Search results

The vehicle–track interaction and the resulting dynamic response of the vehicle involve a number of complex nonlinear problems. Large vertical loads act through a small contact patch leading to very high contact pressures. Transverse loads acting through this contact induce a relative velocity between wheel and rail expressed in non-dimensional form as a creepage. The wheel and rail profiles determine the contact patch shape and affect the ability of the vehicle to run stably. If the yaw stiffness of the axles is too low, the vehicle will become unstable at a relatively low speed; conversely, if the yaw stiffness is too high, the curving behaviour will be adversely affected. The vehicle suspension, especially the secondary suspension, also affects the ride comfort of passengers. Finally, it is shown how the speed profiles of accelerating and decelerating trains can be calculated from basic assumptions about the train power, adhesion and rolling resistance.

Khiva is a UNESCO World Heritage site with ancient mudbrick buildings and a complete city wall. These are threatened from below by water and salt, and we seek to understand how the deterioration is happening and can be stopped. We have done investigations in the subsoil over several years to determine that destruction is caused by waterlogging, shifts in the ground, termites, and other damage. The damage has been caused by agricultural practices, especially leaky irrigation systems. Some of Khiva's buildings are becoming structurally unsound from water damage. Our studies at several sites confirm that water diversion will be necessary to prevent further infiltration of salt and water. Khiva's legacy is contained in the ancient buildings which are an important part of Silk Road history. Our research contributes to the understanding how to protect mudbrick buildings from environmental factors and deformation processes.

This chapter describes the approach to sustainable rail passenger rolling stock in terms of interior passive safety requirements within the European market. It is intended to give the background and logistical approach for the future introduction of a standard as an aid for the design and validation of the interiors of passenger rail vehicles. Also discussed is the acceptance of the proposed European-based standard into the regulatory system of the technical specifications for interoperability. Methodologies for design assessment and validation will be discussed. This chapter is intended to encourage an acceptance of the standard for interior passive safety as a realistic and cost-effective method of improving rail vehicle safety in terms of the passenger interfaces with the rail stock interior.

The evolution in developed countries has taken a role in global warming and natural disasters such as flash flood, El-Nino, earthquake and groundwater contamination. The underground storage tank leakage problems and spillage of hydrocarbon liquid leading to the contamination of non-aqueous phase liquids (NAPLs) into the groundwater could reduce the quality of groundwater. This chapter is intended to investigate the behaviour and the pattern of NAPL migrations in double-porosity soil under vibration and intact conditions. The experimental model is developed by using kaolin soil type S300 and toluene as NAPLs. The kaolin soil was mixed with 25% of moisture content to produce kaolin granules in the soil column and vibrate under 0.98 Hz of frequency within 60 seconds. As a result, both specimen liquids completely migrated to the bottom of soil column: sample 1 has higher permeability compared to sample 2. This is due to the fracture in double-porosity soil under vibration effect and loosened the soil structure in sample 1 compared to good intact soil sample 2 with stronger and compact soil structure. In conclusion, this study proves that the dangerous hydrocarbon NAPL migration in fractured double-porosity soil has very harmful effect on the environment and groundwater resources.