M. Hallaj
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Centrifuge Modelling of Dutch Railway Embankments on Soft Clays
The RESET Experimental Program
Conference paper
(2026)
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Cihan Cengiz, Cor Zwanenburg, Timo Schweckendiek, Alexander van Duinen, Mark Post, Agnes van Uitert, Stefano Muraro, Maryam Hallaj, Cristina Jommi
In the Netherlands, railway embankments founded on soft clay are sensitive to progressive deformation and pore pressure development under increasing traffic demands. Within the Rail Embankment for Safe Expansion of Traffic (RESET) research programme, a centrifuge test series was conducted to generate a controlled experimental dataset describing embankment behaviour at failure conditions. Eight centrifuge tests were performed at 50g using a 1:50 scaling ratio. The testing -programme included systematic variation of clay undrained shear strength, embankment geometry, ditch presence, and loading rate. The clay foundation consisted of consolidated kaolin, and the embankment was constructed of dense sand. Loading was applied under displacement control using a rigid plate with rotational freedom to allow realistic load redistribution. The instrumentation programme combined global load–displacement measurements, total and pore water pressure monitoring, in-flight T-bar strength profiling, particle image velocimetry (PIV) for full-field deformation analysis, and post-test 3D surface scanning. The present contribution elaborates on the experimental configuration and principal observed response patterns, providing a benchmark dataset for future modelling and assessment studies.
The RESET centrifuge programme comprises eight heavily instrumented tests defining a controlled experimental parameter space. As illustrated in Figure 1, the testing programme matrix is structured along three principal axes. The primary axis governs foundation stiffness contrast, achieved through systematic variation of the clay undrained shear strength, which enables isolation of the influence of subsoil stiffness on peak resistance, strain localisation, and post-peak kinematic evolution. The second axis investigates loading rate under displacement-controlled conditions, which permits examination of shear-rate effects on pore pressure generation and strain development. The third axis isolates the geometric boundary condition associated with the presence of a ditch, which alters lateral confinement and thereby affects the formation and extent of the failure wedge. These axes establish a mechanism-oriented framework within which the transition from punching-dominated response to progressive wedge development can be examined. ...
The RESET centrifuge programme comprises eight heavily instrumented tests defining a controlled experimental parameter space. As illustrated in Figure 1, the testing programme matrix is structured along three principal axes. The primary axis governs foundation stiffness contrast, achieved through systematic variation of the clay undrained shear strength, which enables isolation of the influence of subsoil stiffness on peak resistance, strain localisation, and post-peak kinematic evolution. The second axis investigates loading rate under displacement-controlled conditions, which permits examination of shear-rate effects on pore pressure generation and strain development. The third axis isolates the geometric boundary condition associated with the presence of a ditch, which alters lateral confinement and thereby affects the formation and extent of the failure wedge. These axes establish a mechanism-oriented framework within which the transition from punching-dominated response to progressive wedge development can be examined. ...
In the Netherlands, railway embankments founded on soft clay are sensitive to progressive deformation and pore pressure development under increasing traffic demands. Within the Rail Embankment for Safe Expansion of Traffic (RESET) research programme, a centrifuge test series was conducted to generate a controlled experimental dataset describing embankment behaviour at failure conditions. Eight centrifuge tests were performed at 50g using a 1:50 scaling ratio. The testing -programme included systematic variation of clay undrained shear strength, embankment geometry, ditch presence, and loading rate. The clay foundation consisted of consolidated kaolin, and the embankment was constructed of dense sand. Loading was applied under displacement control using a rigid plate with rotational freedom to allow realistic load redistribution. The instrumentation programme combined global load–displacement measurements, total and pore water pressure monitoring, in-flight T-bar strength profiling, particle image velocimetry (PIV) for full-field deformation analysis, and post-test 3D surface scanning. The present contribution elaborates on the experimental configuration and principal observed response patterns, providing a benchmark dataset for future modelling and assessment studies.
The RESET centrifuge programme comprises eight heavily instrumented tests defining a controlled experimental parameter space. As illustrated in Figure 1, the testing programme matrix is structured along three principal axes. The primary axis governs foundation stiffness contrast, achieved through systematic variation of the clay undrained shear strength, which enables isolation of the influence of subsoil stiffness on peak resistance, strain localisation, and post-peak kinematic evolution. The second axis investigates loading rate under displacement-controlled conditions, which permits examination of shear-rate effects on pore pressure generation and strain development. The third axis isolates the geometric boundary condition associated with the presence of a ditch, which alters lateral confinement and thereby affects the formation and extent of the failure wedge. These axes establish a mechanism-oriented framework within which the transition from punching-dominated response to progressive wedge development can be examined.
The RESET centrifuge programme comprises eight heavily instrumented tests defining a controlled experimental parameter space. As illustrated in Figure 1, the testing programme matrix is structured along three principal axes. The primary axis governs foundation stiffness contrast, achieved through systematic variation of the clay undrained shear strength, which enables isolation of the influence of subsoil stiffness on peak resistance, strain localisation, and post-peak kinematic evolution. The second axis investigates loading rate under displacement-controlled conditions, which permits examination of shear-rate effects on pore pressure generation and strain development. The third axis isolates the geometric boundary condition associated with the presence of a ditch, which alters lateral confinement and thereby affects the formation and extent of the failure wedge. These axes establish a mechanism-oriented framework within which the transition from punching-dominated response to progressive wedge development can be examined.
The railway track superstructure including rails, sleepers and ballast is the primary interface between the train induced dynamic loads and the underlying embankment and subsoil, and plays a crucial role in load transfer, energy dissipation, and vibration attenuation. Accurate assessment of the train induced dynamic response of soft soils requires prior characterisation of the load transferred by the track superstructure. Hammer impact testing is an effective method for evaluating track dynamics, as it excites a broad frequency range and enables identification of the system natural frequencies through resonance amplification in the measured response. This study analyses the dynamic response of a laboratory railway track model consisting of rails, sleepers, and ballast subjected to hammer impact excitation as an aid to the development of a reliable finite element (FE) model of railways on soft soils. A three-dimensional finite element model of the experimental setup is developed in LS-DYNA to simulate the transient dynamic response of the track system. The numerical results are compared with the vibration time history and the frequency response function measured experimentally on the ballast layer. The finite element model is used to perform a sensitivity analysis to evaluate the influence of relevant input parameters of the track on the dynamic response measured on the ballast layer. The results suggest that different track components govern distinct frequency ranges of the system response, enabling efficient modelling strategies for railway systems on soft soils.
...
The railway track superstructure including rails, sleepers and ballast is the primary interface between the train induced dynamic loads and the underlying embankment and subsoil, and plays a crucial role in load transfer, energy dissipation, and vibration attenuation. Accurate assessment of the train induced dynamic response of soft soils requires prior characterisation of the load transferred by the track superstructure. Hammer impact testing is an effective method for evaluating track dynamics, as it excites a broad frequency range and enables identification of the system natural frequencies through resonance amplification in the measured response. This study analyses the dynamic response of a laboratory railway track model consisting of rails, sleepers, and ballast subjected to hammer impact excitation as an aid to the development of a reliable finite element (FE) model of railways on soft soils. A three-dimensional finite element model of the experimental setup is developed in LS-DYNA to simulate the transient dynamic response of the track system. The numerical results are compared with the vibration time history and the frequency response function measured experimentally on the ballast layer. The finite element model is used to perform a sensitivity analysis to evaluate the influence of relevant input parameters of the track on the dynamic response measured on the ballast layer. The results suggest that different track components govern distinct frequency ranges of the system response, enabling efficient modelling strategies for railway systems on soft soils.