Due to congestion in overground space, many underground structures have been built to facilitate communications between cities. These structures constructions will induce soil displacement, cities planning rearrangement, and sometimes are near to future buildings constructions. In some cases, communication channels should be built to allow the underground junction between the building and the subway station. Numerical simulation has been carried out to study the tunnel displacement behavior during construction stages. Two different procedures of the communication channel construction were also investigated. The results reliability were evaluated by monitoring six points displacement in the sheet pile walls after completion of the foundation pit. The results obtained were reasonably close to the monitoring results proven reasonably of the research ideas and the method scientificity. The results showed using sheet piles walls, and struts before soil excavation could reduce considerably the lateral displacement of the subway line during the excavation process and induce augmentation in the subway line vertical displacement. The lateral displacement effect of the walls thickness variation is much superior to the one provides by the struts cross-section and pile's diameter variations.

A pile foundation is commonly adopted for transferring superstructure loads into the ground in weaker soil. They diminish the settlement of the infrastructure and augment the soil-bearing capacity. This paper emphases the pile-driving effect on an existing adjacent cylindrical and semi-tapered pile. Driving a three-dimensional pile into the ground is fruitfully accomplished by combining the arbitrary Lagrangian–Eulerian (ALE) adaptive mesh and element deletion methods without adopting any assumptions that would simplify the simulation. Axial forces, bending moment, and lateral displacement were studied in the neighboring already-installed pile. An investigation was made into some factors affecting the forces and bending moment, such as pile spacing and the shape of the already-installed pile (cylindrical, tapered, or semi-tapered). An important response was observed in the impact of the driven pile on the nearby existing one, the bending moment and axial forces were not negligible, and when the pile was loaded, it was recommended to consider the coupling effect. Moreover, the adjacent semi-tapered pile was subjected to less axial and lateral movement than the cylindrical one with the same length and volume for taper angles smaller than 1.0°, and vice versa for taper angles greater than 1.4°.

In this study, a three-dimensional (3D) response of anchored sheet pile walls was investigated on double-anchored sheet pile system during soils excavation and tunnel construction sequence. This construction procedure is executed in areas front and adjacent the sheet pile walls. This paper focused on both areas of construction effects on the sheet piles. This numerical study aimed at the evaluation of the variation of bottom wall bending moment, top wall lateral and vertical displacements and anchor reactions forces exerted in the sheet piles. This paper also described the variation of the total anchor's reactions forces from the upper and lower anchors rows. A parametric effect such as upper and lower anchors rows distance was also performed to evaluate the variation of the wall bending moment, displacement and anchors total forces. The analysis results indicated that the reactions forces developed in the lower anchor rods are always higher than those developed in the upper anchor rods. The higher the distance between the upper and the bottom anchors the lower the displacement of the top wall in any stage of the construction. The minimum bottom walls bending moment is developed in the case where the distance between the anchor's rows divided by the wall height is 0.51. Positioning the upper anchors at 0.15 and the lower at 0.39 the wall height from the top wall will induce minimum top wall vertical displacement during soil excavation. This paper presents the results and findings of the parametric study performed.

We performed 2D numerical simulations to study the dynamic heap formation of coarse particles in different dry and wet conditions. Our results show that the dynamics of the particles depend not only on the amount of liquid contained in the bulk, but also on the initial particles packing, i.e., the arrangement of the grains. The wet particles cohesion model effect on coarse discs heap formation is minimal. This effect is mostly noticed in the particle arrangement and the energy variation rather than the heap formation. We found that the energy of the system varies with the liquid content up to a threshold value, equal to 219% in our study, where the influences of the parameters are minimal. At high liquid volume, the final pile height and radius tend towards an asymptotic value. The initial particles arrangement has a significant impact on the behavior of the bulk after the opening of the lateral walls. The number of particles in the triangle, formed by the initial width of the packing as a base and with a depth equal to N × D, with N representing the number of particles on a vertical line and D their diameter, influences the final shape of the pile. Indeed, the larger the number, the smaller the height of the pile. The simulations performed with the same initial packing show that the cohesion and capillary forces reduce the bulk kinetic energy and increase the potential energy when used with the elastic-plastic spring dashpot model. For the directional constant model, the dependance of the torque on the normal force and the particle size explains that there is almost no difference between the dry and wet model regarding energies. Finally, the elastic-plastic spring-dashpot model is more efficient in reducing the kinetic energy of the system and producing stable piles. Our simulation results using glass beads are in good agreement with the experiments.

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