This study investigates five cases of municipal solid waste (MSW) landfill slope failures in the USA, China, Sri Lanka, and Greece, with the aim of assessing the safety margins and reliability of these slopes. The stability and reliability of the landfill slopes were evaluated under both static and seismic loading conditions, using pre-failure geometries and geotechnical data, with analyses conducted in accordance with Eurocode 7, employing all three design approaches. Under static loading, the factors of safety were close to unity, and reliability indexes ranged from 1.0 to 2.8, both falling below the recommended values set by Eurocode. The landfill slopes failed to meet the stability criteria in Design Approaches 2 and 3, while in Design Approach 1, four out of five landfills met the criteria. Under seismic conditions, safety factors and reliability indexes were significantly lower than the prescribed criteria in all analyses. Sensitivity analyses revealed that in two cases, unit weight and friction angle were the dominant parameters, while cohesion was the dominant parameter in one case. The findings of this study underscore the importance of establishing minimum design requirements for MSW landfill slope stability to mitigate potential risks to public health and the environment.

A series of earthquakes that commenced on December 28, 2020, resulted in extensive material damage within a 50-60 km radius from the epicenter, located near the City of Petrinja. Due to the significant structural damage sustained by the building of Petrinja Primary School I, a decision was made to construct a new school building. The construction of the new school began in 2022 and was completed in 2023. This study presents the findings of geotechnical investigations conducted at the site of the new school, which included five static cone penetration tests (CPTu), two dynamic probing heavy tests (DPH), one Marchetti dilatometer test (DMT), and two profiles of multi-channel analysis of surface waves (MASW). The geotechnical investigations resulted in the development of a soil profile consisting of eight distinct zones. Recommendations for the foundation design of the new building have been provided, alongside an assessment of the risk of soil liquefaction. The potential for liquefaction has been identified within zone 4, which comprises clayey sands at depths ranging from 4 to 6 meters.