In the thin shell theory, strains are treated approximately such as Love's first-approximation and Flügge's second-approximation theories. In this study, Navier-type exact solutions base on first-order shear deformation theory of deep-thick doubly curved shells are determined. The modified strain-displacement relations that all strains vanish for any rigid-body motion are used and the stress resultants are treated exactly. By using numerical examples of simply supported deep-thick doubly curved shells, the application of a Reddy's shallow shell theory and the effect of modified strain-displacement relations are investigated.

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Falling rock tests on a slope covered with new type drapery with the special net and installed the buffer devices have been carried out.
This drapery consists of the anchorages, the normal cables and the special devices installed between the anchorages and the wire cables. This drapery suitable for the steep and extensive slopes and advantageous to the construction cost. Firstly this paper describes the testing results for each member, and secondly the testing procedure of the prototype experiments. Finally test results are compared with the numerical calculation results by LS-DYNA.
It becomes clear that the behavior of this type drapery can be estimated by the numerical calculation.

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It is necessary to take the length of girders into consideration in making clear the collision mechanism of girders, since this phenomenon is really a wave propagation problem. Hereupon, the investigation was made for the influence of the girder length on the shock absorbing effect of rubbers through collision experiments using 4-different lengths of testing girders. It was found the collision stresses generated are proportioned to the girder length, and the generated stresses can be estimated by the impedance method based on the average modulus of deformation of shock absorbing rubbers obtained from the experiments. Furthermore, with the aid of numerical analysis, it was shown that the collision stresses produced in an actual length of girders can be estimated by assuming the modulus of deformation of shock absorbing rubber during the period of collision.

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In cold region, a heat insulator for icicle prevention has been developed in the new constructed and existing tunnels. In order to determine the necessary length of anti-icicle treatment from tunnel entrance area, this paper presents a theoretical equation for estimating the temperature in the tunnel. The equation is obtained using theoretical model considered heat convection/conduction between the tunnel ground and the air flow in the tunnel. Applicability and accuracy of the equation are examined by comparing the calculated results with measured results. It is found that the calculated values well agree with those measured in the field.

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This paper aims at discussing the effect of the crushed stone dimensions on the passive resistance. We conducted the experimental study on the passive resistance of the crushed stone, changing the dimensions of the crushed stones. Deformation characteristic of crushed stone was monitored by the deformation markers. In addition, sonic monitoring system was applied in order to identify the particle crush coordinates. We also conducted the distinct element analyses in order to reproduce the deformation characteristic of crushed stone.

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Rectangular columns without stiffened rib plate were fabricated by using laser beam welding and conventional arc welding. In the case of the specimen assembled by laser beam welding, geometrical imperfection and compressive residual stress were smaller than those of the specimen assembled by arc welding. Ultimate strength of the specimen assembled by laser beam welding was larger than that assembled by arc welding. Residual compressive force (F*) was proposed as the parameter expressing the effect of the residual stress for the ultimate strength. Using the parameter, reduction of ultimate strength due to welding residual stress could be illustrated.

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In the current design procedure for recent continuous composite steel-concrete bridges at an internal support under negative bending moment, the lateral torsional buckling theory is applied to evaluate an allowable stress in disregard of lateral restraint of top flange by a concrete slab. In actual continuous composite bridges, instead of the lateral torsional buckling, restrained distortional buckling may occur. This paper proposes a design procedure for the restrained distortional buckling of continuous composite girders under negative bending moment.

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Railway steel bridge accidents obstructing train services often occur due to the collision by the construction vehicle exceeding the limited height passing under the over-road bridge. In this study, we investigated residual load carrying capacities of steel girders subjected to collision deformations. Firstly, we conducted static vertical loading test on I-section riveted girders of an aged steel railway bridge after they were subjected to local deformations at the lower flanges. Next, we investigated analytically the load carrying capacities of I-section riveted girders with local deformation by using a multipurpose FEM code LS-DYNA. Based on these experimental and analytical studies, we can conclude that an influence of local deformations on the load carrying capacities of I-section steel girders is relatively small unless the deformations are excessive.

