scholarly journals Seismic and Energy Integrated Retrofitting of Existing Buildings with an Innovative ICF-Based System: Design Principles and Case Studies

2021 ◽  
Vol 13 (16) ◽  
pp. 9363
Author(s):  
Valentina Pertile ◽  
Alberto Stella ◽  
Lorenzo De Stefani ◽  
Roberto Scotta

This work proposes an innovative integrated retrofitting system aiming to improve both the seismic and energy performance of existing reinforced concrete and masonry buildings. The system is based on engineered insulating concrete form panels, installed on the outside of existing buildings as a shell exoskeleton. A key major advantage of the proposed system is that it addresses the contemporary improvement of seismic and energy performances of existing buildings in a single installation stage, operating exclusively from outside of the building. The insulating formworks are ad hoc prefabricated in a factory on the base of the specific geometry of the existing buildings so as to greatly maximize the ratio between overall retrofitting benefits and costs and at the same time to simplify the installation procedures. The objectives of the presented research are, on one hand, to highlight the major structural issues that the system aims to address, and on the other hand to illustrate the main characteristics and combined benefits of the proposed retrofitting system. From a structural point of view, the proposed system is conceived to behave as a non-dissipative structure with regard to seismic actions, and the lateral strength and stiffness of the structural elements are designed accordingly. An analytical design approach is proposed and validated using the available data from an experimental test performed on a full-scale simple building. Moreover, numerical modeling strategies for the proposed system are illustrated for two complex case study buildings. The results of the analyses show a considerable increase in lateral stiffness of the retrofitted buildings that, considering the non-dissipative behavior of the elements, leads to a relevant reduction of seismic deformation demand on existing structural elements.

Author(s):  
Kenny W. Q. Low ◽  
Chun Hean Lee ◽  
Antonio J. Gil ◽  
Jibran Haider ◽  
Javier Bonet

AbstractThis paper presents a new Smooth Particle Hydrodynamics computational framework for the solution of inviscid free surface flow problems. The formulation is based on the Total Lagrangian description of a system of first-order conservation laws written in terms of the linear momentum and the Jacobian of the deformation. One of the aims of this paper is to explore the use of Total Lagrangian description in the case of large deformations but without topological changes. In this case, the evaluation of spatial integrals is carried out with respect to the initial undeformed configuration, yielding an extremely efficient formulation where the need for continuous particle neighbouring search is completely circumvented. To guarantee stability from the SPH discretisation point of view, consistently derived Riemann-based numerical dissipation is suitably introduced where global numerical entropy production is demonstrated via a novel technique in terms of the time rate of the Hamiltonian of the system. Since the kernel derivatives presented in this work are fixed in the reference configuration, the non-physical clumping mechanism is completely removed. To fulfil conservation of the global angular momentum, a posteriori (least-squares) projection procedure is introduced. Finally, a wide spectrum of dedicated prototype problems is thoroughly examined. Through these tests, the SPH methodology overcomes by construction a number of persistent numerical drawbacks (e.g. hour-glassing, pressure instability, global conservation and/or completeness issues) commonly found in SPH literature, without resorting to the use of any ad-hoc user-defined artificial stabilisation parameters. Crucially, the overall SPH algorithm yields equal second order of convergence for both velocities and pressure.


2021 ◽  
Vol 13 (14) ◽  
pp. 7887
Author(s):  
Verónica Muñoz-Arroyave ◽  
Miguel Pic ◽  
Rafael Luchoro-Parrilla ◽  
Jorge Serna ◽  
Cristòfol Salas-Santandreu ◽  
...  

The aim of this research was to study from a multidimensional point of view (decisional, relational and energetic) the interpersonal relationships established by girls and boys in the traditional sport game of Elbow Tag. Scientific evidence has shown that Traditional Sport Games (TSG) trigger different effects on male and female genders in relation to emotional experiences, decision-making, conflicts and motor relationships. Despite the fact that these dimensions are intertwined, there are hardly any studies that interpret motor behaviors holistically, i.e., taking a multidimensional (360°) view of these dimensions. For this study, a quasi-experimental design was used and a type III design was applied, inspired by the observational methodology N/P/M. A total of 147 university students participated (M = 19.6, SD = 2.3): 47 girls (31.97%) and 100 boys (68.02%). A mixed ‘ad hoc’ registration system was designed with acceptable margins of data quality. Cross-tabulations, classification trees and T-patterns analysis were applied. The results indicated that social interactions between girls and boys in a mixed group were unequal. This difference was mainly due to decision-making (sub-role variable), which has much greater predictive power than the energetic variables (MV and steps).


