The cutting stock problem with diameter conversion inthe construction industry

Altınpulluk, Deniz
The one-dimensional cutting stock problem has been widely used for reinforcementsteel bar (rebar) in the construction industry. Diameter sizes of rebars are determinedby the structural designer to provide tensile strength to the structure, and they can bechanged if the ratio of cross-section area of rebars to the concrete area stays constant.The decision maker can decide to convert diameter size to generate better cuttingpatterns. Besides, the time dimension is considered by assuming the multi-periodstructure of rebar demand. We study the cutting stock problem that decides diametersizes, cutting times, and cutting patterns to minimize the usage of raw material andholding cost. It differs from the classical cutting stock problem as it is not knownhow many pieces should be cut until diameter sizes are chosen. We propose a pseudo-polynomial formulation and a genetic algorithm to solve the problem. Computationalresults are provided.


Two dimensional cutting stock problem with multiple stock sizes
Ayasandır, Umutcan; Azizoğlu, Meral; Department of Industrial Engineering (2019)
In this study, we consider a two dimensional cutting stock problem with multiple stock sizes and two stage guillotine cuts. Our objective is to maximize the difference between total revenue over all items and total cost over all used panels. We propose two mathematical models and discuss their relative performances. We enhance the performances of the models by incorporating the properties of optimal solution that we derive. The results of our computational study have revealed the satisfactory performance of...
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Özşahin, Orkun; Özgüven, Hasan Nevzat; Department of Mechanical Engineering (2008)
In machining centers, with the increasing trends in high precision machining, chatter has become an important problem which results in poor surface finish and low material removal rate. Chatter can be avoided with stability diagrams which provide the stable regions in the machining process for the depth of cut and spindle speed combinations. In order to obtain stability diagrams, tool point frequency response function (FRF) of the system should be obtained. Throughout this study, contact parameters which ar...
Analysis of tube upsetting
Tüzün, Aydın; Darendeliler, Haluk; Department of Mechanical Engineering (2004)
Producing axi-symmetrical parts with holes from tubular stock by tube upsetting is a frequently used technique in industry. There are basically four types of tube upsetting process; external, internal, simultaneous internal and external upsetting, and expanding of tube. In general, tubular parts require more than one upsetting stage. In industry, generally trial-error methods, which require lots of time and effort depending on experience, are used for the design of stages. Wrong design causes failures durin...
A disassembly line balancing problem with fixed number of workstations
Kalaycilar, Eda Goksoy; Azizoğlu, Meral; Yeralan, Sencer (2016-03-01)
In this study, a Disassembly Line Balancing Problem with a fixed number of workstations is considered. The product to be disassembled comprises various components, which are referred to as its parts. There is a specified finite supply of the product to be disassembled and specified minimum release quantities (possible zero) for each part of the product. All units of the product are identical, however different parts can be released from different units of the product. There is a finite number of identical w...
The influence of thickness/grain size ratio in microforming through crystal plasticity
Bulut, Orhun; Acar, Sadik Sefa; Yalçınkaya, Tuncay (2021-01-01)
Microscale forming operations have become popular due to miniaturisation which focuses on micro scale design and manufacturing of devices, components and parts, e.g. in RF-MEMS. In such processes when the component dimension becomes comparable with the grain size, considerable size effect is observed. Recent experimental studies on micron sized sheet specimens have shown that the ratio between thickness (t) and grain size (d) has a significant influence on the mechanical behavior of materials which cannot b...
Citation Formats
D. Altınpulluk, “The cutting stock problem with diameter conversion inthe construction industry,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Industrial Engineering., Middle East Technical University, 2019.