Mio IGARASHI The purpose of this study is development and trial of new inspection system for public structures by citizen participatory with smart phone. In addition to constructed functions in previous year, the system were performed about the contribution method was improved in this year. New functions were added, for example, working with android smart phone, tutorial system, and so on. This system is made to expect more active contribution. It was tested for a month in the school and around Nagaoka station, and the effectiveness of improved points were examined. As a result, damage information of 32 locations was collect. All damages were confirmed by real investigation. Though there were various effects in improved the system, the possibility of the system was confirmed.
Key Words: smart phone, public facilities, citizen participation, community site e
Akira SHINAGAWA The purpose of this study is to examine the surface quality test of existing concrete structures in national route 404 Nagaoka Tozai road. These tests are measured with surface water absorption test (SWAT) equipment and visual rating method, and is used in comparative investigation. As a result, differences of surface absorbing water speed was considered to cause by rainfall, construction season, air temperature, tightness of lock bolt of SWAT and measuring points. Visual rating method is considered to appear to take effect on large difference of surface quality.
Key Words: surface quality, concrete, SWAT equipment, visual rating method
Taishi TSUCHIDA In this study, bridge inspection system and inspection data browsing system are developed by using tablet computer as a method of efficient management of bridge. Bridge inspection system in Japan is based on bridge regular inspection manual 2014. Bridge inspection data browsing system in Kyrgyz Republic is built subject to about 1100 bridges and 5 tunnels. Functions of extraction are developed in the system, the bridge need preferentially management and screen of simple inspection.
Key Words: tablet computer, bridge inspection system, bridge regular inspection manual, bridge inspection data browsing system
Jun MARUYAMA In this study, the tendency was analyzed from the results of bridge inspection data targeted at 9893 bridges managed by municipalities in Niigata prefecture. About 80 percent of all target bridges were small less than 15 meters, rate of concrete bridges was high in bridge type, more than half of target bridges were unknown the construction year. In worst value of main member, there were many relatively good bridges, on the other hand, there were about 30 percent bridges needs repair. In addition, there is a possibility that bridge brief inspection system is available to more than 80 percent of all target bridges.
Key Words: bridge inspection, elements of bridge, bridge type, construction year, worst value of main member, bridge brief inspection system
Yoshiyasu WATANABE In this study, tunnels constructed in past were investigated cause of damages which were found many damages in few years from starting service. As a result, damages of comparatively serious were separation of concrete. And most of them were located on ceiling of a tunnel. The results showed that damages of tunnel were not only being caused by degradation over time, but also being caused initial failure. So initial failure in construction may be cause of serious damage.
Key Words: mountain tunnel, NATM, inspection record, span, initial failure
Asami OGAWA The purpose of this study is development and trial of new inspection system for public structures by citizen participatory with smart phone. The community site with registration system was made to get information by pictures and comments mainly. The authenticity of the information was confirmed because it was an essential to input location information. It was tested for a month in the school under the support of students and the effectiveness of the site was examined. As a result, 20 people registered on the site and damage information of 24 locations was collected. All of the damage could be confirmed on the investigation and it was found that it might have effectiveness as a method of collecting information.
Key Words: smart phone, public facilities, inspection, citizen participation, community site
Fumika ONOGUCHI In this study, the column of old movable gate dam of Ohkohzu diversion canal, that is used for 80 years over, was examined about damage situation, to grasp deterioration condition of each column . Damage figures of the dam pillar made with the photograph of dam pillar at the time of scrapping and tendency of deterioration was grasped and investigated through the comparison of each columns. As a result, the damage by poor construction work and the damage influenced by internal steel frames were confirmed. By comparing with the document of 2002, the development of some damages was also found.
Key Words: movable gate dam, column, concrete, damage figures, cause of damage
Yusuke SASAKI The purpose of this study is to solve the problem of indirect visual tools which was proved by brief inspection system in previous year, and to examine the validity of improved brief inspection system through the inspection in another municipality. This tool enabled the 17 bridges out of 19 one which could not be done by visual inspection in previous year, to achieve indirect visual inspection. In the inspection in other municipality, method of indirect visual inspection was effective to all bridges because indirect visual inspection could be done for all the bridges. The result showed that 3 bridges needed detail inspection and 39 bridges did not.