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Recently, a number of two I-girder bridges are gradually constructed in Japan. During construction especially incremental launching, it is important to ensure the safety for buckling due to patch loading because two I-girder bridges have the structural characteristics compared with traditional plate girder bridges. In Japan, there are two different specifications generally applied in bridge design, which lead to the different result each other. In this study, the actual difference in the design due to the specifications is evaluated. The parameter study is demonstrated varying the loading width of applied patch loading and the property of the web. The structural analysis is based on finite element method considering the local geometry. Moreover, for the case the examination is not satisfied, appropriate structural details are hereby proposed.

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This paper presents the three-dimensional free vibration analysis of solid circular cylinders with any lengths and arbitrary boundary conditions using the B-spline Ritz method based on the theory of elasticity. The proposed method is formulated by the Ritz procedure with the double series of B-spline functions as amplitude displacements and the Fourier series. To demonstrate the convergence and accuracy of the present method, several examples are solved, and the results are compared with other published solutions by the Ritz method with global functions based on the theory of elasticity. Rapid, stable convergence and excellent upper bound solution are obtained by the present method. Moreover, the effects of length-radius ratio and circumferential wave number on frequency parameters of solid circular cylinders having clamped and stress free boundary conditions are also investigated.

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It is quite important to mine ores with forming a stable retaining wall from the viewpoints of the safety for miners and the scenic preservation of the mine. However, there have been always a lot of the collapse of retaining wall. There is few research to consider the mechanism of the collapse of retaining wall during rainfall though the investigations or observations of the collapse of retaining wall are well studied. Thus, in this study, the finite element analysis for the collapse of retaining wall is carried on and its stability is considered from hydraulic and mechanical points of view. The results reveal that the intensity and elapsed-time of rainfall as well as the properties of rock mass such as a permeability coefficient are quite important.

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The paper attempts to enhance the VOF-basedfinite element method for snow deformation problem by taking into account the deposition process. The variation of snow shape due to the deposition is modeled by involving the supply from snowfall in the advection equation of the VOF function. The snowfall process is described by simplified advection and diffusion models. The developed method is verified through a comparison with a semianalytical solution for a one-dimensional deposition problem. Besides, the simulation of Nakamura's experiment for snowpack with an embedded beam is achieved. Based on these analyses the significance of snow deposition process and deformation hardening in the mechanical behavior is discussed.

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This paper presents a semi-full-scale experimental study of the steel frame erosion control dam in which the gravel filled, and the gravel filling effect on the shear resistance of the dam structure. The steel frame structure, which has 3m-height and filled gravel in its inside space, is horizontally loaded until a shape steel element broken, and its resistance is compared with that of the structure without the filled gravel. The empirical estimation method previously proposed by one of authors is verified by these experiments. And the filled gravel resistance effect on the design of the structure is discussed by using some typical design cases.

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There are many proposed methodologies for implementation of asset management of bridge group. Some of them try minimizing the LCC of each bridge in the group under consideration, but the difference between annual budgets becomes impracticable. Thus in this report, an approach is proposed to equalize the annual budget for the bridge group repair by using the genetic algorithm with two dimensional string structure. Numerical examples show that the proposed approach works effectively.

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In recent years, bridge engineering concern has shifted from the construction of new highway bridges to the maintenance of existing ones. In this study, an attempt is made to develop an optimal maintenance plan for reinforced concrete (RC) decks of highway bridges. Emphasis is placed on how to obtain an appropriate order of repair for the existing decks by considering the characteristics of the road network and the concept of life cycle cost. This optimal maintenance planning is formulated as a cost benefit problem for consumer surplus. Genetic algorithm (GA) is employed here to find a practical and rational solution for the maintenance problem.

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In the maintenance of infrastructures in the performance design system, the counter measures in a emergency when structures are collapsed are required in addition ordinary maintenance service. The authors proposed a new maintenance approach named the live management approach to manage the maintenance of structures at the ultimate limit sate as well as at the service limit state. In this paper, using this live management approach, it is constructed a live management system for highway networks in a seismic disaster emergency at the central area of Tottori City. In construction of the system, removable routes on the highway-network to the destination for various supposed seismic disaster patterns are analyzed based on the reliability evaluation of highway network and their results are stored in the live design database system. Actual damages are immediately surveyed after the occurrence of earthquake, and the simulation results stored in the system .are updated and the effective decision-making is immediately performed using this proposed live management system.

