Performance assessment of steel structures with semi-rigid joints in seismic areas

2019 ◽  
Vol 11 (1) ◽  
pp. 13-28
Author(s):  
Said Hicham Boukhalkhal ◽  
Abd Nacer Touati Ihaddoudène ◽  
Luis Filipe Da Costa Neves ◽  
Pedro Colmar Gonçalves da Silva Vellasco ◽  
Wafa Madi
Keyword(s):  
Structural Response ◽  
Steel Structures ◽  
Horizontal Displacement ◽  
Dynamical Response ◽  
Seismic Zone ◽  
Joint Flexibility ◽  
Content Type ◽  
Inelastic Behaviour ◽  
Rigid Joints ◽  
The Ideal

Purpose It is well known that the real behaviour of joints lies between the ideal pinned or rigid joint responses. Additionally the influence of this behaviour on the global structural response has been widely studied in the past centred on the plastic resistance or the critical load. On the other hand, there are relatively few studies focusing on the dynamical response of these structures. This paper aims to discuss these issues. Design/methodology/approach Two types of structures with rigid and semi-rigid joints were considered. Their inelastic response was evaluated using the N2 conventional pushover method, and were later compared to the results from a full non-linear dynamic analysis. Findings The results indicated that increasing joint flexibility makes the structure less rigid, lengthening its fundamental period and enhancing its horizontal displacement. Furthermore, a parametric study showed that joint flexibility might be of paramount importance to low to medium rise buildings response. Originality/value The evaluation of the influence of joint flexibility on the inelastic behaviour of steel structures located in seismic zone is of paramount importance, and is tackled in this paper.

Response of multistory steel structure subjected to differential settlements of its foundation

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Adel Hanna ◽  
Wenxue Chen
Keyword(s):  
Environmental Changes ◽  
Structural Response ◽  
Numerical Data ◽  
Steel Structure ◽  
Steel Structures ◽  
Differential Settlement ◽  
Original Research ◽  
Content Type ◽  
Wide Range ◽  
Element Technique

PurposeThis article aims to address an outstanding problem dealing with the structure and its foundation.Design/methodology/approachDifferential settlement between foundation units of a multistory structure has been responsible for serious damage to buildings and often catastrophic failure and loss of life. The dynamic changes in the loading conditions of the structure, and the variability of the underlying ground due to environmental changes, are causing the undesirable differential settlement, which is manifested in the form of additional stresses in beams, columns and distortion of the structure elements. The structural response to the differential settlements depends on the type of the structure (concrete or steel), type of beam-to-column connections (rigid or semi-rigid), number of floors and the spans of the beams in the building. This paper presents the results of a numerical model, which was developed using the finite element technique and the software “ABAQUS” to analyze a nine-floor steel structure. The model was capable to capture the stresses and the strains developed in beams and columns and the relationships of moment–settlement and rotation–settlement for the structural during the differential settlement of its foundation. After validating of the model, data were produced for a wide range of governing parameters for rigid and semi-rigid connections and accordingly the mode of failure. The results can be used as a guideline for the design of steel structures.FindingsResults are useful for those design steel structures.Research limitations/implicationsThis study is based on the experimental and numerical data of the authors.Practical implicationsThis study provides a guideline for the design of steel structures.Originality/valueThis is the original research developed by the authors.

Herbert Olivecrona: founder of Swedish neurosurgery

1993 ◽  
Vol 78 (1) ◽  
pp. 142-149 ◽  
Author(s):  
Bengt Ljunggren
Keyword(s):  
Medical Society ◽  
Practical Application ◽  
Posterior Fossa Tumors ◽  
Neurosurgical Department ◽  
Content Type ◽  
Harvey Cushing ◽  
International Reputation ◽  
Technical Innovations ◽  
Diagnostic Neuroradiology ◽  
The Ideal

✓ Herbert Olivecrona (1891–1980) singlehandedly founded Swedish neurosurgery. At the International Congress in Neurology in Bern in August, 1931, Harvey Cushing invited the cream of the world's medical society to a private banquet. Among the 28 specially invited guests was Herbert Olivecrona. At 40 years old, Olivecrona took his seat with pioneers such as Otfrid Foerster, Percival Bailey, Hugh Cairns, Geoffrey Jefferson, and Sir Charles Sherrington. This suggests that Cushing was impressed by the Swedish aristocrat's didactic deeds when he visited the Serafimer Hospital in Stockholm 2 years earlier. During the mid-1920's, the radiologist Erik Lysholm greatly improved the technique of ventriculography and, challenged by Olivecrona, his diagnostic neuroradiology became of superior quality. In the early 1930's, utilizing technical innovations of his own, Lysholm became a master at demonstrating and localizing posterior fossa tumors, which Olivecrona then operated on. Olivecrona's clinic became the mecca to which many scholars, thirsting for more knowledge, went on a pilgrimage. The international reputation of the clinic was founded, not on epoch-making discoveries, but by the resolute and practical application of methods already launched elsewhere and the exemplary organization that Olivecrona had established in collaboration with Lysholm. In spite of hardships and primitive working conditions, the clinic at the Serafimer Hospital gradually developed into the ideal prototype for a modern neurosurgical department. Olivecrona trained many colorful personalities who later were to lay the foundation for neurosurgery in their home countries; these included Wilhelm Tönnis of Germany, Edvard Busch of Denmark, and Aarno Snellman of Finland. Olivecrona was a true pioneer who made major contributions in practically all fields of conventional neurosurgery.

