Betonarme İstinat Duvarlarının Çiçeklerin Tozlaşma Algoritması İle Optimizasyonu

Konferans Bildirisi -- Teorik ve Uygulamalı Mekanik Türk Milli Komitesi, 2015Conference Paper -- Theoretical and Applied Mechanical Turkish National Committee, 2015Bir mühendisin ana amacı güvenlik ve ekonomik koşulları sağlayan en iyi sonucu bulmaktır. Bundan dolayı, optimizasyon çeşitli tasarım değişkenleri ve kısıtlarının bulunduğu mühendislik problemlerinin tasarımında gereklidir. Optimizasyonda, doğal olaylardan ilham alan metasezgisel algoritmalar optimum çözümlerin bulunmasında oldukça etkilidir. Bu çalışmada, yakın zamanda geliştirilen ve çiçek açan bitkilerin tozlaşma sürecinden esinlenen çiçeklerin tozlaşma algoritması kullanılmıştır. Betonarme istinat duvarları boyut ve donatı değişkenleri için optimize edilmiştir. Ayrıca, optimizasyon problemi devrilme, kayma ve taban basıncı kontrollerini de içermektedir. Önerilen metot minimum maliyetli optimum tasarımın bulunmasında olasıdır.The main aim of an engineer is to find the best solution ensuring security and economical conditions. Thus, optimization is needed in design of engineering problems with various design variables and constraints. In optimization, the metaheuristic methods inspired by natural happenings are very effective on finding optimum solutions. In this study, recently developed flower pollination algorithm inspired by the pollination process of flowering plants is employed. Reinforced concrete retaining walls are optimized for dimension and reinforcement design variables. The optimization problem also considers turnover, slip and base stress controls of the retaining walls. The proposed method is feasible to find optimum design with the minimum cost

Metaheuristic algorithms in optimum design of reinforced concrete beam by investigating strength of concrete

The locations of structural members can be provided according to architectural projects in the design of reinforced concrete (RC) structures. The design of dimensions is the subject of civil engineering, and these designs are done according to the experience of the designer by considering the regulation suggestions, but these dimensions and the required reinforcement plan may not be optimum. For that reason, the dimensions and detailed reinforcement design of RC structures can be found by using optimization methods. To reach optimum results, metaheuristic algorithms can be used. In this study, several metaheuristic algorithms such as harmony search, bat algorithm and teaching learning-based optimization are used in the design of several RC beams for cost minimization. The optimum results are presented for different strength of concrete. The results show that using high strength material for high flexural moment capacity has lower cost than low stretch concrete since doubly reinforced design is not an optimum choice. The results prove that a definite metaheuristic algorithm cannot be proposed for the best optimum design of an engineering problem. According to the investigation of compressive strength of concrete, it can be said that a low strength material are optimum for low flexural moment, while a high strength material may be the optimum one by the increase of the flexural moment as expected

Metaheuristic optimization of reinforced concrete footings

The primary goal of an engineer is to find the best possible economical design and this goal can be achieved by considering multiple trials. A methodology with fast computing ability must be proposed for the optimum design. Optimum design of Reinforced Concrete (RC) structural members is the one of the complex engineering problems since two different materials which have extremely different prices and behaviors in tension are involved. Structural state limits are considered in the optimum design and differently from the superstructure members, RC footings contain geotechnical limit states. This study proposes a metaheuristic based methodology for the cost optimization of RC footings by employing several classical and newly developed algorithms which are powerful to deal with non-linear optimization problems. The methodology covers the optimization of dimensions of the footing, the orientation of the supported columns and applicable reinforcement design. The employed relatively new metaheuristic algorithms are Harmony Search (HS), Teaching-Learning Based Optimization algorithm (TLBO) and Flower Pollination Algorithm (FPA) are competitive for the optimum design of RC footings

Effect of feedback on PID controlled active structures under earthquake excitations

