Development of spread foundation composed of micropiles and soilbags to reduce seismic response of structures

The authors have developed a new type of foundation composed of micropiles and soilbags. The foundations are characterized by the laying of soilbags on pile heads and the construction of structures such as piers and rigid frame viaducts on the soilbags. The expected benefits are elimination of the need for pile-footing connections, a smaller diameter of piles, and a reduction in the response acceleration of structures. In this study, in order to clarify the characteristics of the seismic response of the developed structure, shaking table tests targeting piers on the supporting ground and on the developed structure were carried out. Moreover, reproduction analyses of shaking table tests were conducted using a 2D FEM model, and the seismic response of the developed structure was successfully reproduced using the proposed analysis model. © 2020 American Physical Society