Search results for: energy conversion efficiency
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 13398

Search results for: energy conversion efficiency

7878 Improvement of Fixed Offshore Structures' Boat Landing Performance Using Practicable Design Criteria

Authors: A. Hamadelnil, Z. Razak, E. Matsoom

Abstract:

Boat landings on fixed offshore structure are designed to absorb the impact energy from the boats approaching the platform for crew transfer. As the size and speed of operating boats vary, the design and maintenance of the boat landings become more challenging. Different oil and gas operators adopting different design criteria for the boat landing design in the region of South East Asia. Rubber strip is used to increase the capacity of the boat landing in absorbing bigger impact energy. Recently, it has been reported that all the rubber strips peel off the boat landing frame within one to two years, and replacement is required to avoid puncturing of the boat’s hull by the exposed sharp edges and bolts used to secure the rubber strip. The capacity of the boat landing in absorbing the impact energy is reduced after the failure of the rubber strip and results in failure of the steel members. The replacement of the rubber strip is costly as it requires a diving spread. The objective of this study is to propose the most practicable criteria to be adopted by oil and gas operators in the design of the boat landings in the region of South East Asia to improve the performance of the boat landing and assure safe operation and cheaper maintenance. This study explores the current design and maintenance challenges of boat landing and compares between the criteria adopted by different operators. In addition, this study explains the reasons behind the denting of many of the boat landing. It also evaluates the effect of grout and rubber strip in the capacity of the boat landing and jacket legs and highlight. Boat landing model and analysis using USFOS and SACS software are carried out and presented in this study considering different design criteria. This study proposes the most practicable criteria to be used in designing the boat landing in South East Asia region to save cost and achieve better performance, safe operation and less cost and maintenance.

Keywords: boat landing, grout, plastic hinge, rubber strip

Procedia PDF Downloads 275
7877 Compact Dual-band 4-MIMO Antenna Elements for 5G Mobile Applications

Authors: Fayad Ghawbar

Abstract:

The significance of the Multiple Input Multiple Output (MIMO) system in the 5G wireless communication system is essential to enhance channel capacity and provide a high data rate resulting in a need for dual-polarization in vertical and horizontal. Furthermore, size reduction is critical in a MIMO system to deploy more antenna elements requiring a compact, low-profile design. A compact dual-band 4-MIMO antenna system has been presented in this paper with pattern and polarization diversity. The proposed single antenna structure has been designed using two antenna layers with a C shape in the front layer and a partial slot with a U-shaped cut in the ground to enhance isolation. The single antenna is printed on an FR4 dielectric substrate with an overall size of 18 mm×18 mm×1.6 mm. The 4-MIMO antenna elements were printed orthogonally on an FR4 substrate with a size dimension of 36 × 36 × 1.6 mm3 with zero edge-to-edge separation distance. The proposed compact 4-MIMO antenna elements resonate at 3.4-3.6 GHz and 4.8-5 GHz. The s-parameters measurement and simulation results agree, especially in the lower band with a slight frequency shift of the measurement results at the upper band due to fabrication imperfection. The proposed design shows isolation above -15 dB and -22 dB across the 4-MIMO elements. The MIMO diversity performance has been evaluated in terms of efficiency, ECC, DG, TARC, and CCL. The total and radiation efficiency were above 50 % across all parameters in both frequency bands. The ECC values were lower than 0.10, and the DG results were about 9.95 dB in all antenna elements. TARC results exhibited values lower than 0 dB with values lower than -25 dB in all MIMO elements at the dual-bands. Moreover, the channel capacity losses in the MIMO system were depicted using CCL with values lower than 0.4 Bits/s/Hz.

Keywords: compact antennas, MIMO antenna system, 5G communication, dual band, ECC, DG, TARC

Procedia PDF Downloads 132
7876 A Tunable Long-Cavity Passive Mode-Locked Fiber Laser Based on Nonlinear Amplifier Loop Mirror

Authors: Pinghe Wang

Abstract:

In this paper, we demonstrate a tunable long-cavity passive mode-locked fiber laser. The mode locker is a nonlinear amplifying loop mirror (NALM). The cavity frequency of the laser is 465 kHz because that 404m SMF is inserted in the cavity. A tunable bandpass filter with ~1nm 3dB bandwidth is inserted into the cavity to realize tunable mode locking. The passive mode-locked laser at a fixed wavelength is investigated in detail. The experimental results indicate that the laser operates in dissipative soliton resonance (DSR) region. When the pump power is 400mW, the laser generates the rectangular pulses with 10.58 ns pulse duration, 70.28nJ single-pulse energy. When the pump power is 400mW, the laser keeps stable mode locking status in the range from 1523.4nm to 1575nm. During the whole tuning range, the SNR, the pulse duration, the output power and single pulse energy have a little fluctuation because that the gain of the EDF changes with the wavelength.

Keywords: fiber laser, dissipative soliton resonance, mode locking, tunable

Procedia PDF Downloads 227
7875 A Study on Using Network Coding for Packet Transmissions in Wireless Sensor Networks

Authors: Rei-Heng Cheng, Wen-Pinn Fang

Abstract:

A wireless sensor network (WSN) is composed by a large number of sensors and one or a few base stations, where the sensor is responsible for detecting specific event information, which is sent back to the base station(s). However, how to save electricity consumption to extend the network lifetime is a problem that cannot be ignored in the wireless sensor networks. Since the sensor network is used to monitor a region or specific events, how the information can be reliably sent back to the base station is surly important. Network coding technique is often used to enhance the reliability of the network transmission. When a node needs to send out M data packets, it encodes these data with redundant data and sends out totally M + R packets. If the receiver can get any M packets out from these M + R packets, it can decode and get the original M data packets. To transmit redundant packets will certainly result in the excess energy consumption. This paper will explore relationship between the quality of wireless transmission and the number of redundant packets. Hopefully, each sensor can overhear the nearby transmissions, learn the wireless transmission quality around it, and dynamically determine the number of redundant packets used in network coding.