Key Words: Tablet computers, bridge brief inspection system, indirect visual, field test, detail inspection
Shu YAMAZAKI The purpose of this study is to analyze tendency of deteriorations of bridges managed by Hokuriku region of road administrator. Factors of deteriorations and damages of progress status were analyzed on the results of 252 bridges inspected two times in Niigata, from 2004 to 2011. The results showed that material degradation was the main factor of damage for steel bridge, poor water proof and drainage works for concrete bridge. Each progress status was different and spalling in concrete bridge indicated the high rate as the first damage.
Key Words: bridge inspection, bridges, factor of deteriorations, progress of deterioration
Masato SAWAKI The validity of brief inspection system was analyzed through the inspection of 163 bridges in a municipality in this study and the effectiveness was examined. As a result, a bridge span of 89% could be inspected within 7 minutes by this method. Also monopod and digital camera were used as method of indirect visual inspection of floor span underside. Method of indirect visual inspection is effective for span of all of 72%. and other spans were evaluated as "no visual inspection". The spans with big damage influenced on structure were extracted from this method. The result was shown that 16 bridges needed detail inspection, 8 bridges needed survey again, and that 139 bridges did not need detail inspection.
Key Words: Tablet computers, brief inspection system, indirect visual, inspection item, detail inspection
Chihiro MACHINAGA In this study, the maintenance bridge of old movable gate dam at Ohkohzu diversion canal, that is used for 80 years over, was examined about damages and bar arrangement, to grasp corrosion and deterioration condition. Damage figures of the maintenance bridge were made with the photographs under the bridge and. Characteristics and tendency of deterioration were grasped through the comparison of each span. As a result, the damage influenced by internal steel frames and steel bars were confirmed regularly. From the past data, main cause of damages under bridge and damages process by comparison were found.
Key Words: steel rein-forced concrete bridge, bar arrangement, corrosion, damage figures, cause of damage
Youhei WASHIO The purpose of this study is to examine tendency of damages with bridges managed by Hokuriku Regional Development Bureau. Conditions of damages and repairing were analyzed on the basis of results of bridge inspected twice, during 2004-2011. Several change patterns of damage were examined in terms of the process of the damage evaluation for targeted bridge. The result suggested that the damages found in the first inspection were becoming worse in the second inspection with high probability. Also, the number of damage was high ratio for the new damages found in the second inspection. Re-deterioration for the bridges that had been already repaired was not found very much.
Key Words: tendency of damages, management, damages patterns, first inspection, second inspection
Takashi KAWAMURA It was important to grasp the behavior of prestressed concrete beam deteriorated by salt damage in static load. In this study, a fiber model by the finite element method software OpenSees was built, and its result was compared with the past experimental data. The result that effect of steel material ruptured and area reduction of cross section by salt damage was confirmed. The rough behavior was reproduced considering the steel break during experiment.
Key Words: prestressed concrete pedestrian bridge, salt damage, finite element method, fiber model, PC reinforcing steel
Ryo KOMAGATA This study target for two PC pedestrian bridge girders with chloride induced determination exposed to chloride contaminated environment for about 35 years. Crack distribution was examined by exterior observation, steel materials corrosion tests and PC steel reinforcement survival tests in previous year. As a result, the correlation between area of crack on haunch part and PC steel reinforcement corrosion rate near surface was relatively high. Also, correlation between the same area and PC steel reinforcement lost rate which was calculate by PC steel reinforcement lost length was as high as previous one. The correlation of reexamined classification of PC steel reinforcement was shown higher than the previous one.
Key Words: Chloride Induce, Prestressed concrete bridge, Crack, PC steel reinforcement, Corrosion
Yusuke NAKAGAWA To clarify purpose the priority of seismic reinforcement and seismic design in accordance with the characteristics of site, the comparison of damage index was done from the seismic response analysis, the earthquake waves made from subject points of 27cities in Niigata prefecture. As a result, damage index was largely affected by ground characteristics, and less effect by original seismic waves. Damage indices were found large when the predominant period of acceleration response spectrums were around 0.2 second. The same result of 17 cities in the eastern Japan were found and seismic reinforcement for the cities to expect high effect should be processed firstly.
