Corrugated Steel Webs Research Articles

Mechanical properties of curved composite box girders with corrugated steel webs

Several methods derived for use on traditional concrete curved box girders (CBGs) are used in design practice. However, these typically consider only one elastic modulus and one shear modulus, and consequently cannot be applied directly to CBGs with corrugated steel webs (CSWs) due to the large shear deformations and small longitudinal stiffness of CSWs, while these shear deformations are small and usually ignored for common concrete webs. In this paper, firstly, the flexure-torsion governing differential equations considering the shear deformations and the accordion effect of CSWs, and the distortion governing differential equation considering the accordion effect of CSWs are derived for CBGs with CSWs. A practical method which can solve the deflections, torsional angles, distortional angles, stresses and internal forces of simple and continuous CBGs with intermediate diaphragms is proposed. Secondly, the results of a series of tests performed on three CBGs with CSWs, published test results, as well as finite element analysis results and theoretical results of straight box girders (SBGs) with CSWs are used to verify the correctness of the analytical method. The agreement between analytical, experimental and numerical results is good. Finally, a parametric analysis is conducted and the results show that: (a) the influence of shear deformations of CSWs on the deflections of CBGs with CSWs increases with increasing curvature radius R. For SBGs with CSWs, the deflections may increase by 30% when considering shear deformations. For CBGs with CSWs, the deflection increase ranges between 8% and 30% for concentrated loads depending on the curvature radius. (b) the distortional shear stress, which is small and typically neglected for CBGs with concrete webs, may be as big as, or larger than the flexural shear stress, and must be considered. The restrained torsional shear stress, which is also small and typically neglected for CBGs with concrete webs, can reach 9% of the flexural shear stress, and also must be considered.

Flexural Behavior of Innovative Posttensioned Composite Beams with Corrugated Steel Webs

Steel‐concrete composite beams with corrugated steel webs (CSWs) usually have concrete flanges that are prone to crack under tension, and an innovative posttensioned composite beam (IPCB) with CSWs has been proposed previously to overcome this shortcoming. Here, an IPCB with CSWs is manufactured and submitted to a flexural test to investigate its flexural behavior, based on which finite element (FE) models with different parameters are developed and analyzed using the ANSYS software. The effects of the span‐to‐depth ratio, concrete compressive strength, initial effective prestress, width of the upper concrete flange, and yield strength of the steel tubes on the flexural behavior of the IPCBs with CSWs are discussed. Numerical results show that the span‐to‐depth ratio of the beam and the yield strength of the steel tube have a considerable effect on the ultimate load‐carrying capacity of the IPCB, which increases by 48.2% when the depth of the CSWs is increased from 240 to 400 mm and by 21.8% when the yield strength of the steel tubes is increased from 295 to 395 MPa. The plane‐section assumption is unsuitable for IPCBs. Almost all the unbonded posttensioning strands in the beams yield for the specimens at ultimate state. The normal stress is distributed unevenly across the width of the upper concrete flange, and the maximum shear lag coefficient is 1.17. Based on the numerical results, a calculation method is established to evaluate the bending moment resistance of an IPCB with CSWs. Comparison shows that the theoretical results in accordance with the proposed method agree well with the numerical results.

Experimental research on free vibration of curved composite box-girders with corrugated steel webs

The curved composite box-girders (CBGs) with corrugated steel webs (CSWs) have been used widely in bridges due to their great advantages and the demand of the road alignment, but the curvature makes both the static and dynamic behaviors more complex. To research the free vibration performance of the curved CBGs with CSWs, 5 simply-supported test girders were designed with the span-to-radius ratio (n=L/R), the number of the cells of the box section, and the number of the diaphragms as parameters. The natural frequencies and mode shapes were measured in the experiment. The experimental results were compared with the numerical results using ANSYS software, and a satisfying agreement was obtained. The parametric analysis shows that for the curved CBG with CSWs, the vertical mode shapes are combined flexural and torsion, and the contribution of the torsional effects to the mode shapes and frequencies improve with the increase of n, which leads to a decrease in the vertical and lateral frequencies and increase in the torsional frequency. The corrugated angle of the steel web has little effect on the natural frequencies of the curved CBGs with CSWs. Increasing the thickness of the steel web and the number of the diaphragms can improve the torsional rigidity of the curved CBG with CSWs effectively; while the deck width has a great contribution on the lateral rigidity.

