Upgrading Seismic Behaviors of R/C Frames with Shaped Memory Alloys Based Braces

2020 ◽  
Vol 3 (2) ◽  
pp. 993-1002
Author(s):  
Ali Reza Allahverdizade ◽  
Serenay Kara ◽  
Savaş Erdem
Keyword(s):  
Earthquake Engineering ◽  
Smart Materials ◽  
Intelligent Systems ◽  
Structural Engineering ◽  
New Technologies ◽  
Time History ◽  
Damping Capacity ◽  
Base Shear ◽  
Permanent Displacement ◽  
Structural Fatigue

Intelligent systems in structural engineering are systems that are capable of automatically adapting structural behavior in response to instantaneous loads, thereby ensuring the safety of extended structural life and performance. One of the new technologies that makes it possible to achieve these goals is the production and development of smart materials. Examples of these smart materials used in structural engineering include piezo-ceramics, magnetorheological fluids, electrorheological fluids, and form-memory alloys. Shaped Memory Alloys (SMAs) are new materials that have been used in various fields of science and engineering in recent decades. In recent years, these materials attracted the attention of researchers in the field of building and earthquake engineering due to their properties such as high damping capacity, low permanent displacement and structural fatigue resistance. One of the application areas of these materials is that they are used as a brace in the structures, so the research results have shown the acceptable performance and operability of such structural systems. In this study, shape memory bracelets and steel bracelets installed as structural brackets were used as a lateral load system in the seismic improvement of concrete bending frames and factors such as residual displacement and base shear in these two load-bearing systems are compared.  The model under studying is a 6-story frame that has been subjected to time history analysis. SeismoStruct software was used to analyze the model.

Ambient Assisted Living Systems: The Scope of Research and Development

2017 ◽  
Vol 3 (2) ◽  
pp. 21
Author(s):  
Ashish D Patel ◽  
Jigarkumar H. Shah
Keyword(s):  
Assisted Living ◽  
Independent Living ◽  
Intelligent Systems ◽  
New Technologies ◽  
Ambient Assisted Living ◽  
Smart Devices ◽  
Economic Changes ◽  
Aged Population ◽  
The People ◽  
Living Person

The aged population of the world is increasing by a large factor due to the availability of medical and other facilities. As the number grows rapidly, requirements of this segment of age (65+) are increasing rapidly as well as the percentage of aged persons living alone is also increasing with the same rate due to the inevitable socio-economic changes. This situation demands the solution of many problems like loneliness, chronic conditions, social interaction, transportation, day-to-day life and many more for independent living person. A large part of aged population may not be able to interact directly with new technologies. This sought some serious development towards the use of intelligent systems i.e. smart devices which helps the people with their inability to use the available as well future solutions. Ambient Assisted Living (AAL) is the answer to these problems. In this paper, issues related to AAL systems are studied. Study of challenges and limitations of this comparatively new field will help the designers to remove the barriers of AAL systems.

POTENTIAL OF INTRODUCING DIGITAL AND INTELLIGENT SYSTEMS IN ELECTRICITY

2020 ◽  
Vol 37 (3) ◽  
pp. 36-45
Author(s):  
F.F. Khabirov ◽  
V.S. Vokhmin ◽  
Keyword(s):  
Distributed Generation ◽  
Energy Supply ◽  
Intelligent Systems ◽  
New Technologies ◽  
Technological Development ◽  
Energy Systems ◽  
Electric Power Industry ◽  
Energy Sector ◽  
Current Level ◽  
Environmental Friendliness

The article considers the possibility of introducing digital and intelligent systems in the electric power industry, including the analysis of the consequences after the introduction of new technologies on the economic, social and technological side. Currently, the concept of distributed generation is being used more and more often in the global energy arena. This is certainly a trend in the energy sector. The current level of technological development in the energy sector is quite high, but in order to continue to increase competitiveness, we need a further transition to digital and intelligent energy systems that will increase the reliability, quality, environmental friendliness and automation of energy supply.

scholarly journals Comparison of Novel Seismic Protection Devices to Attenuate the Earthquake Induced Energy

Actuators ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 73
Author(s):  
Osman Hansu ◽  
Esra Mete Güneyisi
Keyword(s):  
Lateral Displacement ◽  
Time History ◽  
Seismic Protection ◽  
Base Shear ◽  
Seismic Demands ◽  
Nonlinear Time History Analyses ◽  
History Of ◽  
Protection Devices ◽  
Nonlinear Time History ◽  
Better Than

