تحلیل عددی رفتار شمع های باله دار منفرد تحت بار جانبی در خاک های ماسه ای

زمانی‌که ظرفیت باربری خاک برای استفاده از پی های سطحی مناسب نباشد، معمولاً از شمع‌ها استفاده می گردد. شمع ها در اکثر موارد علاوه بر بارهای قائم، تحت بارهای جانبی نیز قرار می گیرند. شمع های مورداستفاده در پایه پل ها، توربین های بادی، سکو های دریایی و ... تحت بارهای جانبی بزرگی قرار می گیرند و در طراحی شمع های این سازه ها، بار جانبی غالب می باشد. استفاده از باله ها پیرامون شمع، جهت افزایش ظرفیت باربری جانبی روش نسبتا جدیدی می باشد، لذا در این تحقیق، رفتار شمع های باله دار منفرد در خاک ماسه ای به‌صورت سه‌بعدی با استفاده از نرم افزار اجزای محدود (abaqus) مورد بررسی قرارگرفته است. همچنین عملکرد شمع های باله دار با شمع‌های بدون باله مقایسه شده است. نتایج به‌دست‌آمده برای شمع های باله دار نشان می دهد که استفاده از باله ها منجر به افزایش چشمگیر ظرفیت باربری جانبی شمع ها نسبت به شمع های معمولی بدون باله می شود.

Numerical analysis of single finned pile under lateral loads in sandy soils

Piles are a common type of foundation, and in the context of offshore energy supply, they are used widely as foundations for wind farms or as anchors for floating facilities for oil and gas production. In both these applications, the pile response under lateral loading is critical, although the latter application is more capacity sensitive whereas the former is deformation sensitive. All piles are under small or large lateral loads and the behavior of the piles under the lateral load must be controlled, but for most of the time. The lateral load can cause a spacing between the pile and the surrounding soil in the upper layers. If such a situation happens, it cannot be assured for the vertical load bearing capacity in the upper layers. Usually, the effect of lateral loads on the design and construction of the pile is ignored due to its small size versus vertical load, but in some cases, the analysis of the pile is necessary under lateral loads and should be considered using the appropriate methods. The piles used in the base of bridges, wind turbines, piers, etc. are subjected to relatively large lateral loads, and in the pile design of these structures, the lateral effect is dominated. One of the ways to increase the lateral load bearing capacity is to use the technique of fin piles, which is a relatively new method. Fin piles are one type of piles that have four or more metal sheets that are welded at different angles to the pile environment. The behavior of fin piles is difficult to explain using simple pile -soil theories or two dimensional numerical analyses because of the complicated geometry of the piles. Due to the progress of numerical methods and the use of threedimensional software, numerical modeling of the pile and soil environment is possible more precisely. A fundamental study of soil response of piles subjected to static lateral loads in sand is conducted using the nonlinear finite element approach. The effects of pile properties, i.e., length and diameter, and the effect of fins i.e., fin length and fin width on the pile response of a pile subjected to lateral loads are also investigated. In this research, the behavior of singular fin piles under lateral loading in sandy soil is modeled using 3D finite element software (ABAQUS) The ABAQUS program is a robust engineering simulation program that, based on finite element method. Abaqus is capable of solving various problems from simple to complex nonlinear problems. With a large library of materials and elements, the program is capable of modeling materials such as metals, rubber, polymer, composites, concrete, soil and rock. In addition to solving structural problems, the ABAQUS program is able to solve complex heat transfer problems, thermalelectrical analysis, and soil mechanics problems. In this research, the performance of finned piles with respect to ordinary piles has been compared. The results show that the use of fins causes an appreciable increase in the bearing capacity of the piles compared to ordinary piles without fins.