Managerial identity development across the age-spectrum from an ideal self and values perspective

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Udayan Dhar
Keyword(s):  
Identity Development ◽  
Professional Identity ◽  
Personal Values ◽  
Ideal Self ◽  
Professional Identity Development ◽  
Content Type ◽  
Management Professionals ◽  
Inductive Thematic Analysis ◽  
The Ideal

PurposeThe purpose of this study is to investigate professional identity development among management professionals through the lens of the ideal self and personal values.Design/methodology/approachDetailed career vision essays based on the ideal self and personal values of 48 participants ranging in age from 22 to 54 were analyzed using an inductive thematic analysis. A theory-based classification of their personal values, collected through a survey, was also conducted as a supplemental analysis.FindingsThe visions of older management professionals were less career-oriented, more holistic, involved in a greater multiplicity of career roles, had more clarity and placed higher emphasis on work–life balance and on developing others. The older participants also reported having fewer self-enhancement values.Originality/valueThe findings demonstrate the relevance of the ideal self as a lens to study identity development and advance our understanding of professional identity development in the context of modern careers.

scholarly journals Gendering expert work and ideal candidacy in Finnish and Estonian job advertisements

2018 ◽  
Vol 33 (7) ◽  
pp. 544-560 ◽  
Author(s):  
Jatta Jännäri ◽  
Seppo Poutanen ◽  
Anne Kovalainen
Keyword(s):  
Design Methodology ◽  
Doing Gender ◽  
Content Type ◽  
Market Structures ◽  
Job Advertisements ◽  
Management Literature ◽  
Global Construction ◽  
Managerial Positions ◽  
Definition Of ◽  
The Ideal

Purpose This paper aims to analyse the ways the textual materials of job advertisements do the gendering for prospective expert positions and create a space for ambiquity/non-ambiquity in the gender labelling of this expertise. Expert positions are almost always openly announced and are important to organizations because they often lead to higher managerial positions. By gendering the prospective positions, the job advertisements bring forth repertoires strengthening the gendering of work and gendered expert employee positions. Design/methodology/approach This study draws on qualitative textual and visual data of open job advertisements for expert positions. The materials of the study are gathered from open job advertisements in two countries, i.e. Finland and Estonia with rather similar labour market structures in relation to gender positions but differing as regards their gender equality. Findings The analyses show that the gendering of expert work takes place in the job advertisements by rendering subtly gendered articulations, yet allowing for interpretative repertoires appear. The analysis reveals some differences in the formulations of the advertisements for expert jobs in the two countries. It also shows that in general the requirements for an ideal expert candidate are coated with superlatives that are gendered in rather stereotypical ways, and that the ideal candidates for highly expert jobs are extremely flexible and follows the ideal of an adaptable and plastic employee, willing to work their utmost. This paper contributes to the “doing gender” literature by adding an analysis of the textual gendering of ideal candidates for positions of expertise. Research limitations/implications The research materials do not expose all the issues pertinent to questions of the ideal gendered candidate. For instance, questions of ethnicity in relation to the definition of the ideal candidate cannot be studied with the data used for this study. Being an exploratory study, the results do not aim for generalizable results concerning job advertisements for expert positions. Originality/value This paper contributes to the “doing gender” and “gendering” literature by addressing the question of how and in what ways gender is defined and done for an expert positions prior the candidates are chosen to those jobs. It also offers new insights into the global construction of gendered expert jobs advertisements by addressing the topic with data from two countries. It further contributes to understanding the gendered shaping of expertise in the management literature.

