This study aimed at developing a gaze allocation data feedback system for conducting driving simulator training using quantitative gaze data of train drivers. The system can preset driving scenes to efficiently instruct trainees within a limited training time. The system can also compare trainees with experts using face direction data and gaze target data graphs to clarify the characteristics of trainee allocation of visual attention. In addition, the system can visualize the gaze allocation data and clearly show the objects that trainees were looking at while driving a simulator. Instructors from a railway company tested the system and gave a positive evaluation of it as a training tool for trainee visual attention.

In the verification of reinforced concrete (RC) piles, the design shear capacity V_yd of linear members is used based on the experimental results of simply supported RC beams. On the other hand, since RC piles are subjected to ground reaction forces, the shear capacity may be greater than V_yd, unlike simply supported conditions. In this paper, we have used nonlinear finite element analysis to evaluate the shear capacity of RC pile heads taking into account ground reaction forces. We have shown that the equivalent shear span method, which is applied to the analysis of slabs of underground box structures, can also be applied to the analysis of RC pile heads.

In this study, the effect of snow cover on slope stability was examined to more accurately evaluate the risk of snowmelt hazards. Firstly, laboratory tests were carried out to determine strength characteristics of snow. In addition to laboratory tests, sprinkling model experiments were conducted on a snow-covered embankment model to observe the moisture response and deformation of the embankment. In addition, slope stability analysis using a finite element method was carried out on the snow-covered embankment model. The result confirmed that snow cover could restrict the surface layer of an embankment and slightly improve the slope stability.

A Non-linear Response Spectrum Method is one of the methods used to calculate the seismic response values of railway bridges and viaducts. In this study, a method for expressing the non-linear response spectrum is proposed using a relatively simple mathematical equation. In addition, a procedure for estimating the parameters for the equation is proposed. The proposed method was applied to seismic records, and results confirmed that the proposed method can automatically represent the overall trend of the spectra of seismic records while significantly reducing the number of parameters used compared to conventional methods.

Since the stability of railway embankments damaged by rainfall is not easy to assess, the need for temporary restoration is often determined on the strength of experience of inspectors, or the damaged embankment is restored to its original shape. As a result, there are cases where temporary restorations are carried out with specifications which exceed what is required for embankments that already meet performance requirements for train operation. This study proposes a method for evaluating the performance of damaged embankments or temporary restoration embankments in terms of stability and settlement during train operation, and to quickly determine whether train operations can be resumed on a damaged embankment.

To reduce wear of current collecting materials such as contact wires and contact strips on electric railways, it is necessary to clarify the wear mechanism, especially mechanical wear due to frictional heat. In this study, the authors carried out wear tests using a new rotary wear tester capable of measuring the contact temperature and analyzed the temperature rise using a new contact model that takes into account the number of contacts. From the test and analysis results, the authors classified wear modes into four types based on the softening of materials and clarified that the seizure wear mode occurs when the contact pressure exceeds the hardness of the material.

Rail fastening systems using bolts and leaf spring clips are widely used in Japan. This rail fastening system requires regular maintenance to prevent the bolts from loosening. To eliminate the need for retightening bolts, some railway companies are replacing rail fastening systems using leaf spring clips with boltless rail fastening systems using round bar clips. This replacement involves replacing the existing PC sleepers with another type of sleepers for round bar clips. Therefore, some railway companies find it difficult to introduce boltless rail fastening systems using round bar spring clips due to construction costs and labor. In response to this problem, we have developed non-loosening rail fastening systems using leaf spring clips that are compatible with existing PC sleepers.

In order to reduce the bulge of gas pressure welding and finish by grinding only, the authors carried out rail gas pressure welding tests and numerical analysis to reduce the upset distance. In the tests, a new rail gas pressure welding method using a variable pressure method was achieved with a compression of the upset distance of about 6 mm, which is 1/4 of the conventional method, with sufficient strength for practical use. As the trimming process is not necessary, there is no need for a trimming device. This also reduces the weight of gas pressure rail welding machines.

It is impractical to conduct collision tests with an actual train unit to design crash safety structures. Numerical simulation is effective, but it is important to validate its analytical accuracy. Therefore, the authors conducted a collision test of a full-scale partial stainless steel carbody structure of railway vehicle's lead car and a typical large dump truck. In addition to the test, FE analysis was conducted under the same conditions as the experimental test in order to compare numerical and experimental results, and this obtained agreement between both sets of results. Finally, using the FE analysis, the authors estimated the impact deformation and fracture behavior of the railway carbody under the actual level-crossing accident.

Aerodynamic noise radiated from high-speed trains in operation is attracting attention from an environmental point of view. Bogie areas are known to be the main sources of the aerodynamic noise. Rounding the four corners of the bogie cavity has been proposed as a measure to reduce bogie aerodynamic noise, and wind tunnel tests have confirmed its effectiveness. However, detailed flow fields around the bogie area have not been identified and the mechanism of noise reduction by such measures remains unclear. In this study, numerical analyses of the flow field in the vicinity of the bogie area were carried out to investigate the changes in the flow field caused by the proposed measure and to discuss the reduction mechanism.

Reducing aerodynamic noise emitted by pantographs is one of the key challenges to be overcome to reduce the environmental impact of railways and enable faster train running speeds. Previous studies proposed a method for reducing aerodynamic noise by applying porous material to pantograph head support covers. This study proposes a new practical method to achieve the same aerodynamic noise reduction effect as using porous material. Wind tunnel test results showed that this new method can reduce aerodynamic noise to almost the same extent as using porous material.