ash content and silica fume content.
High-strength self-compacting concrete-filled steel tube is a high-performance composite component formed by filling high-strength self-compacting concrete into steel tubes and adding a high-quality expansion agent. It has become a development trend for large-scale CFST structures. Long-term deformation will aggravate the deformation of vertical members. Owing to the inconsistent deformation of vertical members and the gradual accumulation of such differences， additional internal forces may arise in horizontal members， which may even cause structural tilting and affect the normal service function of the building. However， research on the influence of early-age loading on the long-term performance of high-strength self-compacting concrete-filled steel tubes is very limited. Therefore， in this paper， long-term deformation tests were conducted on 16 circular high-strength self-compacting concrete-filled steel tube short columns， divided into 8 groups. The concrete stress level was 0.3， and the loading duration was 90 days. The effects of concrete strength （C60， C80） and loading age （3 d， 7 d， 14 d， 32 d） on the long-term performance were investigated. Numerical analysis was also performed on high-strength self-compacting concrete-filled steel tubes： based on the modified EC2 shrinkage and creep model for self-compacting concrete with mineral admixtures， the effects of fly ash content and silica fume content on the long-term deformation were analyzed using the step-by-step integration method. The test results showed that the creep of C60 specimens first increased and then decreased with the increase of loading age， while the creep of C80 specimens gradually decreased with the increase of loading age. The parameter analysis results indicated that under single-admixture conditions， the long-term deformation of the members increased with the increase of fly ash content and silica fume content； under composite-admixture conditions， during the late-age loading stage， the long-term deformation decreased with the increase of fly ash content and silica fume content.
2026, 41(4): 38-47.
doi: 10.13206/j.gjgS25091502
Abstract:
Based on the one-dimensional higher-order beam theory and displacement compatibility conditions， this paper proposed a dynamic modeling method for thin-walled structures with non-rigid connections. By introducing nodal domain displacement compatibility equations and element coupling conditions， a beam-joint coupling model capable of accurately describing section distortion and flexibility effects of joint interfaces was established. This method， through establishing nodal displacement constraint relationships and stiffness integration strategies， achieved efficient characterization of higher-order modal coupling behavior while strictly ensuring kinematic consistency. Numerical examples demonstrated that the proposed model could predict the dynamic response of the structure with significantly better accuracy than traditional beam models： in the vibration analysis of the non-rigid connection structures， the errors in predicting the first nine natural frequencies did not exceed 10% ； in transient response analysis， the results were highly consistent with those of the three-dimensional shell model. Furthermore， the number of elements in this model was only about 1% of that in the shell model， significantly improving computational efficiency， and demonstrating good engineering application value in the conceptual design and parameter optimization stages of light weight thin-walled structures.
Based on the one-dimensional higher-order beam theory and displacement compatibility conditions， this paper proposed a dynamic modeling method for thin-walled structures with non-rigid connections. By introducing nodal domain displacement compatibility equations and element coupling conditions， a beam-joint coupling model capable of accurately describing section distortion and flexibility effects of joint interfaces was established. This method， through establishing nodal displacement constraint relationships and stiffness integration strategies， achieved efficient characterization of higher-order modal coupling behavior while strictly ensuring kinematic consistency. Numerical examples demonstrated that the proposed model could predict the dynamic response of the structure with significantly better accuracy than traditional beam models： in the vibration analysis of the non-rigid connection structures， the errors in predicting the first nine natural frequencies did not exceed 10% ； in transient response analysis， the results were highly consistent with those of the three-dimensional shell model. Furthermore， the number of elements in this model was only about 1% of that in the shell model， significantly improving computational efficiency， and demonstrating good engineering application value in the conceptual design and parameter optimization stages of light weight thin-walled structures.
2026, 41(4): 48-55.
doi: 10.13206/j.gjgS25060901
Abstract:
The roof structure of Wenrui Shanhai Living Room features a complex long-span folded surface. To meet the architectural design requirements and considering factors such as the roof span and support conditions，a structural form combining folded plate trusses， top chord supports，and bottom chord bracing was adopted. This paper introduced the parametric modeling process of this structure， including the calculation and analysis of the static，dynamic，and stability performance of the truss structure，while also considering the interaction between the truss structure and its lower supporting structure. Given the diverse and complex types of truss connection joints，nonlinear finite element software was used to establish solid element models for the analysis of key joints，Additionally，colli- sion detection of the spatial frame was carried out，along with a simulation analysis of the construction process. The analysis results indicate that both the overall structure and joint designs are reasonable，and all performance indicators meet the regulatory require- ments，the segmented installation method construction plan enhances work efficiency while ensuring both construction quality and proj- ect schedule adherence.
