Curved Girder Bridge Research Articles

Shear Strength of Trapezoidal Corrugated Steel Webs for Horizontally Curved Girder Bridges

Curved composite girder bridges with corrugated steel webs (CSWs) have already been constructed around the world. However, limited work has been done on their shear behavior. In this paper, the corrugated steel web (CSW) in horizontally curved girders (HCGs) is treated as an orthotropic cylindrical shallow shell, and the analytical formula for the elastic global shear buckling stress is deduced by the Galerkin method. Calculation tables for the global shear buckling coefficient for a four-edge simple support, for a four-edge fixed support, and for the two edges constrained by flanges fixed and the other two edges simply supported are given. Then, a parametric study based on a linear buckling analysis is performed to analyze the effect of the curvature radius and girder span on the shear buckling stress. Analytical and numerical results show that the difference of shear buckling stress of CSWs between curved girders and straight girders is small, so the shear design formulas for straight girders can be applied for curved girders. Finally, a series of tests were performed on three curved box girders with CSWs. Similar to CSWs in straight girders, the shear strain distributions of CSWs in HCGs are almost uniform along the direction of the web height and the principal strain direction angles are close to 45°. For the three specimens, CSWs carry about 76% of the shear force. In the destructive test, shear buckling after yielding occurred in all specimens which is in good agreement with the theoretical prediction, which means that the analytical formulas provide good predictions for the shear buckling stress of CSWs in HCGs and can be recommended for design purposes.

Optimization analysis of external prestressing reinforcement scheme for concrete curved girder bridge

In this paper, the external prestressing method is used to reinforce a prestressed concrete curved girder bridge. The calculation and analysis model of external prestressing reinforcement is established. The alignment of external prestressing tendons and the tension control stress are studied. The reasonable alignment of external prestressing tendons and the parameters of tension control stress are given. The results show that when two steering blocks are set at one-fourth span and three-quarters span to control the alignment and the prestress value outside the curved girder bridge is 25%-35% larger than that inside the bridge, not only the bearing capacity and stiffness requirements can be met, but also the torque produced by the main girder under the external load can be effectively reduced.

Numerical simulation of curved bridge subjected to earthquake induced pounding

Due to the plane geometry of the deck of curved girder bridge, the girder of the bridge will revolve under the excitation of earthquake, leading to impacts between the curved girder and the bridge abutment. In this paper, the3D finite element model of an actual curved girder bridge is established by combining the ABAQUS finite element software with the arbitrary contact search algorithm, and the influence of the impact effect on the seismic response of the curved girder bridge is analyzed. The results show that the impact effect increases the risk of beam falling at the outer corner, and reduces the risk of the axle direction. The impact of non-coaxial contacts on the internal force of the fixed support and the pier under fixed support is greater, and the internal force of the sliding bearing and the bottom of the pier are affected by the sliding direction of the bearing.

Research on Anti-overturning Performance of Multi-span Curved Girder Bridge with Small Radius

Since the severe situation of small radius curved girder overturning accidents in recent years in China, the research of anti-overturning performance with these bridges are becoming more and more important. In this paper, one small radius multi-span curved girder will be studied in the following procedure. Firstly, the requirements and application conditions of anti-overturning analysis methods at present will be summarized. Secondly, the finite element numerical model of the curved bridge will be built and some calculation and research on its anti-overturning performance will be carried out. Furthermore, the valuable conclusion will be drawn too, which can provide powerful practice and theory reference for the application and research of similar structure.

Experimental Study on Torsion Behavior of Concrete Filled Steel Tube Columns subjected to Eccentric Compression

Under gravity and the horizontal earthquake load, the eccentric compression and torsion combined action will be produced in the piers of curved girder bridges and the main arch of arch bridge. In order to study the torsion behavior of concrete filled steel tube columns subjected to eccentric compression, tests were carried out on eight specimens of concrete filled steel tube column subjected to static pure torsion, cyclic pure torsion and eccentric compression-torsion cyclic load. The results of tests have indicated that, the hysteresis curve of concrete filled steel tube column subjected to torsion cyclic load was plump; no pinch phenomenon can be found; the damage and degradation degree of the strength and stiffness of specimens is lower; and high energy dissipation capacity can be achieved. The stiffness degradation of the specimens with square section subjected to eccentric compression-torsion cyclic load is more obvious. The eccentric compression has led to weaken of the energy dissipation capacity of the square section concrete filled steel tube column. Under the ultimate state, the wave angle of steel tube was affected by the eccentric compression.

