In this research, we proposed the power storage device by energy harvesting from the bridge vibration, for the monitoring system to detect the bridge and predict a tendency toward deterioration of the bridge. We made the prototype monitoring system charging system and verified the operations at the existing bridge. This prototype system demonstrated to measure displacement and temperature at fixed intervals, and the dynamic response of the bridge to passing trains by using only power generated from the bridge vibration.

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In Japan, steel plate bonding method has been widely adopted as a way to reinforce concrete slabs of highway bridges. Usually, the inspection for in the steel plate bonding is performed by a hammering test. However, using the hammering test, quantitative determination of specific damages becomes very difficult. Thus, the development of a new test method is desired. In this study, a laser based method is developed for remote inspection of bonded steel plates. To verify analytically the resonant frequencies of voids, theoretical and FEM analysis solutions are compared. Some results obtained from laboratory measurement of specimens are also compared with numerical solutions. Results showed that the laser based method has a promising possibility to become an effective nondestructive evaluation method for steel plate bonding of highway bridges.

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The aim of this study is to figure out an effect of chrolide on film performance with on-site painting of steel road bridges. A trial painting of an actual-size steel girder was conducted under high-salinity environment in order to investigate the amount of deposited chrolide on the coated surface between the painting processes. In addition, we examined delamination strength and dulability of the coating system which was intentionally-attached chrolide between the film layers in laboratory experiments. As the results, it was shown that more than 150-200 mg/m² of chrolide can reduce the interlayer adhesion strengh and deteriorate early protective performance of the coating system.

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A resin has been filled into the clearance between bolt and bolt hole in bolted connection of timber member to prevent a backlash by the clearance, and we have proved that the resin improve a performance of the bolted connection. However, stress concentration occurred by bolt bending at both sides of bolt hole in the case of resin type was remarkably higher than driven type. Furthermore, bolts have been set at the center of the bolt hole in these tests, but it was difficult to put the bolt on the center of bolt hole in construction. In this paper, we proposed tapered hole that was made at both end of bolt hole to relax the stress concentration. As a result, the effect of the resin was improved more by making taper and the concern for the position gap of the bolt was wiped out.

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While FEM is needed to evaluate the behavior of the on-site timber stress-laminated box-beam bridges, whose shear deformation can be significantly large, it is very difficult to model the detail parts such as prestressed connection, holes in plates, diaphragms and so on. Firstly, we compare the exact FEM calculations considering the influence of the prestress by the contact problem to the simpler FEM calculations neglecting the prestress by the shared nodes at the adjacent planes between members. Secondly, we compare the simpler FEM calculations and Timoshenko's beam theory with some trial shear coefficients to the experimental results. As a result we conclude that Timoshenko's beam theory can be good approximation within possible cross-section range for the types of timber box-beam bridges.

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The history of modern timber bridges is about 30 years in our country, and maintenance method of the bridges is being improved. However, the actual condition is that the investigation on durable years for modern timber bridges is hardly done also in foreign countries in addition to the timber bridge research subcommittee in JSCE. In this study, the analysis of factor on durable years and the estimation by qualification theory class I are performed using data of 72 bridges, and then the estimated equation of durable years for modern timber bridges is examined. Furthermore, the application method of the estimated equation is shown.

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The high strength bolted frictional joints are frequently used for repair and strengthening works of steel bridges, such as patch plates with epoxy resin. In order to investigate the retrofit effect of adhesive patch plate which are bolted by high tension bolts to the corroded steel member, tensile tests which are the length of patch plate or the number of bolts as a parameter are conducted. Based on the tensile tests, it is found that if patch plate satisfies its length and thickness, the deterioration of stiffness and capacity of specimens is not observed.