Energies ◽  
2018 ◽  
Vol 11 (4) ◽  
pp. 1016 ◽  
Author(s):  
Mauro Venturini ◽  
Stefano Alvisi ◽  
Silvio Simani ◽  
Lucrezia Manservigi

This paper deals with the comparison of different methods which can be used for the prediction of the performance curves of pumps as turbines (PATs). The considered approaches are four, i.e., one physics-based simulation model (“white box” model), two “gray box” models, which integrate theory on turbomachines with specific data correlations, and one “black box” model. More in detail, the modeling approaches are: (1) a physics-based simulation model developed by the same authors, which includes the equations for estimating head, power, and efficiency and uses loss coefficients and specific parameters; (2) a model developed by Derakhshan and Nourbakhsh, which first predicts the best efficiency point of a PAT and then reconstructs their complete characteristic curves by means of two ad hoc equations; (3) the prediction model developed by Singh and Nestmann, which predicts the complete turbine characteristics based on pump shape and size; (4) an Evolutionary Polynomial Regression model, which represents a data-driven hybrid scheme which can be used for identifying the explicit mathematical relationship between PAT and pump curves. All approaches are applied to literature data, relying on both pump and PAT performance curves of head, power, and efficiency over the entire range of operation. The experimental data were provided by Derakhshan and Nourbakhsh for four different turbomachines, working in both pump and PAT mode with specific speed values in the range 1.53–5.82. This paper provides a quantitative assessment of the predictions made by means of the considered approaches and also analyzes consistency from a physical point of view. Advantages and drawbacks of each method are also analyzed and discussed.


2015 ◽  
Vol 812 ◽  
pp. 375-380 ◽  
Author(s):  
D. Pósalaky ◽  
János Lukács

The magnitude of different aluminium alloys, especially the ones with higher strength, are increasing in the structural engineering, not just the usual applications (like the aerospace industry) but more likely in the automotive industry. There are more assumptions of the effective use of aluminium; we should highlight two important factors, the technological and the applicability criterions. The technological criterion is the joining of structural elements, frequently with welding thus the technological criterion ultimately is the weldability. The assumption of applicability comes from the loading capability of these structures, which is typically cyclic loading so the key issue from the point of view of applicability is the resistance to fatigue. This article represents physical simulation and fatigue test results both on the base material and on the welded joints.


2018 ◽  
Vol 10 (7) ◽  
pp. 2548 ◽  
Author(s):  
Mariangela De Vita ◽  
Paolo Beccarelli ◽  
Eleonora Laurini ◽  
Pierluigi De Berardinis

The aim of this research, carried out in collaboration with Maco Technology Inc., was to analyse the energy performance of temporary textile structures that are often used to host itinerant events. This paper illustrates the dynamic simulations carried on the Ducati Pavilion, designed by Maco Technology, which hosted Ducati staff during the different stages of the Superbike World Championship. Specific aspects relating to the structural/constructive system of the project were also analysed. The theme of energy saving and carbon reduction is of great importance in temporary and itinerant structures and environmental sustainability in relation to the materials used, storage, re-use, mode of transport and ability to respond efficiently to the climatic conditions of the installation sites is an important aspect. The Ducati Pavilion was modelled and analysed from an energy point of view using Design Builder software. Ways of improving performance were analysed under summer conditions. The paper focuses on the importance of optimizing the performance of textile envelopes: the methodology proposed allows visible savings in terms of energy consumption and achieves good levels of environmental comfort in temporary buildings with low thermal mass structure.


