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The aim of this study is to question the relationship between architectural ethical codes and faults in earthquakes. Earthquakes have devastating effects on all societies in history and today. And the relationship and importance of the architect and building, one of the most important roles of these destructive effects, is once again revealed in every earthquake. Although there are some restrictions or warnings for architects and the architectural profession to reduce this destructive effect in many regulations and ethical codes, it is possible to see the defects caused by architectural design and the destruction caused by these defects in every new earthquake.

In this study, the most destructive earthquakes in Turkey in the past 20 years (Bingöl, Van, Elazig and Izmir) and the 1999 Marmara earthquake, which was the most destructive earthquake in Turkey’s recent history, and the damages occurred in these earthquakes and their causes were examined. Although the scope of the study is “destructive earthquakes that have occurred in the past 20 years in Turkey”, the Marmara Earthquake, which occurred in 1999, when the destructive effect of the earthquake was seen the most and architectural design errors were intense, was also included in the scope of the study. And to have a more comprehensive understanding of how these defects are examined in terms of ethical codes and to make a more comprehensive comparison, ethical codes from different countries in the world have been researched and a review has been made on topics such as public welfare, human rights and raising the standard of the profession.

This study concludes by reviewing the key factors learned from the examined ethical codes of different countries. Finding ethical codes of different countries was challenging to gain approval. In addition, the study ends with recommendations in terms of questioning the regulations and education curriculum relations on a country basis.

This study, which targets architect candidates who carry out the profession of architecture and continue their architectural education, evaluates the architectural design flaws seen in earthquakes through ethical codes and forms a basis for further studies.

The purpose of this research is to show significant points which can be used in the architectural design process by investigating the basic principles of earthquake resistant design (ERD) in a deductive format and to contribute to the architectural perception in ERD.

First, the structural irregularity types are examined depending on the rules defined in the Turkish Earthquake Code, 2007 (TEC). Then, architectural design failures related to earthquake resistance of buildings under earthquake loading are visualized and solution suggestions in literature are described in detail by supported drawings.

The problems causing structural irregularities are investigated deeply with given solutions in literature. It is obtained that the significant factors affecting the earthquake performance of structures are: architectural form, structural configuration, slenderness ratio, the location and rate of floor openings, projection rates and symmetry, rigidity and strength differences between floors, short columns, pounding effect. Social implications – The practical design decision rules can contribute to the phenomena of earthquake resistant architectural design and can encourage adoption of these rules in building industry.

This study aims to gain an understanding of the problems in projects in terms of structural irregularities, and then manage to solve the problems using problem‐oriented approaches. The suggested solutions can be adopted and applied to future projects for designing earthquake resistant buildings.

This study aims to present the variations of optimal seismic control of reinforced cement concrete (RCC) structure using different structural systems. Different third-dimensional mathematical models are used to examine the responses of multistory flexibly connected frames subjected to earthquake excitations.

This paper examined a G + 50 multi-storied high-rise structure, which is analyzed using different combinations of moment resistant frames, shear walls, seismic outrigger systems and seismic dampers to observe the effectiveness during ground motion against soft soil conditions. The damping coefficients of added dampers, providing both upper and lower levels are taken into consideration. A finite element modeling and analysis is generated. Then the nature of the structure exposed to ground motion is captured with response spectrum analysis, using BNBC-2020 for four different seismic zones in Bangladesh.

The response of the structure is investigated according to the amplitude of the displacements, drifts, base shear, stiffness and torsion. The numerical results indicate that adding dampers at the base level can be the most effective against seismic control. However, placing an outrigger bracing system at the middle and top end with shear wall can be the most effective for controlling displacements and drifts.

The response of high-rise structures to seismic forces in Bangladesh’s soft soil conditions is examined at various levels in this study. This study is an original research which contributes to the knowledge to build earthquake resisting high-rises in Bangladesh.

This paper aims to present the approximate limit pressure solutions for thin-walled shape-imperfect 90° pipe bends. Limit pressure was determined by finite element (FE) limit analysis with the consideration of small geometry change effects.