Keywords: energy consumption, network coding, transmission reliability, wireless sensor networks

Procedia PDF Downloads 377
7874 An Intelligent Prediction Method for Annular Pressure Driven by Mechanism and Data

Authors: Zhaopeng Zhu, Xianzhi Song, Gensheng Li, Shuo Zhu, Shiming Duan, Xuezhe Yao

Abstract:

Accurate calculation of wellbore pressure is of great significance to prevent wellbore risk during drilling. The traditional mechanism model needs a lot of iterative solving procedures in the calculation process, which reduces the calculation efficiency and is difficult to meet the demand of dynamic control of wellbore pressure. In recent years, many scholars have introduced artificial intelligence algorithms into wellbore pressure calculation, which significantly improves the calculation efficiency and accuracy of wellbore pressure. However, due to the ‘black box’ property of intelligent algorithm, the existing intelligent calculation model of wellbore pressure is difficult to play a role outside the scope of training data and overreacts to data noise, often resulting in abnormal calculation results. In this study, the multi-phase flow mechanism is embedded into the objective function of the neural network model as a constraint condition, and an intelligent prediction model of wellbore pressure under the constraint condition is established based on more than 400,000 sets of pressure measurement while drilling (MPD) data. The constraint of the multi-phase flow mechanism makes the prediction results of the neural network model more consistent with the distribution law of wellbore pressure, which overcomes the black-box attribute of the neural network model to some extent. The main performance is that the accuracy of the independent test data set is further improved, and the abnormal calculation values basically disappear. This method is a prediction method driven by MPD data and multi-phase flow mechanism, and it is the main way to predict wellbore pressure accurately and efficiently in the future.

Keywords: multiphase flow mechanism, pressure while drilling data, wellbore pressure, mechanism constraints, combined drive

Procedia PDF Downloads 162
7873 An Exploratory Study to Understand the Economic Opportunities from Climate Change

Authors: Sharvari Parikh

Abstract:

Climate change has always been looked upon as a threat. Increased use of fossil fuels, depletion of bio diversity, certain human activities, rising levels of Greenhouse Gas (GHG) emissions are the factors that have caused climate change. Climate change is creating new risks and aggravating the existing ones. The paper focuses on breaking the stereotypical perception of climate change and draws attention towards the constructive side of it. Researches around the world have concluded that climate change has provided us with many untapped opportunities. The next 15 years will be crucial, as it is in our hands whether we are able to grab these opportunities or just let the situation get worse. The world stands at a stage where we cannot think of making a choice between averting climate change and promoting growth and development. In fact, the solution to climate change itself has got economic opportunities. The data evidences from the paper show how we can create the opportunity to improve the lives of the world’s population at large through structural change which will promote environment friendly investments. Rising Investment in green energy and increased demand of climate friendly products has got ample of employment opportunities. Old technologies and machinery which are employed today lack efficiency and demand huge maintenance because of which we face high production cost. This can be drastically brought down by adaptation of Green technologies which are more accessible and affordable. Overall GDP of the world has been heavily affected in aggravating the problems arising out of increasing weather problems. Shifting to green economy can not only eliminate these costs but also build a sound economy. Accelerating the economy in direction of low-carbon future can lessen the burdens such as subsidies for fossil fuels, several public debts, unemployment, poverty, reduce healthcare expenses etc. It is clear that the world will be dragged into the ‘Darker phase’ if the current trends of fossil fuels and carbon are being consumed. Switching to Green economy is the only way in which we can lift the world from darker phase. Climate change has opened the gates for ‘Green and Clean economy’. It will also bring countries of the world together in achieving the common goal of Green Economy.

Keywords: climate change, economic opportunities, green economy, green technology

Procedia PDF Downloads 227
7872 Modern Seismic Design Approach for Buildings with Hysteretic Dampers

Authors: Vanessa A. Segovia, Sonia E. Ruiz

Abstract:

The use of energy dissipation systems for seismic applications has increased worldwide, thus it is necessary to develop practical and modern criteria for their optimal design. Here, a direct displacement-based seismic design approach for frame buildings with hysteretic energy dissipation systems (HEDS) is applied. The building is constituted by two individual structural systems consisting of: 1) A main elastic structural frame designed for service loads and 2) A secondary system, corresponding to the HEDS, that controls the effects of lateral loads. The procedure implies to control two design parameters: A) The stiffness ratio (α=K_frame/K_(total system)), and B) The strength ratio (γ= V_damper / V_(total system)). The proposed damage-controlled approach contributes to the design of a more sustainable and resilient building because the structural damage is concentrated on the HEDS. The reduction of the design displacement spectrum is done by means of a damping factor (recently published) for elastic structural systems with HEDS, located in Mexico City. Two limit states are verified: Serviceability and near collapse. Instead of the traditional trial-error approach, a procedure that allows the designer to establish the preliminary sizes of the structural elements of both systems is proposed. The design methodology is applied to an 8-story steel building with buckling restrained braces, located in soft soil of Mexico City. With the aim of choosing the optimal design parameters, a parametric study is developed considering different values of α and γ. The simplified methodology is for preliminary sizing, design, and evaluation of the effectiveness of HEDS, and it constitutes a modern and practical tool that enables the structural designer to select the best design parameters.

Keywords: damage-controlled buildings, direct displacement-based seismic design, optimal hysteretic energy dissipation systems, hysteretic dampers

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7871 Energy Saving in Handling the Air-Conditioning Latent-Load Using a Liquid Desiccant Air Conditioner: Parametric Experimental Analysis

Authors: Mustafa Jaradat

Abstract:

Reasonable energy saving for dehumidification is feasible with the use of desiccants. Desiccants are able to lower the humidity content in the air irrespective of the dew point temperature. In this paper, a tube bundle liquid desiccant air conditioner was experimentally designed and evaluated using lithium chloride as a desiccant. Several experiments were conducted to evaluate the influence of the inlet parameters on the dehumidifier performance. The results show a reduction in the relative humidity in the range of 17 to 46%, and the change in the humidity ratio was between 1.5 to 4.7 g/kg, depending on the inlet conditions. A water removal rate in the range between 0.54 and 1.67 kg/h was observed. The effects of air relative humidity and the desiccant flow rate on the dehumidifier’s performance were investigated. It was found that the moisture removal rate remarkably increased with increasing desiccant flow rate and air inlet humidity ratio. The dehumidifier effectiveness increased sharply with increasing desiccant flow rate. Also, it was found that the dehumidifier effectiveness slightly decreased with air humidity ratio.

