Feasibility study of the construction of foundations with a convex upward curved shape of the contact surface

Abstract

In the article the comparison of the two technologies of foundations: the traditional technology of cast-in-situ solid slab Foundation and the alternative technology foundations with the upward-convex curved shape of the contact surface. The foundation with an upward curved contact surface is a geometrically complex structure consisting of monolithic belts (support contours), united by flat cylindrical shells convex upwards with respect to the ground, made along the curved surface of the soil mass with an undisturbed natural structure. Due to the joint work of monolithic belts and a reinforced concrete shell located in the span of the foundation, made along the curved contact surface of the ground mass, this foundation structure is an alternative to a solid slab foundation. When the support contours are drained under load, the reinforcement of the shell is tensioned, the soil under the shell is compressed and thus the soil is involved in the work, which allows increasing the strength characteristics of the foundation and reducing the overall draft of the building. The author of the article describes the structural and technological features of this type of foundation. Due to the complex geometric shape of the foundation under study, the total labor costs and the duration of the work increase in the construction practice. As part of the study, two types of foundations were compared according to technological and economic indicators, using the example with the specified geometric parameters. As a result of the obtained data, an increase in labor costs for performing manual molding of the soil mass and the device of a monolithic convex up shell of the foundation in comparison with the traditional technology of the device of a solid slab foundation was revealed. But at the same time, a reduction in direct costs by 30 % was revealed in the construction of a band-shell foundation, due to a reduction in the consumption of steel and concrete, which determines the effectiveness of this type of foundation and expands its scope in the construction of buildings and structures.