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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 calculation 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 are 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) is 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 becomes approximately constant after about (600) days. The settlement predicted at that time is approximately (400) mm which is exactly recorded in the field while plane-strain results showed continuous increase in settlement after that time.

Now, using of geogrids as strengthening material are extend used, especially to enhancement of concrete elements as inter layers concrete applications, eight beams were tested to explain the effect of geogrid on the behavior of reinforced concrete beams. Beams tested had equal cross-sectional dimension (100 mm x 200 mm), compressive strength (f’c = 30 MPa), with a simply span length equals 1150 mm, with shear reinforcement (Ф4 @100mm C/C) and subjected to two point load. The tested beams were divided into two groups according to the presence of geogrid layer, with and without geogrid. Each group consists of four specimens, which were sub-divided according to the flexural reinforcement ratio that ranges from (0 to 0.0263). During the tests, it was noted that, the load deflection curve for beams with geogrid layer were stiffer and the percentage of stiffening was increased with increase of the flexural reinforcement ratio. The maximum applied load for beams with geogrid layer were higher than conventional beams without geogrid layer under the same conditions, while, the deflection values for beams with geogrid layer was lower than conventional beams without geogrid layer. The first crack load of beams with geogrid was greater than conventional beams without geogrid layer. So, the geogrids layer offer great enhancements to concrete properties and performance from the first cracking load, load-deflection response, reduce the cracks width and number and ultimate strength of tested in comparison to the conventional beams.

The study examined the effect of bearing capacity of soil on the relative compaction by taking samples from different sites and carrying out strength experiments and comparing bearing capacity with the relative compaction to investigate the possibility of reducing the percentage of the approved measurements in the specifications of the percentages allowed for buildings with fixed load. A number of parameters have been prepared to calculate the amount of the degree of measurement to be adopted and the light tolerance required in any engineering work and for various factor of safety and non-compliance with specifications, which require in most cases to be the degree of compaction more than 95%. Linear regression equation between bearing capacity and relative compaction was proposed that can be applied without complying with required specification.