Life-Cycle Cost Model and Design Optimization of Base-Isolated Building Structures

Design of economic structures adequately resistant to withstand during their service life, without catastrophic failures, all possible loading conditions and to absorb the induced seismic energy in a controlled fashion, has been the subject of intensive research so far. Modern buildings usually contain extremely sensitive and costly equipment that are vital in business, commerce, education and/or health care. The building contents frequently are more valuable than the buildings them-selves. Furthermore, hospitals, communication and emergency centres, police and fire stations must be operational when needed most: immediately after an earthquake. Conventional con-struction can cause very high floor accelerations in stiff buildings and large interstorey drifts in flexible structures. These two factors cause difficulties in insuring the safety of both building and its contents. For this reason base-isolated structures are considered as an efficient alternative design practice to the conventional fixed-base one. In this study a systematic assessment of op-timized fixed and base-isolated reinforced concrete buildings is presented in terms of their initial and total cost taking into account the life-cycle cost of the structures

Innovative Computational Techniques for Multi Criteria Decision Making, in the Context of Cultural Heritage Structures’ Fire Protection: Case Studies

Fire protection for cultural heritage structures is a challenging engineering task that could benefit from the use of specialized computational tools relying on a performance-based design (PBD) concept rather than on prescriptive-based fire protection codes. In the first part of the present study, the theoretical basis of the proposed computational selection and resource (S and R) allocation model is discussed, related to the assessment of the fire safety index (FSI) and the authenticity preservation index (API). Furthermore, two different multi criteria optimization approaches are proposed to generate optimized fire protection upgrading designs, incorporating the nondominated sorting evolution strategies II (NSES-II) algorithm and the analytic target cascading (ATC) method. In this second part of the present work, the proposed S and R allocation model is implemented in two test cases; Villa Bianca, a famous mansion in Thessaloniki, Greece, and the Monastery of Simonos Petra located in Mount Athos, Greece. Several cases are examined regarding the targeted FSI or API values, taking also into account budget restrictions. In cases where the preservation of the authenticity is considered as an objective within the design process, the need to implement more sophisticated and customized fire protection measures can lead to a significant increase up to almost 200% regarding the total cost, subject to the pursued safety level. Detailed results obtained for each case study are presented and discussed comparatively, demonstrating the efficiency of the proposed S and R allocation model in a wide range of scenarios, as well as its possible utility in multiple applications, facilitating the fire protection design process. Finally, a comparison between the two multi criteria optimization approaches incorporated in the study is also presented and discussed

Innovative Computational Techniques for Multi Criteria Decision Making, in the Context of Cultural Heritage Structures’ Fire Protection: Case Studies

Fire protection for cultural heritage structures is a challenging engineering task that could benefit from the use of specialized computational tools relying on a performance-based design (PBD) concept rather than on prescriptive-based fire protection codes. In the first part of the present study, the theoretical basis of the proposed computational selection and resource (S and R) allocation model is discussed, related to the assessment of the fire safety index (FSI) and the authenticity preservation index (API). Furthermore, two different multi criteria optimization approaches are proposed to generate optimized fire protection upgrading designs, incorporating the nondominated sorting evolution strategies II (NSES-II) algorithm and the analytic target cascading (ATC) method. In this second part of the present work, the proposed S and R allocation model is implemented in two test cases; Villa Bianca, a famous mansion in Thessaloniki, Greece, and the Monastery of Simonos Petra located in Mount Athos, Greece. Several cases are examined regarding the targeted FSI or API values, taking also into account budget restrictions. In cases where the preservation of the authenticity is considered as an objective within the design process, the need to implement more sophisticated and customized fire protection measures can lead to a significant increase up to almost 200% regarding the total cost, subject to the pursued safety level. Detailed results obtained for each case study are presented and discussed comparatively, demonstrating the efficiency of the proposed S and R allocation model in a wide range of scenarios, as well as its possible utility in multiple applications, facilitating the fire protection design process. Finally, a comparison between the two multi criteria optimization approaches incorporated in the study is also presented and discussed

Innovative Computational Techniques for Multi-Criteria Decision Making, in the Context of Cultural Heritage Structures’ Fire Protection: Theory

The preservation of cultural heritage structures includes, among others, an efficient fire protection design process. This engineering design process frequently generates critical decision making issues related to conflicts that involve the buildings’ authenticity preservation, the implementation of special fire protection measures and addressing the particular needs of such structures. However, conventional approaches based on prescriptive regulations are often problematic in such cases; on the contrary, Performance-Based (PB) approaches could successfully deal with such structures to deliver designs that satisfy an acceptable fire safety level, and at the same time minimize the cost and any interventions on the building’s appearance, to the extent that authenticity is a key demand. Thus, in this study the upgrade of the fire safety level of cultural heritage structures is expressed as a Multi-Criteria Decision Making (MCDM) problem. Accordingly, the Analytic Hierarchy Process (AHP) is incorporated into a new fire protection Selection and Resource (S&R) allocation model, aiming to assess both fire safety and authenticity preservation levels with reference to the protection measures selected. Furthermore, in this study two different multi-criteria optimization approaches are applied to generate optimized solutions of the fire safety upgrading scheme. In this first part of the study, the theoretical basis of the proposed S&R allocation model that relies on a MCDM problem and how to deal with is discussed, while in the second part the implementation of the proposed model is presented for two real-world test cases. More specifically, in this study the theoretical part of the multi-objective and the multi-disciplinary problems (belonging to the MCDM type of problems) is provided with respect to the problems’ description and the methods adopted for solving the corresponding problems