Bedding parallel stepped rock slopes exist widely in nature and are used in slope engineering. They are characterized by complex topography and geological structure and are vulnerable to shattering under strong earthquakes. However, no previous studies have assessed the mechanisms underlying seismic failure in rock slopes. In this study, large-scale shaking table tests and numerical simulations were conducted to delineate the seismic failure mechanism in terms of acceleration, displacement, and earth pressure responses combined with shattering failure phenomena. The results reveal that acceleration response mutations usually occur within weak interlayers owing to their inferior performance, and these mutations may transform into potential sliding surfaces, thereby intensifying the nonlinear seismic response characteristics. Cumulative permanent displacements at the internal corners of the berms can induce quasi-rigid displacements at the external corners, leading to greater permanent displacements at the internal corners. Therefore, the internal corners are identified as the most susceptible parts of the slope. In addition, the concept of baseline offset was utilized to explain the mechanism of earth pressure responses, and the result indicates that residual earth pressures at the internal corners play a dominant role in causing deformation or shattering damage. Four evolutionary deformation phases characterize the processes of seismic responses and shattering failure of the bedding parallel stepped rock slope, i.e. the formation of tensile cracks at the internal corners of the berm, expansion of tensile cracks and bedding surface dislocation, development of vertical tensile cracks at the rear edge, and rock mass slipping leading to slope instability. Overall, this study provides a scientific basis for the seismic design of engineering slopes and offers valuable insights for further studies on preventing seismic disasters in bedding parallel stepped rock slopes. (c) 2025 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/ 4.0/).

The current study identifies the critical design considerations for the universal joint of a cutter suction dredger. The cutter suction dredger is modelled as a hybrid two subsystems consisting of hardware-in-the-loop (HIL) and Software-in-the-loop (SIL). HIL, consisting of Dredge hull, spud and soil embedment, is modelled experimentally. System identification is carried out, and a single degree of freedom (SDOF) system is determined for HIL. The identified dynamic parameters are interfaced with the SIL. SIL consisting of the cutter shaft is modelled numerically. The primary and secondary shaft of the cutter shaft is coupled using springs to emulate the universal joint. A sensitivity analysis of the acceleration amplification based on the spud location relative to the hull is carried out. It is observed that the spud position relative to the hull has less influence on the acceleration amplification. A soft universal joint produces a higher response transmitted to the Dredge hull. Further, the influence of the universal joint on the fatigue life of the shaft is analyzed. The results from the fatigue analysis indicate that higher coupling stiffness reduces the fatigue life of the cutter shaft. Therefore, while designing the universal joint, both the impulsive and the fatigue loading must be considered.