Keywords: air conditioning, dehumidification, desiccant, lithium chloride, tube bundle

Procedia PDF Downloads 131
7870 Efficiency of a Molecularly Imprinted Polymer for Selective Removal of Chlorpyrifos from Water Samples

Authors: Oya A. Urucu, Aslı B. Çiğil, Hatice Birtane, Ece K. Yetimoğlu, Memet Vezir Kahraman

Abstract:

Chlorpyrifos is an organophosphorus pesticide which can be found in environmental water samples. The efficiency and reuse of a molecularly imprinted polymer (chlorpyrifos - MIP) were investigated for the selective removal of chlorpyrifos residues. MIP was prepared with UV curing thiol-ene polymerization technology by using multifunctional thiol and ene monomers. The thiol-ene curing reaction is a radical induced process, however unlike other photoinitiated polymerization processes, this polymerization process is a free-radical reaction that proceeds by a step-growth mechanism, involving two main steps; a free-radical addition followed by a chain transfer reaction. It assures a very rapidly formation of a uniform crosslinked network with low shrinkage, reduced oxygen inhibition during curing and excellent adhesion. In this study, thiol-ene based UV-curable polymeric materials were prepared by mixing pentaerythritol tetrakis(3-mercaptopropionate), glyoxal bis diallyl acetal, polyethylene glycol diacrylate (PEGDA) and photoinitiator. Chlorpyrifos was added at a definite ratio to the prepared formulation. Chemical structure and thermal properties were characterized by FTIR and thermogravimetric analysis (TGA), respectively. The pesticide analysis was performed by gas chromatography-mass spectrometry (GC-MS). The influences of some analytical parameters such as pH, sample volume, amounts of analyte concentration were studied for the quantitative recoveries of the analyte. The proposed MIP method was applied to the determination of chlorpyrifos in river and tap water samples. The use of the MIP provided a selective and easy solution for removing chlorpyrifos from the water.

Keywords: molecularly imprinted polymers, selective removal, thilol-ene, uv-curable polymer

Procedia PDF Downloads 287
7869 Analysis of Bio-Oil Produced by Pyrolysis of Coconut Shell

Authors: D. S. Fardhyanti, A. Damayanti

Abstract:

The utilization of biomass as a source of new and renewable energy is being carried out. One of the technologies to convert biomass as an energy source is pyrolysis which is converting biomass into more valuable products, such as bio-oil. Bio-oil is a liquid which is produced by steam condensation process from the pyrolysis of coconut shells. The composition of a coconut shell e.g. hemicellulose, cellulose and lignin will be oxidized to phenolic compounds as the main component of the bio-oil. The phenolic compounds in bio-oil are corrosive; they cause various difficulties in the combustion system because of a high viscosity, low calorific value, corrosiveness, and instability. Phenolic compounds are very valuable components which phenol has used as the main component for the manufacture of antiseptic, disinfectant (known as Lysol) and deodorizer. The experiments typically occurred at the atmospheric pressure in a pyrolysis reactor at temperatures ranging from 300 oC to 350 oC with a heating rate of 10 oC/min and a holding time of 1 hour at the pyrolysis temperature. The Gas Chromatography-Mass Spectroscopy (GC-MS) was used to analyze the bio-oil components. The obtained bio-oil has the viscosity of 1.46 cP, the density of 1.50 g/cm3, the calorific value of 16.9 MJ/kg, and the molecular weight of 1996.64. By GC-MS, the analysis of bio-oil showed that it contained phenol (40.01%), ethyl ester (37.60%), 2-methoxy-phenol (7.02%), furfural (5.45%), formic acid (4.02%), 1-hydroxy-2-butanone (3.89%), and 3-methyl-1,2-cyclopentanedione (2.01%).

Keywords: bio-oil, pyrolysis, coconut shell, phenol, gas chromatography-mass spectroscopy

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7868 Old Community Spatial Integration: Discussion on the Mechanism of Aging Space System Replacement

Authors: Wan-I Chen, Tsung-I Pai

Abstract:

Future the society aging of population will create the social problem has not had the good mechanism solution in the Asian country, especially in Taiwan. In the future ten year the people in Taiwan must facing the condition which is localization aging social problem. In this situation, how to use the spatial in eco way to development space use to solve the old age spatial demand is the way which might develop in the future Taiwan society. Over the next 10 years, taking care of the aging people will become part of the social problem of aging phenomenon. The research concentrate in the feasibility of spatial substitution, secondary use of spatial might solve out of spatial problem for aging people. In order to prove the space usable, the research required to review the project with the support system and infill system for space experiment, by using network grid way. That defined community level of space elements location relationship, make new definitions of space and return to cooperation. Research to innovation in the the appraisal space causes the possibility, by spatial replacement way solution on spatial insufficient suitable condition. To evaluation community spatial by using the support system and infill system in order to see possibilities of use in replacement inner space and modular architecture into housing. The study is discovering the solution on the Eco way to develop space use to figure out the old age spatial demand.

Keywords: sustainable use, space conversion, integration, replacement


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7867 Optimization of the Administration of Intravenous Medication by Reduction of the Residual Volume, Taking User-Friendliness, Cost Efficiency, and Safety into Account

Authors: A. Poukens, I. Sluyts, A. Krings, J. Swartenbroekx, D. Geeroms, J. Poukens

Abstract:

Introduction and Objectives: It has been known for many years that with the administration of intravenous medication, a rather significant part of the planned to be administered infusion solution, the residual volume ( the volume that remains in the IV line and or infusion bag), does not reach the patient and is wasted. This could possibly result in under dosage and diminished therapeutic effect. Despite the important impact on the patient, the reduction of residual volume lacks attention. An optimized and clearly stated protocol concerning the reduction of residual volume in an IV line is necessary for each hospital. As described in my Master’s thesis, acquiring the degree of Master in Hospital Pharmacy, administration of intravenous medication can be optimized by reduction of the residual volume. Herewith effectiveness, user-friendliness, cost efficiency and safety were taken into account. Material and Methods: By usage of a literature study and an online questionnaire sent out to all Flemish hospitals and hospitals in the Netherlands (province Limburg), current flush methods could be mapped out. In laboratory research, possible flush methods aiming to reduce the residual volume were measured. Furthermore, a self-developed experimental method to reduce the residual volume was added to the study. The current flush methods and the self-developed experimental method were compared to each other based on cost efficiency, user-friendliness and safety. Results: There is a major difference between the Flemish and the hospitals in the Netherlands (Province Limburg) concerning the approach and method of flushing IV lines after administration of intravenous medication. The residual volumes were measured and laboratory research showed that if flushing was done minimally 1-time equivalent to the residual volume, 95 percent of glucose would be flushed through. Based on the comparison, it became clear that flushing by use of a pre-filled syringe would be the most cost-efficient, user-friendly and safest method. According to laboratory research, the self-developed experimental method is feasible and has the advantage that the remaining fraction of the medication can be administered to the patient in unchanged concentration without dilution. Furthermore, this technique can be applied regardless of the level of the residual volume. Conclusion and Recommendations: It is recommendable to revise the current infusion systems and flushing methods in most hospitals. Aside from education of the hospital staff and alignment on a uniform substantiated protocol, an optimized and clear policy on the reduction of residual volume is necessary for each hospital. It is recommended to flush all IV lines with rinsing fluid with at least the equivalent volume of the residual volume. Further laboratory and clinical research for the self-developed experimental method are needed before this method can be implemented clinically in a broader setting.