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High strength bolted friction type joints are often used on steel bridge. On the other hand, the number of rows of bolts has tended to increase as a result of the thicker steel plate. In addition, corrosion is actualizing on the existing bridge on the bolted joints. In response to this problem, the authors have investigated the use of thermal spraying for the surfaces in order to achieve a high slip coefficient. In this study, we have performed on the tensile tests in order to examine the effect of the slip resistance with metallic thermal spraying surface coating on one side. It was concluded from the experimental result that the slip coefficient of the surface coating is about 10% higher than inorganic zinc paint on both sides and its slip coefficient depends on the destruction Mechanism.

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Assembly tolerance of members of a structure causes eccentricity of an axial line of the member. In the case that the members is high strength bolted friction type joint, one of the assembly tolerances is an irregularity of connected plates in lateral direction. This paper evaluates the effect of the irregularity of connected plates of the joint to its slip strength. The strength is evaluated by FEM analysis. Behavior of bolt tightening and the slip strength of joints whose connected surface attached closely or attached with interspace is compared and discussed.

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One of the methods of connecting steel members is a screw. Since screws do not use nuts, it can work from one side. By the way, there is a screw called a thread forming screw. It is a screw itself fabricates an internal thread to steel members, and it connects members. No research on strength of joints connected with thread forming screws in the field of steel structures of civil engineering has been reported, as far as an author gets to know. In this paper, the static tensile strength of the tensile joints connected with the thread forming screw is first investigated. Next, the static tensile strength and fatigue strength of lap joints connected with the thread forming screw are investigated. Finally, fatigue strength of joints in case a thread forming screw does not penetrate steel members is investigated.

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The impact crack closure retrofit treatment (called ICR treatment) is a technique to delay or arrest fatigue crack growth and enhance residual fatigue life of weld joints including a crack. The treatment is carried out with an air tool to peen plate near the crack and to produce plastic deformation of the steel surface in order to close crack opening. In this study, several fatigue tests on weld joints were conducted under tensile or bending loads in order to verify the life extension effect by ICR treatment. Besides, the effect of the loading types to the life extension was analytically investigated.

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It is well known that the fatigue strength of weld toe can be improved by peening which introduces the compressive stress. However, when the compressive over load (OL) is subjected after peening, the compressive stress of welded toe is released and effect of improvement of fatigue strength becomes small. In the previous research, the authors carried out fatigue tests of out-of-plane gusset joint and clarified that the improved fatigue strength is reduced by subjected the compressive OL. In this paper, to evaluate the reduction of improved fatigue strength by the compressive OL, fatigue tests of T-joint were carried out. Furthermore, fatigue strengths of out-of-plane gusset joint and T-joint subjected compression OL after peening were estimated by using the elasto-plastic large deformation analysis and the modified Goodman Diagrams.

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Scallops are generally set on lateral gusset plates connected to webs of steel I-section girder bridges in order to avoid intersection of weld lines. The gussets are subjected to stresses by sectional forces in lateral bracing, sway bracing and cross beam in addition to main girder. Therefore, stress distribution is complex in the gusset scallop. In actual bridges, fatigue cracks were found at the boxing weld toe in the end of gussets and boxing weld toe at inner of scallops. In this study, FE analysis has been performed to make clear the stress behavior of lateral gusset plate. Then in comparison with the result of the normal fatigue design, and confirmed the structure improvement effect.

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This paper presents an assessment method for extremely low cycle fatigue cracks from corner joints in concrete-filled steel piers. Low cycle fatigue tests indicated that one of the main failure modes of concrete-filled steel piers are a fatigue crack from corner joints, which is caused by out-of-plane bending deformation of flange and web plates. In the previous study, authors had proposed extremely low cycle fatigue strength curves for the corner joints based on the effective notch strain approach. In this study, the proposed method was applied to the experiment of the concrete-filled piers and it is demonstrated that extremely low cycle fatigue life of the pier can be predicted by using the method.

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RC specimens using reactive aggregates have been carried out for a long-term exposure test over about 5 years at outdoor environment. After 1850 days of exposure, fracture in bended part of stirrup is reproduced. In this paper, the authors mainly evaluate the external and internal deteriorations near the fracture position. It is known that restraint for expansive force is reduced due to the fracture of stirrup. Thus, it is found that the external crack width near the fracture location has an intense increase; while a great crack is confirmed to spread from the center of concrete to the exterior of surface and cut throughout the fracture location.

