Ryuutarou IBI This study aims to clarify the deformation characteristics of the compound truss bridges, combined fiber reinforced plastics (FRP) with the current steel material (SS400) during earthquake. Dynamic analysis by finite element analysis program OpenSees was done and its result was compared with the one of FORTRAN program. As a result, the maximum response displacement by OpenSees was bigger than that by FORTRAN program. The tendency of damping was admitted when the bridge was supposed as compound truss in the result of this analysis as well as the one in FORTRAN program.
Key Words: Fiber Reinforced Plastics, Compound truss bridges, Finite element method, Seismic response analysis
Kotaro ODA The prediction of damage for reinforced concrete piers influenced by the many earthquakes within endurance term is very important Japan. In this study, the prediction of damage state transition of reinforced concrete pier was analyzed by the earthquake risk analysis, elasto-plastic seismic response analysis, damage index, damage probability matrix and Monte Carlo simulation. The reinforcement effect to cumulative damage was for large, and about twice force of earthquake, with one earthquake tremor whose recurrence term was almost the same as the endurance term should be considered when the cumulative damage of structures was supposed, even if it is estimated every calculation point.
Key Words: damage index, elasto-plasticity seismic response analysis, damage probability matrix, Monte Carlo simulation
So KASAHARA In Niigata prefecture, salt damage on structures becomes serious because of its wide coastal area, the effects of periodic wind and so on. This study aims to build a database which has fundamental functions for the effective maintenance and management of reinforced concrete structures. Every parameter for structural specimens was set, and search expression, input item and the related to them were decided. With making to risk judgment function in the database, the risk for salt damage was estimated by using sample data.
Key Words: reinforced concrete structure, maintenance management, salt damage, database, risk judgment
Keita WATANABE After Hyogoken Nambu Earthquake in 1995, dynamic analysis is regarded important in seismic design of structure. In this study, the behaviors of structure in static load and earthquake were clarified by the analysis of reinforced concrete column. Also a fiber model was built by the finite element method software OpenSees, and static and dynamic analyses were done. The result of these analyses was almost in accordance with that of the past experiments, however, the difference of response acceleration in dynamic analysis was also found.
Key Words: finite element method, fiber model, reinforced concrete column, static analysis, dynamic analysis
Takeru ARAKAWA This study aims to clarify the deformation characteristics of the hybrid material truss bridges, combined carbon fiber reinforced plastics (CFRP) and glass fiber reinforced plastics (GFRP) with the current steel material (SS400) during earthquake. The response displacements were analyzed by finite element method (FEM) analysis, and the consequences were examined. As a result, the largest response displacement of the hybrid material truss bridges combining FRP were equal to the member only made with SS400, but great damping was recognized in the hybrid bridges.
Key Words: fiber reinforced plastics (FRP)，hybrid material truss bridge，dynamic analysis，largest response displacement，damping
Shougo INADA Frequent earthquakes are occurred in Japan, so it is important to know the structural damage by several earthquakes. In this study, the prediction of damage state transition of reinforced concrete structure after its lifetime was attempted by elasto-plasticity seismic response analysis, Monte Carlo Simulation, seismic risk analysis, the concept of damage index and damage probability matrix. As a result, it was clarified that effect on cumulative damage was different for each bridge pier. However, the cumulative damage of its lifetime could be considered by using the earthquake that had recurrence period with approximately five to ten times comparing with the lifetime of structure.
Key Words: elasto-plasticity seismic response analysis, Monte Carlo simulation, the concept of damage index, damage probability matrix
Koichi KOMIYAMA The examination of concrete durability is difficult because researches on concrete structure are executed separately and the results are gathered respectively. In this study, establishment of salt damage management database was examined in order to make better use of the data for its comparison. The database with a basic function by setting up parameters determining the related items for concrete characteristics was built.
