- 4289 - Evaluation of Effective Factors on the Load-Displacement Relationship of Laterally Loaded Single Vertical and Battered Piles Using FEM Analysis Reza Rezazade Department of Civil Engineering, University of Hormozgan, Iran e-mail: Reza.rezazade.69@gmail.com Behzad Kalantari Assistance Professor, Department of Civil Engineering, University of Hormozgan, Iran e-mail: Kalantari@hormozgan.ac.ir ABSTRACT Piles are used under structures such as tall buildings, bridges, tall chimneys and coastal structures which are usually subjected to large lateral loads such as wind load and earthquake. So, piles should be resistant against vertical and lateral movements. Battered piles provide enough resistance against lateral loads, hence they are used when the horizontal load on each pile appears to be going beyond the permitted level. In this research, effect of important factors in designing lateral loading capacity of piles as well as simultaneous application of vertical and horizontal loads have been studied to recognize the factors that influences the behavior of vertical and battered piles under lateral load. A series of model pile on sand was analyzed using the finite element method. Obtained results from this research indicate that; as the inclination angle of piles increase, lateral load bearing capacities of piles are increase as well. Also, Lateral load bearing capacities of negative battered piles are higher than positive battered piles and effects of diameter are more than the effect of length increase. As the imposed load’s angle on the pile increases to 90°, the load bearing capacity of the piles decreases too. KEYWORDS: Vertical single pile, Battered pile, Lateral load, Numerical method, FEM. I NTRODUCTI ON Generally, in areas where the loading capacity of the soil is low to a considerable depth, piles can be used to transfer vertical and lateral loads to the soil. Piles are used under structures such as tall buildings, bridges, tall chimneys and coastal structures which are usually subjected to large lateral loads such as wind load and earthquake. Imposed lateral loads to piles are caused by high winds, earthquakes, trucks of ships, ground pressure and etc (Ercan 2010). In general, piles should be resistant both to vertical and lateral movements. Piles are often used as a group, however, in some cases due to factors such as distances of piles from each other, their individual performance may be considered as single piles. Piles are divided in two categories, namely vertical and battered piles depending on their angle of installation. Usually, vertical piles are used to bear vertical loads and these piles have small lateral loading capacity. A