Analysis of Pure Bending Vertical Deflection of Improved Composite Box Girders with Corrugated Steel Webs

Steel bottom plates are applied as replacements for the concrete bottom plates in order to reduce the dead weight of the composite box girders with corrugated steel webs and steel bottom plates (CSWSB). Due to the change in the material, the previous analytical calculation methods of vertical deflection of composite box girders with corrugated steel webs (CSWs) cannot be directly applied to the improved composite box girders. The shear lag warpage displacement function was derived based on the shear deformation laws of the upper flange and the bottom plates of the improved composite box girders. The equations for the calculation of the shear deformation and the additional deflection due to the shear lag of continuous and simply supported composite box girders with CSWSB under concentrated and uniformly distribution loads were derived by considering the double effects of the shear lag and the shear deformations of the top and the bottom plates with different elastic moduli. The analytical solutions of the vertical deflection of the improved composite box girders include the theory of the bending deflection of elementary beams, shear deformation of CSWs, and the additional deflection caused by the shear lag. Based on the theoretical derivation, an analytical solution method was established and the obtained vertical deflection analytical solutions were compared with the finite element method (FEM) calculation results and the experimental values. The analytical equations of vertical deflection under the two supporting conditions and the two load cases have verified the analyses and the comparisons. Further, the additional deflections due to the shear lag and the shear deformation are found to be less than 2% and 34% of the total deflection values, respectively. Moreover, under uniform distributed load conditions, the deflection value was found to be higher than that of the under concentrated load condition. It was also found that the ratio of the deflection caused by the shear lag or the shear deformation to the total deflection decreased gradually with the increase in the span width ratio. When the value of the span width ratio of a single box and single chamber composite box girder with CSWSB was equal to or greater than 8, the deflections caused by the shear lag and the shear deformation could be ignored.

Study on construction control system of continuous rigid frame bridge with corrugated steel webs

In order to improve the management and control level of bridge construction and understand the real-time dynamics of bridge construction in real time, a set of cloud 3D visualization information management and control system is created based on the Internet platform. In view of the characteristics of high precision and great difficulty in the construction control of corrugated steel webs bridge, a set of construction control and control software based on B/S (browser/server) architecture is developed to help managers know the site structure state more intuitionistic and improve the efficiency of construction control and control. The system deeply integrates the two-dimensional plane information with the three-dimensional entity, and realizes the three-dimensional display of information flow by highly restoring the real bridge construction state in the three-dimensional scene. The results show that the system can assist the management personnel to carry out construction management and improve the engineering efficiency through linear prediction. The system can realize the dynamic demonstration of the long span CSW-PC continuous rigid frame bridge 3D model and the graphical display of the construction measurement and control data and progress information.

Finite Element Model Updating for Improved Box Girder Bridges with Corrugated Steel Webs Using the Response Surface Method and Fmincon Algorithm

We propose a practical and fast finite element (FE) model updating method in which the response surface method and fmincon algorithm (FA) are used to modify the FE model of a new, improved box girder bridge with corrugated steel webs. Two three-dimensional FE bridge design models were compared to develop a reasonable initial FE model for updating this bridge. The response surface method (RSM) was used in our method for the optimal experimental design of the updated parameters, which were used as the basis of the numerical analyses performed to obtain the explicit relationships between the structural responses from the FE results and the parameters themselves. A comparison of the two optimisation methods — genetic algorithm and FA — revealed that FA provides more stable optimised results with higher efficiency. Using FA, parameters can be updated by minimising an objective function, which is constructed from residuals between measured and predicted structural responses using the expressed relationships. A numerical example of a simply supported composite girder was discussed to illustrate the effectiveness of our procedure. The method was applied to the FE model updating of the Jingzhong Bridge using in situ static and dynamic results; satisfactory agreement was observed between measured and predicted bridge responses.