Key Words: reinforced concrete, maintenance management, salt damage, database
Takashi HASEGAWA The method of calculating damage of structure based on earthquake input unit energy in a unit time and the equivalent absorption energy of the structure was investigated. The accuracy of value for bridge was found high when energy spectrum of excellent period was from 0.2 to 0.4 and gradient of equivalent absorption energy was 89 and over.
Key Words: reinforced concrete pier, earthquake damage estimation index, earthquake input unit energy, equivalent absorption energy, excellent period, elasto-plastic response analysis
Takashi HIRAYAMA Load by snow acts on structure heavily in snowy area and it may relate to the increase of damage in earthquake. In this study , P・ effect which referred to the snow load P and horizontal displacement of structure in earthquake was investigated by earthquake response analysis for two story wooden houses, which was assumed as a mass model. The danger of house collapse was also examined by comparing the force induced by earthquake and resistive force of house. As a result, the possibility of collapse may increase because of the influence of P・ effect for longer dominant period of old house.
Key Words: P･ Effect，snow load，wooden house, earthquake response analysis
Tomohiro OMORI In this study, response acceleration and displacement were analyzed, and examined about a vibration characteristics within earthquake by finite element method for the hybrid material truss bridge, combined two kind of the glass fiber reinforced plastic GFRP with the current steel material SS400, with three types of earthquake wave data. As a result, earthquake wave to input and a placement pattern of material show some difference of responses, however, damping of both response acceleration and displacement show favorable value for hybrid material bridge in case any waves are inputted.
Key Words: glass fiber reinforced plastic(GFRP), hybrid truss bridge, seismic response analysis, response acceleration, response displacement
Masaki KOYAMA In this study, investigated elasto-plastic response analysis by using finite element method software SAP2000 as fundamental examination of simple way of predicting the damage of structure by earthquake without elasto-plastic response analysis. Square section is used as analysis model and the wave of Niigata-ken Chuetsu Earthquake is inputted.Time-history response analysis is performed and the top center of pier is observed as the calculation point. Response acceleration of K-NET Nagaoka Branch is calculated approximately 2.5 times bigger than that of K-NET Nagaoka.
Key Words: Elasto-plastic response analysis, Finite element method, Earthquake input unit energy, Response acceleration, Time-history response analysis
Midori SATO In this study, the characteristic of earthquake was analyzed by the wave of Niigata-ken Chuetsu earthquake in 2004, and after this. As indicators, equivalent seismic intensity, earthquake input unit energy, acceleration response spectrum, maximum acceleration, maximum velocity, maximum displacement were used. Assuming that the earthquake intensity expresses extent of damage, it was also investigated to relationship of between earthquake intensity and each indicator. For lower structures, large destructive force for lower civil structures was shown in three wave type. In Ojiya of Chuetsu earthquake the force showed the most for middle structure. As a destructive force indicator, Earthquake input unit energy showed the highest correlation with earthquake intensity among the five indicators.
Key Words: Earthquake input unit energy, Equivalent seismic intensity, Acceleration response spectrum, Maximum acceleration, Maximum velocity, Maximum displacement, Correlation coefficient
Yukitada SHIRATA Truck scale is the one which measures weight of cars. However the best arrangements of structural beams are not sufficiently grasped. This study aims at cost reduction and save space of truck scale structure, calculates load distribution factor with Leonhardt method of grillage girder theory, under the condition that its structure regards as grillage girder, considering allowable stress of beam and examined the best arrangement of structural beams. As a result, the best arrangements are found six main beams with two cross beams.
Key Words: Truck scale, Grillage girder theory, Leonhardt method，Load distribution factor，Bending stress
Akiyuki SAITO In recent years, fiber reinforced plastics (FRP) has drawn attention as a new construction material. However seismic response characteristics of bridge with FRP are not sufficiently grasped. In this study, seismic response characteristics of hybrid truss bridge combining FRP and steel material SS400 were investigated. Dynamic analysis was carried out for a single material bridge with SS400 and hybrid material bridge with GFRP, and response acceleration and displacement were analyzed in five earthquake waves. As a result, the result for hybrid truss bridge was acquired better result. However in one earthquake wave the result was inverted. Seismic response characteristics of bridge were dependent on material arrangement, structural parameter and the characteristics of earthquake waves.
