This paper presents a social harmony search algorithm model for the cost optimization of composite floor system with discrete variables. The total cost function includes the costs of concrete, steel beam and shear studs. The design is based on AISC load and resistance factor design specifications and plastic design concepts. Here, six decision variables are considered for the objective function. In order to demonstrate the capabilities of the proposed model in optimizing composite floor system designs, two design examples taken from the literature are studied. It is shown that use of the presented model results in significant cost saving. Hence, it can be of practical value to structural designers. Also the proposed model is compared to the original harmony search, its recently developed variants, and other meta-heuristic algorithms to illustrate the superiority of the present method in convergence and leading to better solutions. In order to investigate the effects of beam spans and loadings on the cost optimization of composite floor system a parametric study is also conducted.

Discrete cost optimization of composite floor system using social harmony search model

This study was funded by the Spanish Ministry of Economy and Competitiveness, along with FEDER funding (DIMALIFE Project BIA2017-85098-R).

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Steel-Concrete Composite Bridges: Design, Life Cycle Assessment, Maintenance, and Decision-Making

The paper presents the cost optimization of the composite I beam floor system. The composite I beam floor system is designed to be constructed up of a reinforced concrete slab and doubly-symmetrical welded steel I beams. The optimization was performed by the nonlinear programming approach, NLP. An accurate objective function of the manufacturing material, power and labour costs was developed and applied for the optimization. The composite I beam floor system was optimized according to Eurocode 4 for the conditions of both the ultimate and the serviceability limit states. A numerical example of the cost optimization of a composite I beam floor system is presented at the end of the paper to expose the advantages of the proposed approach.

Cost Optimization of Composite I Beam Floor System

Because of the increasing demand for curved bridges combined with challenges of design and construction there is need to improve practices for the efficient design and construction of curved bridges This report presents the results of two projects aimed at establishing a curved steel bridge research program within the University of Alabama system: UTCA Project 01223, "Design and Construction of Modern Curved Bridges," and UTCA Project 03228, "Stability of Curved Bridges during Construction" The overall objectives of these projects were to improve design and construction practices, improve economic efficiency, and increase safety by investigating stability issues associated with the construction of horizontally curved bridges Activities of the project included (1) synthesizing curved bridge stability research and state-of-the-art practice, (2) identifying construction stability research needs through contact with the Alabama Department of Transportation (ALDOT), prominent researchers, and industry, and (3) conducting fundamental stability research that will improve curved bridge design and construction methodology The stability of both I- and box-shaped curved girders was considered The planning, design, fabrication, and construction of a local curved I-girder bridge flyover was studied to gain a better understanding of practical challenges associated with curved bridge design and construction Students conducted analytical investigations involving advanced theoretical approaches to solving governing stability equations as well as the use of advanced finite element methods Several papers and presentations resulted The project enabled the investigators to participate in national level conferences and meetings The report provides an in-depth synthesis of literature and current practice related to the design and construction of curved I-girder and box girder bridges and an outline of needs for future research The research literature collected will facilitate continued research efforts Additional technical results of the effort have been and will continue to be disseminated through conference presentations and proceedings, journal publications, and student theses and dissertations

Stability of Curved Bridges During Construction

The application of direct search optimisation to structural design

The practicality of optimization applied to a complex structural design problem is examined using the steel box girder bridge as a case for study. An automated procedure to generate and appraise cost differing layouts for a stiffened, open or closed steel box girder with composite concrete deck is described. Appraisal is based on the merrison interim design rules, CP 117 and BS 153. For comparison, the cost per metre of span is derived from a standard fabricated segment length of 10 M, using a breakdown of operation times with ascribed team plus plant rates and separate costing of material. A direct search technique with external penalty function is used to locate global optima. The procedure is applied to a numerical example in which minimum weight and minimum cost solutions are compared and the effects of changes in span and material grade are noted. It is concluded that the development of meaningful, special purpose, optimization routines for complex structures is possible and can be fruitful in technical and commercial terms provided the aim is to supplement rather than supplant engineering judgement. (A) /TRRL/

D Tordoff

Papers

Optimum design of composite box girder bridge structures.