Strut-and-tie design methodology for three-dimensional reinforced concrete structures

Journal of Structural Engineering (Impact Factor: 1.49). 06/2006; 132(6). DOI: 10.1061/(ASCE)0733-9445(2006)132:6(929)

ABSTRACT A strut-and-tie design methodology is presented for three-dimensional reinforced concrete structures. The unknown strut-and-tie model is realized through the machinery of a refined evolutionary structural optimization method. Stiffness of struts and ties is computed from an evolved topology of a finite element model to solve statically indeterminate strut-and-tie problems. In addition, compressive strength for struts and nodal zones is evaluated using Ottosen's four-parameter strength criterion. Numerical examples are studied to demonstrate that the proposed design methodology is suitable for developing and analyzing three-dimensional strut-and-tie models for reinforced concrete structures.

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