Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School

Civil Engineering


The design of a Civil Engineering structure has been considered an art based upon science; for though the Strength of Materials formulae give the general solution for the problem, the fact that the particular chosen solution be a good one, relies on the ability of the designer. Indeed, intuition, experience, or just luck are necessary to pick out conveniently the elements that need to be chosen in the formulae. Thus, a confrontation with a design problem requires an answer to the question: What is the optimal (or fairly close to the optimal) solution that can be obtained for the given set of data? It is necessary to define what is to be considered an "optimal solution." Concerning most Civil Engineering designs, it might be "the solution that, fulfilling all technical and aesthetic requirements, is the most economical." Electronic computers have made it possible to get an answer for the stated question within a reasonable period of time. Consequently, mathematical optimization techniques-such as the Random Search that was applied in this work, have become tools to be used in practical life. The development of a design method for of training successive solutions, in such a way that every solution be better than the previous one (so approaching to an optimum), was the aim of this research. In order to illustrate and develop the method, a rather simple design problem was chosen. A more typical, practical problem might perhaps involve more detail, but would not differ in approach. The problem is stated as follows: Optimize, according to the definition given in the Introduction, the design of a two-span rectangular reinforced concrete beam (Figure 1). The design must be in accordance with the ACI Standard-Building Code specifications for Ultimate Strength Design.

Library of Congress Subject Headings

Reinforced concrete




South Dakota State University