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The form of the bridge strongly depends on the structural frame. This is a characteristic of bridges. Therefore, when the bridges are designed, it is necessary to consider about the structure and the form simultaneously. Mechanical relativity is an important concept to understand the relationship between the structure and the form of bridges. In this paper, we propose a new theory of mechanical relativity of bridges. The theory expresses the symmetrical property of the structure and the form quantitatively. Moreover, we show the mechanical relativity of not only "bridge type" but also "horizontal structural system", "structural system for the load distribution to girders", and "structural system for the load transmission from floor to main structure". We propose a way of expression of image of the mechanical relativity of bridges, which are three-dimensional structures.

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The authors performed a research using test trucks for a three-lane prestressed concrete bridge with 37.47m span that vibrated greatly. As the results of the research, the bridge had the frequency of the 1^st bending vibration (about 3.0Hz). And also, since the frequency and that of general vehicle's vibration (about 3.0Hz) is close, the bridge and vehicles had caused coupled vibration. Moreover it was clear that the bridge had vibrated greatly, only when the test truck had ran at the 2^nd slow lane. Because vehicle's suspension spring vibration had been generated by the road roughness with long space period nearby the expansion joint of the 2^nd slow lane. This paper describes the vibration characteristics of the prestressed concrete bridge coupled with the vehicle's vibration generated by the road roughness with long space period nearby the expansion joint. Besides, this study also examined the countermeasure to decrease the vibration by the dynamic response analysis due to running vehicle.

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Elaborate three-dimensional finite element models are generated to deal with the bridge-vehicle interaction dynamics of simply supported twin I-girder bridges. The bridge is modeled in detail with solid and shell elements. The studied vehicle is idealized as 3D non-linear model consisting of several lumped masses connected by rigid beams and supported by spring-dampers. Gap and actuator elements are incorporated into the tire models to simulate the separation between the tires and road surface, and road surface roughness, respectively. Correlated road surface roughness profiles are generated from power spectral density (PSD) and cross spectral functions. The models are capable to consider both bridge and vehicle responses with virtually no limitation on the complexity of vehicle and bridge. The dynamic responses of the twin I-girder bridge are extensively investigated under conditions of various roughness classes, vehicle speeds, etc. From numerous calculated results, some useful information regarding to the impact factor of the studied bridge is presented.

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In this research, vibration characteristics are estimated from the ambient vibration of highway bridge by the block companion form realization theory. Two methods are stated herein such as formulation of block companion system matrix; (i) directly from block Hankel matrix, (ii) from ARMA model parameter G through Yule-Walker equation. These methods have applied to a 152m long Langer bridge and its dynamic characteristics were estimated automatically from multipoint measurement of ambient vibration. As the ambient vibration characteristics affect the estimation accuracy, two different cases were taken into consideration and the estimation accuracy was evaluated.

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This article examined how the vibration characteristics of the steel truss bridge changed by the real damage of diagonal member. At first, for the truss bridge where diagonal members corroded and cracked, ambient vibration measurement and vibration measurement by the load car run testing were performed. Secondly, the accurate identification of the vibration characteristics change by RD-ERA method was tried with the vibration data provided. As a result, some knowledge was provided about a change of global and local mode characteristics by the partial damage of diagonal member.

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In this research, we examine the reproducibility of the actual dynamic behavior of the simple viaduct model with the pseudo-ground by the dynamic response analysis. First, we conduct the vibration test of the pier and superstructure member, and the movable bearing. Second, we identify the damping property from the experimental results. Third, we construct the numerical model according to the test model so as to reproduce the natural frequency and the damping property of the viaduct model. Finally, we try to reproduce the vibrational behavior with the pseudo-ground by the dynamic response analysis of the numerical model which is constructed on the basis of the finite element method with the rotational spring and dashpot at the pier base. As a result, the dynamic behavior of the viaduct model is successfully reproduced by the numerical model under the earthquake excitation rather than another numerical model considering Rayleigh damping matrix.