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Using specimens, in which expansive mortar is cast, experimental tests are performed to simulate the stirrup fractures due to ASR expansion. The time variation of external degradation and its connection to movement of stirrup is studied. The specimens, with greater deformation around 8.0mm in central profile have reproduced the ASR-induced circular deformation. Cracks in external concrete are divided into non-throughout crack due to bending effect and throughout crack from uniform tension and shear. For checking the influence on movement of stirrup from circular deformation, stirrup shapes before and after expansion are recorded. The bended part of stirrups is verified to have opening deformation with angular increment 1.62°. Due to the opening deformation, crack ratio in stirrups is confirmed to progress from initial 2.56% to 17.70% after expansion.

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Many Reinforced Concrete (RC) piers of Hanshin Expressway have been damaged by Alkali Silica Reaction (ASR). Hanshin expressway has repaired these piers by bonding steel plates. In this study, the load resistant capacity for RC beam affected by ASR and repaired beam by steel-plate-bonding by using 3-Dimensional non-linear Finite Element Method analysis (3D FEM). In this analysis, the influence of ASR on the load resisting mechanism or capacity was clarified by using 3D FEM that modeled the each physical phenomenon such as the degradation of adhesion between steel plate and concrete, elastic coefficient of concrete and the fracture of reinforcing bar. Furthermore, the repair effect of RC pier cap by using steel-plate-bonding method is also evaluated by the 3D FEM, considering the steel plates and epoxy resin elements.

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The behaviors of corrosion-induced concrete cover spalling were investigated experimentally and analytically, with a specific emphasis on the local corrosion along the rebar. In the experiments, the single rebar embedded in a slab specimen was corroded non-uniformly in the length direction by an electric corrosion method. The cracking behavior including surface and internal crack patterns were observed. In the analysis, the three-dimensional Rigid Body Spring Method (RBSM) combined with the corrosion expansion model was applied to examine the cracks propagation that induces the cover spalling when rebar subjected to the non-uniform corrosion distribution. Both experimental and analytical results showed that the internal crack pattern differs along the rebar length, depending on the corrosion distribution. The concentrated corrosion would cause inclined lateral cracks to the concrete surface in addition to the vertical crack, which triggers the cover spalling, while only vertical cracks appear at the external areas.

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A shear failure of RC beam with repaired honeycombing in the bottom of the beam was examined. The beam specimens were repaired by conventional or proposed method. In the loading tests, peeling at the repaired interface was observed in the conventional methods. Without anchorages, diagonal cracks easily occurred from the end of the interface and the shear strength was decreased. However, with anchorages at the interface, the repaired beam was not suddenly failed after the peeling and the shear strength was almost equivalent to that of the sound concrete specimen. The beam specimen repaired by the proposed method did not show the peeling at the interface until failure, and then it provided the almost same shear strength as the sound beam.

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In this study, the effect of shearing capacity of RC beams with haunch by PCM shotcrete method with CFRP grid was examined. It was carried out by 2 series experiments. Series A was 2 standards as a parameter with the reinforced range of CFRP grid, and Series B was 3 standards as a parameter with the reinforced quantity of CFRP grid. It was obtained that in reinforced beam which was reinforced by PCM and CFRP grid fixed with web and haunch, the integrity of the reinforced section and the existed section was good and the reinforced effect was sufficient.

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Shear stress transfer model of concrete was evaluated by considering the characteristics of cracked surface as parameters, which are the shape and asperity height. The parameters in the proposed shear stress transfer model were identified by using experimental results of plain concrete specimens. The reasonable agreements between the calculated results and the experimental ones on element level were confirmed. In addition, the applicability of proposed shear stress transfer model in structural level was verified. From the results, it was shown that the model could predict the behavior of RC members failed in shear using not only normal strength concrete, but also high strength concrete and light weight aggregate concrete.

