Experimental study and numerical analysis on mechanical behavior of T-shape stiffened orthotropic steel-concrete composite bridge decks

A new-type of orthotropic steel-concrete composite bridge deck system was developed, by casting the concrete overlay on the top of the orthotropic steel deck ribbed with T-shape steel members. To study its mechanical behavior (in terms of failure mode, load-deflection relationship, concrete crack initiation and propagation, strength, stiffness and so on), two new-type orthotropic steel-concrete composite bridge decks with different section dimensions were experimentally investigated and two reference decks (reinforced concrete deck and orthotropic steel deck) were also involved in the research for comparison. For the two new-type orthotropic steel-concrete composite decks, the average value of ultimate loads per width is 885.7kN, which is 2.35 and 1.61 times of that of the concrete and steel reference decks with almost the same section height. Experimental results proved that the composite deck can effectively control the crack initiation and propagation in the concrete and postpone the yielding of the steel bars and steel plates, due to the composite action between the concrete overlay and the underlying steel plate. Furthermore, the Finite Element (FE) model of the orthotropic steel-concrete composite deck was developed and validated by test results. A parametric study is conducted regarding to the stiffness of shear studs. With the validated FE model, stress distribution in the underlying steel plate and T-shape stiffeners and development of concrete cracking in the concrete overlay were characterized at different load levels.     

State-of-the-art of long-span bridge engineering in China

This paper introduces the state-of-the-art of longspan bridge engineering in China with emphases on recent long-span bridge projects, bridge deck configuration and material, design codes of long-span bridges and improvement of aerodynamic performance. The recent long-span bridge projects include thirty-eight completed suspension bridges, cable-stayed and arch bridges with a main span over 400 m, and eighteen major bridges are under construction. The bridge deck configuration and material, with prestressed concrete decks, steel-concrete composite decks and steel box decks together with several popular cross-sections, are presented. The third part briefly outlines four design codes, including static and dynamic design for highway long-span bridges, and the recent engineering experiences gained from several aerodynamic vibration control projects of long-span bridges are shared in the last part.     

Experimental investigation on behaviour of steel-concrete composite bridge decks with perfobond ribs

This paper introduces a test program conducted for steel-concrete composite bridge decks with perfobond rib shear connectors. The composite deck consists of profiled steel sheeting, perfobond ribs, steel reinforcements, and concrete. To provide longitudinal shear resistance between the profiled sheeting and the concrete, perfobond ribs were used. For a prototype steel-box girder bridge, two types of deck profiles with deck-to-girder connections were designed. To validate the effectiveness of the proposed deck system for bridge application, push-out, full-scale flexural, and deck-to-girder connection tests for each deck profile have been conducted. The results of tests have shown that the perfobond ribs can be effectively used for shear connection in the steel-concrete composite decks.     

新型钢-UHPC组合桥面板抗弯承载力模型试验与理论分析方法

为综合解决正交异性钢桥面板疲劳开裂和桥面铺装易损两大难题,提出一种由波形顶板、超高性能混凝土(ultra-high-performance concrete,UHPC)结构层和改进螺旋线(modified clothoide,MCL)形组合销所构成的新型波形顶板-UHPC组合桥面结构.设计2类共12个足尺模型,对所提出...     

Fatigue evaluation of steel-concrete composite deck in steel truss bridge——A case study

An innovative composite deck system has recently been proposed for improved structural performance. To study the fatigue behavior of a steel-concrete composite bridge deck, we took a newly-constructed rail-cum-road steel truss bridge as a case study. The transverse stress history of the bridge deck near the main truss under the action of a standard fatigue vehicle was calculated using finite element analysis. Due to the fact that fatigue provision remains unavailable in the governing code of highway concrete bridges in China, a preliminary fatigue evaluation was conducted according to the fib Model Code. The results indicate that flexural failure of the bridge deck in the transverse negative bending moment region is the controlling fatigue failure mode. The fatigue life associated with the fatigue fracture of steel reinforcement is 56 years. However, while the top surface of the bridge deck concrete near the truss cracks after just six years, the bridge deck performs with fatigue cracks during most of its design service life. Although fatigue capacity is acceptable under design situations, overloading or understrength may increase its risk of failure. The method presented in this work can be applied to similar bridges for preliminary fatigue assessment.     

