Search results for: sulphate resisting cement
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1065

Search results for: sulphate resisting cement

375 Waste Management in a Hot Laboratory of Japan Atomic Energy Agency – 2: Condensation and Solidification Experiments on Liquid Waste

Authors: Sou Watanabe, Hiromichi Ogi, Atsuhiro Shibata, Kazunori Nomura

Abstract:

As a part of STRAD project conducted by JAEA, condensation of radioactive liquid waste containing various chemical compounds using reverse osmosis (RO) membrane filter was examined for efficient and safety treatment of the liquid wastes accumulated inside hot laboratories. NH4+ ion in the feed solution was successfully concentrated, and NH4+ ion involved in the effluents became lower than target value; 100 ppm. Solidification of simulated aqueous and organic liquid wastes was also tested. Those liquids were successfully solidified by adding cement or coagulants. Nevertheless, optimization in materials for confinement of chemicals is required for long time storage of the final solidified wastes.

Keywords: condensation, radioactive liquid waste, solidification, STRAD project

Procedia PDF Downloads 135
374 Employees’ Work Performance Quality Development for Organizational Competency

Authors: Pornpong Porpraphant

Abstract:

This paper aimed to demonstrate how work performance quality development activity carried out for employees in an organization could lead to the organizational success and competency as a whole. The case studies selected for this research were the Thai huge corporate including Siam Cement Group or SCG, PTT Public Company Limited, and Electricity Generating Authority of Thailand or EGAT. The in- depth interview was applied with the three main groups that included the facilitator group, the managerial group, and the operational officer group. The Plan- Do- Check- Act approach was also utilized as to build up a conceptual model in corporate management that fostered employees’ knowledge acquisition, resulting in an improved work performance.

Keywords: high performance organization, quality, work performance quality development

Procedia PDF Downloads 277
373 Numerical Simulation of Footing on Reinforced Loose Sand

Authors: M. L. Burnwal, P. Raychowdhury

Abstract:

Earthquake leads to adverse effects on buildings resting on soft soils. Mitigating the response of shallow foundations on soft soil with different methods reduces settlement and provides foundation stability. Few methods such as the rocking foundation (used in Performance-based design), deep foundation, prefabricated drain, grouting, and Vibro-compaction are used to control the pore pressure and enhance the strength of the loose soils. One of the problems with these methods is that the settlement is uncontrollable, leading to differential settlement of the footings, further leading to the collapse of buildings. The present study investigates the utility of geosynthetics as a potential improvement of the subsoil to reduce the earthquake-induced settlement of structures. A steel moment-resisting frame building resting on loose liquefiable dry soil, subjected to Uttarkashi 1991 and Chamba 1995 earthquakes, is used for the soil-structure interaction (SSI) analysis. The continuum model can simultaneously simulate structure, soil, interfaces, and geogrids in the OpenSees framework. Soil is modeled with PressureDependentMultiYield (PDMY) material models with Quad element that provides stress-strain at gauss points and is calibrated to predict the behavior of Ganga sand. The model analyzed with a tied degree of freedom contact reveals that the system responses align with the shake table experimental results. An attempt is made to study the responses of footing structure and geosynthetics with unreinforced and reinforced bases with varying parameters. The result shows that geogrid reinforces shallow foundation effectively reduces the settlement by 60%.

Keywords: settlement, shallow foundation, SSI, continuum FEM

Procedia PDF Downloads 173
372 Cement Mortar Lining as a Potential Source of Water Contamination

Authors: M. Zielina, W. Dabrowski, E. Radziszewska-Zielina

Abstract:

Several different cements have been tested to evaluate their potential to leach calcium, chromium and aluminum ions in soft water environment. The research allows comparing some different cements in order to the potential risk of water contamination. This can be done only in the same environment. To reach the results in reasonable short time intervals and to make heavy metals measurements with high accuracy, demineralized water was used. In this case the conditions of experiments are far away from the water supply practice, but short time experiments and measurably high concentrations of elements in the water solution are an important advantage. Moreover leaching mechanisms can be recognized, our experiments reported here refer to this kind of cements evaluation.

Keywords: concrete corrosion, hydrogen sulfide, odors, reinforced concrete sewers, sewerage

Procedia PDF Downloads 187
371 Seismic Vulnerability of Structures Designed in Accordance with the Allowable Stress Design and Load Resistant Factor Design Methods

Authors: Mohammadreza Vafaei, Amirali Moradi, Sophia C. Alih

Abstract:

The method selected for the design of structures not only can affect their seismic vulnerability but also can affect their construction cost. For the design of steel structures, two distinct methods have been introduced by existing codes, namely allowable stress design (ASD) and load resistant factor design (LRFD). This study investigates the effect of using the aforementioned design methods on the seismic vulnerability and construction cost of steel structures. Specifically, a 20-story building equipped with special moment resisting frame and an eccentrically braced system was selected for this study. The building was designed for three different intensities of peak ground acceleration including 0.2 g, 0.25 g, and 0.3 g using the ASD and LRFD methods. The required sizes of beams, columns, and braces were obtained using response spectrum analysis. Then, the designed frames were subjected to nine natural earthquake records which were scaled to the designed response spectrum. For each frame, the base shear, story shears, and inter-story drifts were calculated and then were compared. Results indicated that the LRFD method led to a more economical design for the frames. In addition, the LRFD method resulted in lower base shears and larger inter-story drifts when compared with the ASD method. It was concluded that the application of the LRFD method not only reduced the weights of structural elements but also provided a higher safety margin against seismic actions when compared with the ASD method.