Mechanical performance of a beam with corrugated steel webs inspired by the forewing of Allomyrina dichotoma

This study used scanning electron microscopy (SEM) to observe the internal structure of forewings from adult male Allomyrina dichotoma. The images showed that the Allomyrina dichotoma forewing is a composite sandwich structure composed of upper and lower stressed skins, a hollow core layer and an abdominal-wall layer. The core layer has an irregular honeycomb-like structure with columellae; the chitin fibers on the surfaces of these columellae are connected to the upper and lower stressed skins. The structure of corrugated steel web (CSW) bridges is similar to that of a beetle forewing: the top and bottom concrete plates are similar to the upper and lower stressed skins, whereas the CSWs are similar to the irregular thin-walled core layers. In engineering applications, CSWs are prone to buckling. However, beetle forewings have a lightweight, high-strength composite structure that can adapt to complex, variable natural environments and external loads without breaking due to the reinforced columellae inside the structure. Hence, this work studied the microstructure of beetle forewing in an attempt to design a CSW with a columellar structure similar to that found in the core layer of the forewing. Moreover, a finite element model was used to quantitatively analyze the effects of the columellae on the deformation, shear stress distribution and buckling stability of CSW bridges, which can provide a reference for the bionic structure of a beetle forewing and for the optimization of CSW bridges.

Unified calculation formula for predicting the shear stresses in prismatic and non-prismatic beams with corrugated steel webs

The existing shear design theories for hybrid beams with corrugated steel webs (CSWs) used in China and Japan were originally proposed for only prismatic hybrid beams with CSWs. The traditional calculation method assumes that the bending stiffness and axial stiffness of a beam with CSWs are provided by the top and bottom concrete flanges, while the shear stiffness is contributed entirely by the CSWs. However, due to the influence of the Resal effect on a non-prismatic hybrid beam with CSWs, the calculated shear stress of the CSWs will be overpredicted if the shear capacities of the top and bottom concrete flanges are ignored (especially for the case of an inclined bottom flange). These traditional assumptions may no longer be applicable to non-prismatic structural members. Considering the Resal effect and accordion effect of non-prismatic beams with CSWs, this study proposed a practical unified calculation formula suitable for calculating the shear stresses of prismatic and non-prismatic hybrid beams with CSWs. The accuracy and adaptability of this unified calculation formula were verified through prismatic and non-prismatic beam model tests as well as finite element simulations. Moreover, the authors quantitatively discussed the calculation errors of the traditional calculation assumptions for non-prismatic beams with CSWs. In addition, a finite element parameter analysis was performed on a non-prismatic beam with CSWs near the support to clarify the applicable conditions of the unified calculation formula. The numerical results show that when the inclination angle of the bottom flange varies within the range of 0° to 20°, the calculation error of the proposed unified calculation formula is controlled to within 15%, exhibiting good adaptability to changes in the inclination angle. The unified calculation formula can still predict the shear stresses in tapered CSWs with an error of less than 20% when the sum of the thicknesses of the top and bottom concrete flanges does not exceed 20% of the total beam height. It is expected that this study can further develop the shear stress calculation theory for non-prismatic beams with CSWs, thus providing a reference for the reasonable design of tapered CSWs.

Mechanical Characteristic Analysis of Corrugated Steel Webs Using Asynchronous Construction Technology

for application and populization of the corrugated steel web PC composite box-girder bridge, a new asynchronous cantilever construction method was proposed to reflect the social and economic benefits of this type bridge in short term. In this paper, comparisons of the construction process and economic indexes between the traditional hanging basket cantilever construction method and the asynchronous cantilever method. Combination of the large finite element program ANSYS, a fine finite element model of the studied bridge was built, some analysis of the bridge structure were conducted for the whole process of construction, the calculation results were compared with the field testing data by the real-time monitored stress and displacement. The results indicated that the process of asynchronous cantilever construction method is simple and clear, the construction period is short and the economic indicator is high. This proposed asynchronous cantilever construction method is far superior to the traditional hanging basket cantilever construction method. The deformation and stress of structure were varied in a reasonable and safety range during the construction for the proposed method. The structural stress distribution of the proposed method is more reasonable than that of the traditional hanging basket cantilever construction method.