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Locomotion of animals, such as walking and running, is generated and controlled by the central nervous system called as the central pattern generator (CPG). Recently, the CPG framework has been utillized to develop locomotion controllers for autonomous walking robots. Therefore, in this paper, a neural-oscillator-model proposed by Matsuoka is investigated to grasp some useful information for human-induced lateral vibration on congested pedestrian bridges. Numerical simulations were carried out taking into account various combinations of the parameters of the neural-oscillator model. It was ascertained that the neural-oscillator might be one of the useful model to explain the synchronization of a fairly high part of all pedestrians being on the bridge.

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Rubber with viscoelasticity is not only well known elastomer as shock absorber, but also one of the most powerful materials for cost performance in civil engineering use. In this research, we evaluated mechanical property such as an energy absorption and initial elastic modulus of four kinds of rubbers by the mechanical measurement. On the other hand, the dynamic heat capacity of those rubbers is measured in the glass transition region for various frequencies by TMDSC. From the complex heat capacity, we calculated the volume of Cooperatively Rearranging Region (CRR) V_α. Moreover, we discussed energy absorption and carbon black reinforcement of rubber from comparison of mechanical property and V_α.

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Inversion technique is often used to evaluate stress drop of source mechanism, Q value of path characteristics and so on. It is well known that Fourier amplitude spectra have clear information such as source intensity, path attenuation and site amplification, in contrast with Fourier phase spectra (phase spectra). In this paper, inversion technique is applied to phase spectra of the small earthquake motions to decompose them into source and path characteristics. As a result, it is found that phase spectra are obtained as a frequency-dependent and non-linear function with respect to frequency.

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It is important to estimate the site amplification effects especially due to the deep subsurface structure in evaluating the seismic design ground motion. The site amplification factor for deep basin structure by the spectral inversion analyses shows characteristic that cannot be necessarily explained by the one-dimensional amplification effects: no peak frequency and high amplification factor for the frequency less than 1.0 Hz. We aim at discussing the site amplification characteristic for deep basin structure by the two-dimensional finite element analyses. We paid close attention to the effect of incident angle on the site amplification factor.

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The purpose of this paper is to set the ground site amplification factors using the strong motion record of Hokkaido. The results come from the tendency which is similar for 6 selected earthquakes. For the estimation of ground site amplification factors, geomorphology classification by the Digital National Land Information was used. It was concluded that there were areas which do not show the tendency of site amplification factors as estimated by the strong motion records of Hokkaido. Investigating the cause, it found that there were regional characteristics and the influence was stronger than the geomorphology classification. Therefore, when attempting to focus on a specific area, the tendency calculated by the site amplification factors of the strong motion records, was further improved.

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In this study, the surface wave exploration and microtremor measurement were carried out at the embankment of irrigation pond. Resultant conclusion are as follows. (1) It became clear that the extraction of high velocity zone which is caused by impervious grout in the embankment was possible and that it was easy to distinguish the boundary between embankment and foundation. (2) The S-wave velocity of the embankment roughly indicated the value of 200-300m/s and N-value of 10-30. (3) Fourier spectral ratios of the horizontal component to the vertical component(called H/V ratio) were calculated and the predominant periods were recognized through them. It was approximately 0.3 second. (4) The S-wave velocity and the predominant period calculated by N-value roughly agreed with them got by the surface wave exploration and the microtremor measurement.

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Relative displacement between piers is one of the main causes of earthquake damage of spillway which is composed of concrete piers with different shapes and different dynamic properties. In order to evaluate seismic safety of spillway, it is necessary to estimate the relative displacement accurately. In this study, I have made 3-D dynamic analyses regarding earthquake behavior of existing spillway against strong earthquake motions, and made clear the mechanism of earthquake damage of concrete spillway. As a result, it is considered that the dynamic behaviors of piers are largely affected by the shapes, the dynamic response properties, and the frequency characteristics of motions. The seismic measure by connecting the piers with the reinforcement materials is effective to reduce the relative displacements.

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With the rapid development of earthquake engineering, Earthquake Early Warning has come to be put to practical use. In this study, we have developed an immediate evaluation method for earthquake damage of existing structures by combining 3-D nonlinear dynamic analysis and Earthquake Early Warning. The procedure for immediate evaluation developed in this study is constituted by two stages, namely one is an advance evaluation at peace time and the other is an immediate evaluation at earthquake time. We made the case study in regard to the exising dams, and examined the applicability of the method proposed. The proposed method is useful to mitigate the human, physical damage by earthquakes, can be broadly applied to various kinds of structures.

