Résumé: In quarries and mines, the drilling and the blasting activities is an essentially fundamental way of excavating rock. The blasting process is an integral and important part of mining operations and is intrinsically destructive for a variety of different reasons, notably efficiency, cost effectiveness and the capacity to shatter away even the most solid rock. The primary and main purpose of designing a blast pattern in an open pit or quarry is to use quantities of explosives to fragment the rock material down to smaller pieces and shapes that can make it easier to carry out various subsequent operations such as excavation, charging, transporting, crushing, grinding etc. The conception of a blasting model depends on two sorts of variables: firstly uncontrollable factors, such as the geological structure and the properties of the rock mass. Secondly controllable factors, such as the geometric model (height of the bench, length of the charge, diameter, spacing, burden, stemming length, etc.), the properties of the explosives used (type, resistance, energy, etc.) and the temporal parameters (time delay and initiation sequences). The different fragmentation blasting analysis procedures have inherent difficulties, which result in varying levels of accuracy. Consequently, each technique is adapted to a particular purpose. This research assessed and then compared the particle size distribution of limestone rocks from the New Cement Quarry (NCQ) at Setif -NE Algeria, using the Wip Frag computer imagery processing program and one of the empirical models called Kuz-Ram. Three blasts from the quarry, using different mesh designs in terms of load and spacing (rectangular, square and triangular) analyzed using the two methods. The design parameters of the blast obtained and evaluated as input to the Kuz-Ram model. Pictures of the pile taken and downloaded to the Wip Frag software for analysis. The obtained results in the case of a change in the geometrical parameters of the explosion show that a significant reduction in the size of the oversized products observed by the numerical method. Furthermore, in this study, the ratio between the spacing and the charge in the case of the triangular pattern has a major influence on the size of the fragments and makes it possible to make optimum use of the distribution principle and the amount of energy of the explosive. Keywords: Rock fragmentation, blast pattern, kuz-ram, wip frag, particle size.

Résumé: The results of the numerical simulation correspond to the data of the maximum vertical displacement, which makes 4.18 ⋅ 10-3 m for the bed rock. This will allow obtaining possible decrease in tunnel outline, which makes properly 2.7 ⋅ 10-3 m with a floor heave of 0.75 ⋅ 10-3 m and the field of horizontal displacements of the order of 1.45 ⋅ 10-3 m. As a result of the research, the problem of mass displacement is solved with higher technical and economic efficiency. Keywords: tunnel, convergence-confinement, interaction, solid mass behaviour, support, Plaxis2D.

Résumé: Analysis of interactions between underground construction projects and both ground and surface structures is an increasingly strong issue in the geotechnical field, especially in urban areas during an ongoing underground construction project or an excavation project near existing buildings. Tunneling operations at a shallow depth in an urban site (e.g.: Algiers subway) induces, in extreme cases, ground movements that are capable of causing deformations and considerable damages to the nearby above ground structures. This work addresses the effect of the sequential excavation tunnel in by the Austrian method (NATM) at a shallow depth in an urban area, through a numerical model using Plaxis software (3D). The results of this model will be compared to those obtained by an In-Situ measurement comparing, in order to validate the numerical model and to make it easier to predict land deformations in an excavation zone. Tunneling by the Austrian method (NATM) at a shallow depth in an urban area, through a numerical model using Plaxis software (3D). The results of this model will be compared to those obtained by an In-Situ measurement comparing, in order to validate the numerical model and to make it easier to predict land deformations in an excavation zone. Keywords: Tunnel , Subway , NATM , Plaxis 3D , Sequential excavation.