Key Words: reinforced concrete piers, seismic design, ductility factor, acceleration response spectrum, ground characteristics
Kento NAKAJIMA Database with 311 bridges inspected two times during 2004 - 09 was made to grasp the bridge deteriorations and damages condition, managed by Hokuriku Regional Development Bureau. Rate of bridge construction before 1960s was large, while the rate of damage built in 1950s〜60s were relatively a little from the point. From the results of change points and rate, deteriorations development of bridges built before 1960s were not found so much, and the one of bridges built 1970s and 1980s were more eminent than the one in others period.
Key Words: bridges, database, management, deteriorations and damages condition, deterioration with year
Yutaro NIWAYAMA In this study, the database was made to accumulate inspection data for bridges, that is possible to input and output with tablet computers. Also the sample data of simple inspection for bridges was input to the database. Damage characteristics were analyzed and considered on the basis of about 130 bridges sample data in Niigata prefecture. As a result, a lot of damages on separation of cover concrete and exposed reinforcing steel bar were found in superstructure of bridge. Also the damage of railing, protection fence, wheel guard and drainage system were found in substructure of bridge. On the whole, some damage bridges were found, but no big problems in the targets.
Key Words: tablet computers, inspection database system for bridges, inspection record, bridge, damage characteristics
Kenta AKAHARA In this study, earthquake input total energy and earthquake input unit energy were calculated with many seismic waves whose scales were amplified or reduced. The quantities of the absorption energy estimated from the relationship between each energy spectrum were compared with the result of elasto-plasticity seismic response analyses by using by two types of equivalent absorption energy which was with or without stiffness after yielding. When earthquake has a clear predominant period and its value was small, it was found that quantities of the absorption energy of RC piers in earthquake could be estimated through the examination of the application of presumption method.
Key Words: Earthquake input total energy, Earthquake input unit energy, Equivalent absorption energy, Energy spectrum, Elasto-plasticity seismic response analysis
Shunsuke SATO Loading tests were performed for two PC pedestrian bridge girders with chloride induced determination exposed to chloride contaminated environment for about 35 years. As the result, Girder A in sea side was broken as shear failure, girder B in mountain side was broken as bending fracture due to the fracture of structural steels unlike design condition. Also, corrosion loss determination and tensile test were performed for structural steels broke out from tear downed girder. Stress at yield nearly equal to tension strength and significant coefficient of extension deterioration were confirmed. Correlative evaluation between failure load and corrosion loss of structural steel near-destroyed area was performed. Structural steel around broken part considered that influenced strength deterioration with corrosion. According to the analysis, strength of PC girder can be evaluated in a way with assuming that broken structural steel has no performance.
Key Words: Chloride Induced Deterioration, Prestressed Concrete Girder, Structual Steel Corrosion, Stress at Yield, Tension Strength
Youhei YAMAI In this study, comparisons of damage index was analyzed with five types of reinforced concrete pier, the probability of earthquake waves considering ground characteristics and the probability of earthquake occurrence. Also the acceleration response spectra were made for each earthquake waves. As a result, damage index was little affected by the difference of pier and seismic waves but largely affected by ground characteristics. When the predominant period of acceleration response spectrums were around 0.2 second, damage indices were large, however, when the period was nearly 0 or the shape of spectrum was similar to terrace, damage indices were found small.
Key Words: seismic risk, acceleration response spectrum, predominant period, ground characteristics, damage index
Masahiro WATANABE A series of static analysis and vibration analysis when walking were performed by finite element method analysis under two conditions for pedestrian bridge made of GFRP used in USA. Costs of members were calculated based on the prices published openly and allowable stress was set by the value of bucking axial force. Eight types of members were considered, and mechanical and economic optimal member arrangement fulfilling conditions of allowable stress and deflection were examined. As a result, the cost of members was calculated 73.0% in the optimal model in a severe condition of allowable stress, and 53.2% in lax condition of allowable stress.