Key Words: Fiber reinforced plastics (FRP), Hybrid truss, Finite element method Response acceleration, Response displacement
Shogo MAEDA Using high strength RC beam is quite useful; however, the kinetic characteristics have not been clarified enough. In this study, it is primarily intended to clarify shear strength of high strength RC beam and its shear characteristics, and the shear strength calculation formula in the high strength area was evaluated. The formulas by JSCE, Suzuki, Niwa, Okamoto, ACI, CEB, and Modified Compression Field Theory (MCFT) were targeted. As a result, some accuracy for shear strength was found in JSCE, Suzuki, CEB formula, and MCFT. Moreover, shear strength aid not increase in high strength RC beam contrary to an increase of compression strength. In addition, effective height of high strength RC beam has a considerable impact on its shear strength.
Key Words: High Strength Concrete Beam, Compression Strength, Shear Strength, Diagonal Tension Failure, Regression Formula
Tohru MATSUOKA In Niigata-ken Chuetsu earthquake, extensive damage from the storm was caused in the Chuetsu district including Nagaoka city. It is very important to examine the destructive index of the earthquake to presume the damage of the engineering structure due to a large earthquake. In this study, about the main shock and aftershocks of the Niigata-ken Chuetsu earthquake and a past earthquake wave, in two observation points are in central Nagaoka and around Yukyuzan. The characteristic of the earthquake wave was compared and examined by using various indices of the acceleration response spectrum and earthquake input unit energy and so on. Input at a certain earthquake input total energy and unit time input to the structure during the continual time of the earthquake wave. As a result, it is surmisable that it was the same degree of destructive power in the Hyogo-ken Nanbu earthquake compared with the low house and the low building receive the destructive power to the house in low layer and the building in a low layer of the earthquake was large from an analytical result of this research compared with central Nagaoka as for around Yukyuzan and the vicinity of Nagaoka National College of Technology.
Key Words: Destructive index, Acceleration response spectrum, Earthquake input total energy, Earthquake input unit energy, Equivalent seismic intensity
Yasuaki MARUYAMA Truck scale is the one which measures weight of cars. This is mainly classified into two kinds such as pit type and pitless type. Especially the adoption of the latter has increased recently due to the possibility of cost reduction for setting, however, there is severe limitation of beam height. The method of the optimization for pit type truck scale was examined in this study aiming cost reduction. Structure of truck scale is grillage girder, and the load is distributed to main and cross beams. The coefficient for distribution was decided by Leonhardt method, Homberg method and Guyon-Massonnet method, and all of them was used to acquire the result in this study. Six main beams and six cross beam model was adopted and the dimension was changed and the optimal arrangement of beam was examined. Analytical result was found to have a little difference by upper three methods and the number of cross beam has less influence on the coefficient.
Key Words: truck scale, grillage girder theory, Leonhardt method, Homberg method, Guyon-Massonnet method
Daisuke SAKAGAMI As for the hybrid material truss bridge, combined the fiber reinforced plastic (FRP) with the current steel material (SS400), its deformation and cost convert weight were calculated by static analysis with finite element method considering the material layout, span and truss height. Especially, the calculation, considering the material layout when steel material (SS400) used for chord member and fiber reinforced plastic (FRP) used for web member were adopted, was achieved. As a result, the member only made with SS400 had a little advantage for cost in comparison with hybrid one when the span was short, while FRP ones were advantageous in the longer span because there was small influence of its own weight. The cost of bridge with hybrid material made by combining steel material (SS400) for chord member and carbon fiber reinforced plastic(CFRP) for web member was found to be lower than that of the current material structures depending on truss height when the span exceeded 50m.
