Ground reinforced embankment (GRE) is a common and efficient rockfall mitigation measure. However, due to the diversity of geometric dimensions and composite components of the embankments worldwide, the design methods have not yet been unified. This article proposes a DEM-based framework for modeling the GREs impacted by rockfalls, and to optimize the structural design by comparing the block-intercepting performance. The numerical model based on MatDEM is validated by restoring the Peila's field tests, and the simulated materials are calibrated by comparing the laboratory test results. The design elements can be determined through simulated impact tests, with the site topography and rockfall trajectory as prerequisite information. The simulation test results show that the structural positions and cross-sectional shapes alter the interaction between rockfalls and embankments, thereby affecting the block-intercepting capacity. Under the impact of high-energy blocks, the characteristic of structural failure is that the extrusion of the downhill face is greater than the displacement of the uphill face, which can be used as a criteria to determine the reasonable design elements. The proposed framework can be applied to an actual site and maximize the cost-benefit performance of design depending on the site space and budget conditions.

The soils in the eastern region of Qinghai, China, are characterized by typical unsaturated loess with poor engineering properties, rendering them susceptible to geological disasters such as landslides. To investigate the mechanical properties of these soils, triaxial and direct shear tests were conducted, followed by simulations of deformation and stability under freeze-thaw cycles using the discrete element software MatDEM, based on the experimental data. The findings indicate that (1) the stress-strain curves from both tests typically exhibit weak strain-softening behavior, with increased matric suction enhancing shear strength; (2) in the direct shear test, both cohesion (c) and the angle of internal friction (phi) rise with matric suction, whereas in the triaxial test, cohesion increases while phi decreases; and (3) an increase in freeze-thaw cycles results in a gradual decline in slope safety factor, though the rate of decline diminishes over time. Additionally, initial water content and slope gradient changes significantly affect slope stability. These insights are essential for geohazard risk assessment and the formulation of prevention and control strategies in Qinghai and similar alpine regions.

隧道长期运营情况下，由于自身地质条件及日常养护不足等经常导致出现多种病害问题。国家高速公路网荣成至乌海高速公路抢风岭隧道ZK77+265—ZK77+313至K77+213—K77+357段，其地基层以泥岩为主，由于泥岩具有较强的亲水性，隧道在部分仰拱区域产生冻胀、融沉和吸水膨胀3方面病害。基于离散元软件MatDEM对其进行建模，并模拟隧道冻胀融沉和吸水变形的过程。根据试验所得的体变率-吸水率关系，以颗粒粒径增大/缩小的方式来改变颗粒体积，进而完成吸水膨胀、岩体冻胀和融沉过程的模拟。结果表明当地下水位处于4 m以上位置时都能促使隧道破坏，而只有地下水位低于4 m时，对隧道结构的影响较小。

隧道长期运营情况下，由于自身地质条件及日常养护不足等经常导致出现多种病害问题。国家高速公路网荣成至乌海高速公路抢风岭隧道ZK77+265—ZK77+313至K77+213—K77+357段，其地基层以泥岩为主，由于泥岩具有较强的亲水性，隧道在部分仰拱区域产生冻胀、融沉和吸水膨胀3方面病害。基于离散元软件MatDEM对其进行建模，并模拟隧道冻胀融沉和吸水变形的过程。根据试验所得的体变率-吸水率关系，以颗粒粒径增大/缩小的方式来改变颗粒体积，进而完成吸水膨胀、岩体冻胀和融沉过程的模拟。结果表明当地下水位处于4 m以上位置时都能促使隧道破坏，而只有地下水位低于4 m时，对隧道结构的影响较小。

Ground reinforced embankment (GRE) is an economical and efficient protection measure against rockfalls. In various design guidelines of ground reinforced embankments, the impact force of the rockfall is the principal factor, which is significantly affected by rockfall shape. This article conducts real scale tests and numerical tests to observe the external deformation behavior and the internal dynamic response of GREs subjected to lateral impact. Five shapes of the rockfalls corresponding to three contact types are set up in the tests. The experimental results show that the impact surface shapes of the rockfalls govern the penetration deformation patterns of the embankments, and the deformation extent of the disturbed soils. For different contact types between rockfalls and construction materials, the failure mode of the geosynthetics and the displacement distribution of the disturbed soils are distinguishing. The disturbed soils can be divided into two parts, the part surrounds the rockfall mainly expands laterally, and the rest is extruded and slips backward. Basically, the sharpness of the rockfall results in the deeper penetration and the smaller impact force. The influence of the rockfall shape needs to be carefully considered in the design of ground reinforced embankments.