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The conventional methods follow in designing piles adopt the assumption of saturated condition of soil depending on soil parameters at saturated condition while at most cases the whole piles or part of them lays in unsaturated soil zone, thus the estimated pile capacity will be far of the real. This issue made the need to study the pile capacity at unsaturated condition and compare it with saturated condition. This study is performed to investigate the behavior of single pile inserted in clay soil at different degrees of saturation. The test was performed under axial compression loads by using different degrees of saturation (100,80,60,40%). A pile of 14x14 mm cross section with different slenderness ratios (L/D) (24,30,36) employed in the study. The impact of saturation degree, matric suction and slenderness ratio on pile load capacity is examined. The results illustrate that pile capacity influenced considerably by the saturation degree, matric suction, and slenderness ratio. The results showed that when saturation degree reduced from 100% to (80,60,40%), bearing capacity of pile increased for all L/D used. An example ultimate capacity of pile with L/D (24) increased (380, 512, 63%) by de-creasing degree of saturation from 100 % to(80 ,60 ,40%) respectively, this means the pile capacity increased about four times by decreasing Sr. from 100 % to 80 % , five times by decrease Sr. from 100% to 60 % and little increase (63 %) in pile capacity by decreasing Sr. to 40 %.A close results had been observed at L/D 30 and 36. The effect of increasing slenderness ratio had been studied at different saturation degrees, an ex-ample by increasing L/D from 24 to 30 pile capacity increased (11.45, 10.2, 25, 32.5%) at Sr.(100 ,80 ,60 ,40%) respectively.

Earthquakes are sudden and unpredictable natural activity that causes severe damage. As a result of the increasing seismic activity in Iraq, it has become necessary to conduct a study on the impact of earthquakes and methods of damping them. Since traditional seismic damping methods for construction are very expensive, alternative solutions are necessary. Therefore, this research proposes a new damping method that depends on surrounding the piles with rubber crumbs, as the rubber works to dampen the seismic force before it reaches the piles before moving to the structure. This method is considered a type of sustainability. The study included a set of variables, including (the thickness of the rubber that surrounds the piles, and the position of placing the rubber that sleeved the piles). The tests were carried out using the shaking table device. The results showed that surrounding the piles with rubber gave distinct results in damping the seismic force and it is considered an easy damping method due to its ease of implementation, as well as its economic feasibility. The results showed for the models that surround the rubber in the upper part of the pile, an increase in the values of the acceleration of the structure and a decrease in the values of the movement speed of the structure, the values of the lateral displacement of the structure. The models in which the rubber surrounds the middle and bottom part of the pile, the results were close to the reference model.

A finite element method is practical and applicable for many fields including for geotechnical engineering structures. Seepage through earth dam is difficult to analyze especially dams with multiple zones. The problem becomes complex if it requires deformation analysis taking into account seismic conditions. Therefore, finite element is the best tool for analyzing seepage flow in an earth fill dam. The main objective of the paper is to simulate the seepage flow through an earth fill dam. Hassan Kanosh Dam which is located in the north eastern part of Iraq is chosen as a case study. There are three periods in the life of a dam which may be critical from the standpoint of shear failure and which must be analyzed; during construction condition, full reservoir condition, and rapid drawdown condition. The program SIGMA/W which is a finite element software coupled with SEEP/W, (another GEO-SLOPE software product) to analyze the dam. The stability analysis performed showed that all parts of the dam are safe within the prescribed rang of factors of safety for the possible loading and operation cases. It is recommended, however, that close control of the quality of the works during construction must be maintained to realize the shearing strengths necessary to fulfill the assumed strength and even more. It is recommended to check routinely the foundation conditions during excavation to realize the same end results.