Key Words: Fiber reinforced plastic, Hybrid material truss bridge, Finite element method, Static analysis, Cost convert weight, Deformation
Sohta TAKATSU Seismic reliability for reinforced concrete structure influenced by many earthquakes within lifetime is very important because many earthquakes occur in Japan. In this study, RC structure with several earthquakes within lifetime was estimated by the damage probability matrix, made by seismic risk analysis, bending and shear damage indices, SDOF earthquake response analysis and Monte Carlo simulation. As a result, expectation value of RC structure damage after lifetime was influenced by the types of earthquake waves and calculation places, and structural design is needed considering accumulative damage.
Key Words: RC structure, seismic risk analysis, damage index, the earthquake response analysis, the damage probability matrix, Monte Carlo simulation
Kazuya TADA In recent years, bridge with fiber reinforced plastic (FRP) as a new construction material has been prosperously studied, but dynamic vibration characteristics of bridge with FRP is not sufficiently grasped. In this study, hybrid material bridge combining FRP and steel material SS400 with excellently economical and dynamical efficiency was proposed. In this time, dynamic analysis was carried out for a single material bridge with SS400 and hybrid material bridge with GFRP, and response acceleration and displacement were investigated. As a result, a single material bridge with SS400 and hybrid material bridge were different in terms of displacement. Damping of hybrid material bridge was large, and difference of responses was remarkably shown by the types of input seismic waves.
Key Words: Fiber reinforced plastic (FRP), Hybrid material bridge, Dynamic analysis, Response acceleration, Response displacement
Takumichi TOYAMA It is important to investigate destructive index of earthquake wave because the earthquake duration characteristics are dominant to against the damage of a structure within earthquake. In this study, the correlation between some destructive indices and unit input energy within a unit period were examined considering the earthquake duration paid its attention to the energy which destroys structure. As a result, the Spectrum Intensity (SI), as one of destructive indexes, shows high correlation with earthquake input unit energy and 1-cycle and 1/4-cycle taken as unit time was found to make sense in case earthquake input unit energy was considered.
Key Words: Destructive index, Earthquake input unit energy, Earthquake wave characteristics, Spectrum Intensity (SI), Correlation
Yoichi OTSUKA In this study, the damage index which evaluates quantitatively the damage degree of the RC structure was examined for the effectiveness of RC structure damage. As a result, high correlation was seen among four indices, that is, ductility, damage ratio, normalized cumulative deformation and normalized dissipated energy when a real earthquake wave was inputted an object structure. However, when the experimental result of the reversed cyclic loading was used, it was difficult to judge the possibility of the reproduction for damage degree of the structure in earthquake only from this analysis. The damage index by Park et al. was considered not to be necessarily suitable as damage index of a structure, only under the condition of reversed cyclic loading.
Key words: Reinforced concrete pier, Damage index, Damage degree, Seismic response analysis, Reversed cyclic loading analysis
Masayuki HASHIMOTO In recent years, fiber reinforced plastic (FRP) has been observed as a new construction material, but dynamic vibration characteristics construction structure is not sufficiently grasped yet. In this study, combining FRP and current construction material, hybrid material bridge with excellent economical and dynamical efficiency was proposed. In this time as the preceding stage, dynamic analysis was carried out as an earthquake response only for a single material by finite element analysis. As a result, response acceleration and displacement of truss bridge made by GFRP, CFRP, and SS400 was calculated.
Key Words：Finite element analysis, Dynamic analysis, Fiber reinforced plastic (FRP), Hybrid material bridge, Response acceleration, Response displacement
Otowa MATSUDA
In this study, accuracy of rough damage estimation method for RC pier was examined by total energy within earthquake duration, unit energy within a unit period in the earthquake, and equivalent accumulative energy of structure. As a result of analysis, accuracy of the method is widely influenced by shapes of earthquake energy spectra. Furthermore it is adequate to consider equivalent period based on estimation of ductility factor of RC member as the limitation of equivalent period in structure.
key words: Reinforced concrete pier, Seismic design, Earthquake input total energy, Earthquake input unit energy, Equivalent accumulative energy, Energy spectrum
Aki MATSUNAWA
In this study, deformation and cost convert weight were calculated by static analysis with finite element method as for the hybrid material structure combined the fiber reinforced plastic (FRP) with current steel material (SS400). Especially, it was examined how the deformation limit value affect deformation and cost of the whole structure. As a result, considering with deformation limit, using SS400 in higher rate is advantageous for cost because of small deformation. However, when the span was long, FRP is advantageous because of its small own weight. When the span was longer than 200m and deformation limit was L/100, the cost of a bridge with hybrid material made by combining steel material (SS400) and Glass fiber reinforced plastic (GFRP) was found to be lower than that of the current material structures.
