Search results for: building material
7712 Laying the Proto-Ontological Conditions for Floating Architecture as a Climate Adaptation Solution for Rising Sea Levels: Conceptual Framework and Definition of a Performance Based Design
Authors: L. Calcagni, A. Battisti, M. Hensel, D. S. Hensel
Abstract:
Since the beginning of the 21st century, we have seen a dynamic growth of water-based (WB) architecture, mainly due to the increasing threat of floods caused by sea level rise and heavy rains, all correlated with climate change. At the same time, the shortage of land available for urban development also led architects, engineers, and policymakers to reclaim the seabed or to build floating structures. Furthermore, the drive to produce energy from renewable resources has expanded the sector of offshore research, mining, and energy industry which seeks new types of WB structures. In light of these considerations, the time is ripe to consider floating architecture as a full-fledged building typology. Currently, there is no universally recognized academic definition of a floating building. Research on floating architecture lacks a proper, commonly shared vocabulary and typology distinction. Moreover, there is no global international legal framework for urban development on water, and there is no structured performance based building design (PBBD) approach for floating architecture in most countries, let alone national regulatory systems. Thus, first of all, the research intends to overcome the semantic and typological issues through the conceptualization of floating architecture, laying the proto-ontological conditions for floating development, and secondly to identify the parameters to be considered in the definition of a specific PBBD framework, setting the scene for national planning strategies. The theoretical overview and re-semanticization process involve the attribution of a new meaning to the term floating architecture. This terminological work of semantic redetermination is carried out through a systematic literature review and involves quantitative and historical research as well as logical argumentation methods. As it is expected that floating urban development is most likely to take place as an extension of coastal areas, the needs and design criteria are definitely more similar to those of the urban environment than to those of the offshore industry. Therefore, the identification and categorization of parameters –looking towards the potential formation of a PBBD framework for floating development– takes the urban and architectural guidelines and regulations as the starting point, taking the missing aspects, such as hydrodynamics (i.e. stability and buoyancy) from the offshore and shipping regulatory frameworks. This study is carried out through an evidence-based assessment of regulatory systems that are effective in different countries around the world, addressing on-land and on-water architecture as well as offshore and shipping industries. It involves evidence-based research and logical argumentation methods. Overall, inhabiting water is proposed not only as a viable response to the problem of rising sea levels, thus as a resilient frontier for urban development, but also as a response to energy insecurity, clean water, and food shortages, environmental concerns, and urbanization, in line with Blue Economy principles and the Agenda 2030. This review shows how floating architecture is to all intents and purposes, an urban adaptation measure and a solution towards self-sufficiency and energy-saving objectives. Moreover, the adopted methodology is, to all extents, open to further improvements and integrations, thus not rigid and already completely determined. Along with new designs and functions that will come into play in the practice field, eventually, life on water will seem no more unusual than life on land, especially by virtue of the multiple advantages it provides not only to users but also to the environment.Keywords: adaptation measures, building typology, floating architecture, performance based building design, rising sea levels
Procedia PDF Downloads 977711 Building Resilience to El Nino Related Flood Events in Northern Peru Using a Structured Facilitation Approach to Interdisciplinary Problem Solving
Authors: Roger M. Wall, David G. Proverbs, Yamina Silva, Danny Scipion
Abstract:
This paper critically reviews the outcomes of a 4 day workshop focused on building resilience to El Niño related Flood Events in northern Perú. The workshop was run jointly by Birmingham City University (BCU) in partnership with Instituto Geofísico del Perú (IGP) and was hosted by the Universidad de Piura (UDEP). The event took place in August 2018 and was funded by the Newton-Paulet fund administered by the British Council. The workshop was a response to the severe flooding experienced in Piura during the El Niño event of March 2017 which damaged over 100,000 homes and destroyed much local infrastructure including around 100 bridges. El Niño is a recurrent event and there is concern that its frequency and intensity may change in the future as a consequence of climate change. A group of 40 early career researchers and practitioners from the UK and Perú were challenged with working together across disciplines to identify key cross-cutting themes and make recommendations for building resilience to similar future events. Key themes identified on day 1 of the workshop were governance; communities; risk information; river management; urban planning; health; and infrastructure. A field study visit took place on day 2 so that attendees could gain first-hand experience of affected and displaced communities. Each of the themes was then investigated in depth on day 3 by small interdisciplinary teams drawing on their own expertise, local knowledge and the experiences of the previous day’s field trip. Teams were responsible for developing frameworks for analysis of their chosen theme and presenting their findings to the whole group. At this point, teams worked together to develop links between the different themes so that an integrated approach could be developed and presented on day 4. This paper describes the approaches taken by each team and the way in which these were integrated to form an holistic picture of the whole system. The findings highlighted the importance of risk-related information and the need for strong governance structures to enforce planning regulations and development. The structured facilitation approach proved to be very effective and it is recommended that the process be repeated with a broader group of stakeholders from across the region.Keywords: El Niño, integrated flood risk management, Perú, structured facilitation, systems approach, resilience
Procedia PDF Downloads 1477710 Unfolding Architectural Assemblages: Mapping Contemporary Spatial Objects' Affective Capacity
Authors: Panagiotis Roupas, Yota Passia
Abstract:
This paper aims at establishing an index of design mechanisms - immanent in spatial objects - based on the affective capacity of their material formations. While spatial objects (design objects, buildings, urban configurations, etc.) are regarded as systems composed of interacting parts, within the premises of assemblage theory, their ability to affect and to be affected has not yet been mapped or sufficiently explored. This ability lies in excess, a latent potentiality they contain, not transcendental but immanent in their pre-subjective aesthetic power. As spatial structures are theorized as assemblages - composed of heterogeneous elements that enter into relations with one another - and since all assemblages are parts of larger assemblages, their components' ability to engage is contingent. We thus seek to unfold the mechanisms inherent in spatial objects that allow to the constituent parts of design assemblages to perpetually enter into new assemblages. To map architectural assemblage's affective ability, spatial objects are analyzed in two axes. The first axis focuses on the relations that the assemblage's material and expressive components develop in order to enter the assemblages. Material components refer to those material elements that an assemblage requires in order to exist, while expressive components includes non-linguistic (sense impressions) as well as linguistic (beliefs). The second axis records the processes known as a-signifying signs or a-signs, which are the triggering mechanisms able to territorialize or deterritorialize, stabilize or destabilize the assemblage and thus allow it to assemble anew. As a-signs cannot be isolated from matter, we point to their resulting effects, which without entering the linguistic level they are expressed in terms of intensity fields: modulations, movements, speeds, rhythms, spasms, etc. They belong to a molecular level where they operate in the pre-subjective world of perceptions, effects, drives, and emotions. A-signs have been introduced as intensities that transform the object beyond meaning, beyond fixed or known cognitive procedures. To that end, from an archive of more than 100 spatial objects by contemporary architects and designers, we have created an effective mechanisms index is created, where each a-sign is now connected with the list of effects it triggers and which thoroughly defines it. And vice versa, the same effect can be triggered by different a-signs, allowing the design object to lie in a perpetual state of becoming. To define spatial objects, A-signs are categorized in terms of their aesthetic power to affect and to be affected on the basis of the general categories of form, structure and surface. Thus, different part's degree of contingency are evaluated and measured and finally, we introduce as material information that is immanent in the spatial object while at the same time they confer no meaning; they only convey some information without semantic content. Through this index, we are able to analyze and direct the final form of the spatial object while at the same time establishing the mechanism to measure its continuous transformation.Keywords: affective mechanisms index, architectural assemblages, a-signifying signs, cartography, virtual
Procedia PDF Downloads 1277709 Mechanical and Thermal Characterization of Washout Tooling for Resin Transfer Molding
Authors: Zachary N. Wing
Abstract:
Compared to autoclave based processes, Resin Transfer Molding (RTM) offers several key advantages. This includes high internal and external complexity, less waste, lower volatile emissions, higher production rates, and excellent surface finish. However, the injection of high pressure-high temperature resin presents a tooling challenge in cases where trapped geometries exist. Tooling materials that can sustain these conditions and be easily removed would expand the use of RTM. We have performed research on developing an RTM suitable tooling material called 'RTMCore' for use in forming trapped geometries. RTMCore tooling materials can withstand the injection of high temperature-high pressure resin but be easily removed with tap water. RTM properties and performance capabilities are reviewed against other washout systems. Our research will cover the preliminary characterization of tooling system properties, mechanical behavior, and initial results from an RTM manufacturing trial. Preliminary results show the material can sustain pressures greater than 13 MPa and temperatures greater than 150°C.Keywords: RTM, resin transfer molding, trapped geometries, washout tooling
Procedia PDF Downloads 1587708 Structural and Optical Properties of Ce3+ Doped YPO4: Nanophosphors Synthesis by Sol Gel Method
Authors: B. Kahouadji, L. Guerbous, L. Lamiri, A. Mendoud
Abstract:
Recently, nanomaterials are developed in the form of nano-films, nano-crystals and nano-pores. Lanthanide phosphates as a material find extensive application as laser, ceramic, sensor, phosphor, and also in optoelectronics, medical and biological labels, solar cells and light sources. Among the different kinds of rare-earth orthophosphates, yttrium orthophosphate has been shown to be an efficient host lattice for rare earth activator ions, which have become a research focus because of their important role in the field of light display systems, lasers, and optoelectronic devices. It is in this context that the 4fn- « 4fn-1 5d transitions of rare earth in insulating materials, lying in the UV and VUV, are the aim of large number of studies .Though there has been a few reports on Eu3+, Nd3+, Pr3+,Er3+, Ce3+, Tm3+ doped YPO4. The 4fn- « 4fn-1 5d transitions of the rare earth dependent to the host-matrix, several matrices ions were used to study these transitions, in this work we are suggesting to study on a very specific class of inorganic material that are orthophosphate doped with rare earth ions. This study focused on the effect of Ce3+ concentration on the structural and optical properties of Ce3+ doped YPO4 yttrium orthophosphate with powder form prepared by the Sol Gel method.Keywords: YPO4, Ce3+, 4fn- <->4fn-1 5d transitions, scintillator
Procedia PDF Downloads 3457707 Synthesis and Magnetic Properties of Six-Lines Ferrihydrite Nanoparticles
Authors: Chandni Rani, S. D. Tiwari
Abstract:
Ferrihydrite is one of the distinct minerals in the family of oxides, hydroxides and oxyhydroxides of iron. It is a nanocrystalline material. It occurs naturally in different sediments, soil systems and also found in the core of ferritin, an iron storage protien. This material can also be synthesized by suitable chemical methods in laboratories. This is known as less crystalline Iron (III) Oxyhydroxide. Due to its poor crystallinity, there are very broad peaks in x-ray diffraction. Depending on the number of peaks in x-ray diffraction pattern, it is classified as two lines and six lines ferrihydrite. The average crystallite size for these two forms is found to be about 2nm to 5nm. The exact crystal structure of this system is still under debate. Out of these two forms, the six lines ferrihydrite is more ordered in comparison to two lines ferrihydrite. The magnetic behavior of two lines ferrihydrite nanoparticles is somewhat well studied. But the magnetic behavior of six lines ferrihydrite nanoparticles could not attract the attention of researchers much. This motivated us to work on the magnetic properties of six lines ferrihydrite nanoparticles. In this work, we present synthesis, structural characterization and magnetic behavior of 5 nm six lines ferrihydrite nanoparticles. X-ray diffraction and transmission electron microscope are used for structural characterization of this system. Magnetization measurements are performed to fit the data at different temperatures. Then the effect of magnetic moment distribution is also found. All these observations are discussed in detail.Keywords: nanoparticles, magnetism, superparamagnetism, magnetic anisotropy
Procedia PDF Downloads 3397706 Production of Biodiesel from Avocado Waste in Hossana City, Ethiopia
Authors: Tarikayehu Amanuel, Abraham Mohammed
Abstract:
The production of biodiesel from waste materials is becoming an increasingly important research area in the field of renewable energy. One potential waste material source is avocado, a fruit with a large seed and peel that are typically discarded after consumption. This research aims to investigate the feasibility of using avocado waste as a feedstock for the production of biodiesel. The study focuses on extracting oil from the waste material using the transesterification technique and then characterizing the properties of oil to determine its suitability for conversion to biodiesel. The study was conducted experimentally, and a maximum oil yield of 11.583% (150g of oil produced from 1.295kg of avocado waste powder) was obtained from avocado waste powder at an extraction time of 4hr. An 87% fatty acid methyl ester (biodiesel) conversion was also obtained using a methanol/oil ratio of 6:1, 1.3g NaOH, reaction time 60min, and 65°C reaction temperature. Furthermore, from 145 ml of avocado waste oil, 126.15 ml of biodiesel was produced, indicating a high percentage of conversion (87%). Conclusively, the produced biodiesel showed comparable physical and chemical characteristics to that of standard biodiesel samples considered for the study. The results of this research could help to identify a new source of biofuel production while also addressing the issue of waste disposal in the food industry.Keywords: biodiesel, avocado, transesterification, soxhlet extraction