Structural Performance Evaluation of a Precast PSC Curved Girder Bridge Constructed Using Multi-Tasking Formwork

Recently, advanced transit systems are being constructed to reduce traffic congestions in metropolitan areas. For these projects, curved bridges with various curvatures are required. Many curved bridges in the past were constructed using aesthetically unpleasant straight beams with curved slabs or expensive curved steel box girders with curved slabs. Therefore, many recent studies have been performed to develop less expensive and very safe precast prestressed concrete (PSC) curved girder. One method of reducing the construction cost of a PSC curved girder is to use a reusable formwork that can easily be adjusted to change the curvature and length of a girder. A reusable and curvature/dimension adjustable formwork called Multi-tasking formwork is developed for constructing efficient precast PSC curved girders. With the Multi-tasking formwork, two 40 m precast PSC box girders with different curvatures were constructed to build a two-girder curved bridge for a static flexural test to evaluate its safety and serviceability performance. The static flexural test results showed that the initial cracking load was 1400 kN, exceeding the design cracking load of 450 kN. Also, the code allowed deflection of 50 mm occurred at a load of 1800 kN, verifying the safety and serviceability of the precast PSC curved bridge constructed using the multi-tasking formwork.

Non-linear torsion behaviour of concrete filled steel tube columns

In curved girder bridge and skew bridge structures, due to the inconsistent locations of the mass and stiffness centres, nonlinear torsion effects will be produced in the piers. In order to study the non-linear mechanical behaviour of concrete filled steel tube columns subjected to combined compression–bending–torsion loads, the finite element method, suitable material constitutive equations, boundary conditions and combined load conditions were chosen and applied, and a three-dimensional “solid-shell” model for concrete filled steel tube columns was established. A good agreement was observed between the predicted results and test results, showing that the three-dimensional “solid-shell” model had high solution precisions, and comprehensive results for concrete filled steel tubes subjected to torsion could be obtained. The torsion mechanism of concrete filled steel tube columns was discussed in detail, based on results extracted from finite element models. Finally, a time-history analysis of a curved girder bridge using the finite element model was carried out, and the precision and effectiveness of the three-dimensional “solid-shell” model was fully verified for predicting the deformation and internal force of piers.

Influence of earthquake input angle on seismic response of curved girder bridge

The maximum seismic response of curved bridge is significantly related to the input angle of designated earthquake. Owing to structure irregularities, bridge reactions result from the interaction between the moment and torsion forces. Based on the solving of the seismic response of structure excited by a one-way earthquake input, a uniform expression of the unfavorable angle of the earthquake input was derived, and the corresponding maximum response of structure was determined. Considering the orthotropic and skewed dual-directional earthquake input manners, the most unfavorable angles for the two cases were also derived, respectively. Furthermore, a series finite element models were built to analyze the multi-component seismic responses by examining an example of curved girder bridge considering the variation of curvature radius and the bearings arrangement. The seismic responses of the case bridges, were excited by earthquakes at different input angles, and were calculated and analyzed using a response spectrum method. The input angles of earthquake excitation were progressively increased. From the analysis and comparison based on the calculation results mentioned above, the most unfavorable angle of earthquake excitation corresponding to the maximum seismic response of the curved bridge could be determined. It was shown that the most unfavorable angles of earthquake input resulted from the different response combination methods were essentially coherent.

Influence of secondary torsion on curved steel girder bridges with box and I-girder cross-sections

Steel curved girder bridges are largely used today in motorways and railways. They are often composed of thin-walled crosssections, entirely made of steel or with an upper concrete slab. The deck may have I-girders or box cross-sections: in any case curved girders are subjected to twisting moment, associated with bending, even for dead loads. Moreover, in thin-walled sections the influence of non-uniform torsion becomes sizable with respect to Saint Venant torsion, modifying the state of tangential stresses in the section and introducing axial stresses due to warping being prevented. Open sections of I-girder bridges are especially subject to these phenomena and warping can be significant not only for curved bridges but also for eccentrically applied traffic loads in straight ones. In this paper a method for the evaluation of the effects of non-uniform torsion, based on an energetic approach, is proposed; the method is simple and fast, with a reduced computational burden with respect to finite elements. The solution of curved girder bridges is performed by the Hamiltonian Structural Analysis method, which is implemented for straight and curved girders with thin-walled cross-sections. A parametric analysis is proposed for single and multi-span bridges, with variation in type of loads applied, crosssection parameters, geometric curvature of bridge deck and stiffness ratios of the cross-section. The parametric study is presented through dimensionless diagrams of internal forces for the evaluation of the global behaviour of curved girder bridges together with indications on the stress state of the cross-section. The interpretation of the results of the analyses performed can be useful to designers for the conceptual design stages and for optimization of the geometric and mechanical parameters of I-girder and box girder cross-sections.

