There are two common series of aluminum alloy that used to construct car body of light rail transit (LRT), i.e. Al 6061 and Al 6005a. Type of Al 6005a has lower strength but cheaper rather than Al 6061. In this numerical study, their extrusion characteristics based on strength consideration are analyzed using ANSYS Workbench 18. The 3D solid model is extracted from interior-exterior facet models of LRT. To save computational time, the car body model is simplified by removing fillets and then generating a symmetrical model. Anyhow, the effect of fillet removal is also studied by introducing a correction factor. Four cases of static loading are given to observe actual loading phenomena that could occur. The simulation results indicated that Al 6005a has better characteristics to be used for constructing the car body of LRT. In addition, simplifying the model in the FEM simulation of a rail-based car body using a shell element type and applying a correction factor to the simulation results is a breakthrough simulation method that could improve the accuracy of the results.

Flat wagons are logistic railway vehicles that are always subjected to a heavy dynamic load. One type is the 42 ton flat wagon developed by INKA Ltd., which is well known as PPCW flat wagon. The initial design of this flat wagon was operated using a container. Nevertheless, it can operate safely without a container as well. This study was conducted to mitigate the effect of fluctuating load on fatigue of 42 ton flat wagons as cement carriers, with or without a container. The 3D flat wagon model was built and exported to ANSYS Workbench 19 to simulate the effect of the variable and mean stresses generated within the wagon. Several operational modes were applied to the model, such as an accelerated condition of 0.21 m/s 2 , a constant straight track, a turn uphill track, an inclined track, a turn downward track, and a decelerated condition of 0.3 m/s 2 . Transient structural, static structural, and modal analysis types are applied in the simulation consecutively to adapt the track variations. Due to the loading being dominated by compressive load, a negative stress ratio of 1.5 was utilized as the stress ratio of alternating stresses. The numerical study indicated that the straight, turn uphill, and turn downward tracks could exaggerate the stress generated due to dynamic loading. Potential fatigue failure could occur because the dynamic load produced fluctuating stresses, either alternating or mean stresses, that could damage the structural integrity of the flat wagon.

In the design of critical components for railways, especially couplers, it is necessary to pay attention to the strength of the coupling between the couplers with each other. Coupling failure can have fatal consequences in the form of the train series being detached when operating. This study aims to improve the coupling strengthening of coupler prototype that meet international standard. The study begins with the calculation of longitudinal train force on light trains to obtain a coupler force followed by kinematics analysis on the initial coupler design to be improved using dimensional synthesis in the form of path generation and motion generation. Failsafe device design is done as an effort to strengthen the coupling. At the final stage, design verification is carried out in the form of structural strength analysis to compare the initial design with the new design. From the simulation results, it is found that the new design with a parallelogram configuration with 25° slope angle has a stronger coupling than the previous design. In addition, the addition of a failsafe device also plays a role in increasing the coupling strength of the coupler.

A new bogie frame of Light-Rail Transit (LRT) is having its strength of structure verified with experimental static testing according to EN 13749 standards. Static testing of bogie frame structure of LRT is performed by using a combination of seven tensile and compression loads that comprise of operational loads (normal service) and over-loads (exceptional service). Measurement parameters of bogie frame are strain and deflection values. The strain and deflection values resulted at every step of the load test were measured and monitored to further be used as analytic data. This data is then compared to the stress data of finite element analysis to check its deviation value. Testing results show the maximum stress value is 81.48 MPa on operational load, meanwhile, for exceptional load case, maximum stress is 120.96 MPa and deflection value is 1.25 mm. The maximum stress value is still below yield strength of bogie frame material S 555J2 (y=355 MPa). According to testing data, structure of bogie frame LRT fulfill as the acceptance criteria.

The bogie frame is the main structure of the train that supports the train's loads during its operation. These structures are subject to fatigue testing to ensure their design life is up to the required standards. The urban light rail transit (LRT) bogie frame used in the Greater Jakarta area is newly designed and manufactured by a commercial railway rolling stock manufacturer. The design lifetime of this newly designed bogie frame structure under various fatigue load conditions is verified experimentally by fatigue testing. Testing and evaluations were conducted following the EN 13749 standard and VDV recommendation. The fatigue test of the urban LRT bogie frame structure was carried out in the test hall of the BPPT Structural Strength Technology Center (B2TKS) using a combination of seven loadings. The bogie frame was subjected to two variable types of fatigue loads, namely driving in curves and passing points (switches), with 2,000,000 cycles, 4,000,000 cycles, and 6,000,000 cycles of fatigue loadings. The parameter measured on the bogie frame structure is the strain value during the test using a dynamic data logger. The stress values analyzed are the average stress and the stress amplitude and then plotted on the maximum and minimum stress curve. The bogie structure is inspected by the non-destructive test method in all areas of its welded joints. This inspection is carried out before and after the test to ensure whether there are cracks caused by fatigue loads. The results of the fatigue test on the bogie structure under the variable fatigue load conditions show that the maximum stress value of 91.71 MPa at 1,500,000 cycles, that occurs during the test, does not exceed the fatigue limit of the material, and there are no cracks in the structure after the test is carried out for up to 6,000,000 cycles.