Pile groups mostly are used for translating the load of structures to soil and a pile cap is used on the top of the group. Lateral loading in designing pile group is important. In pile group under lateral loading, each pile is influenced by neighboring piles. The spacing between piles has an important effect on lateral bearing capacity.

In this paper behavior of long pile under lateral loading using PIV (Particle Image Velocimetry) method, in laboratory, was studied. In these tests the effects of inclination and stiffness of piles, were studied. The soil was made of loose poorly and fine sand (SP). The total length of pile was 40 centimeters and the embedded length of long pile was 37cm. For long pile, the inclined angles were: q=±5o, q=±10o and q=±15o. If the pile is under compression, it is considered positive, otherwise it is negative. After doing tests and analysis of the piles results, it was observed that the bearing capacity of batter pile is more than vertical pile, and the bearing capacity of negative batter pile is more than positive batter pile too. The piles results are observed that the effect of the inclined angle of the pile is more considerable than being positive or negative. For example the bearing capacity of+10o pile is more than -5o pile. It was observed also if inclined angle of the pile increases, the rigid length of pile will reduce, and for negative piles, this length reduces too. In batter pile, under lateral loading, the pile is taken under axial force, consequently cause more settlement.

Nowadays, using the pile group has special importance due to the transfer of structure load to hard layers of soil or rock. Therefore, any damage to the pile group can lead to irreparable risks. On the other hand, the importance of explosive loading and the development of passive defence systems require more appropriate measures concerning the effects of explosion loading on the pile groups. One of the most important parameters in pile group is pile space. In this study, the effects of pile space in the pile group under explosion loading are investigated. For this purpose, the numerical analysis of the pile group has been performed using the Abaqus software and by Coupling Eulerian-Lagrange method. According to the results, it was found that increasing the lateral or longitudinal pile space in the pile group would improve the condition of the pile group against the explosive loading.

One of the important lateral forces is dynamic loading due to earthquake. The behavior of pile foundations under earthquake loading is an important issue that widely affects the performance of structures. The topic of seismic pile behavior has been covered extensively in the literature over the past few decades. In this paper the behavior of single pile and pile group have been examined. Pile group has four piles and rebar and concrete weight in pile group is equal to single pile in this research. The single pile and pile group are analyzed under Tabas, Bam and Loma-perita earthquakes loading. The finite element software, ABAQUS, is utilized to model pile and piles group. Soil is modeled as an elastic-perfectly plastic model using the Mohr–, Coulomb constitutive model. The side boundaries are constrained against horizontal direction and the bottom boundaries are constrained against both horizontal and vertical directions. Maximum shear force, lateral displacement and force along the pile in single pile and pile group, under the earthquake loading that mentioned above, have been measured. The results are shown the settlement in pile group is around 30 percent less than single pile and the lateral displacement in the head of single pile is 0. 23 meter but the lateral displacement in group pile is 0. 1 meter in Bam earthquake loading. The shear force in the head of single pile is 2084 kN and the shear force in head of the pile in pile group is 334 KN. Taking into account soil condition, the results shown that utilize the pile group (equal rebar and concrete weight by single pile) is better and more economic than single pile.

The behavior of soil-pile systems subjected to earthquake loading depends on many parameters. These parameters can be categorized into three main groups: geometrical parameters of the pile, soil mechanical properties, and loading characteristics. The purpose of this study is to investigate the effect of pile geometrical parameters on the seismic response of soil-pile systems considering soil nonlinear behavior. To this aim, a set of fully nonlinear three-dimensional analyses in the time domain was conducted using the finite difference computer program FLAC3D. The focus of the paper is on the seismic response of the floating single pile embedded in clayey soil and the parametric study was performed to investigate the effect of pile geometrical parameters on its seismic response. To consider soil nonlinear behavior during seismic events, an elastoplastic constitutive law was applied to the soil medium. Also, soil shear modulus reduction with the increase in soil shear strain level was simulated. The results of this study showed that an increase in pile diameter causes an increase in the maximum kinematic bending moment. This increase is proportional to the pile diameter powered by a value. Also, the results showed that effect of pile length on the magnitude of maximum bending moment in pile was not significant. However, the shape of the bending moment distribution diagram and location of the maximum bending moment are strongly affected by pile length.

The computer program CA2 (Continuum Analysis, 2-dimensional), which can solve two-dimensional large strain plasticity problems, is used to model pile driving. The strength of the soil is characterized by a Mohr-Coulomb elastic-perfectly plastic model, and a distinct element approach is used to model pile-hammer interaction. Several numerical tests are performed to demonstrate the importance of different parameters involved in pile driving.

A study of various deficiencies observed in the process of pile carpet weaving in the Province of Kashan has revealed that the most important defects are: unevenness, crimpled sides and erroneous application of the cartoon. Improving weavers' skills will have a significant effect on reducing these defects.Therefore, weavers should be given educational advice on recognizing the capabilities of looms and other rug weaving equipment, the quality of raw materials and their harmonious use, the correct way of weaving flatwoven rugs, the manner of interlacing the wefts, and daftin-zadan (pounding an iron comb on the weft).