الفهرس 
Objectives of the researchOnly 14 pages are availabe for public view
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Abstract
Passive pile loading is a form of lateral pile-soil interaction occurs when the movement of the soil past the piles is responsible for additional loads acting on the piles. One of the main examples of passive piles, piles supporting bridge abutments resting on soft clay subjected to a horizontal force induced by the lateral movement of the soft soil underneath recently constructed adjacent embankment.
An accurate representation of loading condition and pile-soil relative movement is needed for analysis of passive piles. Such design tool is not completely fulfilled in the existing analysis methods (conventional methods). Simulating this problem using three-dimensional finite element model taking into consideration the effect of applying different techniques in simulating the structural elements is examined herein. Verification of the numerical model is performed by back analyzing a published case study using centrifuge tests. A good agreement between the results of the numerical model and measurements of the case study is obtained suggesting that the current numerical model can be used for investigating the short-and long-term impact of soil lateral movement on piles’ performance. The effect of secondary consolidation settlement (Creep) on pile movement and straining actions is investigated and results has approved that creep in the studied case has a limited effect on performance of the passive piles.
Several analyses methods of passive piles were developed, but the international design specifications (AASHTO, British standards, Canadian foundation manual, etc.) did not recommend a certain method for passive piles analysis. Therefore, the validity/applicability of existing empirical and analytical conventional methods is examined by comparing their outputs with the validated finite element numerical model at various adjacent embankment load levels and construction time, soft clay thicknesses, and pile spacing to diameter ratios considering the dependence of the results on pile position (front or rear pile).
All the examined conventional methods examined underestimate the maximum moment and lateral displacement of passive piles compared to numerical models under the same conditions. Outputs of both applied conventional methods, and numerical model indicates that increasing the embankment load, thickness of soft clay layer, and pile spacing to diameter ratio results in an increase in the passive pile lateral movement and bending moment, unlike increasing the embankment construction time.
The main conclusion of the present study is that none of available conventional analyses can consider the complexity of the soil-structure-interaction of the real performance of passive loaded piles. All available conventional analyses can lead to under-designed piles. Hence, it is highly recommended applying a real three-dimensional finite element analyses with the most enhanced constitutive lows and the corresponding soil parameters to have a safe, durable, and economic solution.