Search results for: Cement Rotary Kiln
369 Chemical Analysis of Available Portland Cement in Libyan Market Using X-Ray Fluorescence
Authors: M. A. Elbagermia, A. I. Alajtala, M. Alkerzab
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This study compares the quality of different brands of Portland Cement (PC) available in Libyan market. The amounts of chemical constituents like SiO2, Al2O3, Fe2O3, CaO, MgO, SO3 and Lime Saturation Factor (LSF) were determined in accordance with Libyan (L.S.S) and Amrican (A.S.S) Standard Specifications. All the cement studies were found to be good for concrete work especially where no special property is required. The chemical and mineralogical analyses for studied clinker samples show that the dominant phases composition are C3S and C2S while the C3A and C4AF are less abundant.
Keywords: Portland cement, Chemical Composition, Libyan market, X-ray fluorescence.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2890368 Supplementary Cementitious Materials as Sustainable Partial Replacement for Cement in the Building Industry
Authors: Nwakaego C. Onyenokporo
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Cement is the most extensively used construction material due to its strength and versatility of use. However, the production of Portland cement has become unsustainable because of high energy usage, reduction of natural non-renewable resources and emissions of greenhouse gases. Production of cement contributes to anthropogenic greenhouse gases emissions annually. The growing concerns for the environment resulting from this constant and excessive use of cement has therefore raised the need for more green materials and technology. The use of supplementary cementitious materials (SCMs) is considered as one of the many alternatives suited to address this issue and serve as a sustainable partial replacement for cement in construction. This paper will examine the reuse of these waste materials to partially replace Portland cement. It provides a critical review of literature analysing various supplementary cementitious materials which are applicable in the building industry as either partial replacement for cement or aggregates. These materials have been grouped based on source into industrial wastes, domestic/general wastes, and agricultural wastes. The reuse of these waste materials could potentially reduce the negative effects of cement production and reduce landfills which constitute an environmental nuisance. This paper seeks to inform building industry professionals and researchers in the field on the applicability of these waste materials in construction.
Keywords: cement, greenhouse gases, landfills, sustainable, waste materials
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 741367 Supplementary Cementitious Materials as Sustainable Partial Replacement for Cement in the Building Industry
Authors: Nwakaego C. Onyenokporo
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Cement is the most extensively used construction material due to its strength and versatility of use. However, the production of Portland cement has become unsustainable because of high energy usage, reduction of natural non-renewable resources and emissions of greenhouse gases. Production of cement contributes to anthropogenic greenhouse gases emissions annually. The growing concerns for the environment resulting from this constant and excessive use of cement has therefore raised the need for more green materials and technology. The use of supplementary cementitious materials (SCMs) is considered as one of the many alternatives suited to address this issue and serve as a sustainable partial replacement for cement in construction. This paper will examine the reuse of these waste materials to partially replace Portland cement. It provides a critical review of literature analysing various supplementary cementitious materials which are applicable in the building industry as either partial replacement for cement or aggregates. These materials have been grouped based on source into industrial wastes, domestic/general wastes, and agricultural wastes. The reuse of these waste materials could potentially reduce the negative effects of cement production and reduce landfills which constitute an environmental nuisance. This paper seeks to inform building industry professionals and researchers in the field on the applicability of these waste materials in construction.
Keywords: Cement, greenhouse gases, landfills, sustainable, waste materials.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 680366 A Multiple Linear Regression Model to Predict the Price of Cement in Nigeria
Authors: Kenneth M. Oba
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This study investigated factors affecting the price of cement in Nigeria, and developed a mathematical model that can predict future cement prices. Cement is key in the Nigerian construction industry. The changes in price caused by certain factors could affect economic and infrastructural development; hence there is need for proper proactive planning. Secondary data were collected from published information on cement between 2014 and 2019. In addition, questionnaires were sent to some domestic cement retailers in Port Harcourt in Nigeria, to obtain the actual prices of cement between the same periods. The study revealed that the most critical factors affecting the price of cement in Nigeria are inflation rate, population growth rate, and Gross Domestic Product (GDP) growth rate. With the use of data from United Nations, International Monetary Fund, and Central Bank of Nigeria databases, amongst others, a Multiple Linear Regression model was formulated. The model was used to predict the price of cement for 2020-2025. The model was then tested with 95% confidence level, using a two-tailed t-test and an F-test, resulting in an R2 of 0.8428 and R2 (adj.) of 0.6069. The results of the tests and the correlation factors confirm the model to be fit and adequate. This study will equip researchers and stakeholders in the construction industry with information for planning, monitoring, and management of present and future construction projects that involve the use of cement.