Innovative steel bridge girders with tubular flanges

I-shaped steel girders with tubular flanges have been studied for application in highway bridges because of their large torsional stiffness compared to conventional I-shaped steel plate girders (I-girders). For straight girder bridges, the large torsional stiffness of a tubular flange girder (TFG) results in significantly greater lateral–torsional buckling strength compared to a corresponding I-girder. For horizontally curved girder bridges, the large torsional stiffness of a TFG results in much less normal stress, vertical displacement and cross-sectional rotation compared to a corresponding I-girder. The paper presents experimental and finite element analysis results for straight and horizontally curved TFG bridges. The results show the advantages of TFGs in comparison to conventional I-girders. A TFG demonstration bridge constructed in the USA is described.

Research on Working Behavior of Prestressed Curved Girder Bridge

Prestressed curved girder bridge is a important structure type in modem traffic engineering.With the development of economical level and situation of the opening in our country,a large lumber of curved girder bridge have been taken for its favorable linearism and good adjustability in any kinds of ground.This paper illustrates the working behavior of the prestressed curved girder bridge and use ABAQUS to analysis a simple prestressed curved girder bridge.

Study on Simplification Conditions of Curved Regular Bridges under Seismic Effect

A radius of curvature 20 times greater than the deck width of the bridge (R≥20b) is required as a specification in the regular bridge simplification conditions of the seismic response of curved girder bridges. Selecting benchmark bridges and employing parameter analysis method, this article studies on the effect of R/B value of the curved girder bridge on the response ratio of the seismic response calculated using the finite element model and that using a regular girder bridge. This study shows that on conditions that the deck width of the bridge is constant, the smaller the radius of curvature and the larger the B/R value (i.e., the smaller the R/B value) of the curved girder bridge are, the greater the difference between the seismic response of the curved girder bridge and the result calculated with a regular girder bridge is, and the difference is more significant under traverse seismic effect than that of longitudinal seismic effect. On conditions that the radius of curvature is constant, the impact of the change of B/R value due to the deck width change of the bridge on the difference between the seismic response of the curved girder bridge and the result calculated with a regular girder bridge is insignificant. Compared with the deck width of the bridge, the difference between the seismic response of the curved girder bridge and the result calculated with a regular girder bridge is more sensitive to the radius of curvature.