Keywords: allowable stress design, load resistant factor design, nonlinear time history analysis, seismic vulnerability, steel structures

Procedia PDF Downloads 249
370 Seismic Assessment of Passive Control Steel Structure with Modified Parameter of Oil Damper

Authors: Ahmad Naqi

Abstract:

Today, the passively controlled buildings are extensively becoming popular due to its excellent lateral load resistance circumstance. Typically, these buildings are enhanced with a damping device that has high market demand. Some manufacturer falsified the damping device parameter during the production to achieve the market demand. Therefore, this paper evaluates the seismic performance of buildings equipped with damping devices, which their parameter modified to simulate the falsified devices, intentionally. For this purpose, three benchmark buildings of 4-, 10-, and 20-story were selected from JSSI (Japan Society of Seismic Isolation) manual. The buildings are special moment resisting steel frame with oil damper in the longitudinal direction only. For each benchmark buildings, two types of structural elements are designed to resist the lateral load with and without damping devices (hereafter, known as Trimmed & Conventional Building). The target building was modeled using STERA-3D, a finite element based software coded for study purpose. Practicing the software one can develop either three-dimensional Model (3DM) or Lumped Mass model (LMM). Firstly, the seismic performance of 3DM and LMM models was evaluated and found excellent coincide for the target buildings. The simplified model of LMM used in this study to produce 66 cases for both of the buildings. Then, the device parameters were modified by ± 40% and ±20% to predict many possible conditions of falsification. It is verified that the building which is design to sustain the lateral load with support of damping device (Trimmed Building) are much more under threat as a result of device falsification than those building strengthen by damping device (Conventional Building).

Keywords: passive control system, oil damper, seismic assessment, lumped mass model

Procedia PDF Downloads 97
369 Effect of Mineral Additives on Improving the Geotechnical Properties of Soils in Chief

Authors: Rabah Younes

Abstract:

The reduction of available land resources and the increased cout associated with the use of high quality materials have led to the need for local soils to be used in geotechnical construction, however; poor engineering properties of these soils pose difficulties for constructions project and need to be stabilized to improve their properties in other works unsuitable soils with low bearing capacity , high plasticity coupled with high instability are frequently encountered hence, there is a need to improve the physical and mechanical characteristics of these soils to make theme more suitable for construction this can be done by using different mechanical and chemical methods clayey soil stabilization has been practiced for sometime but mixing additives, such us cement, lime and fly ash to the soil to increase its strength.

Keywords: clay, soil stabilization, naturaln pozzolana, atterberg limits, compaction, compressive strength shear strength, curing

Procedia PDF Downloads 286
368 Influence of Silica Fume on Ultrahigh Performance Concrete

Authors: Vitoldas Vaitkevičius, Evaldas Šerelis

Abstract:

Silica fume, also known as microsilica (MS) or condensed silica fume is a by-product of the production of silicon metal or ferrosilicon alloys. Silica fume is one of the most effective pozzolanic additives which could be used for ultrahigh performance and other types of concrete. Despite the fact, however is not entirely clear, which amount of silica fume is most optimal for UHPC. Main objective of this experiment was to find optimal amount of silica fume for UHPC with and without thermal treatment, when different amount of quartz powder is substituted by silica fume. In this work were investigated four different composition of UHPC with different amount of silica fume. Silica fume were added 0, 10, 15 and 20% of cement (by weight) to UHPC mixture. Optimal amount of silica fume was determined by slump, viscosity, qualitative and quantitative XRD analysis and compression strength tests methods.