Keywords: Cement price, multiple linear regression model, Nigerian Construction Industry, price prediction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 791365 Effect of Nanofibers on the Behavior of Cement Mortar and Concrete
Authors: Mostafa Osman, Ata El-kareim Shoeib
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The main objective of this paper is study the influence of carbon nano-tubes fibers and nano silica fibers on the characteristic compressive strength and flexural strength on concrete and cement mortar. Twelve tested specimens were tested with square section its dimensions (4040 160) mm, divided into four groups. The first and second group studied the effect of carbon nano-tubes (CNTs) fibers with different percentage equal to 0.0, 0.11%, 0.22%, and 0.33% by weight of cement and effect of nano-silica (nS) fibers with different percentages equal to 0.0, 1.0%, 2.0%, and 3.0% by weight of cement on the cement mortar. The third and fourth groups studied the effect of CNTs fiber with different percentage equal to 0.0%, 0.11%, and 0.22% by weight of cement, and effect of nS fibers with different percentages were equal to 0.0%, 1.0%, and 2.0% by weight of cement on the concrete. The compressive strength and flexural strength at 7, 28, and 90 days is determined. From analysis of tested results concluded that the nano-fibers is more effective when used with cement mortar more than used with concrete because of increasing the surface area, decreasing the pore and the collection of nano-fibers. And also by adding nano-fibers the improvement of flexural strength of concrete and cement mortar is more than improvement of compressive strength.
Keywords: Carbon nano-tubes fibers, nano-silica (nS) fibers, compressive strength, flexural.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2719364 Enhancement of Cement Mortar Mechanical Properties with Replacement of Seashell Powder
Authors: Abdoullah Namdar, Fadzil Mat Yahaya
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Many synthetic additives have been using for improve cement mortar and concrete characteristics, but natural additive is a friendly environment option. The quantity of (2% and 4%) seashell powder has been replaced in cement mortar, and compared with plain cement mortar in early age of 7 days. The strain gauges have been installed on beams and cube, for monitoring fluctuation of flexural and compressive strength. Main objective of this paper is to study effect of linear static force on flexural and compressive strength of modified cement mortar. The results have been indicated that the replacement of appropriate proportion of seashell powder enhances cement mortar mechanical properties. The replacement of 2% seashell causes improvement of deflection, time to failure and maximum load to failure on concrete beam and cube, the same occurs for compressive modulus elasticity. Increase replacement of seashell to 4% reduces all flexural strength, compressive strength and strain of cement mortar.
Keywords: Compressive strength, flexural strength, compressive modulus elasticity, time to failure, deflection.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3450363 Mechanical Properties of Cement Slurry by Partially Substitution of Industry Waste Natural Pozzolans
Authors: R. Ziaie Moayed, S. P. Emadoleslami Oskoei, S. D. Beladi Mousavi, A. Taleb Beydokhti
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There have been many reports of the destructive effects of cement on the environment in recent years. In the present research, it has been attempted to reduce the destructive effects of cement by replacing silica fume as adhesive materials instead of cement. The present study has attempted to improve the mechanical properties of cement slurry by using waste material from a glass production factory, located in Qazvin city of Iran, in which accumulation volume has become an environmental threat. The chemical analysis of the waste material indicates that this material contains about 94% of SiO2 and AL2O3 and has a close structure to silica fume. Also, the particle grain size test was performed on the mentioned waste. Then, the unconfined compressive strength test of the slurry was performed by preparing a mixture of water and adhesives with different percentages of cement and silica fume. The water to an adhesive ratio of this mixture is 1:3, and the curing process last 28 days. It was found that the sample had an unconfined compressive strength of about 300 kg/cm2 in a mixture with equal proportions of cement and silica fume. Besides, the sample had a brittle fracture in the slurry sample made of pure cement, however, the fracture in cement-silica fume slurry mixture is flexible and the structure of the specimen remains coherent after fracture. Therefore, considering the flexibility that is achieved by replacing this waste, it can be used to stabilize soils with cracking potential.