Keywords: intravenous medication, infusion therapy, IV flushing, residual volume

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7866 The Response of the Accumulated Biomass and the Efficiency of Water Use in Five Varieties of Durum Wheat Lines under Water Stress

Authors: Fellah Sihem

Abstract:

The optimal use of soil moisture by culture, is related to the leaf area index, which stood in the cycle and its modulation according to the prevailing stress intensity. For a given stock of water in the soil, cultivar adapted and saving water is one that is no luxury consumption during the preanthesis. It modulates the leaf area index to regulate sweating in the degree of its water supply. In plants water saving, avoidance of dehydration is related to the reduction of water loss by cuticular and stomatal pathways. Muchow and Sinclair reported that the test of relative water content (TRE) is considered the best indicator of leaf water status. The search for indicators of the ability of the plant to make good use of the water, under water stress is a prerequisite for progress in improving performance under water stress. This experiment aims to characterize a set of durum wheat varieties, tested jars and vegetation under different levels of water stress to the surface of the leaf, relative water content, cell integrity, the accumulated biomass and efficiency of water use. The experiment was conducted during the 2005/2006 academic year, at the Agricultural Research Station of the Field Crop Institute of Setif, under semi-controlled conditions. Five genotypes of durum wheat (Triticum durum Desf) were evaluated for their ability to tolerate moderate and severe water stress. The results showed that geno types respond differently to water stress. Dry matter accumulation and growth rate varied among geno types and were significantly reduced. At severe water stress biomass accumulated by Boussalam was the least affected.

Keywords: water stress, triticum durum, biomass, cell membrane integrity, relative water content

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7865 Assessment of Hydrogen Demand for Different Technological Pathways to Decarbonise the Aviation Sector in Germany

Authors: Manish Khanra, Shashank Prabhu

Abstract:

The decarbonization of hard-to-abate sectors is currently high on the agenda in the EU and its member states, as these sectors have substantial shares in overall GHG emissions while it is facing serious challenges to decarbonize. In particular, the aviation sector accounts for 2.8% of global anthropogenic CO₂ emissions. These emissions are anticipated to grow dramatically unless immediate mitigating efforts are implemented. Hydrogen and its derivatives based on renewable electricity can have a key role in the transition towards CO₂-neutral flights. The substantial shares of energy carriers in the form of drop-in fuel, direct combustion and Hydrogen-to-Electric are promising in most scenarios towards 2050. For creating appropriate policies to ramp up the production and utilisation of hydrogen commodities in the German aviation sector, a detailed analysis of the spatial distribution of supply-demand sites is essential. The objective of this research work is to assess the demand for hydrogen-based alternative fuels in the German aviation sector to achieve the perceived goal of the ‘Net Zero’ scenario by 2050. Here, the analysis of the technological pathways for the production and utilisation of these fuels in various aircraft options is conducted for reaching mitigation targets. Our method is based on data-driven bottom-up assessment, considering production and demand sites and their spatial distribution. The resulting energy demand and its spatial distribution with consideration of technology diffusion lead to a possible transition pathway of the aviation sector to meet short-term and long-term mitigation targets. Additionally, to achieve mitigation targets in this sector, costs and policy aspects are discussed, which would support decision-makers from airline industries, policymakers and the producers of energy commodities.

Keywords: the aviation sector, hard-to-abate sectors, hydrogen demand, alternative fuels, technological pathways, data-driven approach

Procedia PDF Downloads 115
7864 Influence of Particulate Fractions on Air Quality for Four Major Congested Cities of India over a Period of Four Years from 2006-2009

Authors: I. Mukherjee, J. Ghose, T. Chakraborty, S. Chaudhury, R. Majumder

Abstract:

India is the second most populated nation in the world. With the Indian population hitting the 1.26 billion mark in the year 2014, there has been an unprecedented rise in power and energy requirements throughout the nation. This mammoth demand for energy, both at the industrial as well as at the domestic household level, as well as the increase in the usage of automobiles has led to a corresponding increase in the total tonnage of fuels being burnt every year. This, in turn, has led to an increase in the concentration of atmospheric pollutants over the years with enhanced particulate concentrations being reported for different parts of the country. Considering the adverseness of the particulates, the paper analyses the role of the particulates on the air quality of four major congested cities of the country namely, Kolkata (22034’ N, 88024’ E), Delhi (28038’N , 77012’ E), Bangalore (12058’ N , 77038’E) and Mumbai (18.9750° N, 72.8258° E) over a period of four years from 2006-2009. The fractional contribution of the finer fractions to the coarser one has been considered in the study in addition to the relative occurrences of the particulate fractions with respect to the other gaseous pollutants such as sulphur dioxide (SO2) and nitrogen oxides (NOX).

Keywords: air quality, particulates, yearly variation, relative occurrence, SO2, NOX

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7863 Development of Scenarios for Sustainable Next Generation Nuclear System

Authors: Muhammad Minhaj Khan, Jaemin Lee, Suhong Lee, Jinyoung Chung, Johoo Whang

Abstract:

The Republic of Korea has been facing strong storage crisis from nuclear waste generation as At Reactor (AR) temporary storage sites are about to reach saturation. Since the country is densely populated with a rate of 491.78 persons per square kilometer, Construction of High-level waste repository will not be a feasible option. In order to tackle the storage waste generation problem which is increasing at a rate of 350 tHM/Yr. and 380 tHM/Yr. in case of 20 PWRs and 4 PHWRs respectively, the study strongly focuses on the advancement of current nuclear power plants to GEN-IV sustainable and ecological nuclear systems by burning TRUs (Pu, MAs). First, Calculations has made to estimate the generation of SNF including Pu and MA from PWR and PHWR NPPS by using the IAEA code Nuclear Fuel Cycle Simulation System (NFCSS) for the period of 2016, 2030 (including the saturation period of each site from 2024~2028), 2089 and 2109 as the number of NPPS will increase due to high import cost of non-nuclear energy sources. 2ndly, in order to produce environmentally sustainable nuclear energy systems, 4 scenarios to burnout the Plutonium and MAs are analyzed with the concentration on burning of MA only, MA and Pu together by utilizing SFR, LFR and KALIMER-600 burner reactor after recycling the spent oxide fuel from PWR through pyro processing technology developed by Korea Atomic Energy Research Institute (KAERI) which shows promising and sustainable future benefits by minimizing the HLW generation with regard to waste amount, decay heat, and activity. Finally, With the concentration on front and back end fuel cycles for open and closed fuel cycles of PWR and Pyro-SFR respectively, an overall assessment has been made which evaluates the quantitative as well as economical combativeness of SFR metallic fuel against PWR once through nuclear fuel cycle.