Dynamic Analysis of Curved Box Girder Bridges

Dynamic Analysis of Curved Box Girder Bridges Dr. Ayad A. Abdul Razzak Zeena A. Mohammad Assistant Professor Assistant Lecturer Mosul University/ Civil Engineering Department Abstract A higher order finite strip formulation based on the auxiliary nodal line (A.N.L.) technique for a dynamic analysis of curved box-girder bridges is presented. Newmark’s equations of numerical integration have been applied depending on the values of the coefficients ( , ), and adopted in the current study with a value equal to (0.5, 0.25) of a curved box girder bridge with simple support and exposed to the traffic of the moving vehicles represented by the system of the moving force. Where the dynamic interaction between the vehicle and the bridge is neglected. The study has also required the application of Newmark’s method to find out the dynamic response values represented by (deflections, dynamic amplification factor, Impact factor) to solve the issues related to the bridge loaded by moving vehicles model. Each system is composed of a suspended mass joined with a damper and a spring of stiffness in addition to the unsuspended mass. Keywords: Curved Box Girder Bridges, Dynamic Analysis, Finite Strip. التحليل الديناميكي للجسور الصندوقية المنحنية الدكتور أياد امجد عبد الرزاق زينة عادل محمد أستاذ مساعد مدرس مساعد جامعة الموصل /قسم الهندسة المدنية الخلاصة طبقت طريقة الشريحة المحددة ذات النسق العالي مع تقنية الخط العقدي المساعد لإجراء التحليل الديناميكي التي ) , ( لجسور صندوقية منحنية. واستخدمت طريقة )نيومارك( للتكامل العددي بالاعتماد على قيم المعاملات 5( لج س ر ص ن د و ق ي م ن ح ن بسيط الإسناد المعرضة لمرور .. اعتمدت عليها الدراسة الحالية بقيمة مساوية ل) 5.0 و 0 المركبات المتحركة والمتمثلة بنظام القوة المتحركة ويتم بإهمال الاقتران الديناميكي بين المركبة والجسر. كما تطلبت الدراسة تطبيق طريقة )نيومارك( لإيجاد قيم الاستجابة الديناميكية المتمثلة ب)الإزاحات، عامل التكبير الديناميكي، عامل الصدمة( لحل المسائل المتعلقة بالجسور المحملة بالمركبات المتمثلة بنظام الكتلة المعلقة الذي يأخذ الاقتران الديناميكي بنظر الاعتبار إذ تتألف ك ل م ن ظ و م ة م ن ك ت لة م ع لق ة م ر ت ب ط ة ب م خ م د و ب ن اب ض ج س اء ة ف ض لا ع ن ا لك ت لة غ ي ر ا لم ع لق ة . الكلمات الدالة: الجسور الصندوقية المنحنية، التحليل الديناميكي ، الشريحة المحددة ذات النسق العالي.

Experimental Study on Structural Behavior of Precast PSC Curved Girder Bridge

교통수요의 증가에 따른 교통혼잡을 피하기 위하여 고가도로와 고속도로, 경전철 등이 활발히 건설되고 있으며, 이에 따라 접속부 등과 같은 곡률반경이 작은 곡선교 구간의 발생이 증가하고 있다. 초기에는 직선형의 주형을 연결하여 곡선을 이루는 방법을 사용하였으나, 공사비의 증가와 미관성 측면에서 용이하지 않아 강재를 사용한 곡선주형이 개발되어 적용되고 있다. 강재의 특성상 기하학적인 형상을 구현하는데 상대적으로 손쉽기 때문에 대부분의 곡선교에서는 강재를 이용한 강박스 거더교를 주로 사용하고 있다. 그러나 강박스 거더교는 초기 공사비가 고가이고, 도장과 같은 지속적인 유지관리가 필요한 문제점을 가지고 있다. 최근에는 I형 강재 플레이트 거더를 사용하는 방법이 활발히 연구되고 있으나 곡선 I형상의 특성상 개단면이고 얇은 플레이트를 사용하기 때문에 비틀림 강성이 매우 작아 안전성에 문제가 있는 것으로 지적되고 있다. 이러한 곡선강교의 대안으로 경제성과 안전성이 확보되는 프리캐스트 PSC 곡선거더가 제시되고 있다. 이에 본 연구에서는 프리캐스트 PSC 곡선거더를 효율적으로 제작할 수 있는 스마트 몰드 시스템을 개발하고 이를 적용한 2주형 40m 실물교량의 정적 휨 파괴 실험을 통하여 안전성을 확인하고자 한다. 제작단계에서 단일 거더는 곡률반경에 의해 거더의 전도에 대한 안정성이 문제가 있으나 가로보로 연결된 멀티거더는 하중분배가 적절히 이루어지며 안정성이 확보되는 것으로 나타났다. 정적구조 실험결과에서는 균열하중(1,400 kN)이 설계하중(450 kN)의 약 3배 이상 높은 것으로 나타났으며, 허용처짐량에 해당하는 하중은 설계하중의 4배인 1,800 kN에서 발생하여 사용성과 안전성이 모두 확보되는 것으로 나타났다. Recently, many overpasses, highway, and advanced transit systems have been constructed to distribute the traffic congestion, thus small size of curved bridges with small curvature such as ramp structures have been increasing. Many of early curved bridges had been constructed by using straight beams with curved slabs, but curved steel beams have replaced them due to the cost, aesthetic and the advantage in building the section form and manipulating the curvature of beams, thereby large portion of curved bridges were applied with steel box girders. However, steel box girder bridges needs comparatively high initial costs and continuous maintenance such as repainting, which is the one of the reason for increasing the cost. Moreover, I-type steel plate girder which is being studied by many researchers recently, seem to have problems in stability due to the low torsional stiffness, resulting from the section characteristics with thin plate used for web and open section forms. Therefore, in recent studies, researchers have proposed curved precast PSC girders with low cost and could secured safety which could replace the curved steel girder type bridges. Hence, this study developed a Smart Mold system to manufacture efficient curved precast PSC girders. And by using this mold system a 40 m 2-girder bridge was constructed for a static flexural test, to evaluate the safety and performance under ultimate load. At the manufacturing stage, each single girder showed problems in the stability due to the torsional moment, but after the girders were connected by cross beams and decks, the bridge successfully distributed the stress, thereby the stability was confirmed. The static loading test results show that the initial crack was observed at 1,400 kN when the design load was 450 kN, and the load at the allowable deflection by code was 1,800 kN, which shows that the safety and usability of the curved precast PSC bridge manufactured by Smart Mold system is secured.

