scholarly journals Tension-only ideal dissipative bracing for the seismic retrofit of precast industrial buildings

2021 ◽  
Author(s):  
Bruno Dal Lago ◽  
Muhammad Naveed ◽  
Marco Lamperti Tornaghi
Keyword(s):  
Performance Indicator ◽  
Seismic Retrofit ◽  
Seismic Retrofitting ◽  
Structural Behaviour ◽  
Load Range ◽  
Main Challenge ◽  
Highly Nonlinear ◽  
Earthquake Load ◽  
Definition Of ◽  
Nonlinear Dynamic Analyses

AbstractNew precast frame industrial structures are seismically designed according to reliable modern criteria. However, most of the existing built stock hosting many workers and both regular and strategic industrial activities was designed and detailed neglecting the earthquake load or according to outdated seismic design criteria and regulations. Its seismic retrofit is a main challenge for the Engineering Community and a critical objective for institutional and private bodies. Among the envisaged solutions, the introduction of dissipative braces appears to be promising, although mostly inapplicable for these buildings, due to the brace lengths required by their typical large dimensions and the related proportioning against buckling. In this paper, an innovative seismic retrofitting technique based on monolateral dissipative bracing is investigated. The device proposed in this paper, yet in phase of preliminary design and testing, dissipates energy through friction in tension only while freely deforming in compression, which makes the issue related to compressive buckling irrelevant. A numerical analysis is carried out to investigate the efficiency of the proposed device in seismic retrofitting of precast industrial frame buildings with the aim to explore its feasibility and to better orient the definition of the slip threshold load range and the future development of the physical device. The simplified Capacity Spectrum Method (CSM) is employed for the global framing of the structural behaviour of the highly nonlinear retrofitted structures under seismic actions. A numerical tool is set to automatically apply the CSM based on the definition of few main parameters governing the seismic response of precast frame structures. The efficacy of the CSM is critically analysed through the comparison with the results of a set of nonlinear dynamic analyses. A smart simplified design process aimed at framing the most efficient threshold slip/yield load of the device given an existing structural configuration is presented with the application of the CSM through the identification of the most efficient performance indicator related to either displacement, shear force, equivalent dissipation of energy or a combination of them.

scholarly journals Interpersonal nurse-patient relationship with a young schizophrenic pregnant woman

2016 ◽  
Vol 10 (2) ◽  
pp. 136-148
Author(s):  
Renata Marques de Oliveira ◽  
Antonia Regina Ferreira Furegato
Keyword(s):  
Thematic Analysis ◽  
Psychiatric Treatment ◽  
Interpersonal Relationship ◽  
Psychiatric History ◽  
Patient Relationship ◽  
Therapeutic Interaction ◽  
Main Challenge ◽  
Schizophrenic Woman ◽  
Definition Of ◽  
Insight Into

The objective of this study was to investigate elements of the personal and psychiatric history, as well as the challenges related to motherhood, of a young schizophrenic female, through person-centered therapeutic interaction. The investigation had an exploratory scope, undertaken in a teaching hospital and data were collected during nondirective interaction on the part of the nurse with a young schizophrenic woman who had been treated in the institution for 10 years. Thematic analysis of the content was undertaken, with emphasis on the nuclei of meaning, identification of the themes and definition of the categories. The patient, called L. in this study, was 30 years old, had a two-year-old child and was three months pregnant when data were collected. Her trajectory was characterized by doubts, fears and uncertainties. The episodes of hospitalization, the coexistence with other patients, and the medications promoted insight into the symptoms, and acceptance of the diagnosis. The main challenge was experiencing pregnancy and the puerperium concomitantly with the psychiatric treatment. The interpersonal relationship established evidenced that, the young woman felling understood and that her needs were attended, overcame several difficulties she had reported and felt fulfilled and integrated into her social environment.

scholarly journals A spatial connectivity approach to landscapes of conflict: Julius Caesar and the assault to Puig Ciutat (NE Iberian Peninsula)

2021 ◽  
Author(s):  
Xavier Rubio-Campillo ◽  
Eduard Ble ◽  
Àngels Pujol ◽  
Roger Sala ◽  
Robert Tamba
Keyword(s):  
Iberian Peninsula ◽  
Vital Role ◽  
Statistical Hypothesis ◽  
Julius Caesar ◽  
Mobility Patterns ◽  
Least Cost Path ◽  
Statistical Hypothesis Testing ◽  
Main Challenge ◽  
Definition Of ◽  
Ne Iberian Peninsula