Keywords: GEN IV nuclear fuel cycle, nuclear waste, waste sustainability, transmutation

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7862 Mechanical Performance of Sandwich Square Honeycomb Structure from Sugar Palm Fibre

Authors: Z. Ansari, M. R. M. Rejab, D. Bachtiar, J. P. Siregar

Abstract:

This study focus on the compression and tensile properties of new and recycle square honeycombs structure from sugar palm fibre (SPF) and polylactic acid (PLA) composite. The end data will determine the failure strength and energy absorption for both new and recycle composite. The control SPF specimens were fabricated from short fibre co-mingled with PLA by using a bra-blender set at 180°C and 50 rpm consecutively. The mixture of 30% fibre and 70% PLA were later on the hot press at 180°C into sheets with thickness 3mm consecutively before being assembled into a sandwich honeycomb structure. An INSTRON tensile machine and Abaqus 6.13 software were used for mechanical test and finite element simulation. The percentage of error from the simulation and experiment data was 9.20% and 9.17% for both new and recycled product. The small error of percentages was acceptable due to the nature of the simulation model to be assumed as a perfect model with no imperfect geometries. The energy absorption value from new to recycled product decrease from 312.86kJ to 282.10kJ. With this small decrements, it is still possible to implement a recycle SPF/PLA composite into everyday usages such as a car's interior or a small size furniture.

Keywords: failure modes, numerical modelling, polylactic acid, sugar palm fibres

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7861 Solar-Powered Adsorption Cooling System: A Case Study on the Climatic Conditions of Al Minya

Authors: El-Sadek H. Nour El-deen, K. Harby

Abstract:

Energy saving and environment friendly applications are turning out to be one of the most important topics nowadays. In this work, a simulation analysis using TRNSYS software has been carried out to study the benefit of employing a solar adsorption cooling system under the climatic conditions of Al-Minya city, Egypt. A theoretical model was carried out on a two bed adsorption cooling system employing granular activated carbon-HFC-404A as working pair. Temporal and averaged history of solar collector, adsorbent beds, evaporator and condenser has been shown. System performance in terms of daily average cooling capacity and average coefficient of performance around the year has been investigated. The results showed that maximum yearly average coefficient of performance (COP) and cooling capacity are about 0.26 and 8 kW respectively. The maximum value of the both average cooling capacity and COP cyclic is directly proportional to the maximum solar radiation. The system performance was found to be increased with the average ambient temperature. Finally, the proposed solar powered adsorption cooling systems can be used effectively under Al-Minya climatic conditions.

Keywords: adsorption, cooling, Egypt, environment, solar energy

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7860 Synthesis of Magnetic Plastic Waste-Reduced Graphene Oxide Composite and Its Application in Dye Adsorption from Aqueous Solution

Authors: Pamphile Ndagijimana, Xuejiao Liu, Zhiwei Li, Yin Wang

Abstract:

The valorization of plastic wastes, as a mitigation strategy, is attracting the researchers’ attention since these wastes have raised serious environmental concerns. Plastic wastes have been reported to adsorb the organic pollutants in the water environment and to be the main vector of those pollutants in the aquatic environment, especially dyes, as a serious water pollution concern. Recycling technologies of plastic wastes such as landfills, incineration, and energy recovery have been adopted to manage those wastes before getting exposed to the environment. However, they are far from being widely accepted due to their related environmental pollution, lack of space for the landfill as well as high cost. Therefore, modification is necessary for green plastic adsorbent in water applications. Current routes for plastic modification into adsorbents are based on the combustion method, but they have weaknesses of air pollution as well as high cost. Thus, the green strategy for plastic modification into adsorbents is highly required. Furthermore, recent researchers recommended that if plastic wastes are combined with other solid carbon materials, they could promote their application in water treatment. Herein, we present new insight into using plastic waste-based materials as future green adsorbents. Magnetic plastic-reduced graphene oxide (MPrGO) composite was synthesized by cross-linking method and applied in removing methylene blue (MB) from an aqueous solution. Furthermore, the following advantages have been achieved: (i) The density of plastic and reduced graphene oxide were enhanced, (ii) no second pollution of black color in solution, (iii) small amount of graphene oxide (1%) was linked on 10g of plastic waste, and the composite presented the high removal efficiency, (iv) easy recovery of adsorbent from water. The low concentration of MB (10-30mg/L) was all removed by 0.3g of MPrGO. Different characterization techniques such as XRD, SEM, FTIR, BET, XPS, and Raman spectroscopy were performed, and the results confirmed a conjugation between plastic waste and graphene oxide. This MPrGO composite presented a good prospect for the valorization of plastic waste, and it is a promising composite material in water treatment.

Keywords: plastic waste, graphene oxide, dye, adsorption

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7859 Model the Off-Shore Ocean-Sea Waves to Generate Electric Power by Design of a Converting Device

Authors: Muthana A. M. Jameel Al-Jaboori

Abstract:

In this paper, we will present a mathematical model to design a system able to generate electricity from ocean-sea waves. We will use the basic principles of the transfer of the energy potential of waves in a chamber to force the air inside a vertical or inclined cylindrical column, which is topped by a wind turbine to rotate the electric generator. The present mathematical model included a high number of variables such as the wave, height, width, length, velocity, and frequency, as well as others for the energy cylindrical column, like varying diameters and heights, and the wave chamber shape diameter and height. While for the wells wind turbine the variables included the number of blades, length, width, and clearance, as well as the rotor and tip radius. Additionally, the turbine rotor and blades must be made from the light and strong material for a smooth blade surface. The variables were too vast and high in number. Then the program was run successfully within the MATLAB and presented very good modeling results.

