Sustainable architecture and earthquake resilience of vernacular Zegalli houses in northern Iran

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Mona Zaryoun ◽  
Mahmood Hosseini ◽  
Kaveh Soleymani

PurposeThe main purpose of this study is revival of vernacular architecture of Zegalli houses, which can be beneficial in several aspects of sustainable architecture, and therefore, its reuse in contemporary architecture can be strongly recommended. Zegalli houses, in northern Iran, are almost-entirely wooden vernacular houses, which beside to having several aspects of sustainable architecture, have shown good resistance against past earthquakes. Their relatively good seismic performance is mainly because of their specific timber foundation, which creates a kind of rocking/rolling isolation, as well as their light weight and diagonally braced stiff walls.Design/methodology/approachIn this paper, first the architectural features of Zegalli houses, particularly energy efficiency, sustainability and eco-friendliness are described. Then, their structural system, focusing more on their foundation, is discussed. Finally, a simplified model of the house, developed in a powerful finite element analysis program, is introduced, and sample results of a series of time history analyses (THA), employing three-component accelerograms of three selected earthquakes, are presented.FindingsResults of THA show that the rocking/rolling behavior of foundation timbers in various levels significantly reduces seismic response of the house, leading to its stability against earthquakes with peak ground acceleration up to 0.25 g.Practical implicationsRegarding the architectural and structural merits of Zegalli houses, they can be considered as sustainable vernacular architecture, and therefore, architects and civil and structural engineers are encouraged to reconsider the use of these houses, with some modifications, in future developments.Originality/value3D dynamics analysis of Shikilli foundations of Zegalli houses is done for the first time in this study.

2015 ◽  
Vol 32 (7) ◽  
pp. 2100-2119 ◽  
Author(s):  
Ali Johari ◽  
Jaber Rezvani Pour ◽  
Akbar Javadi

Purpose – Liquefaction of soils is defined as significant reduction in shear strength and stiffness due to increase in pore water pressure. This phenomenon can occur in static (monotonic) or dynamic loading patterns. However, in each pattern, the inherent variability of the soil parameters indicates that this problem is of a probabilistic nature rather than being deterministic. The purpose of this paper is to present a method, based on random finite element method, for reliability assessment of static liquefaction of saturated loose sand under monotonic loading. Design/methodology/approach – The random finite element analysis is used for reliability assessment of static liquefaction of saturated loose sand under monotonic loading. The soil behavior is modeled by an elasto-plastic effective stress constitutive model. Independent soil parameters including saturated unit weight, peak friction angle and initial plastic shear modulus are selected as stochastic parameters which are modeled using a truncated normal probability density function (pdf). Findings – The probability of liquefaction is assessed by pdf of modified pore pressure ratio at each depth. For this purpose pore pressure ratio is modified for monotonic loading of soil. It is shown that the saturated unit weight is the most effective parameter, within the selected stochastic parameters, influencing the static soil liquefaction. Originality/value – This research focuses on the reliability analysis of static liquefaction potential of sandy soils. Three independent soil parameters including saturated unit weight, peak friction angle and initial plastic shear modulus are considered as stochastic input parameters. A computer model, coded in MATLAB, is developed for the random finite element analysis. For modeling of the soil behavior, a specific elasto-plastic effective stress constitutive model (UBCSAND) was used.


2014 ◽  
Vol 44 (3) ◽  
pp. 223-229 ◽  
Author(s):  
Issa Gholampour Azizi ◽  
Hassan Ghadi ◽  
Samaneh Rouhi

Purpose – OTA is primarily produced by species of Penicillium and Aspergillus. This toxin has been detected worldwide in different grains such as rice. Due to OTA's toxicity and its effects on human's health, the authors performed this study to analyze the OTA's contamination levels in rice samples that gathered in different cities of Mazandaran (a province in northern Iran). The paper aims to discuss these issues. Design/methodology/approach – In this study, 80 rice samples were collected from several cities of Mazandaran. Data were analyzed using CD-ELISA method for OTA. Conjugated enzyme was added to uncoated-antibody wells and standard solution and sample extract were added to it. Solutions were transferred to the coated-antibody wells. Then, substrate was added to produce blue color. Finally, stopping solution was added to stop the reaction. The color intensity was inversely proportional to the OTA concentration, measured with the ELISA reader and calculated by analysis of variance by using the SPSS software package. Findings – None of the samples that were collected in Mazandaran were contaminated with >5 μg/kg of OTA in October. Also none of the samples from Amol, Fereydonkenar, Babol or Behshahr were contaminated with >5 μg/kg of this toxin in November. But in sari, Nowshahr and Ramsar the authors encountered samples that had >5 μg/kg of OTA contamination which is more than the acceptable limit. Practical implications – Screening and analyzing the rice fields are vital to detect any OTA contamination and can be effective for removing the contaminated rice. So proper strategies and management tactics are required in order to prevent OTA production in rice fields in pre- and post-harvest time and people must share their experiences regarding fighting this contamination. Originality/value – Since rice is used extensively all over the world, consumption of contaminated rice causes diseases for humans. Therefore, determination, management, and prevention of OTA should be considered seriously.