The roof structure of Wenrui Shanhai Living Room features a complex long-span folded surface. To meet the architectural design requirements and considering factors such as the roof span and support conditions，a structural form combining folded plate trusses， top chord supports，and bottom chord bracing was adopted. This paper introduced the parametric modeling process of this structure， including the calculation and analysis of the static，dynamic，and stability performance of the truss structure，while also considering the interaction between the truss structure and its lower supporting structure. Given the diverse and complex types of truss connection joints，nonlinear finite element software was used to establish solid element models for the analysis of key joints，Additionally，colli- sion detection of the spatial frame was carried out，along with a simulation analysis of the construction process. The analysis results indicate that both the overall structure and joint designs are reasonable，and all performance indicators meet the regulatory require- ments，the segmented installation method construction plan enhances work efficiency while ensuring both construction quality and proj- ect schedule adherence.
2026, 41(4): 56-68.
doi: 10.13206/j.gjgS25061401
Abstract:
The combined steel support for foundation pits is a planar multi-legged lattice column， and there is a lack of systematic research on its in-plane stability of the imaginary axis. Various local standards and specifications for steel supports issued by different regions have inconsistent provisions for in-plane stability calculation. The formulas in current standards lack a rigorous theoretical basis for the shear effect on lattice columns and the lateral stiffness effect of steel columns， which may lead to unconservative calculation results. Based on a systematic research and analysis of the in-plane stability of lattice combined supports， this study proposed a critical load formula considering shear effects and boundary constraints. The cover plate of the steel support was treated as a deep beam， with its shear deformation effect taken into account. The actual connection between the support and the foundation pit was suggested to be modeled using fixed and simply-supported boundary constraints for calculation. The stabilizing effect of tie rods on the support was analyzed. Under the action of the lateral stiffness K of the steel column， it was found that the lattice column could exhibit multiple high-order instability modes with half-wave characteristics. The shear effect was considered for each mode. Accordingly， a critical load formula incorporating the effect of the steel column was derived. For long supports， two optimization measures and calculation methods for the combined arrangement of rigid columns were proposed.
The combined steel support for foundation pits is a planar multi-legged lattice column， and there is a lack of systematic research on its in-plane stability of the imaginary axis. Various local standards and specifications for steel supports issued by different regions have inconsistent provisions for in-plane stability calculation. The formulas in current standards lack a rigorous theoretical basis for the shear effect on lattice columns and the lateral stiffness effect of steel columns， which may lead to unconservative calculation results. Based on a systematic research and analysis of the in-plane stability of lattice combined supports， this study proposed a critical load formula considering shear effects and boundary constraints. The cover plate of the steel support was treated as a deep beam， with its shear deformation effect taken into account. The actual connection between the support and the foundation pit was suggested to be modeled using fixed and simply-supported boundary constraints for calculation. The stabilizing effect of tie rods on the support was analyzed. Under the action of the lateral stiffness K of the steel column， it was found that the lattice column could exhibit multiple high-order instability modes with half-wave characteristics. The shear effect was considered for each mode. Accordingly， a critical load formula incorporating the effect of the steel column was derived. For long supports， two optimization measures and calculation methods for the combined arrangement of rigid columns were proposed.
2026, 41(4): 69-74.
doi: 10.13206/j.gjgS25021125
Abstract:
This paper proposes a novel method for determining the equivalent moment factor for checking the in-plane stability of beam-columns. The proposed method uses the total second-order bending moment caused by initial deflection and the linearly varied bending moment. By introducing the total bending moment at each position along the member length into the cross-sectional strength formula， a series of axial force-bending moment interaction curves are obtained. The lower-bound envelope of these curves constitutes the final interaction curve for the in-plane stability check. Based on the obtained interaction envelopes， the elastic-plastic equivalent moment factor is derived inversely， and approximate formulas are proposed. Comparisons show that the proposed formulas are in good agreement with the results from the proposed method.
This paper proposes a novel method for determining the equivalent moment factor for checking the in-plane stability of beam-columns. The proposed method uses the total second-order bending moment caused by initial deflection and the linearly varied bending moment. By introducing the total bending moment at each position along the member length into the cross-sectional strength formula， a series of axial force-bending moment interaction curves are obtained. The lower-bound envelope of these curves constitutes the final interaction curve for the in-plane stability check. Based on the obtained interaction envelopes， the elastic-plastic equivalent moment factor is derived inversely， and approximate formulas are proposed. Comparisons show that the proposed formulas are in good agreement with the results from the proposed method.
