Experimental Study on Flow Characteristics and Energy Reduction Around a Hybrid Dike

A high energy flow around a dike head is a dominant factor contributing to partial or complete failure of the dike. Due to the absence of sophisticated analyses, dike failure is not properly understood. For this purpose, a series of laboratory experiments were carried out to study the flow variations and energy dissipation around a single dike while changing the hybridity (H1:5 piles, H2: 10 piles, and H3: 15 piles). Changes in the flow structure around the dike were investigated to alleviate high energy swirls and dike head flow concerns. The proposed pile shapes were used in different pile configurations (H1, H2, and H3) to determine velocity variations, backwater rise, energy reduction rate, flow deflection angle, length and width at the dike tip, and discharge distribution percentage for different pile shapes: circular, delta vane, streamlined tapered, and angled plate footing. According to the findings, increasing the dike’s hybridity up to H3 had a reciprocal effect on depth-averaged velocity, backwater rise, energy reduction rate, and flow deflection while having a direct effect on the discharge distribution percentage. H1 with an angled plate footing hybrid dike provided the best results in terms of reduction in maximum energy (39%), tip velocity (35%), and depth-averaged velocity (75%) with the lowest increment (2%) of discharge dispersion in the dike field compared to an impermeable dike. The proposed solutions can reduce accelerated deterioration during floods and protect the dike head as well as the bank adjacent to the dike to prevent high energy flow failures.