Fuzzy Sets Applications in Civil Engineering Basic Areas

Civil engineering is a professional engineering discipline that deals with the design, construction, and maintenance of the physical and naturally built environment, including works like roads, bridges, canals, dams, and buildings. This paper presents some Fuzzy Logic (FL) applications in civil engeering discipline and shows the potential of facilities of FL in this area. The potential role of fuzzy sets in analysing system and human uncertainty is investigated in the paper. The main finding of this inquiry is FL applications used in different areas of civil engeering discipline with success. Once developed, the fuzzy logic models can be used for further monitoring activities, as a management tool

Optimal seismic retrofitting of existing RC frames through soft-computing approaches

2016 - 2017Ph.D. Thesis proposes a Soft-Computing approach capable of supporting the engineer judgement in the selection and design of the cheapest solution for seismic retrofitting of existing RC framed structure. Chapter 1 points out the need for strengthening the existing buildings as one of the main way of decreasing economic and life losses as direct consequences of earthquake disasters. Moreover, it proposes a wide, but not-exhaustive, list of the most frequently observed deficiencies contributing to the vulnerability of concrete buildings. Chapter 2 collects the state of practice on seismic analysis methods for the assessment the safety of the existing buildings within the framework of a performancebased design. The most common approaches for modeling the material plasticity in the frame non-linear analysis are also reviewed. Chapter 3 presents a wide state of practice on the retrofitting strategies, intended as preventive measures aimed at mitigating the effect of a future earthquake by a) decreasing the seismic hazard demands; b) improving the dynamic characteristics supplied to the existing building. The chapter presents also a list of retrofitting systems, intended as technical interventions commonly classified into local intervention (also known “member-level” techniques) and global intervention (also called “structure-level” techniques) that might be used in synergistic combination to achieve the adopted strategy. In particular, the available approaches and the common criteria, respectively for selecting an optimum retrofit strategy and an optimal system are discussed. Chapter 4 highlights the usefulness of the Soft-Computing methods as efficient tools for providing “objective” answer in reasonable time for complex situation governed by approximation and imprecision. In particular, Chapter 4 collects the applications found in the scientific literature for Fuzzy Logic, Artificial Neural Network and Evolutionary Computing in the fields of structural and earthquake engineering with a taxonomic classification of the problems in modeling, simulation and optimization. Chapter 5 “translates” the search for the cheapest retrofitting system into a constrained optimization problem. To this end, the chapter includes a formulation of a novel procedure that assembles a numerical model for seismic assessment of framed structures within a Soft-Computing-driven optimization algorithm capable to minimize the objective function defined as the total initial cost of intervention. The main components required to assemble the procedure are described in the chapter: the optimization algorithm (Genetic Algorithm); the simulation framework (OpenSees); and the software environment (Matlab). Chapter 6 describes step-by-step the flow-chart of the proposed procedure and it focuses on the main implementation aspects and working details, ranging from a clever initialization of the population of candidate solutions up to a proposal of tuning procedure for the genetic parameters. Chapter 7 discusses numerical examples, where the Soft-Computing procedure is applied to the model of multi-storey RC frames obtained through simulated design. A total of fifteen “scenarios” are studied in order to assess its “robustness” to changes in input data. Finally, Chapter 8, on the base of the outcomes observed, summarizes the capabilities of the proposed procedure, yet highlighting its “limitations” at the current state of development. Some possible modifications are discussed to enhance its efficiency and completeness. [edited by author]XVI n.s

Applied Metaheuristic Computing

For decades, Applied Metaheuristic Computing (AMC) has been a prevailing optimization technique for tackling perplexing engineering and business problems, such as scheduling, routing, ordering, bin packing, assignment, facility layout planning, among others. This is partly because the classic exact methods are constrained with prior assumptions, and partly due to the heuristics being problem-dependent and lacking generalization. AMC, on the contrary, guides the course of low-level heuristics to search beyond the local optimality, which impairs the capability of traditional computation methods. This topic series has collected quality papers proposing cutting-edge methodology and innovative applications which drive the advances of AMC