Dynamic Response for Collision Load between Over-Height Truck and Curved Beam Bridge

In recent years, ultra-urban road overpass vehicle impact beam incident after another. High beam impact of vehicles on the overpass bridge safety impact has become another important issue. High trucks at home and abroad on the curve of reinforced concrete beam bridge working effect of the impact is still insufficient. Based on high-precision linear dynamic finite element simulation analysis, research under the action of high vehicle collision, reinforced concrete curved girder Bridges of local damage effect and the overall distortion performance. The results showed that: high vehicles on the bridge superstructure imposed impact impulse and punching power led bridge superstructure is hitting zone produce local cracks. Damage caused by different impact velocity varied.

Thermal Load Design Philosophies for Horizontally Curved Girder Bridges with Integral Abutments

A small degree of uncertainty has been observed in determining the significance of thermal loads when designing the superstructure of a horizontally curved steel bridge. This investigation focuses research on a three-span curved bridge with fixed piers and integral abutments. Combining horizontal curvature with increased levels of fixity (e.g., integral abutments and fixed piers) presents a growing concern with regard to the influence of changing temperatures. The purpose of this work was to analytically investigate bridge superstructure behavior under design thermal loading conditions. In doing so, a bridge previously subjected to an empirical field study was modeled using a commercial finite-element analysis software package. The results indicated that thermal stresses in the lower flange of the girder were greatest at the fixed pier locations. These stresses were mostly the result of lateral flange bending caused by the pier restraining lateral movement of the girder. While these stresses were small for this particular bridge, adding only up to 20,684 kPa (3.0 ksi), bridges incorporating integral abutments and fixed piers with increased curvature and skew may require special attention in future practice.

Finite Element Analysis of Influencing Factors of the Spherical Bearing Horizontal Offset in an Interchange Curved Bridge in Beijing

In order to ensure the safety of the curved girder bridge operations, the actual testing is necessary to determine the impact of various factors on the horizontal offset of the bridge bearing against bearing defects. In this paper, finite element analysis with Midas/Civil is applied to each factor separately to get the spherical bearing offset of various factors which compared with the actual displacement analysis, and get the impact the bridge itself gravity, the vehicle load generated by the centrifugal force and the temperature load to the spherical bearing horizontal offset. The analysis results show that the main reason of the spherical bearings horizontal offset is climb shift of the bridge in temperature load. On this account, make effective measures for the protection and repair of bridge to ensure the safety of the bridge operations.

Study on the Static and Dynamic Load Test of Ramp Bridge

Ramp bridges are usually curved girder bridges, and show unique mechanical characteristics under live load. On the basis of an interchange ramp bridge static and dynamic load test in a radius of 230m, the bridges stress, deflection and dynamic characteristics were analyzed and the bearing capacity was evaluated.

Deformation Analysis of Short and Medium Span Curved Beam Bridge

Curved girder bridge can adapt to the complex needs of road, so it applies more and more. Because prestressed curved girder bridge is spatial structure, its deformation under load, prestress etc is very complicated. If ill-considered, it will cause accidents as cracking of beam body, too large transverse displacement and bearing disengaging etc. In this paper, by analysis of engineering examples, using ANSYS finite element analysis software modeling and calculating, we get the deformation law of small and medium span curved girder bridge under deadweight and prestress, and the law has guiding significance and practical value on design.

Under Control

An innovative controlled floating bearing allows thermal movements of a long, severely curved girder bridge yet controls that movement at the expansion joints.