2013 ◽  
Vol 756-759 ◽  
pp. 4482-4486
Author(s):  
Chun Gan ◽  
Xue Song Luo

In recent years, frequent earthquakes have caused great casualties and economic losses in China. And in the earthquake, damage of buildings and the collapse is the main reason causing casualties. Therefore, in the design of constructional engineering, a seismicity of architectural structure is the pressing task at issue. Through time history analysis method, this paper analyzes the time history of building structural response and then it predicts the peak response of mode by response spectrum analysis. Based on this, this paper constructs a numerical simulation model for the architecture by using finite element analysis software SATWE. At the same time, this paper also calculates the structure seismic so as to determine the design of each function structure in architectural engineering design and then provides reference for the realization of earthquake-resistant building.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Juan María Songel

PurposeThe aim of this paper is to explore the relationship between vernacular architecture and Frei Otto's work, searching for shared principles and specific singularities, and testing whether lightness and sustainability can be identified as a common goal.Design/methodology/approachThe study is focused on tents and yurts, as archetypal examples of traditional architecture, and membrane structures and gridshells, as two types of light structures developed by Frei Otto. A comparative analysis of their behavior, form, elements, types, materials and strength has been carried out.FindingsThe survey carried out shows that Frei Otto's innovative tents and gridshells were not based on form imitation of vernacular architecture, but rather on a thorough understanding of physical form-generating processes, driving specific materials to optimal form, like his experiments with soap film models to generate tensioned minimal surfaces or his experiments with hanging chain net models to generate compressive antifunicular lattice shells.Originality/valueThis paper highlights how Frei Otto's endeavor to get the maximum with the minimum, to achieve a lot from a little, is also a key target of lightness and sustainability, and an essential feature of vernacular architecture.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Bin Zheng ◽  
Yi Cai ◽  
Kelun Tang

Purpose The purpose of this paper is to realize the lightweight of connecting rod and meet the requirements of low energy consumption and vibration. Based on the structural design of the original connecting rod, the finite element analysis was conducted to reduce the weight and increase the natural frequencies, so as to reduce materials consumption and improve the energy efficiency of internal combustion engine. Design/methodology/approach The finite element analysis, structural optimization design and topology optimization of the connecting rod are applied. Efficient hybrid method is deployed: static and modal analysis; and structure re-design of the connecting rod based on topology optimization. Findings After the optimization of the connecting rod, the weight is reduced from 1.7907 to 1.4875 kg, with a reduction of 16.93%. The maximum equivalent stress of the optimized connecting rod is 183.97 MPa and that of the original structure is 217.18 MPa, with the reduction of 15.62%. The first, second and third natural frequencies of the optimized connecting rod are increased by 8.89%, 8.85% and 11.09%, respectively. Through the finite element analysis and based on the lightweight, the maximum equivalent stress is reduced and the low-order natural frequency is increased. Originality/value This paper presents an optimization method on the connecting rod structure. Based on the statics and modal analysis of the connecting rod and combined with the topology optimization, the size of the connecting rod is improved, and the static and dynamic characteristics of the optimized connecting rod are improved.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Reza Askarizad ◽  
Akram Dadashpour ◽  
Javad Faghirnavaz ◽  
Jinliao He ◽  
Hossein Safari

PurposeThe vulnerability of worn-out textures in the face of natural disasters is one of the most significant challenges that have forced planners and urban managers to intervene in these structures. In this context, the new-urbanism, or the new urbanization, movement is one of the most novel approaches. This paper aims to organizing one of the worn-out neighborhoods in Rudsar, northern Iran with an approach toward the new urbanism.Design/methodology/approachThe procedure adopted in this research is a combination of both quantitative and qualitative practices with an applied approach. Therefore, through utilizing the analytical hierarchy process (AHP) and space syntax methods, the principles of the new urbanism are examined using the Expert Choice and Depthmap software. Subsequently, the appropriate priorities are mentioned for organizing the neighborhood with the new-urbanism approach using the building information system (BIM) and strengths, weaknesses, opportunities and threats (SWOT) techniques.FindingsThe findings of this study indicate that among the main characteristics of the new urbanism, walkability is recognized as the most important factor. Afterward, the components of maintaining the traditional structure of neighborhoods and connectivity were in the second and third ranks, respectively, of importance. Accordingly, by identifying the societal potential of roads according to their spatial configuration, it is possible to boost walkability, as well as economic prosperity in these areas.Originality/valueThe combination and correlation of the four utilized methods in this research can be adopted in the future studies as a new outlook of the mixed methods in the field of urban studies.


Author(s):  
Tanushree Agarwal ◽  
Fatemeh Rahmani ◽  
Ishtique Zaman ◽  
Federico Gasbarri ◽  
Keivan Davami ◽  
...  