Artificial Neural Network Approaches For Slope Stability

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2007Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2007Bu çalışmada 170 tane lokal bölgenin şev profili dataları kullanılarak yapay zeka mantığı yaklaşımlarından beş tane yapay sinir ağı mimarisi kullanılmıştır. Bunlar BPNN, geri yayılmalı sinir ağı mimarisi ve GRNN, genel regresyonlu yapay sinir ağı mimarisi, GMDH, gruplama methodu, Kohonen ve PNN, olasılık yöntemidir. Ancak sadece BPNN, geri yayılmalı sinir ağı mimarisi ve GRNN, genel regresyonlu yapay sinir ağı mimarisi model oluşturmakta kullanılmıştır. Bu yaklaşımlarda 9 adet girdi ve 1 tane çıkış parametreleri verilmiştir. Çıkış parametresi şev güvenlik katsayısı olup, girdi parametreleri şev yüksekliği ( H ), şev eğimi ( β ), yeraltı suyu derinliği ( Hw ), sağlam zemin derinliği ( Hb ), kohezyon ( c ), zemin içsel sürtünme açısı ( Φ ), kuru birim hacim ağırlığı ( γ ), düşey ve yatay sismik zemin katsayıları ( Kh , Kv )‘dır. Bu çalışmadaki amaç sismik zemin katsayılarının şev stabilitesindeki önemlerinin incelenmesidir. Sonuç olarak genel regresyon yapay sinir ağı modelinin daha başarılı olduğu ve % 92.5 başarı yüzdesine sahip olduğu görülmüş, düşey ve yatay sismik zemin katsayılarının şev yüksekliği, şev eğimi ve yeraltı suyu derinliğinden sonra şev stabilitesindeki etkisinin önemli olduğu görülmüştür.In this study 170 slope data and their properties are used by Artificial Intelligence approach five neural network approaches architecture These approaches are Back propagation neural network architecture ( BPNN ), General regression neural network ( GRNN ), Group method of data handling ( GMDH ), Kohonen learning paradigm and Probabilistic neural network ( PNN ) architectures. But only 2 of them used, these are the back propagation neural network architecture ( BPNN ) and the general regression neural network ( GRNN ). There are 9 input parameters and 1 output parameter. The output parameter is the factor of the safety of the slopes ( F.S. ), the input parameters are the height of slope ( H ), the inclination of slope ( β ), the height of water level ( Hw ), the depth of firm base ( Hb ), the cohesion of soil ( c ), the friction angle of soil ( Φ ), the unit weight of soil ( γ ), but the important input parameters are horizontal and vertical seismic coefficients ( kh , kv ).Trying to be obtained in this study is to see the importance of the seismic coefficients for a slope stability safety. In conclusion this study shows that general regression neural network (GRNN) approach is more useful model and have % 92.5 success rate for seeing the effect of earthquake for slope stability safety and generally horizontal and vertical seismic coefficients importance seen after the height of the slope ( H ), the inclination of slope ( β ), the height of water level (Hw) importance.Yüksek LisansM.Sc

Προηγμένες υπολογιστικές μέθοδοι αντισεισμικού σχεδιασμού και αποτίμησης κατασκευών από οπλισμένο σκυρόδεμα

