Lateral loading resistance for shell foundations

Abstract

ABSTRACT Shell foundations, or geometrically shaped footings, were first used as a substitute for the conventional flat shallow foundations in the nineteen fifties in Mexico, West Germany, India, China and the Soviet Union. It is not known whether their use was developed independently or was incorporated after observing their use elsewhere. However, it is certain that their use was not based on any research data that has been reported at that time. Since then, the use of shell foundations has drawn considerable interest around the world. Experimental and theoretical investigations by the author on ‘shell type’ foundations have shown significant increases in bearing capacity, better settlement characteristics, and ability to resist higher lateral forces which might be induced due to wind loads or earthquakes as compared to the conventional flat foundations. This is primarily due to partial absorption of the vertical load through lateral compression of the soil particles under the shell. Given these attributes, the practical implications could make shell foundations ideally suited for foundations subjected to lateral loadings. It is also known that shell foundations require less construction materials, which could benefit its use in developing countries where materials are scarce and expensive while labor is abundant and inexpensive. This paper presents analytical analysis of shell and flat foundations subjected to lateral loading. The results of this study will be presented in the form of a comparative study and numerical example, which will demonstrate that shell foundations are superior to resist lateral loading.