Keywords: Cement replacement, cement slurry, environmental threat, natural pozzolan, silica fume, waste material.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 671362 Mechanical Properties of Hybrid Cement Based Mortars Containing Two Biopolymers
Authors: Z. Abdollahnejad, M. Kheradmand, F. Pacheco-Torgal
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The use of bio-based admixtures on construction materials is a recent trend that is gaining momentum. However, to our knowledge, no studies have been reported concerning the use of biopolymers on hybrid cement based mortars. This paper reports experimental results regarding the study of the influence of mix design of 43 hybrid cement mortars containing two different biopolymers on its mechanical performance. The results show that the use of the biopolymer carrageenan is much more effective than the biopolymer xanthan concerning the increase in compressive strength. An optimum biopolymer content was found.Keywords: Waste reuse, fly ash, waste glass, hybrid cement, biopolymers, mechanical strength.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1019361 Effect of Bentonite on the Rheological Behavior of Cement Grout in Presence of Superplasticizer
Authors: K. Benyounes, A. Benmounah
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Cement-based grouts has been used successfully to repair cracks in many concrete structures such as bridges, tunnels, buildings and to consolidate soils or rock foundations. In the present study the rheological characterization of cement grout with water/binder ratio (W/B) is fixed at 0.5. The effect of the replacement of cement by bentonite (2 to 10% wt) in presence of superplasticizer (0.5% wt) was investigated. Several rheological tests were carried out by using controlled-stress rheometer equipped with vane geometry in temperature of 20°C. To highlight the influence of bentonite and superplasticizer on the rheological behavior of grout cement, various flow tests in a range of shear rate from 0 to 200 s-1 were observed. Cement grout showed a non-Newtonian viscosity behavior at all concentrations of bentonite. Three parameter model Herschel- Bulkley was chosen for fitting of experimental data. Based on the values of correlation coefficients of the estimated parameters, The Herschel-Bulkley law model well described the rheological behavior of the grouts. Test results showed that the dosage of bentonite increases the viscosity and yield stress of the system and introduces more thixotropy. While the addition of both bentonite and superplasticizer with cement grout improve significantly the fluidity and reduced the yield stress due to the action of dispersion of SP.
Keywords: Cement grout, bentonite, superplasticizer, viscosity, yield stress.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3566360 Effect of Fine-Ground Ceramic Admixture on Early Age Properties of Cement Paste
Authors: Z. Pavlík, M. Pavlíková, P. Volfová, M. Keppert, R. Černý
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Properties of cement pastes with fine-ground ceramics used as an alternative binder replacing Portland cement up to 20% of its mass are investigated. At first, the particle size distribution of cement and fine-ground ceramics is measured using laser analyser. Then, the material properties are studied in the early hardening period up to 28 days. The hydration process of studied materials is monitored by electrical conductivity measurement using TDR sensors. The changes of materials- structures within the hardening are observed using pore size distribution measurement. The compressive strength measurements are done as well. Experimental results show that the replacement of Portland cement by fine-ground ceramics in the amount of up to 20% by mass is acceptable solution from the mechanical point of view. One can also assume similar physical properties of designed materials to the reference material with only Portland cement as binder.Keywords: Fine-ground ceramics, cement pastes, early age properties, mechanical properties, pore size distribution, electrical conductivity measurement.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1594359 Simulation of a Sustainable Cement Supply Chain; Proposal Model Review
Authors: Tarek Elhasia, Bernd Noche, Lima Zhao