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To evaluate mechanisms of residual displacement, dynamic analysis was conducted for a full scale RC column (C1-1) by shake table test, using detailed property of movable bearing based on element test. Analytical result generally correlated well with experimental result, especially the residual displacement in LG direction. Frictional force of movable bearing caused notable residual horizontal load on column top. This residual load mainly led to the noticeable residual displacement. Furthermore, the friction-free assumption according to specification might not be safe, because the residual displacement would be underestimated significantly.

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It is known that the fatigue resistance of concrete decreases when it becomes saturated with water, and that its compressive strength increases at low temperature. However, there have been few systematic investigations of the influence of the environmental temperature and moisture conditions on the fatigue resistance of concrete. In the present study, static loading and fatigue tests were carried out on concrete cylinders to determine their fatigue resistance under compression. The results indicated that at room temperature, the static compressive strength decreased with increasing moisture content. In contrast, at low temperature, it increased with increasing moisture content. On the other hand, regardless of the temperature, the fatigue resistance decreased as the moisture content increased.

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This study proposed a local strain based fatigue strength evaluation method for deformed bars in low cycle fatigue region. Fatigue tests were conducted with the bars which have different yield strength and transverse rib shapes. The results indicated that low cycle fatigue strength of the deformed bars is almost the same regardless of the yield strength but it depends on the rib shapes. This is because strain concentration at the rib changes due to its shape. Finally, this study demonstrated that the fatigue strength of the bars with different rib shapes can be uniquely evaluated by considering local strain at the rib.

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In this study, the fatigue damage levels of practical RC road bridge decks was evaluated focusing on the decline of resonance frequency by forced vibration test. The bridge decks were replaced after being in service for 50 years because it showed serious damages due to heavy traffic loads and deicing salts. First, the conditions of deterioration in the cutting cross section and the lower surface of specimens sampled from the decks were observed. Then, the relationship between the degradation of resonant frequency at respective point of specimen and the fatigue process by wheel load trucking test was investigated. As a result, it was revealed that the decline of resonance frequency could make it possible to evaluate fatigue damage levels depending on internal cracks of bridge deck.

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The precast slab with the void part for stud arrangement is sometimes used in exchanging the RC slab due to shortening of a construction period and arrangement of shear connectors. Then, it is required to investigate the composite action between the steel girder and the precast slab with the grouped studs in detail, and the effect of installing the precast slab partially. In this study, we conducted the composite girder test having the precast slab with the grouped studs and the one having the RC slab with the normal stud arrangement. As a result, the static behavior are compared between both composite girders and the corresponding push-out specimens, and the composite action of the girder with the precast slab is clarified in detail.

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Shear deformation of CFRP affects how the force transfers from a steel plate to a CFRP plate in a CFRP bonded steel plate under an axial force. A widely accepted shear lag theory to model a CFRP bonded steel plate does not usually consider the effect of shear deformation in the CFRP plate. This study proposes a way to account for the effect of shear deformation in the CFRP plate on the force transfer between steel and CFRP by increasing the thickness of adhesive layer in the conventional shear lag theory.

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In steel members bonded with carbon-fiber reinforced polymer (CFRP) plate, the thermal stresses are introduced in the steel members, the CFRP plates and the adhesive layers when temperature changes because the linear thermal expansion coefficients of steel and CFRP are mismatched. In the previous paper, the authors proposed a technique to reduce thermal stress in steel members strengthened by CFRP plate, which involves bonding aluminum alloy plates with CFRP plates. In this research, the thermal stress introduced in the steel plate with CFRP and aluminum plates was measured over one year. As the result, it was shown the thermal stress in steel plate was neglectable small through the all-season. Additionally, a steel plate bonded carbon fiber strand sheets and aluminium plates side by side was tested. In this method, the thermal stress induced in steel plate was also reduced.