Procedia PDF Downloads 707705 Functioning of a Temporarily Single Parent Family System Due to Migration from the Perspective of Adolescents with Cerebral Palsy
Authors: A. Gagat-Matuła
Abstract:
There is a definite lack – in Poland, as well as around the world – of empirical studies of families raising handicapped child, in which one parent migrates. In diagnostics of the functioning of such families emphasis should be placed not only on the difficulties, but most of all it should be indicated what possibilities are there for the family and how it overcomes the difficulties. Migration of a parent on the one hand is a chance to improve the family’s material situation. In certain circumstances this may only be an “escape” into work from the issues associated with the upbringing and rehabilitation of a handicapped child. The aim of the study was to learn the functioning of a temporarily single parent family system as a result of migration of a parent from the perspective of adolescents with cerebral palsy. The study was conducted in the year 2013 in the area of Eastern Poland. It involved an analysis of 70 persons (with cerebral palsy in an intellectual capacity) from families in which at least one of the parents migrates. The study incorporated the diagnostic survey method. These tools were used: Family Evaluation Scales (SOR) adapted for Poland by Andrzej Margasiński. The explorations in this study indicate, that 47% of studied temporarily single parent families are balanced models. This is evidence of the resources at the disposal of the family which, despite the disability of the child and temporary separation, is able to function properly. The conducted studies show, that 37% of temporarily single parent families are imbalanced models in the perception of adolescents with cerebral palsy. These families experience functional difficulties and require psychological and pedagogical support. There is a need for building skills related to effective coping with family stress. Especially considering, that families of an imbalanced type do not use the internal and external resources of the family system. Such a situation may deepen the disarrangement of family life. In intermediate families (16%) there are also temporary difficulties in functioning. Separation anxiety experienced by mothers may disrupt relations and introduce additional stress factors. For that reason it is important to provide support for women with difficulties coping with the emotions associated with raising handicapped adolescents and migratory separation.Keywords: child with cerebral palsy, family, migration, parents
Procedia PDF Downloads 4197704 Utilization of a Composite of Oil Ash, Scoria, and Expanded Perlite with Polyethylene Glycol for Energy Storage Systems
Authors: Khaled Own Mohaisen, Md. Hasan Zahir, Salah U. Al-Dulaijan, Shamsad Ahmad, Mohammed Maslehuddin
Abstract:
Shape-stabilized phase change materials (ss-PCMs) for energy storage systems were developed using perlite, scoria, and oil ash as a carrier, with polyethylene glycol (PEG) with a molecular weight of 6000 as phase change material (PCM). Physical mixing using simple impregnation of ethanol evaporation technique method was carried out to fabricate the form stabilized PCM. The fabricated PCMs prevent leakage, reduce the supercooling effect and minimize recalescence problems of the PCM. The differential scanning calorimetry (DSC) results show that perlite composite (ExPP) has the highest latent heat of melting and freezing values of (141.6 J/g and 143.7 J/g) respectively, compared with oil ash (OAP) and scoria (SCP) composites. Moreover, ExPP has the highest impregnation ratio, energy storage efficiency, and energy storage capacity compared with OAP and SCP. However, OAP and SCP have higher thermal conductivity values compared to ExPP composites which accelerate the thermal storage response in the composite. These results were confirmed with DSC, and the characteristic of the PCMs was investigated by using XRD and FE-SEM techniques.Keywords: expanded perlite, oil ash, scoria, energy storage material
Procedia PDF Downloads 907703 A Systamatic Review on Experimental, FEM Analysis and Simulation of Metal Spinning Process
Authors: Amol M. Jadhav, Sharad S. Chudhari, S. S. Khedkar
Abstract:
This review presents a through survey of research paper work on the experimental analysis, FEM Analysis & simulation of the metal spinning process. In this literature survey all the papers being taken from Elsevier publication and most of the from journal of material processing technology. In a last two decade or so, metal spinning process gradually used as chip less formation for the production of engineering component in a small to medium batch quantities. The review aims to provide include into the experimentation, FEM analysis of various components, simulation of metal spinning process and act as guide for research working on metal spinning processes. The review of existing work has several gaps in current knowledge of metal spinning processes. The evaluation of experiment is thickness strain, the spinning force, the twisting angle, the surface roughness of the conventional & shear metal spinning process; the evaluation of FEM of metal spinning to path definition with sufficient fine mesh to capture behavior of work piece; The evaluation of feed rate of roller, direction of roller,& type of roller stimulated. The metal spinning process has the more flexible to produce a wider range of product shape & to form more challenge material.Keywords: metal spinning, FEM analysis, simulation of metal spinning, mechanical engineering
Procedia PDF Downloads 3877702 Investigate and Control Thermal Spectra in Nanostructures and 2D Van der Waals Materials
Authors: Joon Sang Kang, Ming Ke, Yongjie Hu
Abstract:
Controlling heat transfer and thermal properties of materials is important to many fields such as energy efficiency and thermal management of integrated circuits. Significant progress over the past decade has been made to improve material performance through structuring at the nanoscale, however a clear relationship between structure dimensions, interfaces, and thermal properties remains to be established. The main challenge comes from the unknown intrinsic spectral contribution from different phonons. Here, we describe our current progress on quantifying and controlling thermal spectra based on our recently developed technical approach using ultrafast optical spectroscopy. Our work brings further the promise of rational material design to achieve high performance through a synergistic experimental-modeling approach. This approach can be broadly applicable to a wide range of materials and energy systems. In particular, we demonstrate in-situ characterization and tunable thermal properties of 2D van der waals materials through ionic intercalations. The significant impacts of this research in improving the efficiency of thermal energy conversion and management will also be illustrated.Keywords: energy, mean free path, nanoscale heat transfer, nanostructure, phonons, TDTR, thermoelectrics, 2D materials
Procedia PDF Downloads 2887701 Lanthanum Fluoride with Embedded Silicon Nanocrystals: A Novel Material for Future Electronic Devices
Authors: Golam Saklayen, Sheikh Rashel al Ahmed, Ferdous Rahman, Ismail Abu Bakar
Abstract:
Investigation on Lanthanum Fluoride LaF3 layer embedding Silicon Nanocrystals (Si-NCs) fabricated using a novel one-step chemical method has been reported in this presentation. Application of this material has been tested for low-voltage operating non-volatile memory and Schottkey-junction solar cell. Colloidal solution of Si-NCs in hydrofluoric acid (HF) was prepared from meso-porous silicon by ultrasonic vibration (sonication). This solution prevents the Si-NCs to be oxidized. On a silicon (Si) substrate, LaCl3 solution in HCl is allowed to react with the colloidal solution of prepared Si-NCs. Since this solution contains HF, LaCl3 reacts with HF and produces LaF3 crystals that deposits on the silicon substrate as a layer embedding Si-NCs. This a novel single step chemical way of depositing LaF3 insulating layer embedding Si-NCs. The X-Ray diffraction of the deposited layer shows a polycrystalline LaF3 deposition on silicon. A non-stoichiometric LaF3 layer embedding Si-NCs was found by EDX analysis. The presence of Si-NCs was confirmed by SEM. FTIR spectroscopy of the deposited LaF3 powder also confirmed the presence of Si-NCs. The size of Si-NCs was found to be inversely proportional to the ultrasonic power. After depositing proper contacts on the back of Si and LaF3, the devices have been tested as a non-volatile memory and solar cell. A memory window of 525 mV was obtained at a programming and erasing bias of 2V. The LaF3 films with Si NCs showed strong absorption and was also found to decrease optical transmittance than pure LaF3 film of same thickness. The I-V characteristics of the films showed a dependency on the incident light intensity where current changed under various light illumination. Experimental results show a lot of promise for Si-NCs-embedded LaF3 layer to be used as an insulating layer in MIS devices as well as an photoactive material in Schottkey junction solar cells.Keywords: silicon nanocrystals (Si NCs), LaF3, colloidal solution, Schottky junction solar cell
Procedia PDF Downloads 3927700 Promoting Affordable Housing Public-Private Partnerships (PPPs) in Nigeria: Addressing Ethical Concerns in Construction and Exploring Solutions
Authors: Shem Ikoojo Ayegba, Ye Qi
Abstract:
Public-private partnerships (PPPs) can potentially be a transformative mechanism for advancing affordable housing in Nigeria., considering the current housing deficit between 17 – 24 million. Nevertheless, their effectiveness is marred by persistent unethical practices such as corruption and the utilization of subpar materials. Through a comprehensive mixed-methods approach, this study delves into the ethical quandaries within Nigerian housing construction and their cascading effects on the success of PPPs. Semi-structured interviews encompassing seasoned construction professionals and an in-depth content analysis of ongoing housing policies and projects in Nigeria reveal a culture of corruption across the value chain. This malaise is exacerbated by glaring deficiencies in oversight and a lack of transparent practices. A robust statistical survey involving diverse professionals, including engineers, architects, and project managers, echoes these findings, emphasizing that a frail institutional framework facilitates the persistence of substandard material use, professional negligence, and rampant bribery. Such compromised construction standards place residents in potential jeopardy and impede the achievement of broader sustainability objectives. This study propounds a suite of policy interventions to pave the way for thriving affordable housing PPPs: initiating transparent bidding processes, establishing non-negotiable quality benchmarks for construction materials, and incorporating independent third-party audits throughout the building phase. Furthermore, cultivating a culture of professional integrity through targeted ethics training for all construction personnel is imperative. This research furnishes pragmatic strategies that can radically enhance the potency of housing PPPs, thereby ensuring safe, durable, and affordable housing solutions for Nigeria's underserved populace.Keywords: public-private partnerships, affordable housing, unethical practicies, housing policies, construction ethics
Procedia PDF Downloads 797699 Design and Synthesis of Fully Benzoxazine-Based Porous Organic Polymer Through Sonogashira Coupling Reaction for CO₂ Capture and Energy Storage Application
Authors: Mohsin Ejaz, Shiao-Wei Kuo
Abstract:
The growing production and exploitation of fossil fuels have placed human society in serious environmental issues. As a result, it's critical to design efficient and eco-friendly energy production and storage techniques. Porous organic polymers (POPs) are multi-dimensional porous network materials developed through the formation of covalent bonds between different organic building blocks that possess distinct geometries and topologies. POPs have tunable porosities and high surface area making them a good candidate for an effective electrode material in energy storage applications. Herein, we prepared a fully benzoxazine-based porous organic polymers (TPA–DHTP–BZ POP) through sonogashira coupling of dihydroxyterephthalaldehyde (DHPT) and triphenylamine (TPA) containing benzoxazine (BZ) monomers. Firstly, both BZ monomers (TPA-BZ-Br and DHTP-BZ-Ea) were synthesized by three steps, including Schiff base, reduction, and mannich condensation reaction. Finally, the TPA–DHTP–BZ POP was prepared through the sonogashira coupling reaction of brominated monomer (TPA-BZ-Br) and ethynyl monomer (DHTP-BZ-Ea). Fourier transform infrared (FTIR) and solid-state nuclear magnetic resonance (NMR) spectroscopy confirmed the successful synthesis of monomers as well as POP. The porosity of TPA–DHTP–BZ POP was investigated by the N₂ absorption technique and showed a Brunauer–Emmett–Teller (BET) surface area of 196 m² g−¹, pore size 2.13 nm and pore volume of 0.54 cm³ g−¹, respectively. The TPA–DHTP–BZ POP experienced thermal ring-opening polymerization, resulting in poly (TPA–DHTP–BZ) POP having strong inter and intramolecular hydrogen bonds formed by phenolic groups and Mannich bridges, thereby enhancing CO₂ capture and supercapacitive performance. The poly(TPA–DHTP–BZ) POP demonstrated a remarkable CO₂ capture of 3.28 mmol g−¹ and a specific capacitance of 67 F g−¹ at 0.5 A g−¹. Thus, poly(TPA–DHTP–BZ) POP could potentially be used for energy storage and CO₂ capture applications.Keywords: porous organic polymer, benzoxazine, sonogashira coupling, CO₂, supercapacitor
Procedia PDF Downloads 737698 Evaluation on Mechanical Stabilities of Clay-Sand Mixtures Used as Engineered Barrier for Radioactive Waste Disposal
Authors: Ahmet E. Osmanlioglu
Abstract:
In this study, natural bentonite was used as natural clay material and samples were taken from the Kalecik district in Ankara. In this research, bentonite is the subject of an analysis from standpoint of assessing the basic properties of engineered barriers with respect to the buffer material. Bentonite and sand mixtures were prepared for tests. Some of clay minerals give relatively higher hydraulic conductivity and lower swelling pressure. Generally, hydraulic conductivity of these type clays is lower than <10-12 m/s. The hydraulic properties of clay-sand mixtures are evaluated to design engineered barrier specifications. Hydraulic conductivities of bentonite-sand mixture were found in the range of 1.2x10-10 to 9.3x10-10 m/s. Optimum B/S mixture ratio was determined as 35% in terms of hydraulic conductivity and mechanical stability. At the second stage of this study, all samples were compacted into cylindrical shape molds (diameter: 50 mm and length: 120 mm). The strength properties of compacted mixtures were better than the compacted bentonite. In addition, the larger content of the quartz sand in the mixture has the greater thermal conductivity.Keywords: engineered barriers, mechanical stability, clay, nuclear waste disposal