Keywords: compressive strength, silica fume, ultrahigh performance concrete, XRD

Procedia PDF Downloads 277
367 Modeling and Simulation of Honeycomb Steel Sandwich Panels under Blast Loading

Authors: Sayed M. Soleimani, Nader H. Ghareeb, Nourhan H. Shaker, Muhammad B. Siddiqui

Abstract:

Honeycomb sandwich panels have been widely used as protective structural elements against blast loading. The main advantages of these panels include their light weight due to the presence of voids, as well as their energy absorption capability. Terrorist activities have imposed new challenges to structural engineers to design protective measures for vital structures. Since blast loading is not usually considered in the load combinations during the design process of a structure, researchers around the world have been motivated to study the behavior of potential elements capable of resisting sudden loads imposed by the detonation of explosive materials. One of the best candidates for this objective is the honeycomb sandwich panel. Studying the effects of explosive materials on the panels requires costly and time-consuming experiments. Moreover, these type of experiments need permission from defense organizations which can become a hurdle. As a result, modeling and simulation using an appropriate tool can be considered as a good alternative. In this research work, the finite element package ABAQUS® is used to study the behavior of hexagonal and squared honeycomb steel sandwich panels under the explosive effects of different amounts of trinitrotoluene (TNT). The results of finite element modeling of a specific honeycomb configuration are initially validated by comparing them with the experimental results from literature. Afterwards, several configurations including different geometrical properties of the honeycomb wall are investigated and the results are compared with the original model. Finally, the effectiveness of the core shape and wall thickness are discussed, and conclusions are made.

Keywords: Abaqus, blast loading, finite element modeling, steel honeycomb sandwich panel

Procedia PDF Downloads 330
366 Passive Solar Distiller with Low Cost of Implementation, Operation and Maintenance

Authors: Valentina Alessandra Carvalho do Vale, Elmo Thiago Lins Cöuras Ford, Rudson de Sousa Lima

Abstract:

Around the planet Earth, access to clean water is a problem whose importance has increased due to population growth and its misuse. Thus, projects that seek to transform water sources improper (salty and brackish) in drinking water sources are current issues. However, this transformation generally requires a high cost of implementation, operation and maintenance. In this context, the aim of this work is the development of a passive solar distiller for brackish water, made from recycled and durable materials such as aluminum, cement, glass and PVC basins. The results reveal factors that influence the performance and viability of the expansion project.

Keywords: solar distiller, passive distiller, distiller with pyramidal roof, ecologically correct

Procedia PDF Downloads 385
365 Recycling Carbon Fibers/Epoxy Composites Wastes in Building Materials Based on Geopolymer Binders

Authors: A. Saccani, I. Lancellotti, E. Bursi

Abstract:

Scraps deriving from the production of epoxy-carbon fibers composites have been recycled as a reinforcement to produce building materials. Short chopped fibers (5-7 mm length) have been added at low volume content (max 10%) to produce mortars. The microstructure, mechanical properties (mainly flexural strength) and dimensional stability of the derived materials have been investigated. Two different types of matrix have been used: one based on conventional Portland Cement and the other containing geopolymers formed starting from activated metakaolin and fly ashes. In the second case the materials is almost completely made of recycled ingredients. This is an attempt to produce reliable materials solving waste disposal problems. The first collected results show promising results.

Keywords: building materials, carbon fibres, fly ashes, geopolymers

Procedia PDF Downloads 140
364 Experimental Study on Granulated Steel Slag as an Alternative to River Sand

Authors: K. Raghu, M. N. Vathhsala, Naveen Aradya, Sharth

Abstract:

River sand is the most preferred fine aggregate for mortar and concrete. River sand is a product of natural weathering of rocks over a period of millions of years and is mined from river beds. Sand mining has disastrous environmental consequences. The excessive mining of river bed is creating an ecological imbalance. This has lead to have restrictions imposed by ministry of environment on sand mining. Driven by the acute need for sand, stone dust or manufactured sand prepared from the crushing and screening of coarse aggregate is being used as sand in the recent past. However manufactured sand is also a natural material and has quarrying and quality issues. To reduce the burden on the environment, alternative materials to be used as fine aggregates are being extensively investigated all over the world. Looking to the quantum of requirements, quality and properties there has been a global consensus on a material – Granulated slags. Granulated slag has been proven as a suitable material for replacing natural sand / crushed fine aggregates. In developed countries, the use of granulated slag as fine aggregate to replace natural sand is well established and is in regular practice. In the present paper Granulated slag has been experimented for usage in mortar. Slags are the main by-products generated during iron and steel production in the steel industry. Over the past decades, the steel production has increased and, consequently, the higher volumes of by-products and residues generated which have driven to the reuse of these materials in an increasingly efficient way. In recent years new technologies have been developed to improve the recovery rates of slags. Increase of slags recovery and use in different fields of applications like cement making, construction and fertilizers help in preserving natural resources. In addition to the environment protection, these practices produced economic benefits, by providing sustainable solutions that can allow the steel industry to achieve its ambitious targets of “zero waste” in coming years. Slags are generated at two different stages of steel production, iron making and steel making known as BF(Blast Furnace) slag and steel slag respectively. The slagging agent or fluxes, such as lime stone, dolomite and quartzite added into BF or steel making furnaces in order to remove impurities from ore, scrap and other ferrous charges during smelting. The slag formation is the result of a complex series of physical and chemical reactions between the non-metallic charge(lime stone, dolomite, fluxes), the energy sources(coal, coke, oxygen, etc.) and refractory materials. Because of the high temperatures (about 15000 C) during their generation, slags do not contain any organic substances. Due to the fact that slags are lighter than the liquid metal, they float and get easily removed. The slags protect the metal bath from atmosphere and maintain temperature through a kind of liquid formation. These slags are in liquid state and solidified in air after dumping in the pit or granulated by impinging water systems. Generally, BF slags are granulated and used in cement making due to its high cementious properties, and steel slags are mostly dumped due to unfavourable physio-chemical conditions. The increasing dump of steel slag not only occupies a plenty of land but also wastes resources and can potentially have an impact on the environment due to water pollution. Since BF slag contains little Fe and can be used directly. BF slag has found a wide application, such as cement production, road construction, Civil Engineering work, fertilizer production, landfill daily cover, soil reclamation, prior to its application outside the iron and steel making process.