Purpose This paper aims to develop a comprehensive model of a magnetic sensor array that will be operational for a multitude of electric components in continuous and nonintrusive condition monitoring (CM) or in readiness assessment (RA) applications. Design/methodology/approach A universal nonintrusive model of a flexible antenna array is introduced to monitor and identify failures in electric machine drives. An adjustable sensor is designed to serve as a RA for a vast range of electrical elements in a typical power system by capturing the low-frequency radiated magnetic fields. Findings The optimal placement of the most sensitive radiated fields from several components has been discovered in this case study, enabling the detection of healthy current flow throughout. Thereafter, the short-circuit investigation, representing faulty situations, is implemented and compared with healthy cases. Practical implications This sensing technique can be used for nonintrusive CM of components that are out of reach and cannot have the sensor to be held around it such as components in offshore winds, wind energy generation and power and chemical plants. Originality/value The results are provided for three commonly used machines with a single sensor array with numerous settings. The three dimensional (3 D) finite element analysis is applied in the structuring of the sensor, detection of the optimum location and recognition of faults in the machines. Finally, based on the setup design, 3 D printing is used for the construction of the sensor array. Thus, the sensor array with fault detection avoids major component failures and increases system reliability/resiliency.


2019 ◽  
Vol 17 (1) ◽  
pp. 25-40 ◽  
Author(s):  
Hafida Kahoul ◽  
Samira Belhour ◽  
Ahmed Bellaouar ◽  
Jean Paul Dron

Purpose This paper aims to present the fatigue life behaviour of upper arm suspension. The main objectives are to predict the fatigue life of the component and to identify the critical location. In this analysis, three aluminium alloys were used for the suspension, and their fatigue life was compared to select the suitable material for the suspension arm. Design/methodology/approach CAD model was prepared using Solid Works software, and finite element analysis was done using ANSYS 14.0 software by importing the Parasolid file to ANSYS. The model is subjected to loading and boundary conditions; the authors consider a vertical force with constant amplitude applied at the bushing that connected to the tire, the others two bushing that connected to the body of the car are constraint. Tetrahedral elements given enhanced results as compared to other types of elements; therefore, the elements (TET 10) are used. The maximum principal stress was considered in the linear static analysis, and fatigue analysis was done using strain life approach. Findings Life and damage are evaluated and the critical location was considered at node 63,754. From the fatigue analysis, aluminium alloys 7175-T73 (Al 90%-Zn 5.6%-Mg 2.5% -… …) and 2014-T6 (Al 93.5%-Cu 4.4%-Mg 0.5%… …) present a similar behaviour as compared to 6061-T6 (Al 97.9%-Mg 1.0%-Si 0.6%… … .); in this case of study, these lather are considered to be the materials of choice to manufacture the suspension arms; but 7175-T73 aluminium alloys remain the material with a better resistance to fatigue. Originality/value By the finite element analysis method and assistance of ANSYS software, it is able to analyse the different car components from varied aspects such as fatigue, and consequently save time and cost. For further research, the experimental works under controlled laboratory conditions should be done to determine the validation of the result from the software analysis.


2019 ◽  
Vol 71 (1) ◽  
pp. 94-101 ◽  
Author(s):  
Yanzhong Wang ◽  
Yuan Li ◽  
Yang Liu ◽  
Wei Zhang

PurposeTo gain in-depth understandings of engaging characteristics, the purpose of this paper is to improve the model of wet clutches to predict the transmitted torque during the engagement process.Design/methodology/approachThe model of wet clutch during the engagement process took main factors into account, such as the centrifugal effect of lubricant, permeability of friction material, slippage factor of lubricant on contact surface and roughness of contact surface. Reynolds’ equation was derived to describe the hydrodynamic lubrication characteristics of lubricant film between the friction plate and the separated plate, and an elastic-plastic model of the rough surfaces contact based on the finite element analysis was used to indicate the loading force and friction torque of the contact surface.FindingsThe dynamic characteristics of wet clutch engagement time, relative speed, hydrodynamic lubrication of lubricating oil, rough surface contact load capacity and transfer torque can be obtained by the wet clutch engagement model. And the influence of the groove shape and depth on the engaging characteristics is also analyzed.Originality/valueThe mathematical model of the wet clutch during the engagement process can be used to predict the engaging characteristics of the wet clutch which could be useful to the design of the wet clutch.


2014 ◽  
Vol 24 (8) ◽  
pp. 1888-1905 ◽  
Author(s):  
M.M. Rahman ◽  
Hakan Oztop ◽  
S. Mekhilef ◽  
R. Saidur ◽  
A. Chamkha ◽  
...  

Purpose – The purpose of this paper is to examine the effects of thick wall parameters of a cavity on combined convection in a channel. In other words, conjugate heat transfer is solved. Design/methodology/approach – Galerkin weighted residual finite element method is used to solve the governing equations of mixed convection. Findings – The streamlines, isotherms, local and average Nusselt numbers are obtained and presented for different parameters. It is found heat transfer is an increasing function of dimensionless thermal conductivity ratio. Originality/value – The literature does not have mixed convection and conjugate heat transfer problem in a channel with thick walled cavity.


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