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Studies of craters produced by explosions above and underneath the ground surface are rarely found in the open technical literature. Most reports are confidential and access is limited to government agencies. Much of the information on explosively formed craters found in the literature is based on experimental data. Numerical studies were very limited until recently. An ablity to predict the anticipated size of crater is crucial to identification of the corresponding damage that might be caused by a given explosive charge, or to assessment of the magnitude of the charge if this is not known. In this paper a non-linear dynamic numerical analysis of the explosion phenomena in clay soils associated with different amounts of TNT explosive charge is performed using the ABAQUS/Explicit computer program. To validate the numerical procedure and material constitutive models used in the present work, a comparison with experimental results is first performed. The results obtained illustrate that the agreement between the numerical and the experimental results is reasonable. A study of the influence of soil density on the crater dimensions is then undertaken. From the numerical results obtained, a new prediction equation is proposed for the crater dimensions as a function of the explosive charge considered. This equation represents the approximation of the numerical results by least squares fitting.

The response of buried concrete structures to the effect of blast loads is of great importance. Various parameters including the depth and weight of explosive charge, soil properties and the relative location of the buried structure to the explosive charge affect the structural performance of buried structures. In this paper, the influence of burial depth of explosive charge is numerically investigated using the new proposed finite element model developed and described in a previous work for the authors. The burial depth of explosive charge is considered to be varied between 0.0 m to 6.0 m. A comparison evaluation is carried out between the study of varying charge depth and the study of varying the burial depth of the structure. This investigation covers the blast wave propagation, structure response and damage analysis for buried reinforced concrete structures. The paper shows that buried explosions result in significant effects on the structure response than the surface explosions with the same conditions.

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Solid waste management is a serious problem worldwide as the amounts of produced wastes are increasing annually. For example, the disposal of waste gypsum plasterboard, used as dry walling across the world, represents a serious environmental issue. Therefore, this study examines the potential for reusing plasterboard wastes as a stabiliser material for earthwork projects, especially for organic soft clay soil. Recycled plaster, mixed with cement or lime at different ratios was used as a stabiliser for tested soil. Atterberg limits, scanning electron microscopy, x-ray diffraction, compressive strength, and secant moduli tests were conducted to evaluate the improvement in stabilised soil properties. The results indicate that the inclusion of plaster–cement (B–C) or plaster–lime (B–L) admixtures improved the geomechanical properties of the stabilised soil, with higher admixture concentrations leading to greater improvement. Moreover, the soil specimens stabilised using the B–L admixture exhibited a higher strength gain rate and reduction in plasticity index and water content than those stabilised by the B–C admixture. The development of cementation compounds in a stabilised soil matrix has a considerable effect on permanent strength enhancement. It is concluded that the proposed stabilising technique can be valuable for both waste management and construction industries.