Load-Settlement Behavior of Composite Caisson-Pile Foundation (CCPF) in Sand

Caissons and piles are commonly used foundation types for deep water bridges. Caisson is appropriate for long-span bridges, deep alluvial deposits, liquefiable soils, and significant vessel collisions, although they can occasionally become problematic because of difficulties in sinking and insufficient earthquake resilience. Because of its extensive length, decreased rigidity, limited vessel crash protection, and challenging construction requirements, pile foundations are not appropriate for deep sea. A composite caisson-pile foundation (CCPF), also known as a caisson and pile combination, can be used as a solution to the aforementioned issue. It is an innovative hybrid foundation that takes into account the benefits of both foundation kinds. The CCPF reduces construction costs and time while providing creative answers to difficult site conditions in deep water. This foundation structure is commonly used for river and sea crossing bridges. However, due to a lack of significant research on its geotechnical and structural properties, CCPF has not been extensively used. Reduced-scale model tests on instrumented CCPF in sand under static vertical loads were carried out based. The load-settlement responses of the foundation under static monotonic vertical loading are presented and discussed in this study.