Keywords: water wave, models, Wells turbine, MATLAB program

Procedia PDF Downloads 337
7858 Manganese Imidazole Complexes: Electrocatalytic Hydrogen Production

Authors: Vishakha Kaim, Mookan Natarajan, Sandeep Kaur-Ghumaan

Abstract:

Hydrogen is one of the most abundant elements present on earth’s crust and considered to be the simplest element in existence. It is not found naturally as a gas on earth and thus has to be manufactured. Hydrogen can be produced from a variety of sources, i.e., water, fossil fuels, or biomass and it is a byproduct of many chemical processes. It is also considered as a secondary source of energy commonly referred to as an energy carrier. Though hydrogen is not widely used as a fuel, it still has the potential for greater use in the future as a clean and renewable source of energy. Electrocatalysis is one of the important source for the production of hydrogen which could contribute to this prominent challenge. Metals such as platinum and palladium are considered efficient for hydrogen production but with limited applications. As a result, a wide variety of metal complexes with earth abundant elements and varied ligand environments have been explored for the electrochemical production of hydrogen. In nature, [FeFe] hydrogenase enzyme present in DesulfoVibrio desulfuricans and Clostridium pasteurianum catalyses the reversible interconversion of protons and electrons into dihydrogen. Since the first structure for the enzyme was reported in 1990s, a range of iron complexes has been synthesized as structural and functional mimics of the enzyme active site. Mn is one of the most desirable element for sustainable catalytic transformations, immediately behind Fe and Ti. Only limited number manganese complexes have been reported in the last two decades as catalysts for proton reduction. Furthermore, redox reactions could be carried out in a facile manner, due to the capability of manganese complexes to be stable at different oxidation states. Herein are reported, four µ2-thiolate bridged manganese complexes [Mn₂(CO)₆(μ-S₂N₄C₁₄H₁₀)] 1, [Mn₂(CO)7(μ- S₂N₄C₁₄H₁₀)] 2, Mn₂(CO)₆(μ-S₄N₂C₁₄H₁₀)] 3 and [Mn₂(CO)(μ- S₄N₂C₁₄H₁₀)] 4 have been synthesized and characterized. The cyclic voltammograms of the complexes displayed irreversible reduction peaks in the range - 0.9 to -1.3 V (vs. Fc⁺/Fc in acetonitrile at 0.1 Vs⁻¹). The complexes were catalytically active towards proton reduction in the presence of trifluoroacetic acid as seen from electrochemical investigations.

Keywords: earth abundant, electrocatalytic, hydrogen, manganese

Procedia PDF Downloads 159
7857 Simplified Measurement of Occupational Energy Expenditure

Authors: J. Wicks

Abstract:

Aim: To develop a simple methodology to allow collected heart rate (HR) data from inexpensive wearable devices to be expressed in a suitable format (METs) to quantitate occupational (and recreational) activity. Introduction: Assessment of occupational activity is commonly done by utilizing questionnaires in combination with prescribed MET levels of a vast range of previously measured activities. However for any individual the intensity of performing a specific activity can vary significantly. Ideally objective measurement of individual activity is preferred. Though there are a wide range of HR recording devices there is a distinct lack methodology to allow processing of collected data to quantitate energy expenditure (EE). The HR index equation expresses METs in relation to relative HR i.e. the ratio of activity HR to resting HR. The use of this equation provides a simple utility for objective measurement of EE. Methods: During a typical occupational work period of approximately 8 hours HR data was recorded using a Polar RS 400 wrist monitor. Recorded data was downloaded to a Windows PC and non HR data was stripped from the ASCII file using ‘Notepad’. The HR data was exported to a spread sheet program and sorted by HR range into a histogram format. Three HRs were determined, namely a resting HR (the HR delimiting the lowest 30 minutes of recorded data), a mean HR and a peak HR (the HR delimiting the highest 30 minutes of recorded data). HR indices were calculated (mean index equals mean HR/rest HR and peak index equals peak HR/rest HR) with mean and peak indices being converted to METs using the HR index equation. Conclusion: Inexpensive HR recording devices can be utilized to make reasonable estimates of occupational (or recreational) EE suitable for large scale demographic screening by utilizing the HR index equation. The intrinsic value of the HR index equation is that it is independent of factors that influence absolute HR, namely fitness, smoking and beta-blockade.

Keywords: energy expenditure, heart rate histograms, heart rate index, occupational activity

Procedia PDF Downloads 284
7856 Numerical and Experimental Analysis of Temperature Distribution and Electric Field in a Natural Rubber Glove during Microwave Heating

Authors: U. Narumitbowonkul, P. Keangin, P. Rattanadecho

Abstract:

Both numerical and experimental investigation of the temperature distribution and electric field in a natural rubber glove (NRG) during microwave heating are studied. A three-dimensional model of NRG and microwave oven are considered in this work. The influences of position, heating time and rotation angle of NRG on temperature distribution and electric field are presented in details. The coupled equations of electromagnetic wave propagation and heat transfer are solved using the finite element method (FEM). The numerical model is validated with an experimental study at a frequency of 2.45 GHz. The results show that the numerical results closely match the experimental results. Furthermore, it is found that the temperature distribution and electric field increases with increasing heating time. The hot spot zone appears in NRG at the tip of middle finger while the maximum temperature occurs in case of rotation angle of NRG = 60 degree. This investigation provides the essential aspects for a fundamental understanding of heat transport of NRG using microwave energy in industry.

Keywords: electric field, finite element method, microwave energy, natural rubber glove

Procedia PDF Downloads 250
7855 Effect of Dietary Spirulina Powder on Growth Performance, Body Composition, Hematological, Biological and Immunological Parameters of Oscar Fish, Astronotus ocellatus

Authors: Negar Ghotbeddin

Abstract:

In this study, the changes in survival, growth, body composition, hematological, biochemical and immunological parameters of oscar fish (Astronotus ocellatus) have been investigated with dietary spirulina powder supplementation. Total of 300 fish with an initial weight of 8.37 ± 0.36 was distributed to three treatments and one control (0%). The fish were fed 8 weeks with diets containing different concentrations of S. powder: (control (0%), 2.5%, 5%, and 10%). Then sampling was done, and different parameters were measured by standard methods. Growth performance such as weight gain (%), specific growth rate (SGR) and feed conversion ratio (FCR) significantly improved in fish fed with S. powder (p < 0.5). Crude protein significantly increased in the S. powder supplemented groups (p < 0.5). However, crude lipid decreased with the increasing of dietary S. powder levels. Total protein increased in fish fed with 10% S. powder. Triglycerides and cholesterol decreased with the increasing of dietary S. powder levels. Immunological parameters including C3 and C4 increased significantly with the increasing of dietary S. powder levels, and lysozyme was improved in 10% S. powder. Results of this study indicated that S. powder had positive effects on Oscar fish and the best values were observed at 10 % S. powder.