Stress states and shear failure mechanisms of girders with corrugated steel webs

The corrugated steel web girder (CSWG) has been widely used since its light self-weight and high shear stability. Previous studies on the shear response focus on the shear buckling behavior of corrugated steel webs that dominates shear strength of the girder. However, there is a lack of theoretical explanation for this phenomenon. Besides, research on the post-buckling performance of CSGBs is quite limited though that has been observed by several researchers. In this paper, a theoretical approach adopting the rotated stress field method was proposed to analyze stress states in girders with corrugated steel webs under shear and was verified by experimental data. The results could explain the shear strength determined by shear buckling behaviour theoretically. Then, nonlinear finite element analyses were performed on 24 I-beam specimens to investigate the post-buckling performance and ultimate failure mechanisms of the CSWG. The post-buckling performance is provided by a frame system composing the tension zone in the web, the flanges and the stiffeners. When plastic hinges form in the flanges, the girder collapses and the possible collapse mechanisms include the quasi mid-section mechanism, the mid-section mechanism and the girder mechanism. Level of the residual shear strength after buckling and the collapse mechanism are significantly affected by the flange bending stiffness and the web width/height ratio.

Research and Application of Cross Spatial Grid Method in Combined Box Girder Bridge with Corrugated Steel Webs

In order to further study the application of corrugated steel web composite box girder bridge in practical engineering, this paper selects a corrugated steel web box girder bridge with transverse diaphragms as the theoretical model, and uses the cross space grid method to simulate The model. Beam188 is the element type selected for this ANSYS modeling. The longitudinal element of the web is equivalent to a flat plate according to the plate and shell theory. The shape of the vertical element remains unchanged. Under the condition of its own weight, the natural frequency and deflection of the model are compared. The research results show that when the web is divided into whole and separated, the errors of the first-order natural frequencies of the two spatial mesh models and the solid finite element model are both within 10%, and the accuracy of the overall division is higher.

Analysis of continuous PC box girder bridges with CSWs by using equivalent computational model

The widespread usage of prestressed concrete (PC) box girder with corrugated steel webs (CSWs) can be attributed to its many remarkable merits over traditional concrete box girders, such as significantly reducing the deadweight of the girder, speeding up the construction process, avoiding the problem of web cracking and increasing the prestress introduction efficiency. Numerous previous studies were conducted to investigated the mechanical properties of CSWs as well as simply supported box girder bridges with CSWs, whereas very few studies focused on the FE modeling methods of continuous PC box girders with CSWs. In addition, experimental work on scale bridge models or full-scale bridges adopting the box girder with CSWs is very limited. In this paper, an equivalent orthotropic web (EOW) model was developed for CSWs and used to analyze the performance of the continuous PC box girder bridges with CSWs. To verify this model, a one-tenth-scale bridge model was developed for an existing continuous PC box girder bridge with CSWs. Both static and dynamic tests were carried out on this scale bridge model. The results obtained from the bridge finite element (FE) model with EOWs were compared to the results obtained from the bridge FE model with CSWs and also the experimental results from the scale bridge model. Good agreement was achieved between these results, indicating that the EOW model can provide a trustworthy and convenient tool in the FE analysis of PC continuous box girder bridges with CSWs.

A novel asynchronous-pouring-construction technology for prestressed concrete box girder bridges with corrugated steel webs

Owing to the superior mechanical performance and material efficiency, the combination of prestressed concrete (PC) slabs and corrugated steel webs (CSW) as PC girder with CSWs (PCGCSW) is extensively applied to railway and highway bridges. To overcome the shortcomings of traditional balanced cantilever construction (TBCC) of PCGCSW, reduce environmental impact, and promote sustainable construction, a novel asynchronous-pouring-construction (APC) technology is introduced in this paper. This improved method makes full use of the excellent shear capacity of the corrugated steel webs (CSWs) to support the hanging basket, increases the construction platforms to accelerate the construction speed. Based on a practical project of a long-span composite box girder bridge with CSWs in China, the construction process of the APC method is systematically introduced, and the structural safety and environmental sustainability of such bridge using APC technology are evaluated and compared with that using TBCC. The comparison results indicate that APC method can reduce the compressive stress of top concrete slab, but slightly increase the shear stress and deflection during the cantilever construction stage because the hanging basket is directly supported by CSWs. Besides, the weight of the improved handing basket in APC technology is reduced up to half in comparison that in TBCC. Accordingly, the APC technology saves a lot of energy consumption, reduces huge CO2 emissions for construction equipment, and shorts construction period. Therefore, the utilization of APRC technology can ensure the bridge’s safety and reliability, effectively accelerate construction speed, reduce the construction load, decrease the environmental pollution, and save the engineering cost, which can be regarded as a sustainable and environmental-friendly construction method for composite bridges with CSWs.