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In recent years, sustainable supply chain management (SSCM) has been widely researched in academic domain. However, due to the traditional operational role and the complexity of supply chain management in the cement industry, a relatively small amount of research has been conducted on cement supply chain simulation integrated with sustainability criteria. This paper analyses the cement supply chain operations using the Push-Pull supply chain frameworks, the Life Cycle Assessment (LCA) methodology; and proposal integration approach, proposes three supply chain scenarios based on Make-To-Stock (MTS), Pack-To-Order (PTO) and Grind- To-Order (GTO) strategies. A Discrete-Event Simulation (DES) model of SSCM is constructed using Arena software to implement the three-target scenarios. We conclude with the simulation results that (GTO) is the optimal supply chain strategy that demonstrates the best economic, ecological and social performance in the cement industry.Keywords: Cement industry, simulation, supply chain management (SCM), sustainability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6968358 An investigation on the Effect of Continuous Phase Height on the First and Second Critical Rotor Speeds in a Rotary Disc Contactor
Authors: Hoda Molavi, Sima Hoseinpoor, Hossein Bahmanyar
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A Rotary Disc Contactor with inner diameter of 9.1cm and maximum operating height of 40cm has been used to investigate break up phenomenon. Water-Toluene, Water as continuous phase and Toluene as dispersed phase, was selected as chemical system in the experiments. The mentioned chemical system has high interfacial tension so it was possible to form big drops which permit accurate investigation on break up phenomenon as well as the first and second critical rotor speeds. In this study, Break up phenomenon has been studied as a function of mother drop size, rotor speed and continuous phase height. Further more; the effects of mother drop size and continuous phase height on the first and second critical rotor speeds were investigated. Finally, two modified correlations were proposed to estimate the first and second critical speeds.Keywords: Breakage, First critical rotor speed, Rotary disccontactor, Second critical rotor speed
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1425357 Microstructure and Mechanical Behaviuor of Rotary Friction Welded Titanium Alloys
Authors: M. Avinash, G. V. K. Chaitanya, Dhananjay Kumar Giri, Sarala Upadhya, B. K. Muralidhara
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Ti-6Al-4V alloy has demonstrated a high strength to weight ratio as well as good properties at high temperature. The successful application of the alloy in some important areas depends on suitable joining techniques. Friction welding has many advantageous features to be chosen for joining Titanium alloys. The present work investigates the feasibility of producing similar metal joints of this Titanium alloy by rotary friction welding method. The joints are produced at three different speeds and the performances of the welded joints are evaluated by conducting microstructure studies, Vickers Hardness and tensile tests at the joints. It is found that the weld joints produced are sound and the ductile fractures in the tensile weld specimens occur at locations away from the welded joints. It is also found that a rotational speed of 1500 RPM can produce a very good weld, with other parameters kept constant.Keywords: Rotary friction weld, rotational speed, Ti-6Al-4V, weld structures.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2606356 Role of Dispersion of Multiwalled Carbon Nanotubes on Compressive Strength of Cement Paste
Authors: Jyoti Bharj, Sarabjit Singh, Subhash Chander, Rabinder Singh
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The outstanding mechanical properties of Carbon nanotubes (CNTs) have generated great interest for their potential as reinforcements in high performance cementitious composites. The main challenge in research is the proper dispersion of carbon nanotubes in the cement matrix. The present work discusses the role of dispersion of multiwalled carbon nanotubes (MWCNTs) on the compressive strength characteristics of hydrated Portland IS 1489 cement paste. Cement-MWCNT composites with different mixing techniques were prepared by adding 0.2% (by weight) of MWCNTs to Portland IS 1489 cement. Rectangle specimens of size approximately 40mm × 40mm ×160mm were prepared and curing of samples was done for 7, 14, 28 and 35days. An appreciable increase in compressive strength with both techniques; mixture of MWCNTs with cement in powder form and mixture of MWCNTs with cement in hydrated form 7 to 28 days of curing time for all the samples was observed.