Landscape plays a vital role in the development of military campaigns through the definition of geostrategic landmarks that structure the control of the territory, the imposition of constraints to the movement of armies, and the identification of positions that facilitate defensive tactics against aggressors. These factors are linked to the study of past spatial mobility which is typically performed using Least-Cost Path analysis (LCP). LCP identifies the optimal route that connects any two given points based on minimizing the accumulated cost based on a friction surface map, thus allowing archaeologists to identify the most efficient pathways across a territory. The main challenge of LCP analysis for archaeological regions is that optimal pathways are not well suited to define general mobility patterns within highly uncertain scenarios. Connectivity modelling based on Circuit Theory (CT) is an alternative approach to the study of mobility. CT does not generate a single path like LCP does; it captures the connectivity of an entire region identifying not only optimal paths, but also bottlenecks, dead-ends and any other spatial feature that may impact movement.We present here a framework to study landscapes of conflict using connectivity modelling; the framework combines CT, visibility analysis and statistical hypothesis testing to understand the reasons behind the assault and destruction of Puig Ciutat (NE Iberian Peninsula) during Julius Caesar's civil war. Results suggest that the site exerted decisive control over a highly connected area linking two possible logistical bases (Emporion and Massalia) to the armies fighting at Ilerda (49 BC).

scholarly journals Benchmarking of bank performance using the life cycle concept and the DEA approach

2017 ◽  
Vol 12 (3) ◽  
pp. 74-86 ◽  
Author(s):  
Volodymyr Ponomarenko ◽  
Oleh Kolodiziev ◽  
Iryna Chmutova
Keyword(s):  
Life Cycle ◽  
Business Processes ◽  
Performance Indicator ◽  
Bank Performance ◽  
Customer Base ◽  
Target Values ◽  
Comparable Performance ◽  
Dea Method ◽  
Dea Approach ◽  
Definition Of

Despite the widespread use of benchmarking as an effective tool for improving the efficiency of the bank’s functioning, its implementation does not take into account the relation between comparable performance indicators, the choice of benchmark for comparison, deviations of indicators from target values with stages of the bank’s life cycle, which cause differences in the intensity and characteristics of development of financial institutions. The procedure for identifying a reference bank for comparison is also insufficiently specified, which is important in terms of adapting its experience by the recipient bank due to the possible fundamental differences in their functioning. Therefore, the article has modified the technology of benchmarking of the bank’s performance based on the life cycle concept and the DEA approach. The research is based on the use of the DEA method to determine the most efficient bank as a reference bank in benchmarking comparison; canonical analysis – for the formation of a list of indicators of bank performance; cluster analysis – to substantiate the levels of deviations of the actual values of comparable indicators from the target ones. The study envisages, firstly, the selection of indicators for benchmarking comparisons based on the identification of causal relationships between the indicators of subsystems “Finance”, “Customers”, “Business processes”, “Personnel development” that arise at each stage of a bank’s life cycle; secondly, the choice of a benchmark bank for comparison according to the maximum value of the performance indicator calculated through the DEA method for a set of banks that are at one and the same stage of their life cycle; thirdly, definition of the range of deviations (low, permissible, critical) of the actual values of comparable indicators of the effectiveness of management of finance, customer base, business processes and personnel of the bank from the target ones. A practical testing of the benchmarking technology was carried out on the example of Ukrainian banks, whose stage in 2016 was identified as “intense growth”.

scholarly journals Revisiting Classical Issues of Fatigue Crack Growth Using a Non-Linear Approach

Materials ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 5544
Author(s):  
Micael F. Borges ◽  
Diogo M. Neto ◽  
Fernando V. Antunes
Keyword(s):  
Plastic Deformation ◽  
Fatigue Crack ◽  
Fatigue Crack Growth ◽  
Crack Growth ◽  
Crack Closure ◽  
Crack Tip ◽  
Maximum Load ◽  
Numerical Approach ◽  
Load Range ◽  
Definition Of

Fatigue crack growth (FCG) has been studied for decades; however, several aspects are still objects of controversy. The objective here is to discuss different issues, using a numerical approach based on crack tip plastic strain, assuming that FCG is driven by crack tip deformation. ΔK was found to control cyclic plastic deformation at the crack tip, while Kmax has no effect. Therefore, alternative mechanisms are required to justify models based on ΔK and Kmax. The analysis of crack tip plastic deformation also showed that there is crack tip damage below crack closure. Therefore, the definition of an effective load range ΔKeff = Kmax − Kopen is not correct, because the portion of load range below opening also contributes to FCG. Below crack closure, damage occurs during unloading while during loading the crack tip deformation is elastic. However, if the maximum load is decreased below the elastic limit, which corresponds to the transition between elastic and elasto–plastic regimes, there is no crack tip damage. Additionally, a significant effect of the crack ligament on crack closure was found in tests with different crack lengths and the same ΔK. Finally, the analysis of FCG after an overload with and without contact of crack flanks showed that the typical variation of da/dN observed is linked to crack closure variations, while the residual stresses ahead of crack tip are not affected by the contact of crack flanks.