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An earthquake response analysis has been carried out for a deck-typed steel truss bridge, the gravity center of the deck being far above the gravity center of the truss girder, by using the standard Level 2 ground motion. This analysis is a dynamic analysis that considers progressive collapse with both material and geometrical nonlinearities being taken into consideration. In this paper, an analysis method of progressive collapse is proposed and the nonlinear seismic behaviors and members' damage sequence of the steel truss bridge are investigated by this analysis until collapsed state.

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Bridge supporting communication cable conduits is one of the important facilit ies in the NTT outside tele communication network , which is built across the river, holding many cable conduits. Seismic evaluation of the conduits bridge especially for a Level 2 earthquak e motion should be conducted as a matter of priority , because the damaged bridge due to a seismic attack may cause worse influence on telecommunication traffic at the disastrous time. The simplified seismic evaluation method for several types of the condui ts bridges is proposed in this paper. According to the definition of seismic performance, safety both the bridge and the conduits on it can be evaluated simply, taking account of subsoil liquefaction near abutment.

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This paper investigates the possibility of pounding, deck unseating and tangential joint residual damage depending on the curvature radius. Furthermore, an evaluation of the effectiveness of the use of cable restrainers on the overall 3D seismic response of highway viaducts is presented. For this purpose, the bridge seismic performance has been evaluated on four different radii of curvature, considering two cases: restrained and unrestrained curved viaducts. Depending on the radius of curvature, three-dimensional non-linear dynamic analysis shows the vulnerability of curved viaducts to pounding and deck unseating damage. In this study, the efficiency of using cable restrainers on curved viaducts is demonstrated, not only by reducing in all cases the possible damage, but also by providing a similar behavior in the viaducts despite of curvature radius.

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This paper presents a basic study on seismic retrofit of an existing steel cable-stayed bridge. A flexible structure such as steel cable-stayed bridge behaves three dimensionally during a big earthquake, therefore biaxial bending phenomenon occurs in main girder and pier. Therefore firstly nonlinear analysis using fiber models is conducted, and results are compared to those obtained by usual frame structure analysis. After installing the damper and other devices for seismic retrofit, some part of main girder remain in plastic region during large earthquake. Therefore secondly residual displacement of girder in plastic region is obtained by static finite element analysis, and using the numerical results seismic safety of the bridge is discussed.

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This paper demonstrates the accuracy of measurement of response displacement of reinforced concrete bridge column models that were tested under multi-directional earthquake loading on a shake table. The effects of slip/rocking of a footing and vibration of a setup frame that displacement sensors were fixed to on the measurement of response lateral displacement were investigated. The deformation of the setup frame was estimated by integrations of response acceleration by Fast Fourier Transform (FFT) and response displacement spectra. It was found that the measurement of the response displacement may include 1%-30% error due to the deformation of the frame. Accuracy of the measurement of response displacement by integration of response acceleration and by a motion capture system is also discussed.

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RC piers of continuous PC-girder bridge was damaged due to Niigata-ken Chuetsu earthquake in 2004. Field investigation of the damages was performed, and numerical damage simulation was carried out with nonlinear seismic response analysis in longitudinal and transverse direction. It was found that, in transverse direction, the continuous girder constrain piers to bend and reduced the damage at the termination area of main reinforcement. In order to verify this effect of decreasing of damage, parametric studies were performed on the structural type of the girder and input seismic motion.

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Adhering carbon fiber sheets onto RC piers is one of the seismic strengthening methods. When the pier has an irregular shape, however, carbon fiber sheets cannot be adhered continuously around the pier and the edge of the carbon fiber sheets have to be fixed with steel plates and anchor bolts. This fixing method has many shortcomings. For example: (1) The steel plate is heavy, (2) The execution of work is dangerous because a crane must be used to lift the steel plates, and (3) The construction period is long because after fixing the steel plates and anchor bolts, resin should be injected between the carbon fiber sheets and the steel plates. Then, an alternative fixing method using CF-anchors, which consists of bundles of carbon fiber strands, was developed, the equation of adhesive strength between CF-anchor and carbon fiber sheet was proposed and compared the calculation adhesive strengths with the experimental data. The result said that the experimental strengths were good agreement with adhesive strengths calculated using the proposal equation.