Keywords: Carbon Nanotubes, Portland Cement, Composite, Compressive Strength.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3135355 Effect on Surface Temperature Reduction of Asphalt Pavements with Cement–Based Materials Containing Ceramic Waste Powder
Authors: H. Higashiyama, M. Sano, F. Nakanishi, M. Sugiyama, O. Takahashi, S. Tsukuma
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The heat island phenomenon becomes one of the environmental problems. As countermeasures in the field of road engineering, cool pavements such as water retaining pavements and solar radiation reflective pavements have been developed to reduce the surface temperature of asphalt pavements in the hot summer climate in Japan. The authors have studied on the water retaining pavements with cement–based grouting materials. The cement–based grouting materials consist of cement, ceramic waste powder, and natural zeolite. The ceramic waste powder is collected through the recycling process of electric porcelain insulators. In this study, mixing ratio between the ceramic waste powder and the natural zeolite and a type of cement for the cement–based grouting materials is investigated to measure the surface temperature of asphalt pavements in the outdoor. All of the developed cement–based grouting materials were confirmed to effectively reduce the surface temperature of the asphalt pavements. Especially, the cement–based grouting material using the ultra–rapid hardening cement with the mixing ratio of 0.7:0.3 between the ceramic waste powder and the natural zeolite reduced mostly the surface temperature by 20 °C and more.Keywords: Ceramic waste powder, natural zeolite, road surface temperature, water retaining pavements.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1705354 Effect of Addition the Dune Sand Powder on Development of Compressive Strength and Hydration of Cement Pastes
Authors: S. Guettala, B. Mezghiche
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In this paper, the effect of addition the dune sand powder (DSP) on development of compressive strength and hydration of cement pastes was investigated as a function of water/binder ratio, was varied, on the one hand, the percentage of DSP and on the other, the fineness of DSP. In order to understand better the pozzolanic effect of dune sand powder in cement pastes, we followed the mixtures hydration (50% Pure Lime + 50% DSP) by X-ray diffraction. These mixtures the pastes present a hydraulic setting which is due to the formation of a C-S-H phase (calcium silicate hydrate). The latter is semi-crystallized. This study is a simplified approach to that of the mixtures (80% ordinary Portland cement + 20% DSP), in which the main reaction is the fixing of the lime coming from the cement hydration in the presence of DSP, to form calcium silicate hydrate semi-crystallized of second generation. The results proved that up to (20% DSP) as Portland cement replacement could be used with a fineness of 4000 cm²/g without affecting adversely the compressive strength. After 28 days, the compressive strength at 5, 10 and 15% DSP is superior to Portland cement, with an optimum effect for a percentage of the order of 5% to 10% irrespective of the w/b ratio and fineness of DSP.
Keywords: Ordinary Portland Cement, Pure Lime, Dune Sand Powder, Compressive Strength, Hydration.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2112353 Resistance to Sulfuric Acid Attacks of Self-Consolidating Concrete: Effect Metakaolin and Various Cements Types
Authors: Kianoosh Samimi, Farhad Estakhr, Mahdi Mahdikhani, Faramaz Moodi
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Due to their fluidity and simplicity of use, self-compacting concretes (SCCs) have undeniable advantages. In recent years, the role of metakaolin as a one of pozzolanic materials in concrete has been considered by researchers. It can modify various properties of concrete, due to high pozzolanic reactions and also makes a denser microstructure. The objective of this paper is to examine the influence of three type of Portland cement and metakaolin on fresh state, compressive strength and sulfuric acid attacks in self- consolidating concrete at early age up to 90 days of curing in lime water. Six concrete mixtures were prepared with three types of different cement as Portland cement type II, Portland Slag Cement (PSC), Pozzolanic Portland Cement (PPC) and 15% substitution of metakaolin by every cement. The results show that the metakaolin admixture increases the viscosity and the demand amount of superplasticizer. According to the compressive strength results, the highest value of compressive strength was achieved for PSC and without any metakaolin at age of 90 days. Conversely, the lowest level of compressive strength at all ages of conservation was obtained for PPC and containing 15% metakaolin. According to this study, the total substitution of PSC and PPC by Portland cement type II is beneficial to the increasing in the chemical resistance of the SCC with respect to the sulfuric acid attack. On the other hand, this increase is more noticeable by the use of 15% of metakaolin. Therefore, it can be concluded that metakaolin has a positive effect on the chemical resistance of SCC containing of Portland cement type II, PSC, and PPC.