scholarly journals Analytical investigation of a three-dimensional FRP-retrofitted reinforced concrete structure's behaviour under earthquake load effect in ANSYS program

2012 ◽  
Vol 12 (12) ◽  
pp. 3701-3707 ◽  
Author(s):  
F. Altun ◽  
F. Birdal
Keyword(s):  
Reinforced Concrete ◽  
Analytical Data ◽  
Three Dimensional ◽  
Analytical Investigation ◽  
Crack Development ◽  
Model Structure ◽  
Structural Behaviour ◽  
Load Effect ◽  
Laboratory Setup ◽  
Earthquake Load

Abstract. In this study, a 1:3 scaled, three-storey, FRP (Fiber Reinforced Polymer) retrofitted reinforced concrete model structure whose behaviour and crack development were identified experimentally in the laboratory was investigated analytically. Determination of structural behaviour under earthquake load is only possible in a laboratory environment with a specific scale, as carrying out structural experiments is difficult due to the evaluation of increased parameter numbers and because it requires an expensive laboratory setup. In an analytical study, structure was modelled using ANSYS Finite Element Package Program (2007), and its behaviour and crack development were revealed. When experimental difficulties are taken into consideration, analytical investigation of structure behaviour is more economic and much faster. At the end of the study, experimental results of structural behaviour and crack development were compared with analytical data. It was concluded that in a model structure retrofitted with FRP, the behaviour and cracking model can be determined without testing by determining the reasons for the points where analytical results are not converged with experimental data. Better understanding of structural behaviour is analytically enabled with the study.

scholarly journals Helmholtz’s decomposition for compressible flows and its application to computational aeroacoustics

2020 ◽  
Vol 1 (6) ◽  
Author(s):  
Stefan Schoder ◽  
Klaus Roppert ◽  
Manfred Kaltenbacher
Keyword(s):  
Flow Velocity ◽  
Compressible Flows ◽  
Base Flow ◽  
Computational Aeroacoustics ◽  
Helmholtz Decomposition ◽  
The Finite Element Method ◽  
Main Challenge ◽  
Source Data ◽  
Flow Domain ◽  
Definition Of

Abstract The Helmholtz decomposition, a fundamental theorem in vector analysis, separates a given vector field into an irrotational (longitudinal, compressible) and a solenoidal (transverse, vortical) part. The main challenge of this decomposition is the restricted and finite flow domain without vanishing flow velocity at the boundaries. To achieve a unique and $$L_2$$ L 2 -orthogonal decomposition, we enforce the correct boundary conditions and provide its physical interpretation. Based on this formulation for bounded domains, the flow velocity is decomposed. Combining the results with Goldstein’s aeroacoustic theory, we model the non-radiating base flow by the transverse part. Thereby, this approach allows a precise physical definition of the acoustic source terms for computational aeroacoustics via the non-radiating base flow. In a final simulation example, Helmholtz’s decomposition of compressible flow data using the finite element method is applied to an overflowed rectangular cavity at Mach 0.8. The results show a reasonable agreement with the source data and illustrate the distinct parts of the Helmholtz decomposition.

scholarly journals Numerical and Experimental Investigation on the Structural Behaviour of a Horizontal Stabilizer under Critical Aerodynamic Loading Conditions

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
R. Sepe ◽  
R. Citarella ◽  
A. De Luca ◽  
E. Armentani
Keyword(s):  
Fem Analysis ◽  
Experimental Tests ◽  
Aerodynamic Load ◽  
Honeycomb Core ◽  
Structural Behaviour ◽  
Research Activity ◽  
Composite Sandwich ◽  
Load Vector ◽  
Definition Of ◽  
Transfer Moulding