面向未来的高性能桥梁结构研发与应用

为从根本上解决混凝土桥、钢桥及钢 混凝土组合桥中的共性技术难题,并提升桥梁结构的性能与品质,笔者团队以超高性能混凝土（UHPC）为基础,研发了面向未来的高性能桥梁结构体系。介绍了笔者团队研发的4类高性能桥梁结构:①钢-超高韧性混凝土（STC）轻型组合桥面结构,其中的STC是钢桥面专用的UHPC;②钢 UHPC华夫板轻型组合桥梁结构;③单向预应力UHPC薄壁连续箱梁结构;④全预制快速架设UHPC城市桥梁结构。通过大量静力和疲劳试验,掌握了各类UHPC桥梁结构的基本受力性能,并建立了计算理论和设计方法。列举了钢 STC轻型组合桥面结构已推广应用于中国的17座钢桥,涵盖了梁桥、拱桥、斜拉桥和悬索桥等各类基本桥型,典型应用包括湖南岳阳洞庭湖二桥等重大工程。到目前为止,各实桥运营状态良好,钢 STC未出现任何病害问题。综合而言,高性能桥梁结构有望突破现有桥梁中的技术瓶颈,具有广阔的应用前景。     

Bending performance of composite bridge deck with T-shaped ribs

This paper proposes a new type of steel-concrete composite deck, which is composed of orthotropic steel deck (OSD) with T-shaped ribs, concrete plate and studs connecting OSD and concrete plate. The OSD can act as framework for concrete plate and contribute to load bearing capacity at the same time, which could save construction time. Compared with conventional OSD system, this new type of composite bridge deck can also improve fatigue performance.ƒConsidering that this type of composite deck is not yet applied in practical engineering and its mechanical performance is not revealed in previous literatures, two full-scale specimens were designed and manufactured in this research. The mechanical performance, particularly, bending capacity in positive and negative region was carefully tested and analyzed. The load-deflection curve, load-slip relation, strain distribution in concrete and steel were obtained. The test results showed that the plastic performance of this kind of composite bridge deck was satisfying and the bending capacity was high.     

组合桥中桥面板结构性能的有限元分析

对局部荷载下,组合桥中桥面板的结构性能进行研究。分析了影响混凝土桥板结构性能的压缩薄膜效应。通过ABAQUS6.5软件,建立非线性3维有限元分析模型。采用一跨组合桥试验数据,验证和校准所提出的有限元模型,进行一系列参数研究,探讨分析结果,提出关于混凝土桥板性能的结论。     

不锈钢复合钢板在铁路钢桥上的应用技术

我国高速铁路钢桥均采用正交异性板钢桥面有碴线路。为提高钢桥面的防腐与使用寿命,合肥铁路枢纽南环线钢桁梁的桥面板采用了具有较高的强度、塑性、韧性、疲劳性能及优良抗腐蚀性能的321-Q345q-D不锈钢复合钢板。针对钢桥面系结构设计特点及制作与安装工艺需要,依据TB10212-2009《铁路钢桥制造规范》、GB/T13148-2008《不锈钢复合钢板焊接技术要求》,对321-Q345q-D不锈钢复合钢板进行焊接工艺试验,其试验结果(数据)均满足设计与施工要求。经对不锈钢复合钢板的钢桥面制作与安装实践,对铁路钢桥推广应用不锈钢复合钢板提出改进建议。     

Finite element investigation of the structural behaviour of deck slabs in composite bridges

This research studies the structural behaviour of bridge deck slabs under static patch loads in steel–concrete composite bridges and investigates compressive membrane action (CMA) in concrete bridge decks slabs, which governs the structural behaviour. A non-linear 3D finite element analysis models was developed using ABAQUS 6.5 software packages. Experimental data from one-span composite bridge structures are used to validate and calibrate the proposed FEM models. A series of parametric studies is conducted. The analysis results are discussed and conclusions on the behaviour of the bridge decks are presented.     