Procedia PDF Downloads 3857697 Utilization of Nipa Palm Fibers (Nypa fruticans) and Asian Green Mussels Shells (Perna viridis) as an Additive Material in Making a Fiber-Reinforced Concrete
Authors: Billy Angel B. Bayot, Hubert Clyde Z. Guillermo, Daniela Eve Margaret S. Olano, Lian Angeli Kaye E. Suarez
Abstract:
A utilization of Nipa palm fibers (Nypa fruticans) and Asian green mussel shells (Perna viridis) as additive materials in making fiber-reinforced concrete was carried out. The researchers collected Asian green mussel shells and Nipa palm fibers as additive materials in the production of fiber-reinforced concrete and were used to make 3 Setups containing 20g, 15g, and 10g of Nipa palm fiber varying to 10g, 20g, 30g of Asian green mussel shell powder and a traditional concrete with respect to curing period 7, 14, and 28 days. The concrete blocks were delivered to the UP Institute of Building Materials and Structures Laboratory (CoMSLab) following each curing test in order to evaluate their compressive strength. Researchers employed a Two-Way Analysis of Variance (ANOVA) and determined that curing days, concrete mixture, and the combined curing days with concrete have an effect on the compressive strength of concrete. ANOVA results indicating significant differences had been subjected to post hoc analysis using Tukey's HSD. These results then yielded the comparison of each curing time and different concrete mixtures with traditional concrete, which comes to the conclusion that a longer curing period leads to a higher compressive strength and Setup 3 (30g Asian green mussel shell with 10g Nipa palm fiber) has the larger mean compressive strength, making it the best proportion among the fiber-reinforced concrete mixtures and the only proportion that has significant effect to traditional one. As a result, the study concludes that certain curing times and concrete mix proportions of Asian green mussel shell and Nipa palm fiber are critical determinants in determining concrete compressive strength.Keywords: Asian green mussel shells (Perna viridis), Nipa palm fibers (Nypa fruticans), additives, fiber-reinforced concrete
Procedia PDF Downloads 637696 Analysis of Coloring Styles of Brazilian Urban Heritage
Authors: Natalia Naoumova
Abstract:
Facing changes and continuous growth of the contemporary cities, along with the globalization effects that accelerate cultural dissolution, the maintenance of cultural authenticity, which is implicit in historical areas as a part of cultural diversity, can be considered one of the key elements of a sustainable society. This article focuses on the polychromy of buildings in a historical context as an important feature of urban settings. It analyses the coloring of Brazilian urban heritage, characterized by the study of historical districts in Pelotas and Piratini, located in the State of Rio Grande do Sul, Brazil. The objective is to reveal the coloring characteristics of different historical periods, determine the chromatic typologies of the corresponding building styles, and clarify the connection between the historical chromatic aspects and their relationship with the contemporary urban identity. Architectural style data were collected by different techniques such as stratigraphic prospects of buildings, survey of historical records and descriptions, analysis of images and study of projects with colored facades kept in historical archives. Three groups of characteristics were considered in searching for working criteria in the formation of chromatic model typologies: 1) coloring palette; 2) morphology of the facade, and 3) their relationship. The performed analysis shows the formation of the urban chromatic image of the historical center as a continuous and dynamic process with the development of constant chromatic resources. It establishes that the changes in the formal language of subsequent historical periods lead to the changes in the chromatic schemes, providing a different reading of the facades both in terms of formal interpretation and symbolic meaning.Keywords: building style, historic colors, urban heritage, urban polychromy
Procedia PDF Downloads 1427695 Assessment for the Backfill Using the Run of the Mine Tailings and Portland Cement
Authors: Javad Someehneshin, Weizhou Quan, Abdelsalam Abugharara, Stephen Butt
Abstract:
Narrow vein mining (NVM) is exploiting very thin but valuable ore bodies that are uneconomical to extract by conventional mining methods. NVM applies the technique of Sustainable Mining by Drilling (SMD). The SMD method is used to mine stranded, steeply dipping ore veins, which are too small or isolated to mine economically using conventional methods since the dilution is minimized. This novel mining technique uses drilling rigs to extract the ore through directional drilling surgically. This paper is focusing on utilizing the run of the mine tailings and Portland cement as backfill material to support the hanging wall for providing safe mine operation. Cemented paste backfill (CPB) is designed by mixing waste tailings, water, and cement of the precise percentage for optimal outcomes. It is a non-homogenous material that contains 70-85% solids. Usually, a hydraulic binder is added to the mixture to increase the strength of the CPB. The binder fraction mostly accounts for 2–10% of the total weight. In the mining industry, CPB has been improved and expanded gradually because it provides safety and support for the mines. Furthermore, CPB helps manage the waste tailings in an economical method and plays a significant role in environmental protection.Keywords: backfilling, cement backfill, tailings, Portland cement
Procedia PDF Downloads 1387694 Utilization of Aluminium Dross as a Main Raw Material for Synthesize the Geopolymers via Mechanochemistry Method
Authors: Pimchanok Puksisuwan, Pitak Laorattanakul, Benya Cherdhirunkorn
Abstract:
The use of aluminium dross as a raw material for geopolymer synthesis via mechanochemistry method was studied. The geopolymers were prepared using aluminium dross from secondary aluminium industry, fly ash from a biomass power plant and liquid alkaline activators, which is a mixture of sodium silicate solution (Na2SiO3) and sodium hydroxide solution (NaOH) (Na2SiO3/NaOH ratio 4:1, 3:1 and 2:1). Aluminium dross consists mostly of alumina (Al2O3), silicon oxide (SiO2) and aluminium nitride (AlN). The raw materials were mixed and milled using the high energy ball milling method for 5, 10 and 15 minutes in order to reduce the particle size. The milled powders were uniaxially pressed into a cylinder die with the pressure of 2200 psi. The cylinder samples were cured in the sealed plastic bags for 3, 7 and 14 days at the room temperature and 60°C for 24 hour. The mechanical property of geopolymers was investigated. In addition, scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis were carried out in order to study the microstructure and phase structures of the geopolymers, respectively. The results showed that aluminium dross could enhance the mechanical property of geopolymers product by mechanochemistry method and meet the TISI requirements.Keywords: aluminium dross, fly ash, geopolymer, mechanochemistry
Procedia PDF Downloads 2537693 A Computational Analysis of Gas Jet Flow Effects on Liquid Aspiration in the Collison Nebulizer
Authors: James Q. Feng
Abstract:
Pneumatic nebulizers (as variations based on the Collison nebulizer) have been widely used for producing fine aerosol droplets from a liquid material. As qualitatively described by many authors, the basic working principle of those nebulizers involves utilization of the negative pressure associated with an expanding gas jet to syphon liquid into the jet stream, then to blow and shear into liquid sheets, filaments, and eventually droplets. But detailed quantitative analysis based on fluid mechanics theory has been lacking in the literature. The purpose of present work is to investigate the nature of negative pressure distribution associated with compressible gas jet flow in the Collison nebulizer by a computational fluid dynamics (CFD) analysis, using an OpenFOAM® compressible flow solver. The value of the negative pressure associated with a gas jet flow is examined by varying geometric parameters of the jet expansion channel adjacent to the jet orifice outlet. Such an analysis can provide valuable insights into fundamental mechanisms in liquid aspiration process, helpful for effective design of the pneumatic atomizer in the Aerosol Jet® direct-write system for micro-feature, high-aspect-ratio material deposition in additive manufacturing.Keywords: collison nebulizer, compressible gas jet flow, liquid aspiration, pneumatic atomization