Keywords: spirulina powder, growth performance, body composition, hematology, immunity, Astronotus ocellatus

Procedia PDF Downloads 153
7854 A Simulation Study of Direct Injection Compressed Natural Gas Spark Ignition Engine Performance Utilizing Turbulent Jet Ignition with Controlled Air Charge

Authors: Siyamak Ziyaei, Siti Khalijah Mazlan, Petros Lappas

Abstract:

Compressed Natural Gas (CNG) mainly consists of Methane CH₄ and has a low carbon to hydrogen ratio relative to other hydrocarbons. As a result, it has the potential to reduce CO₂ emissions by more than 20% relative to conventional fuels like diesel or gasoline Although Natural Gas (NG) has environmental advantages compared to other hydrocarbon fuels whether they are gaseous or liquid, its main component, CH₄, burns at a slower rate than conventional fuels A higher pressure and a leaner cylinder environment will overemphasize slow burn characteristic of CH₄. Lean combustion and high compression ratios are well-known methods for increasing the efficiency of internal combustion engines. In order to achieve successful CNG lean combustion in Spark Ignition (SI) engines, a strong ignition system is essential to avoid engine misfires, especially in ultra-lean conditions. Turbulent Jet Ignition (TJI) is an ignition system that employs a pre-combustion chamber to ignite the lean fuel mixture in the main combustion chamber using a fraction of the total fuel per cycle. TJI enables ultra-lean combustion by providing distributed ignition sites through orifices. The fast burn rate provided by TJI enables the ordinary SI engine to be comparable to other combustion systems such as Homogeneous Charge Compression Ignition (HCCI) or Controlled Auto-Ignition (CAI) in terms of thermal efficiency, through the increased levels of dilution without the need of sophisticated control systems. Due to the physical geometry of TJIs, which contain small orifices that connect the prechamber to the main chamber, scavenging is one of the main factors that reduce TJI performance. Specifically, providing the right mixture of fuel and air has been identified as a key challenge. The reason for this is the insufficient amount of air that is pushed into the pre-chamber during each compression stroke. There is also the problem that combustion residual gases such as CO₂, CO and NOx from the previous combustion cycle dilute the pre- chamber fuel-air mixture preventing rapid combustion in the pre-chamber. An air-controlled active TJI is presented in this paper in order to address these issues. By applying air to the pre-chamber at a sufficient pressure, residual gases are exhausted, and the air-fuel ratio is controlled within the pre-chamber, thereby improving the quality of combustion. This paper investigates the 3D-simulated combustion characteristics of a Direct Injected (DI-CNG) fuelled SI en- gine with a pre-chamber equipped with an air channel by using AVL FIRE software. Experiments and simulations were performed at the Worldwide Mapping Point (WWMP) at 1500 Revolutions Per Minute (RPM), 3.3 bar Indicated Mean Effective Pressure (IMEP), using only conventional spark plugs as the baseline. After validating simulation data, baseline engine conditions were set for all simulation scenarios at λ=1. Following that, the pre-chambers with and without an auxiliary fuel supply were simulated. In the simulated (DI-CNG) SI engine, active TJI was observed to perform better than passive TJI and spark plug. In conclusion, the active pre-chamber with an air channel demon-strated an improved thermal efficiency (ηth) over other counterparts and conventional spark ignition systems.

Keywords: turbulent jet ignition, active air control turbulent jet ignition, pre-chamber ignition system, active and passive pre-chamber, thermal efficiency, methane combustion, internal combustion engine combustion emissions

Procedia PDF Downloads 74
7853 Evaluation of Railway Network and Service Performance Based on Transportation Sustainability in DKI Jakarta

Authors: Nur Bella Octoria Bella, Ayomi Dita Rarasati

Abstract:

DKI Jakarta is Indonesia's capital city with the 10th highest congestion rate in the world based on the 2019 traffic index. Other than that based on World Air Quality Report in 2019 showed DKI Jakarta's air pollutant concentrate 49.4 µg and the 5th highest air pollutant in the world. In the urban city nowadays, the mobility rate is high enough and the efficiency for sustainability assessment in transport infrastructure development is needed. This efficiency is the important key for sustainable infrastructure development. DKI Jakarta is nowadays in the process of constructing the railway infrastructure to support the transportation system. The problems appearing are the railway infrastructure networks and the service in DKI Jakarta already planned based on sustainability factors or not. Therefore, the aim of this research is to make the evaluation of railways infrastructure networks performance and services in DKI Jakarta regards on the railway sustainability key factors. Further, this evaluation will be used to make the railway sustainability assessment framework and to offer some of the alternative solutions to improve railway transportation sustainability in DKI Jakarta. Firstly a very detailed literature review of papers that have focused on railway sustainability factors and their improvements of railway sustainability, published in the scientific journal in the period 2011 until 2021. Regarding the sustainability factors from the literature review, further, it is used to assess the current condition of railway infrastructure in DKI Jakarta. The evaluation will be using a Likert rate questionnaire and directed to the transportation railway expert and the passenger. Furthermore, the mapping and evaluation rate based on the sustainability factors will be compared to the effect factors using the Analytical Hierarchical Process (AHP). This research offers the network's performance and service rate impact on the sustainability aspect and the passenger willingness for using the rail public transportation in DKI Jakarta.

Keywords: transportation sustainability, railway transportation, sustainability, DKI Jakarta

Procedia PDF Downloads 148
7852 Exploring the Role of Building Information Modeling for Delivering Successful Construction Projects

Authors: Muhammad Abu Bakar Tariq

Abstract:

Construction industry plays a crucial role in the progress of societies and economies. Furthermore, construction projects have social as well as economic implications, thus, their success/failure have wider impacts. However, the industry is lagging behind in terms of efficiency and productivity. Building Information Modeling (BIM) is recognized as a revolutionary development in Architecture, Engineering and Construction (AEC) industry. There are numerous interest groups around the world providing definitions of BIM, proponents describing its advantages and opponents identifying challenges/barriers regarding adoption of BIM. This research is aimed at to determine what actually BIM is, along with its potential role in delivering successful construction projects. The methodology is critical analysis of secondary data sources i.e. information present in public domain, which include peer reviewed journal articles, industry and government reports, conference papers, books, case studies etc. It is discovered that clash detection and visualization are two major advantages of BIM. Clash detection option identifies clashes among structural, architectural and MEP designs before construction actually commences, which subsequently saves time as well as cost and ensures quality during execution phase of a project. Visualization is a powerful tool that facilitates in rapid decision-making in addition to communication and coordination among stakeholders throughout project’s life cycle. By eliminating inconsistencies that consume time besides cost during actual construction, improving collaboration among stakeholders throughout project’s life cycle, BIM can play a positive role to achieve efficiency and productivity that consequently deliver successful construction projects.