This study addresses an alternative use of viscous dampers (VDs) associated with buckling restrained braces (BRBs) as innovative seismic protection devices. For this purpose, 4-, 8- and 12-story steel bare frames were designed with 6.5 m equal span length and 4 m story height. Thereafter, they were seismically improved by mounting the VDs and BRBs in three patterns, namely outer bays, inner bays, and all bays over the frame heights. The structures were modeled using SAP 2000 software and evaluated by the nonlinear time history analyses subjected to the six natural ground motions. The seismic responses of the structures were investigated for the lateral displacement, interstory drift, absolute acceleration, maximum base shear, and time history of roof displacement. The results clearly indicated that the VDs and BRBs reduced seismic demands significantly compared to the bare frame. Moreover, the all-bay pattern performed better than the others.

scholarly journals Exceedance of design actions in epicentral areas: insights from the ShakeMap envelopes for the 2016–2017 central Italy sequence

2021 ◽  
Author(s):  
Iunio Iervolino ◽  
Pasquale Cito ◽  
Chiara Felicetta ◽  
Giovanni Lanzano ◽  
Antonio Vitale
Keyword(s):  
Earthquake Engineering ◽  
Structural Damage ◽  
Structural Engineering ◽  
Central Italy ◽  
Civil Defense ◽  
Point Of View ◽  
Seismic Sequence ◽  
Ground Shaking ◽  
Motion Effect ◽  
Observed Damage

AbstractShakeMap is the tool to evaluate the ground motion effect of earthquakes in vast areas. It is useful to delimit the zones where the shaking is expected to have been most significant, for civil defense rapid response. From the earthquake engineering point of view, it can be used to infer the seismic actions on the built environment to calibrate vulnerability models or to define the reconstruction policies based on observed damage vs shaking. In the case of long-lasting seismic sequences, it can be useful to develop ShakeMap envelopes, that is, maps of the largest ground intensity among those from the ShakeMap of (selected) events of a seismic sequence, to delimit areas where the effects of the whole sequence have been of structural engineering relevance. This study introduces ShakeMap envelopes and discusses them for the central Italy 2016–2017 seismic sequence. The specific goals of the study are: (i) to compare the envelopes and the ShakeMap of the main events of the sequence to make the case for sequence-based maps; (ii) to quantify the exceedance of design seismic actions based on the envelopes; (iii) to make envelopes available for further studies and the reconstruction planning; (iv) to gather insights on the (repeated) exceedance of design seismic actions at some sites. Results, which include considerations of uncertainty in ShakeMap, show that the sequence caused exceedance of design hazard in thousands of square kilometers. The most relevant effects of the sequence are, as expected, due to the mainshock, yet seismic actions larger than those enforced by the code for structural design are found also around the epicenters of the smaller magnitude events. At some locations, the succession of ground-shaking that has excited structures, provides insights on structural damage accumulation that has likely taken place; something that is not accounted for explicitly in modern seismic design. The envelopes developed are available as supplemental material.

scholarly journals Tuned Mass Damper Design for Slender Masonry Structures: A Framework for Linear and Nonlinear Analysis

2021 ◽  
Vol 11 (8) ◽  
pp. 3425
Author(s):  
Marco Zucca ◽  
Nicola Longarini ◽  
Marco Simoncelli ◽  
Aly Mousaad Aly
Keyword(s):  
Nonlinear Analysis ◽  
Linear Time ◽  
Design Procedure ◽  
Time History ◽  
Tuned Mass Damper ◽  
Second Phase ◽  
Masonry Structures ◽  
Base Shear ◽  
Mass Damper ◽  
Linear And Nonlinear

The paper presents a proposed framework to optimize the tuned mass damper (TMD) design, useful for seismic improvement of slender masonry structures. A historical masonry chimney located in northern Italy was considered to illustrate the proposed TMD design procedure and to evaluate the seismic performance of the system. The optimization process was subdivided into two fundamental phases. In the first phase, the main TMD parameters were defined starting from the dynamic behavior of the chimney by finite element modeling (FEM). A series of linear time-history analyses were carried out to point out the structural improvements in terms of top displacement, base shear, and bending moment. In the second phase, masonry's nonlinear behavior was considered, and a fiber model of the chimney was implemented. Pushover analyses were performed to obtain the capacity curve of the structure and to evaluate the performance of the TMD. The results of the linear and nonlinear analysis reveal the effectiveness of the proposed TMD design procedure for slender masonry structures.

