On 18 December 2023, a Ms 6.2 earthquake struck the Jishishan area in Northwest China, located at the border of the Qinghai-Tibet and Loess Plateau. The earthquake triggered shallow loess landslides, small rock failures, and soil cracks, mainly along hilly gullies and cut slopes at the edges of terraced fields. A rare large-scale flowslide also occurred in irrigated farmland. These seismic landslides and collapses blocked roads, buried farmland, damaged houses, and resulted in many casualties. Field investigations revealed that these geological hazards were concentrated around cultivated land. Consequently, cultivated land was introduced as an engineering geological zoning factor into the seismic geological hazard risk assessment for Jishishan area. The Newmark cumulative displacement model was refined by incorporating lithological uncertainties via the Monte Carlo method. Comparative analysis of coseismic geohazards with and without considering cultivated land suggests that, in loess-covered areas with cultivation activities, the consideration of the disturbed characteristics of soils provides a more accurate probabilistic risk assessment of seismic geohazards. Human cultivation and irrigation activities affect the physical properties of surface soil, the terraced fields around earthquake prone areas have a risk of earthquake-induced geological hazards. This study may offer valuable insights for hazard prevention and mitigation in high fortification intensity loess covered areas.

Long-span river or sea crossing bridge projects are commonly subjected to significant and complex long-term cyclic loads driven by factors such as wind and waves. The lattice-shaped diaphragm wall (LSDW) foundation, a novel and promising solution for long-span bridges, offers advantages in construction safety, adaptability, costeffectiveness, and stiffness. However, research in this area remains limited, impeding the further application of LSDWs. This study comprehensively investigates the bearing behavior of LSDWs under horizontal cyclic loads in soft soils. It introduces a detailed methodology utilizing a dual-layer wall setup and mathematical calculations to measure key parameters such as wall bending moments, displacements, and soil pressures. The research explores LSDW behavior throughout cyclic loading cycles, revealing trends in soil compression, densification, and displacement growth rates. Analysis of cumulative displacement and rotation patterns underscores the influence of load amplitudes and wall stiffness. The findings highlight the significant impact of cyclic loading cycles on cumulative displacement, with curve fitting revealing a logarithmic function with a strong correlation. Additionally, the study delves into the reduction in lateral soil resistance with increasing cyclic loads, proposing cyclic weakening factors for predicting soil pressure distribution and cyclic p-y curves. This study offers valuable insights into the comprehensive analysis and prediction of the performance of LSDW subjected to horizontal cyclic loading, with potential implications for long-span bridge construction projects.