Key Words: Glass fiber reinforced plastics, Finite element method analysis, Static analysis, Vibration analysis when walking, Cost of members, Optimal member arrangement
Ikuma SUGIYAMA In this study, a purpose is identification of need an area appropriate seismic design and seismic reinforcement. Earthquakes were made. Those considered ground characteristics and probability of earthquake. Reinforced piers and unreinforced piers were analyzes by earthquake response analysis, and the purpose aims to accomplishment comparison of damage index. As a result, acceleration response spectrum that has one predominant period has low reinforcement effect. Acceleration response spectrum that has wide range of predominant period has hi reinforcement effect. For this reason, I proved the piers of area that has latter type in the first very effective.
Key Words: earthquake risk, ground characteristics, earthquake response analysis, ductility factor, acceleration response spectrum, excellent period
Ayumu DAIMARU In this study, investigated relation of earthquake input total energy, unit energy, and equivalent absorption energy for simple way of presumption method on construction damage unused Elasto-plastic earthquake response analysis. The result of compared to between presumption value by this way and analytical value by Elasto-plastic response analysis. The simple way in 0.5 less or equal of predominant excellent conjectured earthquake input energy.
Key Words: Earthquake input total energy, Earthquake input unit energy, equivalent absorption energy, Elasto-plastic earthquake response analysis, predominant period
Batjargal Sodbilig This study aims to clarify the behaviors of reinforced concrete beam in static load. A Beam model was built as fiber model, and static analysis was done by Finite element method software, and its result was compared with the past experimental data. Also, an application of the software on damaged beam was examined. Until a yield point, the result of analysis of healthy and damaged beam were almost in accordance with the past experiments. But the result after the yield point of small beam and damaged beam were not matched to past experiments.
Key Words: finite element method, fiber model, reinforced concrete beam, deteriorated beam, static analysis
Ulya Hasanah binti Sahiren Kamal In this study, deformation and cost convert weight were calculated by static analysis with finite element method as for the single material or hybrid materials structure combined the fiber reinforced plastic (FRP) with current steel material (SS400). Based on the price on the market using "Construction Material Price" a calculation was made. As the result, the price of FRP is more expensive than SS400, and from the economical view, using the FRP over SS400 abudantly seems has no merit at all but by minimizing the section area size of FRP, the cost can be reduce.
Key Words: Fiber reinforced plastics, Hybrid material truss bridge, Finite element method, Static analysis, Material price
Yuta KUBOTA In this study, investigated elasto-plastic response analysis by finite element method for finding out the behaviors of RC 2-story viaduct. Both static and dynamic analyses were done with a fiber model of rigid frame structure. The result of these analyses expressed that displacements of analyses were smaller than experimental data. Also dynamic analysis was done with the model for viaduct of Shinkansen.
Key Words: finite element method, FEM fiber model, RC 2-story viaduct, static analysis, dynamic analysis
Takuya SHIRAISHI In this study,to extend the function of database for management of concrete structures. Indicate of map for its computation effects were made. Mark colors could be changed by effects values, indicating the contents of CSV file with coordinate and computation results with Google Maps API and HTML file. For example, Dam map in Niigata prefecture and bridge surface paint damage map were made and it was found that area zoning was cleared such as damage from mark colors of calculated values.
Key Words: concrete structures, management database, Google Maps API, hyper text markup language (HTML) file, comma separated values (CSV) file
Yuichi HIGUCHI This study aims to calcurate maximum velocity of earthquake wave from earthquake occuration risk analysis download from website. in Niigata main city. Result to here after 20% probability in 50 years, Niigata-ken chuetsu earthquake observation of same to earthquake in Nagaoka. So result to predict ductility factor of reinforced concrete pier from earthquake response analysis.
Key Words: ground surface maximum velocity, exceed probability, hazard curve, earthquake response analysis, ductility factor
Ryousuke HIRAKI Simple beam bridge with fiber reinforced plastic (FRP) has already been used, but long span FRP bridge is difficult to construct. In this study the constrain method of response vibration of truss bridge with FRP was proposed by expanding its span, Vibration characteristic by dynamic analyses with the influence of material and cross-section area. As a result, vibration was found to constrain by setting high stiffness material CFRP material with high axial strain energy.
Key Words: fiber reinforced plastic (FRP), truss pedestrian bridge, dynamic analysis, axial strain energy
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