The limit pressure of 90° pipe bends with ovality and thinning has been evaluated by geometric linear FE approach. Internal pressure was applied to the inner surface of the FE pipe bend models. When von-Mises stress equals or just exceeds the yield strength of the material, the corresponding pressure was considered as the limit pressure for all models. The current FE methodology was evaluated by the theoretical solution which has been published in the literature.

Ovality and thinning produced a significant effect on thin-walled pipe bends. The ovality weakened pipe bend performance at any constant thinning, while thinning improved the performance of the bend portion at any constant ovality. The limit pressure of pipe bends under internal pressure increased with an increase in the bend ratio and decreased with an increase in the pipe ratio. With a simultaneous increment in bend radius and reduction in wall thickness, there was a reduction in limit pressure. A new closed-form empirical solution was proposed to evaluate limit pressure, which was validated with published experimental data.

The influences of structural deformation (ovality and thinning) in the limit pressure analysis of 90° pipe bends have not been investigated and reported.

Separately, nonlinear finite element analysis, artificial neural networks (ANNs) and continuous damage mechanics (CDM) attracted many investigators to model masonry infilled frames. The purpose of this paper is to pursue four phases to develop a versatile model for partially and fully low-rise infilled RC frames using these tools.

The first phase included the study of the behavior of 1,620 low-rise infilled reinforced concrete frames using macro-scale nonlinear pushover finite element analysis. The approach helped to explore the effects of imposing different masonry infill distributions for one of the typical models of school buildings in Egypt. The outputs of this phase were used in the second phase for the development of an ANN model where input neurons included number of stories, continuity conditions, frame geometry, infill distribution and properties of RC sections. The third phase included the employment of the notions of CDM on the structural scale. Monitoring frames’ stiffness degradation allowed for damage variables identification. In the fourth phase, the simpler equivalent static lateral load (ESLL) for elastic analysis was employed in conjunction with ANN and CDM to obtain the capacity curves for partially and fully low-rise infilled RC frames.

The obtained capacity curves were compared with the nonlinear finite element results. The close agreement of all curves indicated how rigorous, yet simple, the suggested solution procedure is.

The study is concerned with an important type of service buildings. These are the school buildings of Egypt.

The paper presents a combination of four phases that include FE analysis, ANNs, ESLL, and CDM to obtain the capacity curves for partially and fully low-rise infilled RC frames. Such a combination of approaches in tackling a practical problem related to service buildings is innovative and deserves research interest.

School buildings have suffered disproportionate damage during past and recent earthquakes. For example, during the 2008 Sichuan earthquake, many school buildings collapsed, resulting in loss of life. School buildings in many other parts of the world are also susceptible to this type of widespread damage because of inadequate design, detailing, or poor construction quality. The purpose of this paper is to show how these fatal flaws can be mitigated prior to future catastrophe by using good engineering practice to retrofit vulnerable schools.

Conventional and innovative, cost‐effective, and reliable tools are available to prevent damage to schools. It is often necessary to examine a group of buildings or all structures in a locality and develop a comprehensive risk management plan for the vulnerable buildings. As an example, a comprehensive evaluation and retrofit project, under the auspices of the World Bank, is currently under way in Istanbul, Turkey, to address vulnerable school and hospital buildings as discussed in the paper. As part of this effort in Turkey, a guideline that relies on state‐of‐the‐art evaluation and retrofit methods has been developed to assist the local engineers.

Implementation of the program based on the uniform standards developed in the retrofit guidelines, has significantly reduced the seismic risk to schools in Istanbul.

The proposed evaluation and implementation technique can be utilized by governments worldwide to prevent further damage to key infrastructure and save millions of lives.

Innovative retrofits can be used to provide enhanced performance and provide seismic resiliency for cluster of school buildings.

