Ultimate Bearing Capacity of Triangular Shell Strip Footings on Sand

Shells entered into foundation engineering in the mid‐1950s in different parts of the world. Shell foundations have been used as an alternative to the conventional flat shallow foundations. They can be geometrically shaped in elevation, triangular, cylindrical, parabolic, etc., for continuous footings, and conical, spherical, hyperbolic‐paraboloid, etc., for isolated footings. In the literature no reports can be found in which the geotechnical behavior of shell foundations has been evaluated. This paper presents experimental and theoretical investigations of triangular shell strip footings on sand. The results of this study indicate that these footings provide higher bearing capacity and produce less settlement when compared to conventional flat foundations. The classical bearing capacity theory for flat shallow foundations was extended for triangular shell strip footings, and design charts for the modified bearing capacity coefficients are presented for the triangular case. Although there have been rapid advances in efficiency, reliability, and economy in the fields of construction technology and assembly of precast concrete units, the use of shell foundations is still limited by their economics. However, there is potential for the use of shell foundations as an alternative to the conventional flat foundations in the future.