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In this research, to study the thermal behavior such as thermal stress and deformation of composite bridges with a SRC structure, a field measurement and a FE analysis were carried out for the composite trussed rohze bridge constructed by using weathering steel. In the field test, the temperatures of the surface on the bridge members were measured by an infrared camera. And then, FE analysis model was constructed by the temperature data of the field test, and FE analysis was carried out to investigate the thermal stress and deformation due to changing the thermal condition. The field test showed the value of measured temperature difference was higher than the design value. FE analysis indicated the bridge members under the dead, live and thermal load suffered under the influence of the thermal stress.

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Composite bridge pier consisting of steel pipes with external ribs and concrete can reduce construction-work by replacing a part of reinforcing bars with steel pipes. In order to evaluate seismic performance of this structure, the cyclic loading tests was carried out on a specimen which were scaled down as possible exactly .As the results, the relation between load-displacement curve and progression of the damage of bridge pier were revealed, furthermore decreasing of energy absorption and plastic hinge length, transition of longitudinal re-bars strain were verified. From these results, we showed the validity of the limit displacement method for evaluating the seismic performance of this composite bridge pier.

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This paper deals with a two-layered pipe rehabilitation method made of a PVC pipe and a spiral FRP. First, flattening tests were simulated by contact analysis of FEA considering interaction between layers. It was confirmed that the contact analysis successfully simulated the test. Then acceptable thickness of PVC and FRP which meets design criteria was calculated by the contact analysis, and the results were compared with those by the design equations assuming the independency and uniformity between layers. The results of the contact analysis were similar to the results by the design equation assuming the indepenency of layers, and the required thickness by the contact analysis is 1mm thinner than that by the design equation assuming the independency of layers.

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Our civil engineers should be obliged to present a technological methods and guidance on how to design structures to resist severe earthquake attacks. It has been known that polyurea resin coating techniques is highly effective to strengthen RC structures against explosive events. Their fast reactivity and relative insensitivity to moisture make them useful coatings for large surface area projects, such as secondary containment, tunnel coatings, tank liners, and other structural components. To break a fresh method for retrofitting RC structures, this study is to find experimentally the retrofitting effects by polyurea resin coating of steel can. In drop impact tests, thin steel cans with different coating thicknesses are tested under various conditions. From test results, it is cleared that an impact resistance by polyurea coating can be remarkably improved.

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How to design structures to resist severe earthquake attacks is one of the challenges today for our civil engineers, and then we should be obliged to present a technological methods and guidance. A polyurea resin coating techniques has been known that it has effectiveness to strengthen RC structures against impact and explosive events. To break a fresh method for retrofitting RC structures, this study is to find experimentally the retrofitting effects by polyurea resin coating of plate/wall members. In horizontal impact tests, various plate/wall members with different coating thicknesses are tested. From test results, it is found that an impact resistance by polyurea coating can be remarkably improved.

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Sand cushion materials laid on rock sheds present unresolved problems. An important solution to such issues is enabling a comprehensive understanding of the deformation mechanism of sand cushion. In this study, we analyzed a large-scale test and a drop test for a square block-type sand model by ground density examination, with focus on variations in sand cushion density. During the examination, the internal components of the sand cushion with 80% density loosened. By image processing, we visualized the density variations in a model test, through which we determined the range of impact force influence and the localization of expansion and compression. Finally, we visualized the stress distribution at the bottom of the sand cushion with a pressure-sensitive sheet.

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Cushioning materials, such as sand cushion and granular mats placed on rock sheds, can effectively disperse and reduce rock fall energy before rocks collide with protection works. To elucidate the cushioning mechanism of cushioning materials, particularly sand cushion, this study examines the manner by which impact force is transmitted in a sand mat in case of different external force and sand cushion thickness. The results obtained are summarized as follows: (1) The maximum transfer impact force increases the duration of rockfall impact force; (2) changes in the ratio of transmitted impact force and rockfall impact force by external force conditions and sand cushion conditions are reflected by stress propagation behavior and the duration time of rockfall impact force.