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The purposes of this study are examining the seismic response of the bridge foundation with battered piles at the deep, soft ground condition, as well as investigating the effectiveness of the sheet-piles installed method newly developed. Because of its geometrical configuration, the foundation with battered piles has the dynamic characteristics that the footing rotates to the opposite direction against the inertia action on the superstructure due to the ground deformation during the earthquake. This may cause severe damage at the pile cap. The sheet-piles installed method proposed in this paper can reduce the damage of the pile cap by restraining the rotation of the footing utilizing the sheet-piles installed around the foundation. A series of shaking table tests and the FEM analyses were performed for the investigation, which includes the sheet-piles installed and normal conditions. Following results were obtained. 1) Seismic characteristics of the foundation with battered piles were confirmed. 2) The effectiveness of the sheet-piles installed method was verified. 3) FEM analysis for this structure is feasible with introducing the appropriate ground spring model.

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To preserve the function of bridges after level 2 earthquakes, shear panel dampers (SPDs) with the high seismic performance have been developed and their applicability to bridges has been investigated analytically and experimentally.
In this paper, for the purpose of the application of the large-scale bridges and the improvement of the energy dissipation performance, the low cycle fatigue characteristics of the stiffened SPDs were investigated through the cyclic loading tests. As results, it was confirmed that the stiffened SPDs have high durability for low cycle fatigue by installing the stiffeners adequately.

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In this paper, to improve seismic performance of upper-deck type steel arch bridges against transvers directional earthquake motions, a method using two kinds of shear panel dampers installed at gusset plates of struts or arch ribs was proposed. Then dynamic analyses of a representative steel arch bridge with shear panel dampers were carried out and dynamic performance was compared with one of the original structure without dampers.
As a result, it was confirmed that this method was one of effective ways to upgrade seismic performance but the influence of the additional moment of struts and the stress concentration of joints should be estimated adequately.

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Recent demand of cost reduction for infrastructure in this country searches more economical devices in every aspect. In the seismic field, shear plate damper using low yield steel is considered as one of installations to meet such needs. In order to investigate higher seismic performance for the shear damper, strain distribution properties of the shear panels are investigated based on image processing technique under cyclic loading test. The high precision of the measurement by the image processing system was confirmed by comparing with the measured value by strain gauges. Various shapes of shear panel are served in the test and their strain distributions are obtained as well as load - displacement relationship.

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It is known that great possibilities to develop ocean spaces which may be used as resident areas, airports, power stations, etc. can be provided by offshore structures with a large deck area. The dynamic response properties on an offshore structure of truss spar type are significantly depended on the wave force evaluation. In the present study, under the assumption of potential flow and linear wave theory, the diffraction in each fluid region can be expressed by an eigenfunction expansion method. By using the wave force interaction obtained by the method, the dynamic response of truss spar structure is examined and compared with the case of using Morison equation. It is suggest that the effect on interaction based on diffraction theory has important roles on the reliable evaluation of the dynamic response for the truss spar structure.

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The flow around two cylinders shows more complex phenomena than that for a single cylinder. Depending on the arrangement of the cylinders, the responses due to the flow behavior present various aspects. In this study, numerical simulations are performed to investigate the flow around two circular cylinders of equal diameter in staggered arrangements at a subcritical Reynolds number. The center-to-center distance ratio of the cylinders is set to 2 and the angle of incidence is varied as 5, 10 and 15 degrees. The incidence-angle dependencies on the flow pattern, the aerodynamic forces and the Strouhal number are investigated. In particular, a bistable flow pattern is obtained as reported in several experimental studies and its characteristics on the flow field and the forces are discussed.

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In this paper, time-domain modeling of bridge deck flutter is first developed. The frequency dependent self-excited forces acting on a bridge deck are approximated in the Laplace transform domain by rational functions. The least-square matrix formulation of the rational function approximation is applied to flutter derivatives of the Akashi Kaikyo Bridge and airfoil. Besides, numerical analyses of the wind-induced response of the Akashi Kaikyo Bridge were conducted to facilitate the discussion. After that, the vertical deflection and torsion at the span center of the Akashi Kaikyo Bridge caused by buffeting and self-excited forces using the results of approximated flutter derivatives are examined to investigate the sensitivity of the approximation to the wind-induced response.