309 σ.Ο κύριος στόχος της διατριβής ήταν η ανάπτυξη ενός ολοκληρωμένου πλαισίου για την αξιολόγηση και τον οικονομικό-ασφαλή αντισεισμικό σχεδιασμό κατασκευών. Αυτός ο καθολικός στόχος της διατριβής επετεύχθη μέσω των ακόλουθων βημάτων: (i) Στο πρώτο μέρος της διατριβής πραγματοποιήθηκε αριθμητική βαθμονόμηση ορισμένων από τους πιο δημοφιλείς δείκτες βλάβης που έχουν προταθεί και υιοθετηθεί από πολλούς ερευνητές προκειμένου να προσδιορίσουν το επίπεδο ζημίας κατασκευών από οπλισμένο σκυρόδεμα. (ii) Στο δεύτερο στάδιο της διατριβής πραγματοποιήθηκε αξιολόγηση των περιγραφικών διαδικασιών αντισεισμικού σχεδιασμού σε σχέση με τον συντελεστή συμπεριφοράς που υιοθετείται από τους Ευρωκώδικες και διερευνήθηκε η βέλτιστη επιλογή που οδηγεί στον οικονομικότερο και ασφαλέστερο σχεδιασμό. Επιπροσθέτως έγινε σύγκριση των μεθόδων σχεδιασμού με βάση την επίδοση σε σχέση με τις περιγραφικές μεθόδους σχεδιασμού. Στη συνέχεια, με βάση τους βαθμονομημένους δείκτες βλάβης, διατυπώθηκαν προβλήματα βελτιστοποίησης με στόχο να προσδιοριστεί ο δείκτης βλάβης ή ο συνδυασμός δεικτών βλάβης που αποτελούν την σωστότερη επιλογή προκειμένου να ενσωματωθεί στο πλαίσιο σχεδιασμού που βασίζεται στην επιτελεστικότητα. (iii) Ως επόμενο βήμα της διατριβής ήταν η βελτίωση της διαδικασίας του κόστους κύκλου ζωής όσον αφορά την αξιοπιστία και την υπολογιστική αποδοτικότητά της.. (iv) Ο τελευταίος στόχος της διατριβής ήταν η βελτίωση της διαδικασίας ανάλυσης τρωτότητας σε σχέση με την αξιοπιστία και την υπολογιστική αποδοτικότητα. Η υπολογιστική αποδοτικότητα επετεύχθη μέσω της προτεινόμενης στο πλαίσιο της παρούσης διατριβής προσαυξητικής δυναμικής ανάλυσης με βάση πρόβλεψης νευρωνικών δικτύων η οποία μειώνει τις υπολογιστικές απαιτήσεις κατά μία τάξη μεγέθους.The major objective of this Dissertation is to develop an integrated framework for the economical and safe antiseismic design and assessment of new reinforced concrete structures by means of life-cycle cost and fragility analysis. This objective of the dissertation is achieved through the accomplishment of the following tasks: (i) At the first part of the Dissertation numerical calibration for some of the most popular damage indices (DIs) that have been proposed by many researchers was performed, in order to quantify the extent of damage in reinforced concrete structures. (ii) A critical assessment of prescriptive design procedures was performed with reference to their ability to lead to safe and economical designs. Furthermore, a comparison between prescriptive and performance-based seismic design procedures was carried out. For this purpose a number of structural seismic design optimisation problems have been formulated. On the other hand, based on the calibrated DIs, structural optimization problems were formulated aiming at identifying the DI, or the combination of Dis that will provide reliable information on damage so that they can be incorporated into a Performance-Based Design framework. The ultimate objective of this task is to compare lower-bound designs that satisfy the design code requirements in the most cost-effective way using a Life-Cycle Cost Analysis (LCCA) methodology. (iii) The next step is to improve the LCCA procedure with reference to both its robustness and efficiency. (iv) The last objective of the dissertation is to improve the fragility analysis procedure with reference to both robustness and efficiency. The efficiency is achieved by introducing a neural network-based incremental dynamic analysis (IDA) procedure that reduces the computational effort by one order of magnitude.Χαρίκλεια Χ. Μητροπούλο

Internationales Kolloquium über Anwendungen der Informatik und Mathematik in Architektur und Bauwesen : 20. bis 22.7. 2015, Bauhaus-Universität Weimar

The 20th International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering will be held at the Bauhaus University Weimar from 20th till 22nd July 2015. Architects, computer scientists, mathematicians, and engineers from all over the world will meet in Weimar for an interdisciplinary exchange of experiences, to report on their results in research, development and practice and to discuss. The conference covers a broad range of research areas: numerical analysis, function theoretic methods, partial differential equations, continuum mechanics, engineering applications, coupled problems, computer sciences, and related topics. Several plenary lectures in aforementioned areas will take place during the conference. We invite architects, engineers, designers, computer scientists, mathematicians, planners, project managers, and software developers from business, science and research to participate in the conference

The 1st International Electronic Conference on Algorithms

This book presents 22 of the accepted presentations at the 1st International Electronic Conference on Algorithms which was held completely online from September 27 to October 10, 2021. It contains 16 proceeding papers as well as 6 extended abstracts. The works presented in the book cover a wide range of fields dealing with the development of algorithms. Many of contributions are related to machine learning, in particular deep learning. Another main focus among the contributions is on problems dealing with graphs and networks, e.g., in connection with evacuation planning problems