The aim of the proposed research activity is to investigate the mechanical behaviour of a part of aerospace horizontal stabilizer, made of composite materials and undergoing static loads. The prototype design and manufacturing phases have been carried out in the framework of this research activity. The structural components of such stabilizer are made of composite sandwich panels (HTA 5131/RTM 6) with honeycomb core (HRH-10-1/8-4.0); the sandwich skins have been made by means of Resin Transfer Moulding (RTM) process. In order to assess the mechanical strength of this stabilizer, experimental tests have been performed. In particular, the most critical inflight recorded aerodynamic load has been experimentally reproduced and applied on the stabilizer. A numerical model, based on the Finite Element Method (FEM) and aimed at reducing the experimental effort, has been preliminarily developed to calibrate amplitude, direction, and distribution of an equivalent and simpler load vector to be used in the experimental test. The FEM analysis, performed by using NASTRAN code, has allowed modelling the skins of the composite sandwich plates by definition of material properties and stack orientation of each lamina, while the honeycomb core has been modelled by using an equivalent orthotropic plate. Numerical and experimental results have been compared and a good agreement has been achieved.

scholarly journals A comparison of mechanistic signaling pathway activity analysis methods

2018 ◽  
Vol 20 (5) ◽  
pp. 1655-1668 ◽  
Author(s):  
Alicia Amadoz ◽  
Marta R Hidalgo ◽  
Cankut Çubuk ◽  
José Carbonell-Caballero ◽  
Joaquín Dopazo
Keyword(s):  
Cell Activity ◽  
New Paradigm ◽  
Pathway Activity ◽  
Pathway Enrichment ◽  
New Methods ◽  
Mechanistic Pathway ◽  
Main Challenge ◽  
Definition Of ◽  
Cell Functionality ◽  
Modular Nature

Abstract Understanding the aspects of cell functionality that account for disease mechanisms or drug modes of action is a main challenge for precision medicine. Classical gene-based approaches ignore the modular nature of most human traits, whereas conventional pathway enrichment approaches produce only illustrative results of limited practical utility. Recently, a family of new methods has emerged that change the focus from the whole pathways to the definition of elementary subpathways within them that have any mechanistic significance and to the study of their activities. Thus, mechanistic pathway activity (MPA) methods constitute a new paradigm that allows recoding poorly informative genomic measurements into cell activity quantitative values and relate them to phenotypes. Here we provide a review on the MPA methods available and explain their contribution to systems medicine approaches for addressing challenges in the diagnostic and treatment of complex diseases.

Displacement-Based Seismic Design of Steel Frames Strengthened by Buckling-Restrained Braces

2012 ◽  
Vol 217-219 ◽  
pp. 1114-1118 ◽  
Author(s):  
Marco Valente
Keyword(s):  
Steel Frames ◽  
Design Procedure ◽  
Steel Frame ◽  
Seismic Retrofitting ◽  
Target Displacement ◽  
Earthquake Excitation ◽  
Capacity Spectrum ◽  
Buckling Restrained Braces ◽  
Displacement Based ◽  
Nonlinear Dynamic Analyses

This study presents a displacement-based design procedure for seismic retrofitting of steel frames using buckling-restrained braces (BRB) to meet a given target displacement in the framework of the capacity spectrum method. The seismic performance of a six-storey steel frame equipped with BRB is investigated. Different storey-wise BRB distribution methods are proposed and the influence on the results of the design procedure is analyzed. Nonlinear dynamic analyses demonstrate the efficacy of the design procedure showing the improvements achieved by the retrofitting intervention using BRB. The maximum top displacement registered for the retrofitted frame under earthquake excitation coincides with the target displacement obtained in accordance with the design procedure. The introduction of buckling-restrained braces enhances the earthquake resistance of the steel frame, providing significant energy dissipation and the stiffness needed to satisfy structural drift limits.

TRIAL CONSTRUCTION FOR SEISMIC RETROFIT BY CFT BRACE ON AN ISOLATED ISLAND

2015 ◽  
Vol 2 (1) ◽  
Author(s):  
Hiroyuki Nakahara ◽  
Yukiko Ashida
Keyword(s):  
Low Cost ◽  
Seismic Retrofit ◽  
Seismic Retrofitting ◽  
Load Carrying Capacity ◽  
Loading Test ◽  
Existing Structures ◽  
Heavy Equipment ◽  
Load Carrying ◽  
Rc Building ◽  
Set Up

The authors have been developing a seismic retrofitting method using concrete-filled steel tubular (CFT) members as a diagonal brace. The features of the method are easy set-up and low-cost because we made the enforcing devices lightweight and a simple connecting method to the existing structures. This method provides many advantages for the buildings located at the places where are difficult to transport heavy materials and equipment. An experimental construction for the seismic retrofit was conducted at the 2-story RC building on an isolated island in Japan. The construction was succeeded by only three persons in two days without heavy equipment. This paper is consisted of the reports of the constructing process and the loading test of the connecting part of the method. The trial construction includes a new detail of the connection. Two specimens were made and tested to estimate the lateral load carrying capacity of the connection.

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