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The aerodynamic stability of a Suramadu cable stayed bridge was investigated by a wind tunnel test. All tests in this study were carried out in smooth flow. Some fairings were examined to improve aerodynamic stability. The response characteristics of this model with the fairing were investigated by a spring supported sectional model. The visualization test was carried out to investigate the effect of the flow around the model on its aerodynamic stability. As the results of this study, it was indicated that the fairing hardly affects the flow below the model and the aerodynamic stability is controlled by the separation strength (vorticity) and the thickness of separation bubble above the model.

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The viaduct over Shinonome Channel, which is in the Harumi line of Metropolitan Expressway, is a three span continuous bridge with 132m of center span and is located 9m above of the existing bridge. At the provisional opening stage of the viaduct, only side ramp bridges are going to be constructed in advance of the main line. Each ramp bridge has one box girder section, whose height is approximately as same as the width. Spring supported wind tunnel tests were conducted mainly in turbulent flow. The turbulent flow was simulated so as to match well over the range of bending frequency of target turbulent power spectrum. It is found that the existing bridge makes the galloping performance worse and that the turbulent flow gives better galloping performance. In conclusion, galloping occurred over the design wind speed and vortex-induced oscillations were not observed in the turbulent flow.

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Some deflections measured under both tests of real wheel loading and the so-called IIS method in the field for several deck slabs improved by four type's strengthening engineering methods applied in actual bridges are respectively compared with numerical values calculated individually by analytical solution derived from thick plate theory in applications to slab consisted of multi layer system. On the other hand, because actual deck slabs generally have continuous properties in the wide direction, clamped conditions approximately obtained from a technique by setting dummy girders near simply supported edges are substituted for actually combined conditions between main girders and slab through numerical procedure. In this paper, it is shown that several calculated values almost coincide with results of measurement for slabs widely spread from primary stage damaged by cracks, stage stiffened by steel plate to stage strengthened in twice by SFRC in the field, further explanations of deflections increased due to stripping of steel plate easily are easily able to verify in comparison of fruits reduced from this analytical solution.

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In this paper, an attempt is made to develop a structural health monitoring system that can adapt to the structural systems and environments with noise, by introducing the learning ability. At the previous research, a health monitoring system that can adapt to the structural systems and environments through the learning ability was developed with the recognition rate of over 80%. By introducing the learning ability, it is unnecessary to prepare any previous knowledge and examination for the underlying structures and environment. However, the previous research could not account for the effects of noise involved in data obtained from the sensors. In this paper, through the numerical examples, it is concluded that the proposed system can recognize the change of structural characteristics and condition states even under the noisy environment.

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Generally, various structural performances are required for the bridge. However, it is very difficult to evaluate all of performances quantitatively. Accordingly, in this paper attentions on performance and damage of existing bridges were paid. From the point of view of the performance, design data on main girder, deck plate, pier and Bridge-fall prevention system, of many existing bridges were collected and a restoration design was made. A simplified method to quantify the each performance level of bridges by data analysis (with parameters of construction age, applied specifications, and structural types) was proposed. While, from the point of view of the damage, we paid attention on importance and damage level of the structure member of bridges. We offered a simplified method to determining priority in countermeasure by the result of bridge inspection. Furthermore, We offered a new method to determining ultimate priority in countermeasure based on judgment of overall priority in damage and remaining performance.

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The contribution of the highway network to physical distribution service is very large. In this paper, the repair ranking determination of a bridge is determined using the asset value of a bridge, the parameter of user cost, and the parameter quantitatively evaluated in physical distribution service. In case where it performs comprehensive evaluation in consideration of two or more parameters, it is important to decide the weight of this parameter nothing arbitrariness. Then bridge maintenance rank by using the parameters considering the weighted asset and social value and Data Envelopment Analysis (DEA) is dealt with in this paper. Moreover, the validity of these methods is verified by using the actual bridge data. As a result, if bridge health index is keeping high level but social value is high quality, preventive maintenance is suggested.

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