Keywords: SCC, metakaolin, cement type, durability, compressive strength, sulfuric acid attacks.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 895352 Optimization of Transportation Cost of Plaster of Paris Cement
Authors: K. M. Oba
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The transportation modelling technique was adopted in the solution of the problem of transportation of Plaster of Paris (POP) cement from three supply locations (construction materials markets) to three demand locations (construction sites) in Port Harcourt. The study was carried out for 40 kg bags of POP cement fully loaded on 600 bags per truck from the three selected construction materials markets in Port Harcourt. The costs of transporting the POP cement were determined and subjected to the North-West Corner, Least Cost, and Vogel’s approximation methods to determine the initial feasible solution. Of the three results, the Least Cost Method turned out to have the lowest cost. Using the Stepping Stone Method, the optimum shipping cost was finally attained after two successive iterations. The optimum shipping cost was calculated to be $1,690 or ₦1,774,500 as of October 2023. As a result of this study, the application of transportation modelling can boost the effective management of the transportation of POP cement in construction projects.
Keywords: Cost of POP cement, management of transportation, optimization of shipping cost, Plaster of Paris, transportation model.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 268351 The Flexural Strength of Fiber-Reinforced Polymer Cement Mortars Using UM Resin
Authors: Min Ho Kwon, Woo Young Jung, Hyun Su Seo
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A polymer cement mortar (PCM) has been widely used as the material of repair and restoration work for concrete structure; however a PCM usually induces an environmental pollutant. Therefore, there is a need to develop PCM which is less impact to environments. Usually, UM resin is known to be harmless to the environment. Accordingly, in this paper, the properties of the PCM using UM resin were studied. The general cement mortar and UM resin were mixed in the specified ratio. A certain percentage of PVA fibers, steel fibers and mixed fibers (PVA fiber and steel fiber) were added to enhance the flexural strength. The flexural tests were performed in order to investigate the flexural strength of each PCM. Experimental results showed that the strength of proposed PCM using UM resin is improved when they are compared with general cement mortar.
Keywords: Polymer cement mortar (PCM), UM resin, Compressive strength, PVA fiber, Steel fiber.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3291350 Some Mechanical Properties of Cement Stabilized Malaysian Soft Clay
Authors: Meei-Hoan Ho, Chee-Ming Chan
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Soft clays are defined as cohesive soil whose water content is higher than its liquid limits. Thus, soil-cement mixing is adopted to improve the ground conditions by enhancing the strength and deformation characteristics of the soft clays. For the above mentioned reasons, a series of laboratory tests were carried out to study some fundamental mechanical properties of cement stabilized soft clay. The test specimens were prepared by varying the portion of ordinary Portland cement to the soft clay sample retrieved from the test site of RECESS (Research Centre for Soft Soil). Comparisons were made for both homogeneous and columnar system specimens by relating the effects of cement stabilized clay of for 0, 5 and 10 % cement and curing for 3, 28 and 56 days. The mechanical properties examined included one-dimensional compressibility and undrained shear strength. For the mechanical properties, both homogeneous and columnar system specimens were prepared to examine the effect of different cement contents and curing periods on the stabilized soil. The one-dimensional compressibility test was conducted using an oedometer, while a direct shear box was used for measuring the undrained shear strength. The higher the value of cement content, the greater is the enhancement of the yield stress and the decrease of compression index. The value of cement content in a specimen is a more active parameter than the curing period.Keywords: Soft soil, Oedometer, Direct shear box, Cementstabilisedcolumn.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3247349 Comparative Sulphate Resistance of Pozzolanic Cement Mortars
Authors: Mahmud Abba Tahir