Modified bar simulation method for shear lag analysis of non-prismatic composite box girders with corrugated steel webs

In this study, a modified bar simulation method is proposed for analyzing the shear lag effect of non-prismatic composite box girders with corrugated steel webs (CBGCSWs) during the elastic stage. In this theoretical method, formulas for the equivalent area of stiffening bar and the shear flow in corrugated steel webs (CSWs) are derived by properly considering the mechanical properties of non-prismatic CBGCSWs. The governing differential equations for shear lag are formulated and solved with given boundary conditions. The feasibility of the proposed method is validated by the finite element (FE) method based on a non-prismatic cantilever beam under different loading conditions. In addition, the shear lag behavior of non-prismatic cantilever CBGCSWs is compared with that of corresponding concrete box girders, and the effects of width-span ratio, girder height ratio, changing curve of girder height and loading form on the shear lag effect of non-prismatic cantilever CBGCSWs are examined based on the modified bar simulation method. Results indicate that non-prismatic cantilever CBGCSWs exhibit more significant shear lag behavior than the corresponding concrete box girders under gravity. The distribution rule of shear flow in concrete flanges, which first increase and then decrease from the cantilever end to the fixed end, causes the transformation between negative and positive shear lag effects in non-prismatic cantilever beams. Increasing the width-span ratio or girder height ratio leads to more serious shear lag effect. The effect of loading form on the shear lag behavior is significant, while the changing curve of girder height has minimal influence.

Computation of Deflections for PC Box Girder Bridges with Corrugated Steel Webs considering the Effects of Shear Lag and Shear Deformation

Prestressed concrete (PC) girders with corrugated steel webs (CSWs) have received considerable attention in the past two decades due to their light self-weight and high prestressing efficiency. Most previous studies were focused on the static behavior of CSWs and simple beams with CSWs. The calculation of deflection is an important part in the static analysis of structures. However, very few studies have been conducted to investigate the deflection of full PC girders or bridges with CSWs and no simple formulas are available for estimating their deflection under static loads. In addition, experimental work on full-scale bridges or scale bridge models with CSWs is very limited. In this paper, a formula for calculating the deflection of PC box girders with CSWs is derived. The longitudinal displacement function of PC box girders with CSWs, which can consider the shear lag effect and shear deformation of CSWs, is first derived. Based on the longitudinal displacement function, the formula for predicting the deflection of PC box girders with CSWs is derived using the variational principle method. The accuracy of the derived formula is verified against experimental results from a scaled bridge model and the finite element analysis results. Parametric studies are also performed, and the influences of shear lag and shear deformation on the deflection of the box girder with CSWs are investigated by considering different width-to-span ratios and different girder heights. The present study provides an effective and efficient tool for determining the deflection of PC box girders with CSWs.

Shear Lag Effect and Accordion Effect on Dynamic Characteristics of Composite Box Girder Bridge with Corrugated Steel Webs

This study proposed a dynamic characteristic analytical method (ANM) of a composite box girder bridge with corrugated steel web (CBGCSW) by completely considering the impact of shear lag effect and accordion effect of corrugated steel webs. Based on energy principles and variational principles, a vibration differential equation and the natural boundary conditions of a CBGCSW were developed. The analytical calculation formula for solving the vibration differential equation was then obtained. The results calculated using the ANM agreed well with previous experimental results, which validated the correctness of ANM. To demonstrate the superiority of the ANM, the vibration frequencies of several abstract CBGCSWs with varying ratios of span–width, obtained using the elementary beam theory (EBT) and the finite element method (FEM), were compared with those obtained by ANM. The efficacy of the ANM was verified and some meaningful conclusions were drawn which are helpful to relevant engineering design, such as the observation that a higher natural vibration frequency and smaller span–width ratio significantly magnified the shear lag effect of CBGCSW. The first five-order natural vibration frequencies of the CBGCSW were significantly lower than those of the composite box girder bridge with general steel web (CBGGSW), which indicates that the impact of the accordion effect is significant.