Design optimisation for cold-formed steel residential roof truss using genetic algorithm

2018 ◽  
Vol 15 (5) ◽  
pp. 575-583
Author(s):  
Ka Yee Kok ◽  
Hieng Ho Lau ◽  
Thanh Duoc Phan ◽  
TIina Chui Huon Ting
Keyword(s):  
Genetic Algorithm ◽  
Industrial Application ◽  
Steel Structures ◽  
Single Type ◽  
Efficient Design ◽  
Design Optimisation ◽  
Content Type ◽  
Roof Truss ◽  
Cold Formed Steel ◽  
Multi Level

Purpose This paper aims to present the design optimisation using genetic algorithm (GA) to achieve the highest strength to weight (S/W) ratio, for cold-formed steel residential roof truss. Design/methodology/approach The GA developed in this research simultaneously optimises roof pitch, truss configurations, joint coordinates and applied loading of typical dual-pitched symmetrical residential roof truss. The residential roof truss was considered with incremental uniform distributed loading, in both gravitational and uplift directions. The structural analyses of trusses were executed in this GA using finite element toolbox. The ultimate strength and serviceability of trusses were checked through the design formulation implemented in GA, according to the Australian standard, AS/NZS 4600 Cold-formed Steel Structures. Findings An optimum double-Fink roof truss which possess highest S/W ratio using GA was determined, with optimum roof pitch of 15°. The optimised roof truss is suitable for industrial application with its higher S/W ratio and cost-effectiveness. The combined methodology of multi-level optimisation and simultaneous optimisation developed in this research could determine optimum roof truss with consistent S/W ratio, although with huge GA search space. Research limitations/implications The sizing of roof truss member is not optimised in this paper. Only single type of cold-formed steel section is used throughout the whole optimisation. The design of truss connection is not considered in this paper. The corresponding connection costs are not included in the proposed optimisation. Practical implications The optimum roof truss presented in this paper is suitable for industrial application with higher S/W ratio and lower cost, in either gravitational or uplift loading configurations. Originality/value This research demonstrates the approaches in combining multi-level optimisation and simultaneous optimisation to handle large number of variables and hence executed an efficient design optimisation. The GA designed in this research determines the optimum residential roof truss with highest S/W ratio, instead of lightest truss weight in previous studies.

A multi-scenario assessment of the seismogenic tsunami hazard for Bangladesh

2019 ◽  
Vol 11 (2) ◽  
pp. 156-168
Author(s):  
Janaka J. Wijetunge
Keyword(s):  
Subduction Zones ◽  
Submarine Canyon ◽  
Tsunami Hazard ◽  
Seismic Zone ◽  
Tsunami Propagation ◽  
Content Type ◽  
Arrival Times ◽  
Tsunami Waves ◽  
Scenario Assessment ◽  
Seismic Scenarios

Purpose This paper aims to describe a multi-scenario assessment of the seismogenic tsunami hazard for Bangladesh from active subduction zones in the Indian Ocean region. Two segments of the Sunda arc, namely, Andaman and Arakan, appear to pose a tsunamigenic seismic threat to Bangladesh. Design/methodology/approach High-resolution numerical simulations of tsunami propagation toward the coast of Bangladesh have been carried out for eight plausible seismic scenarios in Andaman and Arakan subduction zones. The numerical results have been analyzed to obtain the spatial variation of the maximum tsunami amplitudes as well as tsunami arrival times for the entire coastline of Bangladesh. Findings The results suggest that the tsunami heights are amplified on either side of the axis of the submarine canyon which approaches the nearshore sea off Barisal in the seaboard off Sundarban–Barisal–Sandwip. Moreover, the computed tsunami amplitudes are comparatively higher north of the latitude 21.5o in the Teknaf–Chittagong coastline. The calculated arrival times indicate that the tsunami waves reach the western half of the Sundarban–Barisal–Sandwip coastline sooner, while shallow water off the eastern half results in a longer arrival time for that part of the coastline, in the event of an earthquake in the Andaman seismic zone. On the other hand, most parts of the Chittagong–Teknaf coastline would receive tsunami waves almost immediately after an earthquake in the northern segment of the Arakan seismic zone. Originality/value The present assessment includes probabilistic measures of the tsunami hazard by incorporating several probable seismic scenarios corresponding to recurrence intervals ranging from 25 years to over 1,000 years.

scholarly journals The effect of seismic base isolation on structural response of a 12-story hotel building in Padang, Indonesia

2020 ◽  
Vol 156 ◽  
pp. 05026
Author(s):  
Fauzan ◽  
Afdhalul Ihsan ◽  
Mutia Putri Monika ◽  
Zev Al Jauhari
Keyword(s):  
Base Isolation ◽  
Response Spectrum ◽  
Soft Soil ◽  
Structural Response ◽  
Time History ◽  
Seismic Zone ◽  
Isolation System ◽  
Rubber Bearing ◽  
Seismic Base Isolation ◽  
The City