Procedia PDF Downloads 1807692 Official Seals on the Russian-Qing Treaties: Material Manifestations and Visual Enunciations
Authors: Ning Chia
Abstract:
Each of the three different language texts (Manchu, Russian, and Latin) of the 1689 Treaty of Nerchinsk bore official seals from Imperial Russia and Qing China. These seals have received no academic attention, yet they can reveal a site of a layered and shared material, cultural, political, and diplomatic world of the time in Eastern Eurasia. The very different seal selections from both empires while ratifying the Treaty of Beijing in 1860 have obtained no scholarly advertency either; they can also explicate a tremendously changed relationship with visual and material manifestation. Exploring primary sources in Manchu, Russian, and Chinese languages as well as the images of the visual seals, this study investigates the reasons and purposes of utilizing official seals for the treaty agreement. A refreshed understanding of Russian-Qing diplomacy will be developed by pursuing the following aspects: (i) Analyzing the iconographic meanings of each seal insignia and unearthing a competitive, yet symbols-delivered and seal-generated, 'dialogue' between the two empires (ii) Contextualizing treaty seals within the historical seal cultures, and discovering how domestic seal system in each empire’s political institution developed into treaty-defined bilateral relations (iii) Expounding the seal confiding in each empire’s daily governing routines, and annotating the trust in the seal as a quested promise from the opponent negotiator to fulfill the treaty terms (iv) Contrasting the two seal traditions along two civilization-lines, Eastern vs. Western, and dissecting how the two styles of seal emblems affected the cross-cultural understanding or misunderstanding between the two empires (v) Comprehending the history-making events from the substantial resources such as the treaty seals, and grasping why the seals for the two treaties, so different in both visual design and symbolic value, were chosen in the two relationship eras (vi) Correlating the materialized seal 'expression' and the imperial worldviews based on each empire’s national/or power identity, and probing the seal-represented 'rule under the Heaven' assumption of China and Russian rising role in 'European-American imperialism … centered on East Asia' (Victor Shmagin, 2020). In conclusion, the impact of official seals on diplomatic treaties needs profound knowledge in seal history, insignia culture, and emblem belief to be able to comprehend. The official seals in both Imperial Russia and Qing China belonged to a particular statecraft art in a specific material and visual form. Once utilized in diplomatic treaties, the meticulously decorated and politically institutionalized seals were transformed from the determinant means for domestic administration and social control into the markers of an empire’s sovereign authority. Overlooked in historical practice, the insignia seal created a wire of 'visual contest' between the two rival powers. Through this material lens, the scholarly knowledge of the Russian-Qing diplomatic relationship will be significantly upgraded. Connecting Russian studies, Qing/Chinese studies, and Eurasian studies, this study also ties material culture, political culture, and diplomatic culture together. It promotes the study of official seals and emblem symbols in worldwide diplomatic history.Keywords: Russia-Qing diplomatic relation, Treaty of Beijing (1860), Treaty of Nerchinsk (1689), Treaty seals
Procedia PDF Downloads 2077691 Framing a Turkish Campus Sustainability Indicator Set
Authors: Cansu Tari, Ute Poerschke
Abstract:
Sustainable campus design and planning in Higher Education requires an entire action plan and coordination of physical, educational, and social systems. Many institutions in the world are defining their sustainable development path and some are following existing green building and sustainable campus rating/ranking systems, guidelines. In the context of higher education, Turkish universities have limited academic, social and financial support related to sustainable living, building, and campus studies. While some research has been conducted in the last 60 years by farsighted academics, most of these works are based on individuals’ or small organizations’ own interests and efforts, and they are not known enough by the population of universities and possible prospective investors. Regarding the recent fast and uncontrolled growth in the Turkish Higher Education environment, setting a campus sustainability indicator set is a necessity for sustainable development of universities. The main objective of this paper is to specify the applicable sustainability indicators in the national context of Turkey, and propose a model guideline for sustainable Turkish university campuses. The analysis of Turkish legislation on environmental issues, special conditions of Turkish Higher Education system, and Turkey’s environmental risks and challenges set the backbone of the study and distinguish the set of indicators from generalized guidelines. Finally, the paper outlines some concrete suggestions for Turkish Universities to integrate sustainability efforts in their regional context. It will be useful for campus sustainability managers and planners, interested in developing action plans in their national and regional scope.Keywords: campus sustainability, sustainability indicators, Turkish universities, national campus sustainability action plan
Procedia PDF Downloads 2587690 Identification of High-Rise Buildings Using Object Based Classification and Shadow Extraction Techniques
Authors: Subham Kharel, Sudha Ravindranath, A. Vidya, B. Chandrasekaran, K. Ganesha Raj, T. Shesadri
Abstract:
Digitization of urban features is a tedious and time-consuming process when done manually. In addition to this problem, Indian cities have complex habitat patterns and convoluted clustering patterns, which make it even more difficult to map features. This paper makes an attempt to classify urban objects in the satellite image using object-oriented classification techniques in which various classes such as vegetation, water bodies, buildings, and shadows adjacent to the buildings were mapped semi-automatically. Building layer obtained as a result of object-oriented classification along with already available building layers was used. The main focus, however, lay in the extraction of high-rise buildings using spatial technology, digital image processing, and modeling, which would otherwise be a very difficult task to carry out manually. Results indicated a considerable rise in the total number of buildings in the city. High-rise buildings were successfully mapped using satellite imagery, spatial technology along with logical reasoning and mathematical considerations. The results clearly depict the ability of Remote Sensing and GIS to solve complex problems in urban scenarios like studying urban sprawl and identification of more complex features in an urban area like high-rise buildings and multi-dwelling units. Object-Oriented Technique has been proven to be effective and has yielded an overall efficiency of 80 percent in the classification of high-rise buildings.Keywords: object oriented classification, shadow extraction, high-rise buildings, satellite imagery, spatial technology