Keywords: steel slag, river sand, granulated slag, environmental

Procedia PDF Downloads 227
363 Correlation of SPT N-Value and Equipment Drilling Parameters in Deep Soil Mixing

Authors: John Eric C. Bargas, Ma. Cecilia M. Marcos

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One of the most common ground improvement techniques is Deep Soil Mixing (DSM). As the technique progresses, there is still lack in the development when it comes to depth control. This was the issue experienced during the installation of DSM in one of the National projects in the Philippines. This study assesses the feasibility of using equipment drilling parameters such as hydraulic pressure, drilling speed and rotational speed in determining the Standard Penetration Test N-value of a specific soil. Hydraulic pressure and drilling speed with a constant rotational speed of 30 rpm have a positive correlation with SPT N-value for cohesive soil and sand. A linear trend was observed for cohesive soil. The correlation of SPT N-value and hydraulic pressure yielded a R²=0.5377 while the correlation of SPT N-value and drilling speed has a R²=0.6355. While the best fitted model for sand is polynomial trend. The correlation of SPT N-value and hydraulic pressure yielded a R²=0.7088 while the correlation of SPT N-value and drilling speed has a R²=0.4354. The low correlation may be attributed to the behavior of sand when the auger penetrates. Sand tends to follow the rotation of the auger rather than resisting which was observed for very loose to medium dense sand. Specific Energy and the product of hydraulic pressure and drilling speed yielded same R² with a positive correlation. Linear trend was observed for cohesive soil while polynomial trend for sand. Cohesive soil yielded a R²=0.7320 which has a strong relationship. Sand also yielded a strong relationship having a coefficient of determination, R²=0.7203. It is feasible to use hydraulic pressure and drilling speed to estimate the SPT N-value of the soil. Also, the product of hydraulic pressure and drilling speed can be a substitute to specific energy when estimating the SPT N-value of a soil. However, additional considerations are necessary to account for other influencing factors like ground water and physical and mechanical properties of soil.

Keywords: ground improvement, equipment drilling parameters, standard penetration test, deep soil mixing

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362 Energy Management System

Authors: S. Periyadharshini, K. Ramkumar, S. Jayalalitha, M. GuruPrasath, R. Manikandan

Abstract:

This paper presents a formulation and solution for industrial load management and product grade problem. The formulation is created using linear programming technique thereby optimizing the electricity cost by scheduling the loads satisfying the process, storage, time zone and production constraints which will create an impact of reducing maximum demand and thereby reducing the electricity cost. Product grade problem is formulated using integer linear programming technique of optimization using lingo software and the results show that overall increase in profit margin. In this paper, time of use tariff is utilized and this technique will provide significant reductions in peak electricity consumption.

Keywords: cement industries, integer programming, optimal formulation, objective function, constraints

Procedia PDF Downloads 562
361 Analysis of the Effect of Increased Self-Awareness on the Amount of Food Thrown Away

Authors: Agnieszka Dubiel, Artur Grabowski, Tomasz Przerywacz, Mateusz Roganowicz, Patrycja Zioty

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Food waste is one of the most significant challenges humanity is facing nowadays. Every year, reports from global organizations show the scale of the phenomenon, although society's awareness is still insufficient. One-third of the food produced in the world is wasted at various points in the food supply chain. Wastes are present from the delivery through the food preparation and distribution to the end of the sale and consumption. The first step in understanding and resisting the phenomenon is a thorough analysis of the everyday behaviors of humanity. This concept is understood as finding the correlation between the type of food and the reason for throwing it out and wasting it. Those actions were identified as a critical step in the start of work to develop technology to prevent food waste. In this paper, the problem mentioned above was analyzed by focusing on the inhabitants of Central Europe, especially Poland, aged 20-30. This paper provides an insight into collecting data through dedicated software and an organized database. The proposed database contains information on the amount, type, and reasons for wasting food in households. A literature review supported the work to answer research questions, compare the situation in Poland with the problem analyzed in other countries, and find research gaps. The proposed article examines the cause of food waste and its quantity in detail. This review complements previous reviews by emphasizing social and economic innovation in Poland's food waste management. The paper recommends a course of action for future research on food waste management and prevention related to the handling and disposal of food, emphasizing households, i.e., the last link in the supply chain.

