Teruhiko Yoda

Analysis, design and construction of curved composite girder bridges: State-of-the-art

The horizontally curved composite girder bridges have excellent properties, such as quick construction, good seismic performance, saving construction formwork and convenience in spatial arrangement.etc, which have greatly promoted the application of such bridges. The objective of this paper is to provide and summarize important references related to the analysis, design and construction of curved composite girder bridges. Subjects discussed in this review include (1) different curved girder bridge configurations and their applied range; (2) current specifications; (3) construction issues; (4) design methods; (5) analytical methods; (6) load distribution; (7) torsional behavior; (8) warping stresses; (9) stability; (10) ultimate load-carrying capacity; (11) dynamic and seismic response; (12) loading test; (13) long-term behavior; and (14) design details. The literature survey presented herein mainly focuses on papers written in English, Japanese and Chinese in relation to curved composite girders.

Trends in steel-concrete composite bridges in Japan

This paper presents trends in new types of steel-concrete composite bridge decks and piers in Japan, and focuses mainly on composite girders, slabs, and columns. Since 1953, many simple supported composite bridges were built in Japan, but this type of bridge has been built less often during the last two decades. Continuous composite girder bridges show a similar tendency. All continuous bridges constructed since 1973 have been non-prestressed. To increase the durability and load-carrying capacity of bridge slabs, and shorten construction times, various types of slabs for composite girders have been developed, mainly for simple span bridges. Composite girder bridges, using prestressed precast concrete slabs, have been developed recently in Japan. Other types of composite girder bridges include those with a corrugated steel web plate and external cables. The use of steel-concrete composite decks is likely to increase, due to the rapid deterioration of ordinary reinforced concrete slabs for highway bridges. Composite decks in Japan are generally partially precast, and are mainly steel plate-concrete slab composite or concrete-filled steel grillage composite. Applicable bridge types for composite columns are discussed briefly, and the mathematical theory of their strength and ductility is outlined.

Experimental and numerical study on cyclic behaviour of steel beam-to-column joints

Ten specimens are tested to investigate the cyclic behavior of beam-to-column joints of steel frames with joint panels. The performances of the joints with respect to strength, rigidity, and hysteretic performance are examined. Three different load-carrying mechanisms can be identified. Panel resistance ratio (Rp) is presented for predicting the buckling patterns. The validity ofRp is confirmed through the present experimental results. On the basis of the experimental results of steel beam-to-column moment joints, 3-D nonlinear finite element models are established to analyze the mechanical properties of these connections. The load-displacement curves of the finite element analysis are in good agreement with those of the tests in terms of strength and unloading stiffness. A shear lag phenomenon was captured in the beam flanges by not only experimental results but also numerical analysis. Parametric studies are conducted on the connections under monotonic loading to investigate the influences of connection dimension, resistance ratio on the connection behavior. It was found that the failure modes are influenced by the resistance ratio, while the thickness of joint panels resulting in large effects on the strength and stiffness under shear failure mode.

Effects of Bridge Accessories in Steel–Concrete Composite Railway Bridges in Service Condition

Abstract Bridge accessories, such as parapets, service ducts, and track slabs, are commonly used in railway bridges, but their real effects on the structural behavior of the bridges are still unknown because very few studies have been reported on this significant aspect. In engineering practice, lack of information on the contribution of bridge accessories may cause problems for bridge design, bridge health evaluation and monitoring, bridge management and operation, and bridge maintenance. Given this background, field tests were performed on a railway bridge with typical bridge accessories to confirm their contribution to bridge rigidity (or stiffness), as well as their effects on the sectional normal strain distribution. Both displacements in the midspan and strain results on key sections were measured in the field test and reported in this paper. Based on the field test observations, a numerical model capable of simulating the present railway bridge was built and was used to investigate the effects of t...

Identification of bifurcation points occurring on the mechanism paths of deployable structures

This paper is concerned with the identification of bifurcation points occurring on the mechanism paths of a linkage, in which the structural system consists of links and revolute joints. The way that the links are assembled is mathematically described by compatibility conditions. The present paper mainly deals with the kinematic paths of mechanism that goes through special configurations of kinematic bifurcations. In general, such special configurations are called uncertainty configurations or singular configurations. The Jacobian derived from the compatibility conditions has been used as a measure of the distance away from the singular configurations. The Jacobian does not always give sufficient results for the detection of bifurcation points. This suggests that it is necessary to consider higher-order infinitesimals for examining approximate solutions of compatibility conditions. The Hessian matrix derived from the Jacobi matrix is considered to be one of the promising measure and may clarify the nature of the singular configuration as to whether the system is at a bifurcation point or not. In this paper, the theory behind the kinematic bifurcation of mechanisms of a linkage is explained and the numerical analysis of illustrative examples is discussed in detail.