Procedia PDF Downloads 1557689 From Modelled Design to Reality through Material and Machinery Lab and Field Tests: Porous Concrete Carparks at the Wanda Metropolitano Stadium in Madrid
Authors: Manuel de Pazos-Liano, Manuel Cifuentes-Antonio, Juan Fisac-Gozalo, Sara Perales-Momparler, Carlos Martinez-Montero
Abstract:
The first-ever game in the Wanda Metropolitano Stadium, the new home of the Club Atletico de Madrid, was played on September 16, 2017, thanks to the work of a multidisciplinary team that made it possible to combine urban development with sustainability goals. The new football ground sits on a 1.2 km² land owned by the city of Madrid. Its construction has dramatically increased the sealed area of the site (transforming the runoff coefficient from 0.35 to 0.9), and the surrounding sewer network has no capacity for that extra flow. As an alternative to enlarge the existing 2.5 m diameter pipes, it was decided to detain runoff on site by means of an integrated and durable infrastructure that would not blow up the construction cost nor represent a burden on the municipality’s maintenance tasks. Instead of the more conventional option of building a large concrete detention tank, the decision was taken on the use of pervious pavement on the 3013 car parking spaces for sub-surface water storage, a solution aligned with the city water ordinance and the Madrid + Natural project. Making the idea a reality, in only five months and during the summer season (which forced to pour the porous concrete only overnight), was a challenge never faced before in Spain, that required of innovation both at the material as well as the machinery side. The process consisted on: a) defining the characteristics required for the porous concrete (compressive strength of 15 N/mm2 and 20% voids); b) testing of different porous concrete dosages at the construction company laboratory; c) stablishing the cross section in order to provide structural strength and sufficient water detention capacity (20 cm porous concrete over a 5 cm 5/10 gravel, that sits on a 50 cm coarse 40/50 aggregate sub-base separated by a virgin fiber polypropylene geotextile fabric); d) hydraulic computer modelling (using the Full Hydrograph Method based on the Wallingford Procedure) to estimate design peak flows decrease (an average of 69% at the three car parking lots); e) use of a variety of machinery for the application of the porous concrete to achieve both structural strength and permeable surface (including an inverse rotating rolling imported from USA, and the so-called CMI, a sliding concrete paver used in the construction of motorways with rigid pavements); f) full-scale pilots and final construction testing by an accredited laboratory (pavement compressive strength average value of 15 N/mm2 and 0,0032 m/s permeability). The continuous testing and innovating construction process explained in detail within this article, allowed for a growing performance with time, finally proving the use of the CMI valid also for large porous car park applications. All this process resulted in a successful story that converts the Wanda Metropolitano Stadium into a great demonstration site that will help the application of the Spanish Royal Decree 638/2016 (it also counts with rainwater harvesting for grass irrigation).Keywords: construction machinery, permeable carpark, porous concrete, SUDS, sustainable develpoment
Procedia PDF Downloads 1447688 Memristor-A Promising Candidate for Neural Circuits in Neuromorphic Computing Systems
Authors: Juhi Faridi, Mohd. Ajmal Kafeel
Abstract:
The advancements in the field of Artificial Intelligence (AI) and technology has led to an evolution of an intelligent era. Neural networks, having the computational power and learning ability similar to the brain is one of the key AI technologies. Neuromorphic computing system (NCS) consists of the synaptic device, neuronal circuit, and neuromorphic architecture. Memristor are a promising candidate for neuromorphic computing systems, but when it comes to neuromorphic computing, the conductance behavior of the synaptic memristor or neuronal memristor needs to be studied thoroughly in order to fathom the neuroscience or computer science. Furthermore, there is a need of more simulation work for utilizing the existing device properties and providing guidance to the development of future devices for different performance requirements. Hence, development of NCS needs more simulation work to make use of existing device properties. This work aims to provide an insight to build neuronal circuits using memristors to achieve a Memristor based NCS. Here we throw a light on the research conducted in the field of memristors for building analog and digital circuits in order to motivate the research in the field of NCS by building memristor based neural circuits for advanced AI applications. This literature is a step in the direction where we describe the various Key findings about memristors and its analog and digital circuits implemented over the years which can be further utilized in implementing the neuronal circuits in the NCS. This work aims to help the electronic circuit designers to understand how the research progressed in memristors and how these findings can be used in implementing the neuronal circuits meant for the recent progress in the NCS.Keywords: analog circuits, digital circuits, memristors, neuromorphic computing systems
Procedia PDF Downloads 1747687 Coupled Space and Time Homogenization of Viscoelastic-Viscoplastic Composites
Authors: Sarra Haouala, Issam Doghri
Abstract:
In this work, a multiscale computational strategy is proposed for the analysis of structures, which are described at a refined level both in space and in time. The proposal is applied to two-phase viscoelastic-viscoplastic (VE-VP) reinforced thermoplastics subjected to large numbers of cycles. The main aim is to predict the effective long time response while reducing the computational cost considerably. The proposed computational framework is a combination of the mean-field space homogenization based on the generalized incrementally affine formulation for VE-VP composites, and the asymptotic time homogenization approach for coupled isotropic VE-VP homogeneous solids under large numbers of cycles. The time homogenization method is based on the definition of micro and macro-chronological time scales, and on asymptotic expansions of the unknown variables. First, the original anisotropic VE-VP initial-boundary value problem of the composite material is decomposed into coupled micro-chronological (fast time scale) and macro-chronological (slow time-scale) problems. The former is purely VE, and solved once for each macro time step, whereas the latter problem is nonlinear and solved iteratively using fully implicit time integration. Second, mean-field space homogenization is used for both micro and macro-chronological problems to determine the micro and macro-chronological effective behavior of the composite material. The response of the matrix material is VE-VP with J2 flow theory assuming small strains. The formulation exploits the return-mapping algorithm for the J2 model, with its two steps: viscoelastic predictor and plastic corrections. The proposal is implemented for an extended Mori-Tanaka scheme, and verified against finite element simulations of representative volume elements, for a number of polymer composite materials subjected to large numbers of cycles.Keywords: asymptotic expansions, cyclic loadings, inclusion-reinforced thermoplastics, mean-field homogenization, time homogenization
Procedia PDF Downloads 3697686 First Principls Study of Structural, Electronic, Magnetic and Optical Properties of SiNi₂O₄ Spinel Oxide
Authors: Karkour Selma
Abstract:
