Abstract: Twelve transmission shafts were developed unilateralism torsion fatigue tests.
Macroscopic and microscopic fracture features of transmission shafts were observed and analyzed.
No defect was found in the origin which was usually located at the bolt bores or nearby the bolt
bores because of the stress concentration. Using the fractography quantitative analysis technology
the propagation life, the origination life and the relation curve between the crack length and the
cycle numbers for all of the twelve shafts were estimated. For only one origin on the fracture
surface the total life of the shaft with two expanding directions is usually obvious longer than that
with one expanding direction, but the main propagation life is obvious smaller. However for two
origins and two expanding directions on the fracture surface the total life of the shaft is usually
Abstract: Wavelet denoising method was introduced to improve the validity of identifying the guide
rail irregularity in elevator. The horizontal acceleration signal measured from a test elevator was
processed by wavelet denoising. Then the denoised signal was decomposed up to four levels using
Daubechies 4 mother wavelet to identify the guide rail irregularity. The results indicate that the
impulses due to the guide rail irregularity are prominent in wavelet decompositions. And the causes
resulting in those characteristics of the vibration signal can be well revealed. So discrete wavelet
transform (DWT) can be used as an effective tool for denoising the horizontal vibration signal of
elevator and diagnosing faults in the guide rail.
Abstract: An enhancement to pre & post processing techniques, which is encapsulated in ‘Tunnel
Modelling Wizard (TMW)’ for three dimensional tunnel analysis, is developed and described in this
paper. The techniques include geometry modelling, mesh generation, virtual transformation, flying
view and utilization and interpretation of analysis results. The TMW automatically generates full
analysis data including mesh, loads, boundary conditions and construction stages from the
user-defined parameters. The TMW also provides its own file I/O service to help users expedite
modelling tasks for similar models and build their own tunnel templates. Implementation of the TMW
into a FE Program is described, and applications of the TMW to practical tunnel problems will be
Abstract: This paper represents the development of 3-axises loadcell for measuring the side-force of
the suspension module of MPV (Multi Purposed Vehicle). The side force causes the failure of damper,
such as leakage. The loadcell was developed using strain gauges, and the Wheastone bridge circuit to
compensate for the cross-talk between each axises and the measurement error by temperature.
Structure analysis of loadcell was accomplished with FEM (Finite Element Method) to optimize the
location of strain gages. The design optimization for the important factors that have effects on
performance of loadcell was accomplished by using DOE (Design of Experiment). Loadcell was
produced and successfully tested, showing good sensitivity and low cross-talk. The cross-talk of the
developed loadcell is below 2%. The measured history using the manufactured load cell will be
utilized in the vibration, and fatigue analysis in the future.
Abstract: In order to establish a reasonable and integrated fatigue design criterion for the long life
design of the gas welded body structure, stress distribution around the gas welded joints subjected
to tensile load was numerically analyzed. And also, the P-Nf curves were obtained by fatigue tests.
By using these results, P-Nf curves were rearranged in the σ-Nf relation with the hot spot stress at
the welded joint. And a guideline for fatigue design of gas welded joints was proposed.
Abstract: In order to develop a fatigue design method for the actual railroad car body structures
using the fatigue data on simulated single spot welded lap joints, firstly, evaluated fatigue strength
on the spot welded t-type member which is a component of the actual railroad car body structure.
And next, possibility of fatigue design for spot welded T-type member using the fatigue data of
single spot welded lap joints was investigated. From the results, it was found that, even though there
is some difference in fatigue strength between single spot welded joint and the actual members
under the same fatigue life, the fatigue design criterion could be predicted by correction between
Abstract: This paper describes a primary study for a new method of enhancing measurement with
using an impedance analysis method that is applied to structural health monitoring. The goal of this
research is to show basic information that is used to evaluate the structural health condition with
using piezoelectric sensors. We present a study for the development of a practical and quantitative
technique for the assessment of the structural health condition with using a piezoelectric
impedance-based technique that is associated with longitudinal wave propagation. The natural
frequency has a tendency of frequency shifting with respect to the hole size that corresponds to the
real structure’s crack size. To numerically estimate the damage condition, we suggest the Cov
(Covariance) and CC (Correlation Coefficient) evaluation methods.
Abstract: In the study, the development of aerial platform truck of 42m boom system has been
completed to be satisfied with working in much higher place. To avoid the rollover accident of
vehicles while working, 3D FEA is applied to verify the 3D design, stress concentration, stress
distribution, deflection, natural frequencies etc. In these analyses, traction load of Boom System,
700 Kg and traction degree analyzed to 0° ~ 85°. Analysis result, when Boom System's angle is 0°,
could know that stress concentration and deflection are obtained to maximum. We could predict that
maximum point of Stress concentration is 3.275 as safety factor and deflection of Boom system end
part is max. 78.5Cm. Also could know that natural frequency and mode shape of boom system are
stable in correlation with aerial platform truck's operation area. With these results, the structural
stability of boom system in 42m aerial platform truck is obtained, then finally trying to find an
optimum design of aerial platform truck.
Abstract: In this study, finite element analyses for the mechanical behaviors of a power steering hose
assembly during the swaging process were performed in order to investigate the stress level of hose
components according to jaw strokes, and to examine the effect of friction coefficient on the contact
force. The physical properties such as Mooney-Rivlin constants of rubber materials and the
work-hardening data of the steel were obtained through the experiments, and the contact conditions
identical to the swaging process were taken into account. Two reinforced layers included in the hose
were modeled with axisymmetric rebar elements in the general-purpose program, MSC MARC2000.
The updated Lagrange formulation and the large displacement option were employed in the analysis.
The result interpretations were focused on the rubber components which are in contact with the metal
components, because of their important roles in the hose efficiency.
Abstract: This paper describes codes and practice for designing welded structures such as railroad
truck frames. For designing an initial configuration, rather simple criteria are desired, although most
codes such as AWS, AISC, etc. are complex. They consist of a variety of welded joint categories,
which make a designer feel difficult when deciding the initial configuration. Therefore, such codes
are considered to be mainly used for the evaluation of designed and constructed structures, and not
to be used for deciding the initial configuration. The JIS (Japanese Industrial Standard) for a railroad
truck frame is explained as an example of a simple code, and is compared with some fatigue data.
This standard is thought to be useful for a designer. However, the result of this investigation
suggests a modification of the JIS for obtaining more reasonable criteria.
Desirable criteria should be simple for a designer and sufficiently safe for structures. Additional
fatigue data of welded joints, a statistical study for desirable non-fracture probability, and methods
of structural stress analysis are to be researched in the future. A practical fatigue testing method is
also needed for investigating the strength in a high cycle region such as 108.