Key Words：Fiber reinforced plastic, Hybrid material truss bridge, Finite element method, Static analysis, Cost convert weight, Deformation limit
Misato Ohkubo Yaichi Mimura Predicting the damage of public works structures by earthquake is very important in earthquake-proof engineering. In this study, the tendency for earthquake input energy of seismic waves was investigated to examine the damage of structure by earthquake. The correlation between the characteristics of various seismic waves and structures, and the simple way of predicting the damage of RC bridge pier by earthquake without elasto-plastic response analysis were examined. It was shown that the prediction method of damage degree for RC pier without elasto-plastic response analysis might be applicable despite of less accuracy comparing to the elasto-plastic response analysis.
【keywords】Reinforced concrete pier, Earthquake wave characteristics, Earthquake input energy, Elasto-plastic response, Static energy
Michio Kimura In this study, deformation, natural period and cost convert weight were calculated by static analysis with finite element method as for the hybrid material structure combined the fiber reinforced plastics (FRP) with current material. Hybrid material structure showed medium characteristics of each material. The construction cost of short bridge that was combined mainly with current materials was calculated to be low. The construction cost of long bridge that was combined mainly with FRP was calculated to be low. Particulary the cost of bridge with hybrid material made by combining steel material (SS400) and Glass fiber reinforced plastic (GFRP) was found to be lower than that of the current material structures.
【key words】Finite element method， Fiber reinforced plastic，Deformation，Natural period, Cost convert weight, Static analysis，Hybrid material structure
Masatoshi Watanabe Fiber reinforced plastics (FRP) has drawn attention as a new construction material recently, and the pedestrian bridge with glass fiber reinforced plastics was constructed as a site-test in Okinawa prefecture. The evaluation of design by dynamic analysis has been taken up after the Hyogo-ken Nanbu Earthquake. In this study, the development of dynamic analysis program in constructing hybrid material structure by combining FRP with the existing construction materials was aimed. Simulative output results could be presented at the current stage.
【Keywords】Fiber reinforced plastics (FRP), Finite element method, Hybrid material structure, Dynamic analysis program
Kazuhiro IKEDU Narie NISHIZAWA For estimating damage accurately in the seismic design of structure and evaluating damage quickly after earthquake disaster, the simple method of estimating damage for structure is very useful. In this study, damage evaluation method based on the concept of RC pier was proposed by total input energy within earthquake duration, unit input energy within a unit period in the earthquake, based on the concept of equivalent accumulative energy of structure. The method of estimating the damage degree of the RC pier was also studied using elastic analysis without elasto-plastic analysis. It was found that the prediction of behavior in elasto-plastic was possible by the elastic analysis.
【Keywords】Reinforced concrete pier, Seismic design, Earthquake input energy, Energy spectrum, Equivalent accumulative energy
Daisuke SAKAI Tooru FUJITA Glass fiber reinforced plastics (GFRP) has drawn attention as a new construction material among the construction industry recently. Their deformation and vibration characteristics were analyzed by FEM analysis in this study when bridges with hybrid materials were made combining GFRP with the construction materials which have been used so far. The middle characteristics of the combined materials were shown. Their costs were also analyzed because reducing construction cost of structures was demanded. The costs of bridge with hybrid materials made by combining steel material (SS400) and GFRP was found to be lower than the current structures.
【Keywords】Finite element method, Hybrid material structure, Cost convert weight, Deformation, Natural period