We conducted first principles full potential calculations using the Wien2k code to explore the structural, electronic, magnetic, and optical properties of SiNi₂O₄, a cubic normal spinel oxide. Our calculations, based on the GGA-PBEsol of the generalized gradient approximation, revealed several key findings. The spinel oxides exhibited a stable cubic structure in the ferromagnetic phase and showed 100% spin polarization. We determined the equilibrium lattice constant and internal parameter values. In terms of the electronic properties, we observed a direct bandgap of 2.68 eV for the spin-up configuration, while the spin-down configuration exhibited an indirect bandgap of 0.82 eV. Additionally, we calculated the total density of states and partial densities for each atom, finding a magnetic moment spin density of states of 8.0 μB per formula unit. The optical properties have been calculated. The real, Ԑ₁(ω) and the imaginary, Ԑ₂(ω) parts of the complex dielectric constants, refractivity, reflection and energy loss when light scattered from the material. The absorption region spanned from 1.5 eV to 14 eV, with significant intensity. The calculated results confirm the suitability of this material for optical and spintronic devices application.Keywords: DFT, spintronic, GGA, spinel
Procedia PDF Downloads 767685 Reduction of Biofilm Formation in Closed Circuit Cooling Towers
Authors: Irfan Turetgen
Abstract:
Closed-circuit cooling towers are cooling units that operate according to the indirect cooling principle. Unlike the open-loop cooling tower, the filler material includes a closed-loop water-operated heat exchanger. The main purpose of this heat exchanger is to prevent the cooled process water from contacting with the external environment. In order to ensure that the hot water is cooled, the water is cooled by the air flow and the circulation water of the tower as it passes through the pipe. They are now more commonly used than open loop cooling towers that provide cooling with plastic filling material. As with all surfaces in contact with water, there is a biofilm formation on the outer surface of the pipe. Although biofilm has been studied very well on plastic surfaces in open loop cooling towers, studies on biofilm layer formed on the heat exchangers of the closed circuit tower have not been found. In the recent study, natural biofilm formation was observed on the heat exchangers of the closed loop tower for 6 months. At the same time, nano-silica coating, which is known to reduce the formation of the biofilm layer, a comparison was made between the two different surfaces in terms of biofilm formation potential. Test surfaces were placed into biofilm reactor along with the untreated control coupons up to 6-months period for biofilm maturation. Natural bacterial communities were monitored to analyze the impact to mimic the real-life conditions. Surfaces were monthly analyzed in situ for their microbial load using epifluorescence microscopy. Wettability is known to play a key role in biofilm formation on surfaces, because characteristics of surface properties affect the bacterial adhesion. Results showed that surface-conditioning with nano-silica significantly reduce (up to 90%) biofilm formation. Easy coating process is a facile and low-cost method to prepare hydrophobic surface without any kinds of expensive compounds or methods.Keywords: biofilms, cooling towers, fill material, nano silica
Procedia PDF Downloads 1297684 Comparative Performance Study of Steel Plate Shear Wall with Reinforced Concrete Shear Wall
Authors: Amit S. Chauhan, S. Mandal
Abstract:
The structural response of shear walls subjected to various types of loads is difficult to predict precisely. They are incorporated in buildings to resist lateral forces and support the gravity loads. The steel plate shear walls (SPSWs) are used as lateral load resisting systems for buildings and acts as an alternative to reinforced concrete shear walls (RCSWs). This paper compares the behavior of SPSW with the RCSW incorporated in a building frame having G+6 storey, located in Zone III, using the technique of Equivalent Static Method (ESM) as per Indian Standard Criteria For Earthquake Resistant Design of Structures IS 1893:2002. This paper intends to evaluate several parameters such as lateral displacement at tip, inter-storey drift, weight of steel and volume of concrete with the alteration of the shear wall with respect to different types viz., SPSW and RCSW. The strip model employed in this study is a widely accepted analytical tool for SPSW analysis. SPSW can be modelled as truss members by using a series of diagonal tension strips positioned at 45-degree angles. In this paper, by replacing the SPSWs with the tension strips, the G+6 building has been analyzed using STAAD.Pro V8i. Based on the present study, it can be concluded that structure with SPSWs is much better then structure with RCSWs.Keywords: equivalent static method, inter-storey drift, lateral displacement, Steel plate shear wall, strip model
Procedia PDF Downloads 2467683 Comparative Comparison (Cost-Benefit Analysis) of the Costs Caused by the Earthquake and Costs of Retrofitting Buildings in Iran
Authors: Iman Shabanzadeh
Abstract:
Earthquake is known as one of the most frequent natural hazards in Iran. Therefore, policy making to improve the strengthening of structures is one of the requirements of the approach to prevent and reduce the risk of the destructive effects of earthquakes. In order to choose the optimal policy in the face of earthquakes, this article tries to examine the cost of financial damages caused by earthquakes in the building sector and compare it with the costs of retrofitting. In this study, the results of adopting the scenario of "action after the earthquake" and the policy scenario of "strengthening structures before the earthquake" have been collected, calculated and finally analyzed by putting them together. Methodologically, data received from governorates and building retrofitting engineering companies have been used. The scope of the study is earthquakes occurred in the geographical area of Iran, and among them, eight earthquakes have been specifically studied: Miane, Ahar and Haris, Qator, Momor, Khorasan, Damghan and Shahroud, Gohran, Hormozgan and Ezgole. The main basis of the calculations is the data obtained from retrofitting companies regarding the cost per square meter of building retrofitting and the data of the governorate regarding the power of earthquake destruction, the realized costs for the reconstruction and construction of residential units. The estimated costs have been converted to the value of 2021 using the time value of money method to enable comparison and aggregation. The cost-benefit comparison of the two policies of action after the earthquake and retrofitting before the earthquake in the eight earthquakes investigated shows that the country has suffered five thousand billion Tomans of losses due to the lack of retrofitting of buildings against earthquakes. Based on the data of the Budget Law's of Iran, this figure was approximately twice the budget of the Ministry of Roads and Urban Development and five times the budget of the Islamic Revolution Housing Foundation in 2021. The results show that the policy of retrofitting structures before an earthquake is significantly more optimal than the competing scenario. The comparison of the two policy scenarios examined in this study shows that the policy of retrofitting buildings before an earthquake, on the one hand, prevents huge losses, and on the other hand, by increasing the number of earthquake-resistant houses, it reduces the amount of earthquake destruction. In addition to other positive effects of retrofitting, such as the reduction of mortality due to earthquake resistance of buildings and the reduction of other economic and social effects caused by earthquakes. These are things that can prove the cost-effectiveness of the policy scenario of "strengthening structures before earthquakes" in Iran.Keywords: disaster economy, earthquake economy, cost-benefit analysis, resilience
Procedia PDF Downloads 63