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Commonly finite element analyses of embankments and excavations are conducted as two-dimensional representations of the true three-dimensional problem, but very little work was done in determining the relative applicability of these solutions until recently, when three-dimensional programs and high-speed computers became available. A trial embankment constructed in Vaasa (Finland) is analyzed in this paper. The main purpose of the construction was the testing and development of the design methods for the planning of road embankments. Settlements at the base level of the embankment were measured with settlement plates, and deeper in the ground with magnetic extensometer. The pore pressures were measured using open and closed piezometer tips installed at different depths. For the task of analysis carried out in this paper, a finite element computer program named (3-DFEP) was written. The program can solve three-dimensional coupled problems. Both the soil solids and the pore water are modeled by 8-noded brick elements. It was found that the results of three-dimensional analysis are more stable than do plane-strain ones. The settlement became approximately constant after about (600) days. The settlement predicted at that time was approximately (400) mm that is in good agreement with the recorded field data while plane-strain results showed continuous increase in settlement after that time.

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Abstract In the present work nonlinear finite element analysis has been used to predict the load displacement behavior of cellular retaining structure by using ANSYS (Analysis System) (version 9) computer program, eight-node brick element has been used to model cellular cofferdam and soil, non linear material behavior is adopted for the soil in which a Drucker - Prager (DP) model is used to represent that nonlinearity The bond between cellular cofferdam and soil has been modeled by using surface to surface contact element , using of models in ansys program have been carried out on one (single) circular cell of width to height ratio equal to (1.00), with embedment depth ratios equal to (0.2H, 0.3H, 0.4H ) , and use three type of soils, these types subbase ,sand passing sieve No.4 and river sand . and their results are compared with experimental data[Al-Khyatt, (2009)] and found to give good agreement.

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Abstract. Piles can be damaged due to the lateral soil movement induced by constructing a nearby embankment. These movements introduce lateral loads “passive loads” on the piles which in turn increase the lateral forces and bending moments within the piles. In some cases, these induced forces and moments may exceed the pile capacity and cause failure. This research investigates experimentally the effects of soil movement on the behavior of nearby axially loaded and unloaded rigid pile groups driven in sandy soil having a dry unit weight of 13.5 kN/m3. The model piles are made of aluminum and have an embedded length (Le) of 360 mm, free head of 140 mm, and diameter (D) of 10 mm. The embankment loads are applied at distances of 2.5D, 5D, and 10D from the edge of the pile group. The obtained results showed that the presence of axial loads decreases the displacement at the soil surface. It was found that the axially unloaded pile group (UG) had displaced more than the axially loaded pile group (LG) by 16, 25, and 35% at 2.5D, 5D, and 10D respectively. Moreover, increasing the distance between the embankment and the edge of the pile group had significantly decreased the maximum soil reaction due to the reduction of soil movement pressure.

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Abstract: Based on the results of standard penetration tests (SPTs) conducted in Al-Basrah governorate, this research aims to present thematicmaps and equations for estimating the bearing capacity of driven piles having several lengths. The work includes drilling 135 boreholes to a depth of 10 m below the existing ground level and three standard penetration tests (SPT) at depths of 1.5, 6, and 9.5mwere conducted in each borehole. MATLAB software and corrected SPT values were used to determine the bearing capacity of driven piles in Al-Basrah. Several-order interpolation polynomials are suggested to estimate the bearing capacity of driven piles, but the first-order polynomial is considered the most straightforward. Furthermore, the root means squared error (RMSE) for all suggested polynomials are roughly the same. The production of thematic maps demonstrates the variation in bearing capacity of driven piles over the entire territory of Al-Basrah governorate in correlation with different depths. The results of the statistical equations showed that there is good agreement with those obtained from the SPT data. When compared with the observed values from SPT, the allowable bearing capacity results for the driven piles ranged from (−3 to +38)%. The main results of this study showed a variation of 30% between calculated and estimated values of bearing capacity of driven piles for all lengths of piles at a 95% confidence interval.

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