Investigation of group behavior of pile foundations

In this master's thesis, the bearing behavior of pile foundations especially grour piles preferred n regions with insufficient soil bearing capacity, is examined in detail The study numerically analyzes the effects of parameters such as spacing between piles. pile diameter, pile material, and pile arrangement on the bearing capacity of group pile foundations. Based on the theoretical approaches proposed by researchers such as Terzaghi, Meyerhof, and Hansen, calculations for end bearing and shaft friction were carried out.In the efficiency analyses, the 1/8 Rule and the Converse-Labarre Rule were taken into account. The numerical part of the study was conducted using MATLAB codes for different soil types (clay and sand). With the aid of these codes, the bearing capacities of both single and group piles under various soil conditions and pile geometries were compared. The findings indicate that an increase in pile diameter results in a nonlinear increase in bearing capacity, that end bearing resistance is higher in undrained clay soils, and that in sandy soils, the bearing capacity calculated using the Terzaghi approach is higher than that calculated using the Meyerhof method. Furthermore, it was determined that as the spacing between piles increases, the interaction within the group decreases and the piles tend to behave more independently. The results obtained provide significant design recommendations that can be utilized in safe and economical pile foundation designs.In this study, lateral loads, stratified soil conditions, soil settlements, and minimum and maximum pile diameter limits were disregarded. The ultimate objective of the study is to determine which bearing capacity calculation methods and which combinations of theoretical approaches yield safer or more economical designs for specific soil types. Keywords: Group pile foundations, Group pile efficiency, Group pile analysis using MATLAB, Terzaghi, Meyerhof, Bearing capacity of single and group piles.