钢板-轻骨料混凝土空心组合板受力性能试验研究

对5块钢板-轻骨料混凝土组合空心组合板试件进行两点对称集中加载静力试验研究,考虑到空心组合板在顺管方向和垂直管向的两个正交方向弯曲刚度比较接近,因此在试验中同时对空心组合板这两个方向的受力性能进行研究,分析了组合板中钢管布置方向、名义剪跨比对其破坏形态和承载能力等受力性能的影响,研究了5块空心组合板的破坏形态、钢板与混凝土应变发展情况、裂缝发展情况、组合板刚度及组合板承载能力。根据试验研究结果,提出了空心组合板承载能力和弯曲刚度计算方法,计算结果与试验结果吻合良好。研究结果表明：空心组合板中钢管可以有效提高组合板承载能力和弯曲刚度;与普通钢板 混凝土组合板相比,钢板-混凝土空心组合板具有自重轻、强度高、刚度大、施工方便和双向受力的性能优势。     

Innovative steel-UHPC composite bridge girders for long-span bridges

Steel and steel-concrete composite girders are two types of girders commonly used for long-span bridges. However, practice has shown that the two types of girders have some drawbacks. For steel girders, the orthotropic steel deck (OSD) is vulnerable to fatigue cracking and the asphalt overlay is susceptible to damage such as rutting and pot holes. While for steel-concrete composite girders, the concrete deck is generally thick and heavy, and the deck is prone to cracking because of its low tensile strength and high creep. Thus, to improve the serviceability and durability of girders for long-span bridges, three new types of steel-UHPC lightweight composite bridge girders are proposed, where UHPC denotes ultra-high performance concrete. The first two types consist of an OSD and a thin UHPC layer while the third type consists of a steel beam and a UHPC waffle deck. Due to excellent mechanical behaviors and impressive durability of UHPC, the steel-UHPC composite girders have the advantages of light weight, high strength, low creep coefficient, low risk of cracking, and excellent durability, making them competitive alternatives for long-span bridges. To date, the proposed steel-UHPC composite girders have been applied to 14 real bridges in China. It is expected that the application of the new steel-UHPC composite girders on long-span bridges will have a promising future.     

钢-混凝土组合结构桥梁研究新进展

钢-混凝土组合结构桥梁近年来在我国得到了迅速的发展。在传统桥梁结构形式的基础上,发展多种新型组合结构桥梁形式,拓宽组合结构桥梁的应用领域。介绍近年来在钢-混凝土组合结构桥梁方面的最新研究进展,内容包括波形钢腹板组合梁桥、槽型钢-混凝土组合梁桥、钢-混凝土组合刚构桥、双重组合作用连续组合梁桥和大跨斜拉桥组合桥面系。通过对传统结构形式的改进和发展,可充分发挥组合结构桥梁的综合优势,研究结果表明,钢-混凝土组合结构桥梁具有广阔的推广应用前景。     

正交异性钢桥面板顶板竖向加劲肋焊接接头疲劳性能试验研究

正交异性钢桥面板的疲劳问题是目前研究的主要热点之一。该文针对国内钢桥面板顶板竖向加劲肋焊接接头的构造细节,通过振动型疲劳试验机开展了18个试件的弯曲疲劳试验,研究了普通角焊缝和熔透角焊缝在不同加载应力幅下的疲劳性能,分析了焊接接头的应力集中系数,并与有限元分析结果进行了对比,得到了普通角焊缝和熔透角焊缝焊接接头疲劳寿命大小;同时采用BS5400、JSSC、Eurocode 3以及我国钢结构设计规范（GB 50017—2003）规定的S-N曲线对试验结果的疲劳强度进行了评定。研究表明：钢桥面板竖向加劲肋焊接接头熔透角焊缝的疲劳性能总体上优于普通角焊缝,对我国钢桥面板竖向加劲肋焊接接头的开裂前的疲劳性能建议采用BS5400-F2的S-N曲线（35MPa）进行设计和评价;并且两者焊接接头的应力集中系数约为2.4左右,其中熔透角焊缝受到焊接工艺的影响其应力集中系数较大,须在焊接后对其进行焊趾表面处理,以进一步提高疲劳性能。     

正交异性钢桥面板的疲劳研究综述

正交异性钢桥面板是国内外大中跨径桥梁普遍采用的桥面结构形式,由于直接承受车轮荷载的反复作用,疲劳问题非常突出。详细阐述正交异性钢桥面板细节构造的疲劳研究概况和相关结论,简述钢桥面板的疲劳评估方法,并对正交异性钢桥面板的疲劳研究进行展望和建议。     

