This study focuses on the evaluation of the load transfer mechanism and the determination of the shape of the load distribution transmitted to the geosynthetic layer when a cavity appears under granular and cohesive backfills. Trapdoor experimental technique with high-speed acquisition of digital images and continuous monitoring of load and displacements were used for this purpose. Testing different soil types, it has been demonstrated that an approximate parabolic or inverted triangular load distribution seems acceptable for granular soil layer, whereas for cohesive backfill the load distribution could be approximately represented by two concentrated forces near the edges of the cavity. In both cases, an important overload on the soil surface could change the shape of the load acting on the geosynthetic sheet. Experimental results are then approached by Terzaghi’s formulation with an appropriate shape of load distribution and a convenient value of the earth pressure coefficient. Finally, recommendations are proposed to promote a better design of such reinforcement structures.

Today, most mines (coal, iron, and others) in Europe are already closed due to economic, environmental, and societal issues. Therefore, post-mining risk assessment and management remain crucial for mining authorities, policymakers, and planners. In the post-mining period, several hazards are likely to affect the surface areas in the closed mining sites. The impact of closed mines can lead to potentially damaging changes in surface and/or underground water flow, as well as the development of surface instabilities that can affect people or infrastructure, sometimes dangerously. The assessment of the different hazards must consider the interaction between the mining hazards and other risks (natural and technological). Thus, land use planning, particularly the rehabilitation of former mining sites, requires better tools to apprehend the multiplicity of hazards and their constraints. The paper presents a methodology considering the interactions between hazards around closed mines. After recalling the advantages of this multi-hazard analysis, the work consisted of, almost exhaustively, describing the three prominent families of hazards: mining, natural, and technological. Then, the possible interactions between hazards were described according to their nature (trigger or aggravating), their category (technical or regulatory), and their typology (dependent or independent). Finally, an attempt was proposed to evaluate the type and intensity of interactions between hazards. The multi-hazard assessment methodology was applied to a coal mine and showed the complexity and the utility of such a risk assessment analysis to improve risk management in closed mines.

This paper attempts to provide a decision support framework that can help risk managers in urban areas to improve their decision-making processes related to sustainable management. Currently, risk management strategies should no longer be selected based primarily on economic and technical insight. Managers must address the sustainability of risk management by assessing the impacts of their decisions on the sustainable development of a given territory. These assessments require tools that allow ex ante comparisons of the effectiveness and the likely economic, social and ecological impacts of the alternative management strategies. Therefore, this paper reports a methodological and operational framework, which aims to incorporate sustainability principles in a particular decision by taking all the dimensions that affect sustainability into account. This paper is divided into two main parts: one on the theoretical aspects of the proposed methodology and the other on its application to a flood risks management case in a municipality located in Meurthe-et-Moselle county (France). The results of the case study have shown how the methodology can be suitable for determining the most sustainable decision.

Theextraction of ore and minerals by underground mining may induce groundsubsidence phenomena. These phenomena produce several types of ground movement likehorizontal and vertical displacements, ground curvature and horizontal groundstrain at the surface, and associated building damage in urban regions. Theinfluence function is a well-known and efficient method for the prediction ofthese movements, but its application is restricted to mining configurationswith the same influence angle around the mine. However, this angle may displaydifferent values when the mine is not horizontal or when other subsidenceevents already occurred near the considered mine.In this paper a methodology and analgorithm are developed, based on the traditional influence function method inorder to take into account different influence angles. This methodology isimplemented in the Mathematicasoftware and a case study is presented with data from the Lorraine iron minefield in France. Ground movements calculated with the developed methodologyshow a fair concordance with observed data.