On 8 September 2023, Morocco was subjected to a significant seismic event. The earthquake occurred at 11:11 PM with a magnitude of Mw 6.8-7.2 in the province of Al Haouz. The epicenter of the earthquake was located at 30.9896 North; 8.4140 West, in the rural commune of Ighil, province of Al Haouz, Marrakech-Safi region. The Al Haouz earthquake had a significant impact on buildings, particularly in five provinces (Al Haouz, Chichaoua, Marrakech, Ouarzazate and Taroudant). The earthquake caused significant damage and loss of life in the affected regions, with a total of 69,674 buildings were damaged, 47,378 were partially destroyed, and 22,296 were totally destroyed. An analysis was conducted to assess the damage to reinforced concrete buildings in each of the two regions namely Al Haouz and Taroudant. The results indicated that the main causes of the observed damage were attributable to the nature of the soil, the short columns, soft story, the lack of sufficient reinforcement, and the construction materials used. An evaluation was conducted to assess compliance with Moroccan seismic regulations (RPS 2011) and identify deficiencies requiring revisions to the standard. This assessment also involved a comparison with other international seismic regulations, such as those in China and Eurocode 8, to examine best practices and learn valuable lessons. This comparative approach aims to enhance local standards by incorporating proven approaches to improving the seismic resistance of structures.

Landslides occurring at the interface of strata are among the most common forms of loess landslides in China. Statistics indicate that significant loess-red silty clay interface landslides induced by irrigation in the Heifangtai Platform than loess-paleosol interface landslides in the South Jingyang Platform. To uncover the permeability characteristics, structural failure patterns, and triggering processes of two typical strata structures. This study employs Nuclear Magnetic Resonance (NMR) and Scanning Electron Microscopy (SEM) techniques to investigate the permeability and structural failure of two soil combination types: loess-red silty clay and loess-paleosol. The results revealed a positive correlation between the stagnant water effect and flow rate, but a negative correlation with the initial water content. Notably, these two typical strata exhibited distinct differences in the stagnant water effect. In loess-red silty clay, continuous filling of mesopores and macropores by fine clay particles, while at the same time the agglomerates disintegration at the interface, thereby enhancing the stagnant water effect. In contrast, loess-paleosol exhibited good connectivity between the mosaic pores at the interface. This facilitated the formation of several elongated microcracks, which acted as dominant channels for infiltration and weakened the stagnant water effect. However, the macroscopic triggering mechanism for loess landslides in both loess-red silty clay and loess-paleosol combination strata remains similar. Irrigation water stagnates within the relatively impermeable layers, saturating and structurally damaging the bottom of loess layer, ultimately inducing landslides. These findings provide a scientific basis for the future study of loess landslide hazards in different strata structures, which is of great significance.