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This is report on experiment out to compare the sulphate resistance of sand mortar made with five different pozzolanic cement. The pozzolanic cement were prepared by blending powered burnt bricks from the Adamawa, Makurdi, Kano, Kaduna and Niger bricks factories with ordinary Portland cement in the ratio 1:4. Sand –pozzolanic cement mortars of mix ratio 1:6 and 1:3 with water-cement ratio of 0.65 and 0.40 respectively were used to prepare cubes and bars specimens. 150 mortar cubes of size 70mm x 70mm x 70mm and 35 mortar bars of 15mm x 15mm x 100mm dimensions were cast and cured for 28 days. The cured specimens then immersed in the solutions of K2SO4, (NH4)2SO4 and water for 28 days and then tested. The compressive strengths of cubes in water increased by 34% while those in the sulphate solutions decreased. Strength decreases of the cubes, cracking and warping of bars immersed in K2SO4 were less than those in (NH4)2SO4. Specimens made with Niger and Makurdi pulverized burnt bricks experienced less effect of the sulphates and can therefore be used as pozzolan in mortar and concrete to resist sulphate.
Keywords: Burnt bricks powder, comparative, pozzolanic cement, sulphates.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 850348 A Review on 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 is 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. In the construction industry, the utilization of recycled materials plays a significant role in environmental conservation, and a thorough investigation into these materials could potentially yield substantial economic benefits if appropriately harnessed.
Keywords: Paper waste, rice grain husks, recycled materials, waste management.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 238347 Advanced Model for Calculation of the Neutral Axis Shifting and the Wall Thickness Distribution in Rotary Draw Bending Processes
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Rotary draw bending is a method which is being used in tube forming. In the tube bending process, the neutral axis moves towards the inner arc and the wall thickness distribution changes for tube’s cross section. Thinning takes place in the outer arc of the tube (extrados) due to the stretching of the material, whereas thickening occurs in the inner arc of the tube (intrados) due to the comparison of the material. The calculations of the wall thickness distribution, neutral axis shifting, and strain distribution have not been accurate enough, so far. The previous model (the geometrical model) describes the neutral axis shifting and wall thickness distribution. The geometrical of the tube, bending radius and bending angle are considered in the geometrical model, while the influence of the material properties of the tube forming are ignored. The advanced model is a modification of the previous model using material properties that depends on the correction factor. The correction factor is a purely empirically determined factor. The advanced model was compared with the Finite element simulation (FE simulation) using a different bending factor (Bf =bending radius/ diameter of the tube), wall thickness (Wf = diameter of the tube/ wall thickness), and material properties (strain hardening exponent). Finite element model of rotary draw bending has been performed in PAM-TUBE program (version: 2012). Results from the advanced model resemble the FE simulation and the experimental test.
Keywords: Rotary draw bending, material properties, neutral axis shifting, wall thickness distribution.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3917346 Relation between Properties of Internally Cured Concrete and Water Cement Ratio
Authors: T. Manzur, S. Iffat, M. A. Noor
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In this paper, relationship between different properties of IC concrete and water cement ratio, obtained from a comprehensive experiment conducted on IC using local materials (Burnt clay chips- BC) is presented. In addition, saturated SAP was used as an IC material in some cases. Relationships have been developed through regression analysis. The focus of this analysis is on developing relationship between a dependent variable and an independent variable. Different percent replacements of BC and water cement ratios were used. Compressive strength, modulus of elasticity, water permeability and chloride permeability were tested and variations of these parameters were analyzed with respect to water cement ratio.Keywords: Compressive strength, concrete, curing, lightweight, aggregate, superabsorbent polymer, internal curing.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2445345 Performance of Ground Clay Bricks as Partial Cement Replacement in Grade 30 Concrete
Authors: Kartini, K., Rohaidah, M.N., Zuraini, ZA.