Keywords: food waste, food waste reduction, consumer food waste, human-food interaction

Procedia PDF Downloads 95
360 Freeze-Thaw Resistance of Concretes with BFSA

Authors: Alena Sicakova

Abstract:

Air-cooled Blast furnace slag aggregate (BFSA) is usually referred to as a material providing for unique properties of concrete. On the other hand, negative influences are also presented in many aspects. The freeze-thaw resistance of concrete is dependent on many factors, including regional specifics and when a concrete mix is specified it is still difficult to tell its exact freeze-thaw resistance due to the different components affecting it. An important consideration in working with BFSA is the granularity and whether slag is sorted or not. The experimental part of the article represents a comparative testing of concrete using both the sorted and unsorted BFSA through the freeze-thaw resistance as an indicator of durability. Unsorted BFSA is able to be successfully used for concretes as they are specified for exposure class XF4 with providing that the type of cement is precisely selected.

Keywords: blast furnace slag aggregate, concrete, freeze-thaw resistance

Procedia PDF Downloads 378
359 Characterization of an Ecological Mortar Lightweight With Polystyrene

Authors: Aidoud Assia, Bencheikh Messaouda, Boukour Salima

Abstract:

Polystyrene is often seen in the ocean and on Algerian beaches, mainly as food containers. It's one of the top 10 most common items found there. This happens because it's light and easily carried away from its original source, like packaging or transport, into the environment. Unfortunately, it's not recycled much because it's not very profitable to do so. Hence, turning this waste into a resource can turn challenges into opportunities for a territory's economic and environmental development, which is the focus of this study. the goal is to analyze the physical and mechanical properties of a new type of mortar made from dune sand mixed with recycled polystyrene. it also aim to assess its potential for use in various construction applications. The mixtures were prepared by replacing portions of dune sand with polystyrene waste at varying volumes (10%, 20%, and 30%), while keeping the amount of cement constant. The results indicate a noticeable impact on both the physical and mechanical properties because of incorporating polystyrene waste.

Keywords: polystyrène, eco-mortier, sable de dune, résistance

Procedia PDF Downloads 19
358 Corrosion of Concrete Reinforcing Steel Bars Tested and Compared Between Various Protection Methods

Authors: P. van Tonder, U. Bagdadi, B. M. D. Lario, Z. Masina, T. R. Motshwari

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This paper analyses how concrete reinforcing steel bars corrode and how it can be minimised through the use of various protection methods against corrosion, such as metal-based paint, alloying, cathodic protection and electroplating. Samples of carbon steel bars were protected, using these four methods. Tests performed on the samples included durability, electrical resistivity and bond strength. Durability results indicated relatively low corrosion rates for alloying, cathodic protection, electroplating and metal-based paint. The resistivity results indicate all samples experienced a downward trend, despite erratic fluctuations in the data, indicating an inverse relationship between electrical resistivity and corrosion rate. The results indicated lowered bond strengths when the reinforced concrete was cured in seawater compared to being cured in normal water. It also showed that higher design compressive strengths lead to higher bond strengths which can be used to compensate for the loss of bond strength due to corrosion in a real-world application. In terms of implications, all protection methods have the potential to be effective at resisting corrosion in real-world applications, especially the alloying, cathodic protection and electroplating methods. The metal-based paint underperformed by comparison, most likely due to the nature of paint in general which can fade and chip away, revealing the steel samples and exposing them to corrosion. For alloying, stainless steel is the suggested material of choice, where Y-bars are highly recommended as smooth bars have a much-lowered bond strength. Cathodic protection performed the best of all in protecting the sample from corrosion, however, its real-world application would require significant evaluation into the feasibility of such a method.

Keywords: protection methods, corrosion, concrete, reinforcing steel bars

Procedia PDF Downloads 155
357 Effect of the Accelerated Carbonation in Fibercement Composites Reinforced with Eucalyptus Pulp and Nanofibrillated Cellulose

Authors: Viviane da Costa Correia, Sergio Francisco Santos, Holmer Savastano Junior

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The main purpose of this work was verify the influence of the accelerated carbonation in the physical and mechanical properties of the hybrid composites, reinforced with micro and nanofibers and composites with microfibers. The composites were produced by the slurry vacuum dewatering method, followed by pressing. It was produced using two formulations: 8% of eucalyptus pulp + 1% of the nanofibrillated cellulose and 9% of eucalyptus pulp, both were subjected to accelerated carbonation. The results showed that the accelerated carbonation contributed to improve the physical and mechanical properties of the hybrid composites and of the composites reinforced with microfibers (eucalyptus pulp).