After-fracture redundancy analysis of an aged truss bridge in Japan

Abstract In the next 20 years, more than half of the bridges in Japan would be in service for more than 50 years. These include truss bridges those are generally considered to be non-redundant and fracture critical. With ageing, these bridges are facing an increasing risk of bridge collapse under extreme conditions. Therefore, it is essential to evaluate alternate load paths on existing bridge structures to avoid bridge collapse or replacement. In this paper, after-fracture redundancy of truss bridges is investigated through a case study for a five-span continuous truss bridge. Field tests were performed, and the displacements on key sections were measured in the test. According to the experimental observations and test results, a numerical model capable of simulating the present truss bridge was built and was used to investigate the after-fracture redundancy of the target bridge. Fracture of truss members in typical locations was considered in the numerical analyses, and the ‘R’ values of both intact and damaged trusses were compared. On the basis of the numerical results, a critical member in this bridge was also determined.

Renovation of existing steel railway bridges: Field test and numerical simulation

Renovation of the aged steel railway structures is of vital importance due to their long service life after completion. A strengthening method for aged steel railway bridges by using rubber-latex mortar, glass fiber–reinforced polymer plates, lightweight rapid hardening concrete, and reinforcing bars was introduced in this article. To confirm the real effect of the present strengthening method, field tests were performed on two aged steel railway bridges that have been in service for 87 and 61 years, respectively. Stress variations on the mid-span section of the railway bridge due to the running trains were measured in the field test, and the stress reduction effects as well as the load redistribution effects of the present strengthening method were also confirmed. Three-dimensional finite-element models were built, and the numerical results were in good agreement with the field test results. Besides, structural vibration and noise levels of both strengthened and un-strengthened railway bridges were measured, and the noise reduction effect of the present method was confirmed in the field tests. In addition, further nonlinear analyses were performed, and the applied load–displacement relationships as well as the load–normal longitudinal strain curves of the aged structural steel, the glass fiber–reinforced polymer plates and the rapid hardening concrete, were given. Both experimental and numerical results indicate that the present renovation method can greatly enhance the stiffness and reduce the stress levels of steel members, resulting in the extension of the residual service life of the aged steel railway bridges.

Design and periodic inspection of the kintai-kyo wooden arch bridge

Abstract The Kintai-kyo Bridge is a unique, five-span wooden bridge with three arches across the Nishiki River, the largest river of the Yamaguchi Prefecture, Japan. The central wooden rib arch is very rare in the world. The bridge has become a famous landmark because of its elegant structure and its aesthetic appearance that is in harmony with the surrounding picturesque landscape. It is a popular historical site and attracts many tourists. The wooden bridge has been rebuilt several times since its inauguration in 1673. The latest rebuilding was done in 2004 which was almost 50 years after the previous one. The original span length of the Kintai-kyo Bridge was close to the limit allowed for construction of wooden bridges during that time. In order to strengthen the bridge against floods, the best combination of wood and stone was used. Arch structure was adopted for the superstructure, and hollow stone piers of spindle-shaped crosssection were adopted in the substructure. This paper studies the origin of the arch structure of the Kintai-kyo Bridge because this arch is unique and different from the voussoir arch or the corbel arch, and its resulting elegant appearance. In addition, as a unique feature, periodical inspections of the Kintai-kyo Bridge have been conducted by the Waseda University every 5 years since 1953, where the weight of local high-school students is used as the load for testing.

Reliability and Redundancy of Two-Girder Steel-Concrete Composite Bridges under Uncertainty

As the bridge inventory ages and traffic volumes increase, the bridge owners are spending more on maintaining their current structures. AASHTO considers virtually all two-girder bridge systems as non-redundant, and each girder is considered as the fracture-critical member (FCM). Redundancy analysis of the twogirder bridges considering the uncertainty (damage scenarios) is investigated through a case study on a three-span continuous twin I-girder bridge. The FE analysis is employed to evaluate the load-carrying capacity after fracture of one main girder of the twin girder bridge. The damage locations are chosen at the mid-span section of the middle span, the side span, and the section near the continuous pier support. Damage of shear connectors near the moment contra-flexure regions and missing of one bearing at the middle and end support locations are also considered as potential damage scenarios in this study. On the basis of the direct redundancy analysis results, the present continuous two-girder composite bridge can be classified as redundant.

Measurement of Corroded Gusset Plate Connection of Steel Truss Bridge and Evaluation for Its Corrosion State

Notable accidents that the diagonal members of the steel truss bridges have broken due to the corrosion damage have occurred recently. Therefore it is expected to establish the rational and efficient maintenance management technique depending on the bridge types and structure characteristics. In this study, for the corroded gusset plate connection of the steel truss bridge which was cut out from the steel truss bridge, we measured the corrosion shape in detail using the laser measurement equipment, and evaluated the actual state of the surface corrosion outside and inside of the gusset plate connection.