The Multi-Relationship Evaluation Design Framework: Designing Testing Plans to Comprehensively Assess Advanced and Intelligent Technologies

2010 ◽  
Author(s):  
Brian A. Weiss ◽  
Linda C. Schmidt ◽  
Harry A. Scott ◽  
Craig I. Schlenoff
Keyword(s):  
Intelligent Systems ◽  
New Technologies ◽  
Evaluation Framework ◽  
Evaluation Design ◽  
Design Elements ◽  
Summative Assessments ◽  
Extensive Evaluation ◽  
Level Of Knowledge ◽  
Definition Of ◽  
Key Terms

As new technologies develop and mature, it becomes critical to provide both formative and summative assessments on their performance. Performance assessment events range in form from a few simple tests of key elements of the technology to highly complex and extensive evaluation exercises targeting specific levels and capabilities of the system under scrutiny. Typically the more advanced the system, the more often performance evaluations are warranted, and the more complex the evaluation planning becomes. Numerous evaluation frameworks have been developed to generate evaluation designs intent on characterizing the performance of intelligent systems. Many of these frameworks enable the design of extensive evaluations, but each has its own focused objectives within an inherent set of known boundaries. This paper introduces the Multi-Relationship Evaluation Design (MRED) framework whose ultimate goal is to automatically generate an evaluation design based upon multiple inputs. The MRED framework takes input goal data and outputs an evaluation blueprint complete with specific evaluation elements including level of technology to be tested, metric type, user type, and, evaluation environment. Some of MRED’s unique features are that it characterizes these relationships and manages their uncertainties along with those associated with evaluation input. The authors will introduce MRED by first presenting relationships between four main evaluation design elements. These evaluation elements are defined and the relationships between them are established including the connections between evaluation personnel (not just the users), their level of knowledge, and decision-making authority. This will be further supported through the definition of key terms. An example will be presented in which these terms and relationships are applied to the evaluation design of an automobile technology. An initial validation step follows where MRED is applied to the speech translation technology whose evaluation design was inspired by the successful use of a pre-existing evaluation framework. It is important to note that MRED is still in its early stages of development where this paper presents numerous MRED outputs. Future publications will present the remaining outputs, the uncertain inputs, and MRED’s implementation steps that produce the detailed evaluation blueprints.

scholarly journals Implementation of the structural performance factor (Sp) within a displacement-based design framework

2018 ◽  
Vol 51 (3) ◽  
pp. 159-165 ◽  
Author(s):  
Dion Marriott
Keyword(s):  
Response Spectrum ◽  
Time History ◽  
Structural Performance ◽  
Integration Time ◽  
Design Framework ◽  
Base Shear ◽  
Structural Behaviour ◽  
Performance Factor ◽  
Design Response Spectrum ◽  
Displacement Based

This paper discusses the application of the Structural Performance factor (SP) within a Direct Displacement-Based Design framework (Direct-DBD). As stated within the New Zealand loadings standard, NZS1170.5:2004 [1], the SP factor is a base shear multiplier (reduction factor) for ductile structures, i.e. as the design ductility increases, the SP factor reduces. The SP factor is intended to acknowledge the better-than-expected structural behaviour of ductile systems (both strength, and ductility capacity) by accounting for attributes of response that designers are unable to reliably estimate. The SP factor also recognizes the less dependable seismic performance of non-ductile structures, by permitting less of a reduction (a larger SP factor) for non-ductile structures. Within a traditional force-based design framework the SP factor can be applied to either the design response spectrum (a seismic hazard/demand multiplier), or as a base shear multiplier at the end of design (structural capacity multiplier) – either of these two approaches will yield an identical design in terms of the required design base shear and computed ULS displacement/drift demands. However, these two approaches yield very different outcomes within a Direct-DBD framework – in particular, if SP is applied to the seismic demand, the design base shear is effectively multiplied by (SP)2 (i.e. a two-fold reduction). This paper presents a “DBD-corrected” SP factor to be applied to the design response spectrum in Direct-DBD in order to achieve the intent of the SP factor as it applies to force-based design. The proposed DBD-corrected SP factor is attractive in that it is identical to the SP relationship applied to the elastic site hazard spectrum C(T) for numerical integration time history method of analysis within NZS 1170.5:2004 [1], SP,DDBD = (1+SP)/2.

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