Keywords: carbonation, cement composites, nanofibrillated cellulose, eucalyptus pulp

Procedia PDF Downloads 314
356 Development of Palm Kernel Shell Lightweight Masonry Mortar

Authors: Kazeem K. Adewole

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There need to construct building walls with lightweight masonry bricks/blocks and mortar to reduce the weight and cost of cooling/heating of buildings in hot/cold climates is growing partly due to legislations on energy use and global warming. In this paper, the development of Palm Kernel Shell masonry mortar (PKSMM) prepared with Portland cement and crushed PKS fine aggregate (an agricultural waste) is demonstrated. We show that PKSMM can be used as a lightweight mortar for the construction of lightweight masonry walls with good thermal insulation efficiency than the natural river sand commonly used for masonry mortar production.

Keywords: building walls, fine aggregate, lightweight masonry mortar, palm kernel shell, wall thermal insulation efficacy

Procedia PDF Downloads 301
355 Deployment of Information and Communication Technology (ICT) to Reduce Occurrences of Terrorism in Nigeria

Authors: Okike Benjamin

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Terrorism is the use of violence and threat to intimidate or coerce a person, group, society or even government especially for political purposes. Terrorism may be a way of resisting government by some group who may feel marginalized. It could also be a way of expressing displeasure over the activities of government. On 26th December, 2009, US placed Nigeria as a terrorist nation. Recently, the occurrences of terrorism in Nigeria have increased considerably. In Jos, Plateau state, Nigeria, there was a bomb blast which claimed many lives on the eve of 2010 Christmas. Similarly, there was another bomb blast in Mugadishi (Sani Abacha) Barracks Mammy market on the eve of 2011 New Year. For some time now, it is no longer news that bomb exploded in some Northern part of Nigeria. About 25 years ago, stopping terrorism in America by the Americans relied on old-fashioned tools such as strict physical security at vulnerable places, intelligence gathering by government agents, or individuals, vigilance on the part of all citizens, and a sense of community in which citizens do what could be done to protect each other. Just as technology has virtually been used to better the way many other things are done, so also this powerful new weapon called computer technology can be used to detect and prevent terrorism not only in Nigeria, but all over the world. This paper will x-ray the possible causes and effects of bomb blast, which is an act of terrorism and suggest ways in which Explosive Detection Devices (EDDs) and computer software technology could be deployed to reduce the occurrences of terrorism in Nigeria. This become necessary with the abduction of over 200 schoolgirls in Chibok, Borno State from their hostel by members of Boko Haram sect members on 14th April, 2014. Presently, Barrack Obama and other world leaders have sent some of their military personnel to help rescue those innocent schoolgirls whose offence is simply seeking to acquire western education which the sect strongly believe is forbidden.

Keywords: terrorism, bomb blast, computer technology, explosive detection devices, Nigeria

Procedia PDF Downloads 245
354 An Investigation on Ultrasonic Pulse Velocity of Hybrid Fiber Reinforced Concretes

Authors: Soner Guler, Demet Yavuz, Refik Burak Taymuş, Fuat Korkut

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Because of the easy applying and not costing too much, ultrasonic pulse velocity (UPV) is one of the most used non-destructive techniques to determine concrete characteristics along with impact-echo, Schmidt rebound hammer (SRH) and pulse-echo. This article investigates the relationship between UPV and compressive strength of hybrid fiber reinforced concretes. Water/cement ratio (w/c) was kept at 0.4 for all concrete mixes. Compressive strength of concrete was targeted at 35 MPa. UPV testing and compressive strength tests were carried out at the curing age of 28 days. The UPV of concrete containing steel fibers has been found to be higher than plain concrete for all the testing groups. It is decided that there is not a certain relationship between fiber addition and strength.

Keywords: ultrasonic pulse velocity, hybrid fiber, compressive strength, fiber

Procedia PDF Downloads 334
353 A Review: Recycled Materials Used in Construction

Authors: Oghenerukome Akponovo, Lynda I. Onyebuchukwu

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Construction waste, along with that of many other industries, contributes significantly to the world's annual solid waste totals. Most of these materials, such as ash from rice hulls, slags, cement kiln dust, tire ash, plastic waste (PW), and silica fumes, end up in landfills or waterways. Some of them might even end up polluting the air from high in the atmosphere. It's sustainable, cheap, and environmentally friendly to recycle these items into new building supplies. When constructing a "Green" structure, the materials employed have the potential to either exacerbate environmental imbalance or maintain a stable ecosystem. The purpose of this research is to take stock of what is already known about recycling's potential in the construction industry and to identify its deficiencies. Therefore, this study systematically reviews the wide range of recycled materials that go into building construction. Recognizing that the construction industry's use of recycled materials has an influence on the environment and that investigating these materials may have a substantial economic impact if they were discovered

Keywords: building, construction, recycled materials, waste management

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352 New Innovation and Sustainability in a Developing Country: The Case of Cameroon

Authors: Lema Catherine Forje

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Innovation activates the system of an economy to a new level. Innovation follows a process. The first step in innovation is the idea-generation process. There is widespread appreciation that people go to great lengths, incur expenses: energy and materials to generate innovative ideas. People get inspired, create, and connect. The inspiration also enables the building of a culture of innovation. Data collection was done through a face-to-face interview with the producer of the first Cameroon beer that came out in the early 1960s, a rice producing company, a cement producing company, and 100 women following a type of dressing commonly worn by Cameroonian women (wrappa). There were a total number of one hundred and three interviewees. The implication of this study is for everybody. It sheds light on the factors that are likely to sustain an innovation. Conclusion emphasises continuous research to keep giving the innovation a face lift.