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This study proposed an evaluating method of the risk of a RC structure when explosive incidents occured. As a hazard curve, the relationship between explosive quantity and frequency of the explosive incident was evaluated based on the statistics of terrorist's bombings in the world. In order to evaluate a fragility curve based on calculation of dynamic response, members of the RC structure, i.e. beam, column, slab, window, were modeled as a single degree of freedom model. Total probability of failure of the RC structure was estimated by superposing the fragility curve of the members. Losses of the RC building and people were calculated based on the damage states of the RC building. A risk curve was evaluated based on the hazard and loss curves.

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This study presents local damage resistant performance of fiber reinforced cementitious composite plates including polyvinyl alcohol short fibers subjected to high velocity impact by a steel projectile. Effects of mixing ratio of the short fibers were examined by conducting high velocity impact tests. It was observed from the impact tests that the local damage was suppressed efficiently as the mixing ratio of the short fibers increased. The reinforcing effects were discussed based on the penetration depth and scabbing limit thickeness. An estimating method of the penetration and scabbing limit thicknesses was proposed with reduction factors multiplied by the modified NDRC formula.

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This paper presents a distinct element method which evaluates impact load of the debris flow on steel frame check dam. The proposed method expresses the debris flow and the permeable body of check dam by coupled analysis of the proposed spherical water elements and the spherical solid elements. Debris flow and water flow with various parameters hit on the structure, and time history of the load are measured in the experiments. The method applied to simulate experimental results carried out to estimate time history of the load in analysis. The simulation results show in good agreement with the experimental ones.

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This paper presents an experimental study on woody debris positioning in water flow surge by using rolling cylinder experiment device. First, the surge shape of water flow is examined under various amount of water and revolving speed. Second, the surge shape of woody debris flow is examined to confirm woody accumulation at front part of water surge. Comparing each other, the effect of woody debris containment on the surge shape of debris flow is discussed.

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In this paper, in order to establish a rational impact response analysis method of the RC rockfall protection galleries, elasto-plastic response analyses of a full-scale gallery with sand cushion under falling weight impact loading were conducted. Here, a new constitutive model for sand cushion was proposed, which was modified by adding the initial stiffness and yield plateau to a previous model. An applicability of the proposed model and analysis method were investigated comparing with the experimental results. From this study, it was seen that applying the proposed cushion model and analysis method, the dynamic response behavior of the gallery can be accurately predicted irrespective of the magnitude of the impact energy.

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The authors have developed a constitutive model of the three dimensional Rigid-Body-Spring Model with random geometry for quantitative evaluation of the softening and localization of concrete subjected to lateral pressure and uniaxial compression. In the present study, numerical simulations of concrete plates subjected to high velocity impact using the proposed model were conducted for validation of the applicability to the evaluation of the local damage subjected to impact loads. By comparing numerical results with the experimental results, we confirmed that the proposed model can reasonably evaluate the local damage of concrete plates. In addition, the crack propagation behavior and the stress transfer mechanism of local damage were discussed.

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This study presents applicability of the absorbed energy evaluation method for a high-strength wire net of different shapes to be used for tornado missile protection equipments. The dynamic load-deformation relationship of high strength wire net of 40mm mesh and 50mm mesh were obtained by dynamic tensile tests. In order to confirm energy absorption ability of the net, free drop impact tests with heavy object were conducted. It was cleared that the absorbed energy of the net had to be calculated as square of dimensions long when ratio of length to width was less than 1 and the method was available if the aspect ratio were less than 2. As a result, it is found that the proposed evaluation method could estimate energy absorption ability of wire nets of different shapes by considering the limited conditions mentioned above.

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Maweihe Bridge is a skew bridge damaged in Wenchuan earthquake on May 12th, 2008. Serious damage has been found at abutment and side blocks. Pounding induced damage has been discussed. In order to make clear the pounding procedure, dynamic analysis for the superstructure was conducted. Based on the theoretical formula about momentum and impulse, the affected factors on pounding force have been discussed. Pounding velocity and rotational angel have been regarded as the determining factors of pounding force. The improving measures of bridge structure can be conducted to reduce the pounding force.