2017 ◽  
Vol 1 (2) ◽  
pp. 36 ◽  
Author(s):  
Hector Hernández

In order to improve the energy performance of buildings, the need to value economically investments of energy efficiency associated with the rehabilitation of dwellings arises. This point of view provides an useful tool for analysts who start in the economic appraisal of energy efficiency investments. The present research gives a conceptual framework for the economic assessment of these types of investments in dwellings. As a result, it is possible to identify two techniques in the appraisals of this nature: dynamic and static approaches. Both methods contrast the benefits (energy savings) with the costs of investments over time. However, they differentiate the opportunity and the moment when investment must be carried out given an uncertainty scenario. This conceptual precision allows the study of several publications where different alternatives in retrofitting houses where evaluated, confirming the considerations that must be taken into account when economic modelling is made: the type of approach to be used (dynamic or static) and; at the definition of the investment alternatives and scenarios, the aspects of time, irrevocability and uncertainty.ResumenEn pro de la mejora del desempeño energético de los edificios, surge la necesidad de evaluar económicamente las inversiones de eficiencia energética asociadas a la rehabilitación de viviendas. Este punto de vista trata de ser una herramienta útil para analistas que se inicien en la evaluación económica de inversiones en eficiencia energética. La presente investigación muestra un marco conceptual de la evaluación económica de este tipo de inversiones en viviendas. Como resultado, es posible identificar dos enfoques presentes en los análisis económicos de esta naturaleza: el dinámico y el estático. Ambos métodos contrastan los beneficios (ahorros energéticos) con los costes de las inversiones en el tiempo. Sin embargo, diferencian la oportunidad y el momento en que la inversión debe realizarse dado un escenario de incertidumbre. Esta precisión conceptual permite estudiar varias publicaciones donde se evaluaron diferentes alternativas de reacondicionamiento en viviendas, confirmándose las consideraciones que deben tenerse presentes en momento de realizar la modelación económica: el tipo de enfoque a usar (dinámico o estático) y, en la definición de las alternativas de inversión y escenarios, los aspectos de tiempo, irrevocabilidad e incertidumbre.


Author(s):  
Sisaynew Tesfaw Admassu

To resistance, the lateral load from wind or an earthquake is that the reason for the evolution of varied structural systems. Because, when a medium or any multi-level structure is exposed to horizontal or torsional deflections under the action of seismic burdens. Lateral stiffness is a major consideration in the design of the buildings. In addition to this, many existing steel buildings and reinforced concrete buildings for which the weak lateral stiffness is the main problem; should be retrofitted to conquer the insufficiencies to resist the lateral loading. Lateral load resisting systems are structural elements providing basic lateral strength and stiffness, without which the structure would be laterally unstable. The unstable nature of the structure is solved by the fitting arrangement of bracings systems. A bracing system is that forms an integral part of the frame. Thus, such a structure has to be analyzed before arriving at the best type or effective arrangement of bracing. Bracing is a highly effective strategy of resisting lateral forces in a frame structure. In this document, a ten-story building with incorporated bracing systems is analysed using ETABS 2016 analysis software as per Eurocode and Ethiopian Building Code Standards (EBCS). Then, the lateral displacement is evaluated under each of the bracing types.


2018 ◽  
Vol 24 (3) ◽  
pp. 1200-1214 ◽  
Author(s):  
Robert BUCOŃ ◽  
Michał TOMCZAK

The problem of multi-family building maintenance is complex and comprises numerous issues, one of which is the process of planning expenditures for residential building renovation. This task is important from the manager’s point of view as their responsibility is to maintain a building in a non-deteriorated condition. To fulfil this task, the authors of this paper suggest utilising a decision-making model aimed at defining renovation activities making it possible to retain the maintenance standard (as regards newly commissioned residential buildings) or improve it (as regards existing buildings). The suggested model is based on a multi-criteria building assessment including seven requirements. The calculations conducted using the suggested model enable us to define the costs and scope of renovation taken to ensure the assumed building condition or, by assuming various rates paid to the renovation reserve, to define the period in which the above-mentioned goals may be achieved.


2021 ◽  
Vol 25 (3) ◽  
pp. 332-341
Author(s):  
I. V. Fokin ◽  
A. N. Smirnov

The aim was to create a mathematical model describing the development of a production (shop-to-shop) routing of mechanical engineering products based on a 3D model and allowing the cost of the final product to be reduced. The developed mathematical model was simulated based on 3D models designed in the Siemens NX system, which were subsequently imported into the *stp format and recognized by a designed module written in the Phyton programming language. The factors of the production environment affecting the formation of the production routing of mechanical engineering products were determined. A diagram of the algorithm for the “constructive element - technological operation - means of technological equipment (equipment-tool)” relationship was developed. Based on the results of testing the developed mathematical model, the use of neural networks as a tool for the implementation and automation of the work was found advantageous as compared to the standard scheme of work of a process engineer when developing a production routing of mechanical engineering products. These advantages include a decrease in the time for the development of a routing and the cost of the final product. The developed model has a practical limitation consisting in a rather complex geometry of some structural elements of a unit, which impedes the development of an algorithm for recognizing their structure. The use of a neural network prototype in automatic mode is advisable for relatively simple parts (including a flange, hole, chamfer and rounding). However, since the number of simple units from the recognition point of view amounts to about 40% among the nomenclature of manufactured units, the reduction in the development time of the technological process in comparison with the conventional approach comprises only 10–25% of the total time of technological preparation.


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