Experimental and Numerical Analysis of Laterally Loaded Single- and Double-Paddled H-Piles in Clay

Abstract

An efficient foundation system of single- or double-paddled H-piles (PHPs), which comprises steel H-piles fitted with specially configured steel plates (paddles), is proposed to support sound walls subjected to wind loading. The lateral responses of single-paddled (SPHPs) and double-paddled H-piles (DPHPs) installed in clay is evaluated using a comprehensive assessment of the foundation performance via a full-scale lateral load testing program, alongside extensive three-dimensional (3D) nonlinear finite element (FE) analysis. The comparison between the calculated and measured responses of the PHPs demonstrates that the developed numerical model accurately depicts the response of the PHPs under lateral load. The validated numerical model is then used to evaluate the effect of the soil consistency on the lateral response and capacity of the PHPs. The influence of the paddles’ configuration on the lateral response and capacity of the PHPs is also evaluated. Furthermore, the change in the PHP lateral stiffness due to adding a second paddle is also examined. Finally, the influence of the plates on the surrounding soil is investigated by analyzing the formation of the strain field around the pile and evaluating the extent of the soil influence zone at different plate-width-to-pile-flange-width ratios (Wp/Wf). The result of this study indicates that adding plates contributes significantly to the lateral capacity of PHPs in clay and reduces the maximum bending moment. The parametric study reveals that the top 5–6 Wp of the soil have a significant effect on the lateral response of the proposed H-pile. Based on the outcomes of the field tests and numerical analysis, optimal geometrical parameters for paddles are proposed.

Keywords

• paddled pile
• lateral loading
• clay
• model tests
• three-dimensional (3D) numerical analysis
• finite element