Keywords: entrepreneurship, ideas, innovation, sustainability

Procedia PDF Downloads 274
351 Utilising Unground Oil Palm Ash in Producing Foamed Concrete and Its Implementation as an Interlocking Mortar-Less Block

Authors: Hanizam Awang, Mohammed Zuhear Al-Mulali

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In this study, the possibility of using unground oil palm ash (UOPA) for producing foamed concrete is investigated. The UOPA used in this study is produced by incinerating palm oil biomass at a temperature exceeding 1000ºC. A semi-structural density of 1300kg/m3 was used with filler to binder ratio of 1.5 and preliminary water to binder ratio of 0.45. Cement was replaced by UOPA at replacement levels of 0, 25, 35, 45, 55 and 65% by weight of binder. Properties such as density, compressive strength, drying shrinkage and water absorption were investigated to the age of 90 days. The mix with a 35% of UOPA content was chosen to be used as the base material of a newly designed interlocking, mortar-less block system.

Keywords: foamed concrete, oil palm ash, strength, interlocking block

Procedia PDF Downloads 244
350 Contamination of Groundwater by Nitrates, Nitrites, Ammonium and Phosphate in the Guelma-bouchegouf Irrigated Area (Northeastern Algeria)

Authors: Benhamza Moussa, Aissaoui Marwa, Touati Mounira, Chaoui Widad

Abstract:

The Guelma-Bouchegouf irrigated area is located in the northeast of Algeria, and it extends about 80 km. It was commissioned in 1996, with an irrigable area of 9250 ha, it spreads on both banks of the Seybouse Wadi and it is subdivided into five autonomous distribution sectors. In order to assess the state of groundwater quality, the results of the chemical analyzes were plotted on the Piper diagram, which shows that the chemical facies are sulfate-calcium chloride and sulfate-calcium with a slight tendency to migrate to chlorinated sulphate - sodium. The predominance of sulphates in the waters of the region is geologically explained by the existence in the Guelma Basin of evaporitic deposits, which are mainly represented by rock salt and gypsum. In addition to this natural origin, we can mention the anthropogenic origin, following the use of chemical fertilizers in the Guelma-Bouchegouf irrigated area. Na⁺ and Mg²⁺ show moderate to significant mineralization of water, closely correlated with very high conductivities. The values of the recorded conductivities vary from 1360 μs / cm (P3) to 4610 μs / cm (P10). These important values are due to dissolved salts on the one hand and the leaching of fertilizers by irrigation water on the other hand. NO₃⁻ and NH₄⁺ show little to significant pollution throughout the study area. Phosphate represents significant pollution, with excessive values far exceeding the allowable standard. With respect to ammonium, 87% of the sampling points present little pollution and 13 % significant pollution. Regarding phosphates, in the form of PO₄³⁻, groundwater in the study area represents significant pollution; all values far exceed the allowable standard.

Keywords: groundwater, organic parameters, standards, Pollution

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349 Dissolution Kinetics of Chevreul’s Salt in Ammonium Cloride Solutions

Authors: Mustafa Sertçelik, Turan Çalban, Hacali Necefoğlu, Sabri Çolak

Abstract:

In this study, Chevreul’s salt solubility and its dissolution kinetics in ammonium chloride solutions were investigated. Chevreul’s salt that we used in the studies was obtained by using the optimum conditions (ammonium sulphide concentration; 0,4 M, copper sulphate concentration; 0,25 M, temperature; 60°C, stirring speed; 600 rev/min, pH; 4 and reaction time; 15 mins) determined by T. Çalban et al. Chevreul’s salt solubility in ammonium chloride solutions and the kinetics of dissolution were investigated. The selected parameters that affect solubility were reaction temperature, concentration of ammonium chloride, stirring speed, and solid/liquid ratio. Correlation of experimental results had been achieved using linear regression implemented in the statistical package program statistica. The effect of parameters on Chevreul’s salt solubility was examined and integrated rate expression of dissolution rate was found using kinetic models in solid-liquid heterogeneous reactions. The results revealed that the dissolution rate of Chevreul’s salt was decreasing while temperature, concentration of ammonium chloride and stirring speed were increasing. On the other hand, dissolution rate was found to be decreasing with the increase of solid/liquid ratio. Based on result of the applications of the obtained experimental results to the kinetic models, we can deduce that Chevreul’s salt dissolution rate is controlled by diffusion through the ash (or product layer). Activation energy of the reaction of dissolution was found as 74.83 kJ/mol. The integrated rate expression along with the effects of parameters on Chevreul's salt solubility was found to be as follows: 1-3(1-X)2/3+2(1-X)= [2,96.1013.(CA)3,08 .(S/L)-038.(W)1,23 e-9001,2/T].t