The amount of potential investment in Padang City, Indonesia since 2017 attracted many investors to contribute to the city. One of the investments is a 12-story hotel that will be constructed in By Pass Street of the city. The hotel is located in a high seismic zone area, so the seismic base isolation has been proposed to be used in the hotel building. The main aim of using a seismic base isolation device is to reduce the inertia forces introduced in the structure due to earthquakes by shifting the fundamental period of the structure out of dangerous resonance range and concentration of the deformation demand at the isolation system. An analytical study on the Reinforced Concrete (RC) hotel building with and without rubber bearing (RB) base isolation is carried out using the response spectrum and time history analysis methods. The results show that internal forces and inter-story drift of the building with high damping rubber bearing (HDRB) are lower than that of the fixed base with a remarkable margin. From this study, it is recommended to use the HDRB base isolation for medium and high rise buildings with soft soil in Padang City, Indonesia.

scholarly journals Dynamic Analysis on RCC and Composite Structure for Uniform and Optimized Section

2021 ◽  
Vol 9 (12) ◽  
pp. 1114-1127
Author(s):  
Ankit Kumar
Keyword(s):  
Dynamic Analysis ◽  
Composite Structure ◽  
Composite Structures ◽  
Response Spectrum ◽  
Steel Structures ◽  
Seismic Zone ◽  
Dead Weight ◽  
Conventional Concrete ◽  
High Rise ◽  
Time Period

Abstract: This study examines the composite structure that is increasing commonly in developing countries. For medium-rise to high-rise building construction, RCC structures is no longer economical due to heavy dead weight, limited span, low natural frequency and hazardous formwork. The majority of commercial buildings are designed and constructed with reinforced concrete, which largely depends on the existence of the constituent materials as well as the quality of the necessary construction skills, and including the usefulness of design standards. Conventional RCC structure is not preferred nowadays for high rise structure. However, composite construction, is a recent development in the construction industry. Concrete-steel composite structures are now very popular due to some outstanding advantages over conventional concrete and steel structures. In the present work, RCC and steel-concrete composite structure are being considered for a Dynamic analysis of a G+25-storey commercial building of uniform and optimized section, located at in seismic zone IV. Response Spectrum analysis method is used to analyze RCC and composite structure, CSI ETABS v19 software is used and various results are compared such as time period, maximum storey displacement, maximum storey stiffness. Maximum storey shear and maximum stoey overturning moment. Keywords: RCC Structure, Composite Structure, Uniform Section, Optimized Section, Shear Connector, Time Period, Storey Displacement, Storey Shear, Storey Stiffness, Response Spectrum method, ETABS

Vibration of Box-Type Structures with Flexible Joints between Constituent Plates

1968 ◽  
Vol 10 (3) ◽  
pp. 294-298 ◽  
Author(s):  
S. M. Dickinson
Keyword(s):  
Analytical Method ◽  
Natural Frequencies ◽  
Mode Shapes ◽  
Flexible Joints ◽  
Joint Flexibility ◽  
Rigid Joints

In a recent paper by Dickinson and Warburton (1), an analytical method of determining natural frequencies and mode shapes of box-type structures having rigid joints between constituent plates was given. Practical box-type structures may well include joints having some flexibility, and it is the purpose of this Note to indicate how the earlier analysis can be modified to apply to such structures and to show the effect of joint flexibility on the natural frequencies of a particular structure.

Measuring higher education performance in Brazil: government indicators of performance vs ideal solution efficiency measures

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Peter F. Wanke ◽  
Jorge J.J. Antunes ◽  
Vitor Y. Miano ◽  
Cassio L.P. do Couto ◽  
Franklin G. Mixon
Keyword(s):  
Covariance Matrix ◽  
Educational Institution ◽  
Strong Relationship ◽  
Ideal Solution ◽  
Content Type ◽  
Federal Institute ◽  
Efficiency Measures ◽  
Solution Efficiency ◽  
Education Performance ◽  
The Ideal

PurposeThis study extends the educational institutions' performance and efficiency literature by examining Brazil's Federal Institute of Education, Science and Technology (FIEST), which consists of educational units throughout the country that span several levels of education.Design/methodology/approachThe authors build and analyze a covariance matrix consisting of both a group of efficiency measures and a group of performance indicators used by Brazil's Ministry of Education (BME). The values in the covariance matrix are maximized through application of the Technique for Order of Preference by Similarity to the Ideal Solution (TOPSIS), in which the weights of each variable are optimized in order to capture the direction of the relationship between the two sets of efficiency measures.FindingsAlthough the authors find that the collective efficiency of the educational units analyzed did not change during the period of study, the analysis reveals that government indicators of performance do not exhibit a strong relationship to the ideal solution efficiency measures used in this study.Originality/valueThis study extends the educational institution efficiency literature by examining Brazil's FIEST, which consists of 40 educational units throughout the country that spans several levels of education, from upper high school vocational courses to higher degrees.

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