In this paper, different feedback control strategies are presented for active seismic control using proportional-integral-derivative (PID) type controllers. The parameters of PID controller are found by using an numerical algorithm considering time delay, maximum allowed control force and time domain analyses of shear buildings under different earthquake excitations. The numerical algorithm scans combinations of different controller parameters such as proportional gain (K-p), integral time (T-i) and derivative time (T-d) in order to minimize a defined response of the structure. The controllers for displacement, velocity and acceleration feedback control strategies are tuned for structures with active control at the first story and all stories. The performance and robustness of different feedback controls on time and frequency responses of structures are evaluated. All feedback controls are generally robust for the changing properties of the structure, but acceleration feedback control is the best one for efficiency and stability of control system

Control Of Structures With Active Tendons

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2007Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2007Bu çalışmada, tek serbestlik ve çok serbestlik dereceli bina modellerine Orantı+İntegral+Türev tipi kontrolcü ile birlikte çalışan aktif tendonlar uygulanmıştır. İlk önce, binanın fiziksel modeli sanal yaylar, sönümleyiciler ve rijit kütleler ile oluşturulmuştur. Bu aşamadan sonra, sistemlerin potansiyel, kinetik ve sönüm enerjisi belirlenmiştir. Sistemlerin hareket denklemleri, Lagrange denklemlerini kullanarak elde edilmiştir.Hareket denklemlerinin blok diyagramlarının elde etmek için Matlab programının alt programı olan Simulink kullanılmıştır. Orantı işlemi, hızlı cevap vermeye yarar. Türev işlemi, sönümleme kararlılığı için iyidir. İntegral işlemi, istenen sabit durumlu cevabı elde etmeye yardımcı olur. Bu işlemler için parametreler, deneme yanılma yöntemi ile bulunmuştur.Düzce depremi (1999), sisteme giriş olarak etki ettirtmek için seçilmiştir. Düzce depremi darbe tipi bir depremdir. Bu depremin üç ayrı merkezdeki kaydı incelenmiştir. Bunlar faya yakın olan Bolu ve daha uzak olan Sakarya ve İstanbul’da kaydedilmiş datalardır. Ayrıca, ilginç ivme datası nedeniyle Erzincan depremi (1992) de seçilmiştir. Bu depremin Erzincan kaydı kullanılmıştır. Bu durumda yakın ve uzak fay etkisi görülmüştür.Deprem ivme dataları sisteme uygulandıktan sonra, deplasman, hız, ivme ve transfer fonksiyonları gibi yapıda oluşan büyüklükler tüm serbestlik dereceleri için analiz edilmiştir. Deplasman – zaman, hız – zaman, ivme – zaman ve transfer fonksiyonu (Db) – frekans (Hz) grafikleri üzerinde kontrol edilmeyen ve edilen binalar karşılaştırılmıştır. Ayrıca tendonların çeşitli kombinasyonları incelenmiştir. Sonuçlar metodun uygulanabilir olduğunu göstermiştir.In this study, active tendons with Proportional Integral Derivation type controllers were applied to a SDOF and a MDOF building model. First, physical models of buildings were constituted with virtual springs, dampers and rigid masses. After this stage, potential, kinetic and damping energy of the systems were defined. Equations of motion of systems were obtained using the Lagrange Equations. Matlab Simulink was utilized to obtain the block diagrams for the equations of motion. P-action is introduced for increasing the speed of response. D-action is introduced for damping purposes. I-action is introduced for obtaining a desired steady-state response. Parameters for these actions were found by using trial method. Duzce Earthquake (1999) was chosen to apply as an input of systems. This earthquake was a stroke type. This earthquake’s different records such as Bolu, Sakarya and Istanbul were examined. Bolu is near to the main fault and the others far from it. Also, Erzincan Earthquake (1992) was chosen because of its interesting acceleration data. Erzincan record of this earthquake was examined. In this situation, near and far fault effect was also examined. After earthquake acceleration data were applied to the system, building parameters such as displacements, velocities, accelerations and transfer functions were analyzed for all degrees of freedom. Comparisons on displacement vs. time, velocity vs. time, acceleration vs. time and transfer function (Db) vs. frequency (Hz) were made for uncontrolled and controlled buildings. Also, various combinations of the tendons were examined. The results show that the method seems feasible.Yüksek LisansM.Sc