Influence of bolts on seismic performance of earthquake-resilient prefabricated sinusoidal corrugated web steel beam-column joints

Earthquake-resilient structures have been widely recognized and applied in the seismic field of prefabricated steel structures due to their excellent performance. The prefabricated sinusoidal corrugated web steel beam-column joint (PSCWJ) with the earthquake-resilient design concept has been previously proposed. To study the impact caused by the bolt parameters on the seismic behavior of the new PSCWJ, five specimens were designed, with varying the number of flange connecting bolts, type of bolt holes, and interval between the middle bolts. A low cycle reciprocating load test and the finite element (FE) simulations were conducted on the specimens to determine the failure mode, energy dissipation capacity, ductility, hysteretic curves, sliding curves, strain curves, skeleton curves, and other main indexes on seismic performance. And the study indicates that the PSCWJ has excellent bearing capacity and seismic performance, the new prefabricated joint can realize the dual energy dissipation by buckling and sliding of the flange cover plate (FCP), and the number of flange connecting bolts directly determines the sliding load of FCPs. A rational interval between middle bolts can control the buckling load of FCPs and provide the joint with a satisfactory bearing capacity. The setting of slotted hole can increase the rotation and energy dissipation capacity of the joint. Further, the energy dissipation performance of the repaired specimens is stable under the low frequency constant amplitude loading, thereby ensuring that the PSCWJ can be used as a damper.

Flexural behaviour of segmental prestressed composite beams with corrugated steel webs

An experimental study and theoretical calculations of the flexural behaviour of segmental prestressed composite beams with corrugated steel webs are presented. Four specimens (one monolithic and three segmental beams) are tested. Based on the experiments, the flexural strength of the segmental beams is found to be approximately 0·75 of that of the monolithic beam, and the joint types of CSWs are found to have a little effect on the load-bearing capacity of the segmental beams. Moreover, the load-bearing capacity of the segmental beams is found to maximise by increasing the ratio of internal tendons in the bottom concrete flange to external tendons. Specifically, by increasing the ratio from 2:0:4 to 2:2:2, a 31% increase in the load-bearing capacity has been gained. Additionally, it has been found that the quasi-plane assumption is valid for the segmental beams with CSWs within the elastic range. Finally, a theory-based method for calculating the flexural bearing moment of segmental beams with CSWs is presented by considering the effect of the stress increment of the prestressed tendons.

Mechanical properties analysis of Angle steel connector of composite bridge with corrugated steel webs

The finite element software Midas FEA was used to simulate and calculate the ultimate bearing capacity, von Mises stress and load-slip curves of the Angle steel connector specimen of the composite bridge with corrugated steel webs. And the ultimate bearing capacity obtained by numerical simulation is compared with the calculated value of the bearing capacity of Angle steel connectors in each specification. The results show that when the ultimate bearing capacity of the specimen is reached, most of the Angle steel is in a state of buckling, all the steel bars are in a state of buckling with deformation, and the concrete pin in the hole is partially damaged. In the specifications, the calculation formula of bearing capacity of Angle steel connector is conservative, the main reason is that the influencing factors of ultimate bearing capacity of Angle steel connector are not comprehensive enough, and the existing formula needs to be further revised.

Analysis of Parameter Sensitivity of Construction Control of Multi Span PC Continuous Beam Bridge with Corrugated Steel Webs

In order to study the sensitivity of construction control of multi span PC continuous beam bridge with corrugated steel webs, taking the main bridge of Yesheng Yellow River Highway Bridge in Ningxia as an example, the space finite element analysis software is used to simulate the bridge and calculate the construction control. In the process, different values of the main parameters of the structure affect the degree of the linear and internal stress of the bridge. The calculation results show that the effects of shrinkage and creep of concrete roof and floor, segmental weight and temperature gradient on the deformation and stress of the main beam are obvious; the elastic modulus of the concrete has a certain degree of influence on the deformation and stress of the main beam, and the influence of the prestressing parameters is smaller. Therefore, in the process of construction control, the influence of shrinkage and creep of the concrete roof and floor shall be considered, the weight of the main beam shall be strictly controlled, and the effect of the measurement time and the temperature gradient effect shall be taken into account in the linear monitoring.