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In this study, in order to investigate the impact resistant behavior of PC beams and to develop an effective flexurally reinforcing method for those, falling-weight impact tests of the flexurally reinforced T-shaped PC beams with AFRP sheet were conducted taking with/without bonding FRP sheet, loading method (static and impact loading), and impact velocity as experimental variables. From this study, the following results were obtained: 1) the PC beams suffered by tendon yielding tend to be collapsed easily with slightly increasing impact energy; 2) the deflection of the PC beams can be restrained due to flexurally reinforcing with AFRP sheet; and 3) the AFRP sheet was debonded due to the peeling action of the critical diagonal crack developed in the lower concrete cover near the loading points, irrespective of the loading method.

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To develop the rational strengthening method for improving the impact resistant capacity of RC beam damaged due to impact loading, falling weight impact tests of RC beams flexurally strengthened with Aramid Fiber Reinforced Polymer (AFRP) sheet were conducted. Experimental parameters of this study are with/without damage due to impact loading, AFRP sheet volume, and falling height of the weight. From this study, following results were obtained: 1) strengthening effects of AFRP sheet bonding on impact resistantcapacity of the damaged RC beams were almost the same with the case of not-damaged RC beam; 2) the greater the volume of AFRP sheet is, the more restrained the deflection can be; and 3) AFRP sheet may be ruptured due to stress concentration caused by occurring and opening of cracks.

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In this paper, to investigate the absorbing effects of a new absorbing system by means of Geocell filled with one-size aggregate, the impact loading tests of the new system were conducted. Here, to measure the transmitted impact stresses, total 24 load-cells were embedded in the rigid wall behind the new system. The high speed camera was also used to precisely record the impact resistant behaviors of the system. From this study, the following results were obtained: (1) maximum impact force can be better evaluated by means of Hertz contact theory with Lame's constant λ = 1,500 kN/m²; and (2) transmitted stress was distributed within both sides of 1,000 mm in the horizontal direction from impact loading point and the maximum transmitted stress was developed at a slightly lower position from the loading point.

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In order to establish a performance-based impact resistant design procedure for rockfall protection galleries, falling-weight impact tests of a full-scale gallery specimen were conducted for the cases of using sand and gravel cushions. The gallery specimen was designed based on the allowable stress design procedure for an input impact energy of E = 100 kJ following Japanese design guideline. From this study, following results were obtained: 1) the absorbing performance of the sand cushion was higher than that of gravel one, when the input impact energy was fifteen times greater than the design value; and 2) for both sand and gravel cushions, the gallery specimen was still in the elastic (cracked) state, i.e. serviceability limit state.

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In this study, to establish a simple and rational numerical analysis procedure of RC rock-shed for practical design use, three dimensional dynamic frame analysis of full-scale rock-shed with TLAS was performed. An applicability of proposed analysis method was verified by comparing experimental results, such as distributions of bending moment and displacement. As a results, it was confirmed that since the impact response behavior of rock-shed can be precisely estimated by applying the proposed analysis method, it was effective tool for practical design use of rock-shed.

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In this study, in order to investigate the safety margin of sectional forces estimated by means of existing impact resistant design method for rockfall protection gallery, the sectional forces obtained based on the existing allowable stress design specifications were compared with those obtained from the full-scale falling-weight impact test of a rockfall protection gallery. From this study, following results were obtained: 1) design values for sectional bending moment were greater than those from the experimental results, irrespective of cushion materials (sand and/or gravel) and the location of impacted point; and 2) safety margin of the load-carrying capacity for roof slab was smaller than that for column and wall.

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In this paper OMNIBUS method is developed by organizing each property of harmonic analysis, STRIP method and point matching method. Through examples of multi-layered slab that is simply supported with all edges, and that the fourth side only is given by fixed condition, validity of this method is investigated from comparisons of classical solutions. Numerical examples by this method and STRIP method respectively are shown in cases of that multi-layered slab composed of different span length with free edge is subjected to partially loading, and further same slab has partially loose zone under local loading.

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