Keywords: Chevreul's salt, copper, ammonium chloride, ammonium sulphide, dissolution kinetics

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348 Improvement of Deficient Soils in Nigeria Using Bagasse Ash - A Review

Authors: Musa Alhassan, Alhaji Mohammed Mustapha

Abstract:

Review of studies carried out on the use of bagasse ash in the improvement of deficient soils in Nigeria, with emphasis on lateritic and black cotton soils is presented. Although, the bagasse ash is mostly used as additive to the conventional soil stabilizer (cement and lime), the studies generally showed improvement of geotechnical properties of the soils either modified or stabilized with the ash. This showed the potentials of using this agricultural waste (bagasse ash) in the improvement of geotechnical properties of deficient soils. Thus suggesting that using this material at large scale level, in geotechnical engineering practice could help in the provision of stable and durable structures, reduce cost of soil improvement and also reduces environmental nuisance caused by the unused waste in Nigeria

Keywords: bagasse ash, black cotton soil, deficient soil, laterite, soil improvement

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347 An Advanced Method of Plant Preservation and Colour Retention of Herbarium Specimens

Authors: Abduraheem K., Suboohi Nasrin

Abstract:

Herbaria are specimens of preserved plants, which are very delicate and cellulosic in nature. While these collections are very useful for the enrichment of knowledge and are considered as natural heritage of our entire world, it is very important to preserve and conserve them. The significance is not only to prevent the herbaria from the deterioration of biological agencies but also to preserve its colours and retain natural colour. Colour is not only characteristic of a plant, but it can also help to identify closely related species or to distinguish a plant from a collection of herbaria. Keeping this in mind, a selective solution has been prepared for the conservation and preservation of herbarium in the present study. In this, the quantity of all the selected chemicals, i.e., formaldehyde and copper sulphate was kept constant, and the solution was prepared by dissolving it in distilled water by increasing the amount of picric acid (1, 2, 3, 4, and 5 ml). Fresh specimens of roses and bougainvillea were washed with distilled water and kept in the above solution for 10 to 15 minutes at room temperature. After 10 minutes, the specimen was removed from the solution, dried with the help of paper, and then pressed under the plant press. Blotting sheets were used to absorb the moisture content and were changed every 2 to 3 days to protect against fungal growth. The results revealed that all solutions had insecticidal properties and protected the herbarium specimen against pests. While in the case of colour retention, solution-1 and 2 were not satisfactory colour preservation, and solutions-3 and 5 maintained the colour of rose and bougainvillea leaves for 15 to 20 days and for a month, respectively. After that, the colour begins to fade, and the process is faster in rose leaves than in bougainvillea. And it was also observed that the colour of young leaves started to fade before that of older leaves. When the leaves of rose and bougainvillea are treated with Solution-4, then the colour of rose leaves is maintained for six months.

Keywords: solutions, colour retention, preservation and conservation, leaves of roses and bougainvillea

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346 The Battle between French and English in the Algerian University: Ideological and Pedagogical Stakes

Authors: Taoufik Djennane

Abstract:

Algeria is characterized by a fragmented language education policy. While pre-university education is entirely conducted in Arabic, higher education remains linguistically divided, with some fields offered in Arabic and others exclusively based on French. Within this linguistic policy, English remains far behind French. However, there has been a significant shift in the state’s linguistic orientation since the social riot of March 2019, known as El-Hirak, which ousted away the ex-president. Since then, social calls were voiced to get rid of French, and English started to receive an unprecedented political push. The historical decision only came at the beginning of the academic year 2023-2024 when the ministry of higher education imposed English as medium of instruction (hereafter EMI), especially in scientific and technological fields. As such, this paper considered this abrupt switch in the medium of instruction and its effects on the community of teachers. Building on a socio-psychological approach, teachers’ attitudes towards EMI were measured. Data were collected using classroom observation, semi-structured interviews and a survey. The results showed that a clear majority of teachers hold negative attitudes towards EMI. The point is that they are linguistically incompetent, and they are not ready yet to deliver content subjects in a language they have no, or little, command of. The study showed the importance of considering attitudes in the ‘policy-formation’ stage before the ‘implementation’ stage. The findings also proved that teachers are not passive bystanders; they can rather be the final arbiters imposing themselves as policy-makers resisting ministerial instructions through their linguistic practices inside the classroom which only acknowledge French. The study showed the necessity to avoid sudden switch and opt for gradual change, without putting aside those who are directly concerned with political/pedagogical measures (teachers, learners, etc).

Keywords: micro planning, EMI, language education policy, agency

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