The continual growth of additive manufacturing has increased tremendously because of its versatility, flexibility and high customization of geometric structures. However, design hurdles are presented in understanding the relationship between the fabrication process and materials microstructure as it relates to the mechanical performance. The purpose of this paper is to investigate the role of build architecture and microstructure and the effects of load direction on the static response and mechanical properties of acrylonitrile butadiene styrene (ABS) specimens obtained via the fused deposition modeling (FDM) processing technique.

Among additive manufacturing processes, FDM is a prolific technology for manufacturing ABS. The blend of ABS combines strength, rigidity and toughness, all of which are desirable for the production of structural materials in rapid manufacturing applications. However, reported literature has varied widely on the mechanical performance due to the proprietary nature of the ABS material ratio, ultimately creating a design hurdle. While prior experimental studies have studied the mechanical response via uniaxial tension testing, this study has aimed to understand the mechanical response of ABS from the materials’ microstructural point of view. First, ABS specimen was fabricated via FDM using a defined build architecture. Next, the specimens were mechanically tested until failure. Then finally, the failure structures were microstructurally investigated. In this paper, the effects of microstructural evolution on the static mechanical response of various build architecture of ABS aimed at FDM manufacturing technique was analyzed.

The results show that the rastering orientation of 0/90 exhibited the highest tensile strength followed by fracture at its maximum load. However, the “45” bead direction of the ABS fibers displayed a cold-drawing behavior before rupture. The morphology analyses before and after tensile failure were characterized by a scanning electron microscopy (SEM) which highlighted the effects of bead geometry (layers) and areas of stress concentration such as interstitial voids in the material during build, ultimately compromising the structural integrity of the specimens.

The ability to control the constituents and microstructure of a material during fabrication is significant to improving and predicting the mechanical performance of structural additive manufacturing components. In this report, the effects of microstructure on the mechanical performance of FDM-fabricated ABS materials was discussed. Further investigations are planned in understanding the effects of ambient environmental conditions (such as moisture) on the ABS material pre- and post-fabrication.

The study provides valuable experimental data for the purpose of understanding the inter-dependency between build parameters and microstructure as it relates to the specimens exemplified strength. The results highlighted in this study are fundamental to the development of optimal design of strength and complex ultra-lightweight structure efficiency.

The objective of the study is to examine the response of reinforced concrete (RC) structures subjected to Near-Fault Ground Motions (NFGM) and highlight the importance of considering various factors including the influence of the relative geographical position of near-fault sites that can affect the structural response during an earthquake.

In this paper, the response of a four-storey RC building subjected to NFGMs with varied characteristics like hanging wall and footwall in conjunction with directivity and the effect of pulse-like ground motions with rupture direction are investigated to understand the combined influence of these factors on the behavior of the structure. Furthermore, the capacity and demand of the structural element are investigated for computing the performance ratio.

Results from this study indicate that the most unfavorable combinations for structural damage due to near-fault ground motion are the hanging wall with forward rupture, the fault normal component of ground motions, and pulse-like ground motions with forward directivity.

The results from this study provide valuable insight into the response of RC structures subjected to NFGM and highlight the importance of considering various factors that can affect the structural response during an earthquake. Moreover, the computation of capacity and demand of the critical beam indicates exceedance of desired limits, resulting in the early deterioration of the structural elements. Finally, the analytical analysis from the present study confirms that the hanging wall with forward ruptures, pulse-like motions, and fling steps are the most unfavorable combinations for seismic structural damage.

The aim is to present findings of a theoretical analysis for optimal design of a concrete trough for a new lightweight low‐profile rail track system.

A non‐linear numerical optimisation technique is adopted to predict the minimum area of a pre‐tensioned pre‐stressed trough section satisfying the serviceability and ultimate limit states as per British Standard BS 8110 for critical loading and boundary conditions.

An optimum concrete trough section is calculated to carry all possible load combinations expected during the design life of the track. The performance of the rail, elastomeric pad and track base were found to be satisfactory under the same critical loading and boundary conditions.

The theoretical analysis gives a valuable insight into system parameter values that can optimise design performance and cost. However, these optimal design features now need to be tested experimentally.