Keywords: building information modeling, clash detection, construction project success, visualization

Procedia PDF Downloads 247
7851 Experimental Study of Impregnated Diamond Bit Wear During Sharpening

Authors: Rui Huang, Thomas Richard, Masood Mostofi

Abstract:

The lifetime of impregnated diamond bits and their drilling efficiency are in part governed by the bit wear conditions, not only the extent of the diamonds’ wear but also their exposure or protrusion out of the matrix bonding. As much as individual diamonds wear, the bonding matrix does also wear through two-body abrasion (direct matrix-rock contact) and three-body erosion (cuttings trapped in the space between rock and matrix). Although there is some work dedicated to the study of diamond bit wear, there is still a lack of understanding on how matrix erosion and diamond exposure relate to the bit drilling response and drilling efficiency, as well as no literature on the process that governs bit sharpening a procedure commonly implemented by drillers when the extent of diamond polishing yield extremely low rate of penetration. The aim of this research is (i) to derive a correlation between the wear state of the bit and the drilling performance but also (ii) to gain a better understanding of the process associated with tool sharpening. The research effort combines specific drilling experiments and precise mapping of the tool-cutting face (impregnated diamond bits and segments). Bit wear is produced by drilling through a rock sample at a fixed rate of penetration for a given period of time. Before and after each wear test, the bit drilling response and thus efficiency is mapped out using a tailored design experimental protocol. After each drilling test, the bit or segment cutting face is scanned with an optical microscope. The test results show that, under the fixed rate of penetration, diamond exposure increases with drilling distance but at a decreasing rate, up to a threshold exposure that corresponds to the optimum drilling condition for this feed rate. The data further shows that the threshold exposure scale with the rate of penetration up to a point where exposure reaches a maximum beyond which no more matrix can be eroded under normal drilling conditions. The second phase of this research focuses on the wear process referred as bit sharpening. Drillers rely on different approaches (increase feed rate or decrease flow rate) with the aim of tearing worn diamonds away from the bit matrix, wearing out some of the matrix, and thus exposing fresh sharp diamonds and recovering a higher rate of penetration. Although a common procedure, there is no rigorous methodology to sharpen the bit and avoid excessive wear or bit damage. This paper aims to gain some insight into the mechanisms that accompany bit sharpening by carefully tracking diamond fracturing, matrix wear, and erosion and how they relate to drilling parameters recorded while sharpening the tool. The results show that there exist optimal conditions (operating parameters and duration of the procedure) for sharpening that minimize overall bit wear and that the extent of bit sharpening can be monitored in real-time.

Keywords: bit sharpening, diamond exposure, drilling response, impregnated diamond bit, matrix erosion, wear rate

Procedia PDF Downloads 84
7850 Development of Water-Based Thermal Insulation Paints Using Silica Aerogel

Authors: Lu Yanru, Handojo Djati Utomo, Yin Xi Jiang, Li Xiaodong

Abstract:

Insulation plays a key role in the sustainable building due to the contribution of energy consumption reduction. Without sufficient insulation, a great amount of the energy used to heat or cool a building will be lost to the outdoors. In this study, we developed a highly efficient thermal insulation paint with the incorporation of silica aerogel. Silica aerogel, with a low thermal conductivity of 0.01 W/mK, has been successfully prepared from the solid waste from the incineration plants. It has been added into water-based paints to increase its thermal insulation properties. To investigate the thermal insulation performance of silica aerogel additive, the paint samples were mixed with silica aerogel at different sizes and with various portions. The thermal conductivity, water resistance, thermal stability and adhesion strength of the samples were tested and evaluated. The thermal diffusivity measurements proved that adding silica aerogel additive could improve the thermal insulation properties of the paint significantly. Up to 5 ˚C reductions were observed after applying paints with silica aerogel additive compare to the one without it. The results showed that the developed thermal insulation paints have great potential for an application in green and sustainable building.

Keywords: silica aerogel, thermal insulation, water-based paints, water resistant

Procedia PDF Downloads 162
7849 Experimental Determination of Shear Strength Properties of Lightweight Expanded Clay Aggregates Using Direct Shear and Triaxial Tests

Authors: Mahsa Shafaei Bajestani, Mahmoud Yazdani, Aliakbar Golshani

Abstract:

Artificial lightweight aggregates have a wide range of applications in industry and engineering. Nowadays, the usage of this material in geotechnical activities, especially as backfill in retaining walls has been growing due to the specific characteristics which make it a competent alternative to the conventional geotechnical materials. In practice, a material with lower weight but higher shear strength parameters would be ideal as backfill behind retaining walls because of the important roles that these parameters play in decreasing the overall active lateral earth pressure. In this study, two types of Light Expanded Clay Aggregates (LECA) produced in the Leca factory are investigated. LECA is made in a rotary kiln by heating natural clay at different temperatures up to 1200 °C making quasi-spherical aggregates with different sizes ranged from 0 to 25 mm. The loose bulk density of these aggregates is between 300 and 700 kN/m3. The purpose of this research is to determine the stress-strain behavior, shear strength parameters, and the energy absorption of LECA materials. Direct shear tests were conducted at five normal stresses of 25, 50, 75, 100, and 200 kPa. In addition, conventional triaxial compression tests were operated at confining pressures of 50, 100, and 200 kPa to examine stress-strain behavior. The experimental results show a high internal angle of friction and even a considerable amount of nominal cohesion despite the granular structure of LECA. These desirable properties along with the intrinsic low density of these aggregates make LECA as a very proper material in geotechnical applications. Furthermore, the results demonstrate that lightweight aggregates may have high energy absorption that is excellent alternative material in seismic isolations.

Keywords: expanded clay, direct shear test, triaxial test, shear properties, energy absorption

Procedia PDF Downloads 146