Optimal design for rectangular isolated footings using the real soil pressure

Abstract

The standard design method (classical method) for reinforced concrete rectangular footings is: First, a dimension is proposed and should comply with the allowable stresses; subsequently, the effective depth is obtained from the maximum moment and is checked against the bending shear and the punching shear until, it complies with these conditions and, then, steel reinforcement is obtained, but it is not guarantee that the minimum cost will be obtained. This paper shows an optimal design for reinforced concrete rectangular footings using the new model. A numerical experimentation is presented to show the model capability to estimate the minimum cost design of the materials used for a rectangular footing that supports an axial load and moments in two directions in accordance to the building code requirements for structural concrete and commentary (ACI 318-13). Also, a comparison is made between the optimal design and current design for rectangular footings. The solutions show that the optimal design is more economical and more precise with respect to the current design, because standard design is done by trial and error. Then, the optimal design should be used to obtain the minimum cost design for reinforced concrete rectangular footings.

Modelo optimizado para cabezales rectangulares apoyados sobre un grupo de pilotes: Parte 1) Superficie óptima

“…Para las figuras 2c, 2d y 2e, su principal aplicación es para cabezales que soportan una carga axial y dos momentos (dirección X y Y). La ecuación general para obtener el esfuerzo generado en cualquier parte por el suelo sobre las zapatas apoyadas en estratos superficiales (cimentación superficial o poco profundas) sujetas a flexión biaxial es (Gere & Goodo, 2009;López-Chavarría et al, 2017;Luévanos-Rojas et al, 2017;Velázquez-Santillán et al, 2018):…”

Estudio comparativo para áreas mínimas en contacto con el suelo de zapatas aisladas rectangulares y circulares trabajando parcialmente bajo compresión

“…Las investigaciones sobre la capacidad portante de zapatas poco profundas sometidas a flexión biaxial han sido presentadas por: Gonzalez-Garcia [15], Irles-Más and Irles-Más [16], Rodriguez-Gutierrez and Aristizabal-Ochoa [17], Camero [18], Chagoyén et al [19], Ramu and Madhav [20], Özmen [21], Smith-Pardo [22], Valencia et al [23], Rodriguez-Gutierrez and Aristizabal-Ochoa [24,25], Cunha and Albuquerque [26], Luévanos-Rojas [27], Hassaan [28], Momeni et al [29], Camero [30], Kassouf et al [31], Luévanos-Rojas et al [32], Da Silva et al [33], Munévar-Peña et al [34], Rodrigo-García et al [35], López-Chavarría et al [36], Liu and Jiang [37], Al-Abbas et al [38], Gnananandarao et al [39], Alelvan et al [40], Lezgy-Nazargah et al [41], Gör [42], Himeur et al [43].…”

A general model for rectangular footings part I: optimal surface

“…López-Chavarría et al [22] investigated the optimal dimensioning for the corner combined footings. Luévanos-Rojas et al [23] investigated the optimal design for rectangular isolated footings using the real soil pressure. Gandomi and Kashani [24] used the recent swarm intelligence techniques to estimate the construction minimum cost of the shallow foundation.…”