Experimental and analytical study on fatigue behavior of composite truss joints

In order to fully understand the performance of composite joints in a truss bridge with double decks, fatigue tests of three composite joints with different connectors such as headed studs, concrete dowels and perforated plates under constant repeated loading were carried out, and the responses of displacement, strain distribution, crack development, relative slip between concrete and steel were observed after different loading cycles. The experimental results showed that the deflection increased almost linearly with applied load even after certain repeated loading cycles, but the stiffness reduced gradually with the repeated loading cycles. No serious damage occurred except tiny cracks at the steel–concrete interface caused by slip after 2 million repeated loading cycles, which means all three composite joints have good fatigue performance. Based on experimental works, three dimensional finite element models of composite joints were established. The results from finite element analysis were consistent with those from tests in terms of strength and stiffness. Finally, the fatigue details involving reinforcing bars, welding seams and shear connectors were evaluated according to related specifications. The presented overall investigation may provide reference for design and construction of composite joints in composite truss bridges.     

Experiment study on fatigue performance of perforated shear connectors

In order to investigate the fatigue behavior of perforated shear connection in steel-concrete composite bridges, 24 connection specimens with different geometric configurations were subjected to static and fatigue testing protocols. Using the design shear resistance of perforated shear connectors obtained from static push-out tests as a reference load level, numbers of fatigue cycles under different cyclic load levels were determined. Accumulated relative slip between steel and concrete components was used to characterize and track fatigue damage accumulation. The relationship between cycle numbers and accumulated relative slip between steel and concrete was established. Test results revealed that the fatigue damage of perforated shear connectors can be divided into three stages, and fatigue life of perforated shear connectors can be evaluated by the accumulated slip, which depends on the maximum shear stress and stress range.     

波形钢腹板PC箱梁桥的施工技术与效益分析

波形钢腹板PC箱梁桥是一种较先进的钢-混凝土组合梁桥,在国内外得到了广泛应用.针对国内外对波形钢腹板箱梁的研究及应用现状,综合介绍了波形钢腹板PC箱梁桥的施工特点、结构优点、发展概况.较为深入地分析了其主要施工特点与方法,波形钢腹板PC箱梁桥的受力特点和施工工艺,波形钢腹板PC箱梁桥的经济效益,并对波形钢腹板的经济效益与普通PC箱梁桥的作了对比分析.     

钢 超薄UHPC轻型组合桥面短钢筋连接件#br# 抗剪性能研究

为解决钢-超薄UHPC轻型组合桥面板由于UHPC层过薄而难以采用常规剪力连接件的问题,提出一种新型剪力连接件 短钢筋连接件。通过静力推出试验以及疲劳推出试验对短钢筋连接件的抗剪性能进行初步研究。静力推出试验结果表明：①该试验存在焊缝剪断和UHPC局部破坏(短钢筋拔出)两种破坏模式;②短钢筋连接件承载力随着焊缝长度增加而提高;③短钢筋连接件抗剪承载力高于栓钉,略低于钢筋网焊接件。疲劳推出试验结果表明：80MPa剪应力幅下,3个试件疲劳寿命分别为194.2、271.0、195.8万次,去掉最大值,剩余两者平均疲劳寿命为195万次,略低于规范相应的200万次。通过Miner-Palmgren线性累积损伤理论对不同应力幅下的疲劳次数转化,可得200万次疲劳下的剪应力幅为79.6MPa。仿真结果表明：在纵横向间距200mm×200mm布置方式下,两类疲劳细节(连接件位置与钢顶板位置)均能够满足抗剪疲劳设计要求。文章研究成果可为今后实桥应用提供理论依据。     

钢板-轻骨料混凝土空心组合板弯曲刚度计算方法研究

钢板-轻骨料混凝土组合板是由底部平钢板和上部轻骨料混凝土通过开孔钢板穿入空心钢管焊接而成的新型组合板形式,具有良好的受力性能和广泛的应用前景.为了研究钢板-轻骨料混凝土空心组合板的弯曲刚度和变形计算方法,对5块钢板-轻骨料混凝土空心组合板试件进行两点对称集中加载静力试验研究,得到该空心组合板在静力作用下的跨中弯矩-挠度...