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Demolitions of buildings have created a lot of waste and one of it is clay bricks. The waste clay bricks were ground to roughly cement fineness and used to partially replaced cement at 10%, 20% and 30% with w/b ratio of 0.6 and tested at 7, 28, 60, 90 and 120 days. The result shows that the compressive strength of GCB concrete increases over age however, decreases as the level of replacements increases. It was also found that 10% replacement of GCB gave the highest compressive strength, however for optimum replacement, 30% was chosen as it still attained strength of grade 30 concrete. In terms of durability performances, results show that GCB replacement up to 30% was found to be efficient in reducing water absorption as well as water permeability. These studies show that GCB has the potential to be used as partial cement replacement in making concrete.Keywords: Compressive Strength, Ground Clay Bricks, Partial Cement Replacement, Water Absorption and Permeability
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3106344 Some Characteristics and Identification of Fungi Contaminated by Alkomos Cement Factory
Authors: Abdulmajeed Bashir Mlitan, Ethan Hack
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Soil samples were collected from and around Alkomos cement factory, Alkomos town, Libya. Soil physiochemical properties were determined. In addition, olive leaves were scanned for their fungal content. This work can conclude that the results obtained for the examined physiochemical characteristics of soil in the area studied prove that cement dust from the Alkomos cement factory in Libya has had a significant impact on the soil. The affected soil properties are pH and total calcium content. These characteristics were found to be higher than those in similar soils from the same area. The increment of soil pH in the same area may be a result of precipitation of cement dust over the years. Different responses were found in each season and each site. For instance, the dominance of fungi of soil and leaves was lowest at 100 m from the factory and the evenness and diversity increased at this site compared to the control area and 250 m from the factory.Keywords: Pollution, Soil Microbial, Alkomos, Libya.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1327343 A Composite Developed from a Methyl Methacrylate and Embedded Eppawala Hydroxyapatite for Orthopedics
Authors: H. K. G. K. D. K. Hapuhinna, R. D. Gunaratne, H. M. J. C. Pitawala
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This study aimed to find out chemical and structural suitability of synthesized eppawala hydroxyapatite composite as bone cement, by comparing and contrasting it with human bone as well as commercially available bone cement, which is currently used in orthopedic surgeries. Therefore, a mixture of commercially available bone cement and its liquid monomer, commercially available methyl methacrylate (MMA) and a mixture of solid state synthesized eppawala hydroxyapatite powder with commercially available MMA were prepared as the direct substitution for bone cement. Then physical and chemical properties including composition, crystallinity, presence of functional groups, thermal stability, surface morphology, and microstructural features were examined compared to human bone. Results show that there is a close similarity between synthesized product and human bone and it has exhibited high thermal stability, good crystalline and porous properties than the commercial product. Finally, the study concluded that synthesized hydroxyapatite composite can be used directly as a substitution for commercial bone cement.
Keywords: Hydroxyapatite, bone cement, methyl methacrylate, orthopedics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 624342 Possibilities of Utilization Zeolite in Concrete
Authors: M. Sedlmajer, J. Zach, J. Hroudová, P. Rovnaníková
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There are several possibilities of reducing the required amount of cement in concrete production. Natural zeolite is one of the raw materials which can partly substitute Portland cement. The effort to reduce the amount of Portland cement used in concrete production is brings both economical as well as ecological benefits. The paper presents the properties of concrete containing natural zeolite as an active admixture in the concrete which partly substitutes Portland cement. The properties discussed here bring information about the basic mechanical properties and frost resistance of concrete containing zeolite. The properties of concretes with the admixture of zeolite are compared with a reference concrete with no content of zeolite. The properties of the individual concretes are observed for 360 days.
Keywords: Concrete, zeolite, compressive strength, modulus of elasticity, durability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2927341 Chromium-Leaching Study of Cements in Various Environments
Authors: Adriana Estokova, Lenka Palascakova, Martina Kovalcikova
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Cement is a basic material used for building construction. Chromium as an indelible non-volatile trace element of raw materials occurs in cement clinker in the trivalent or hexavalent form. Hexavalent form of chromium is harmful and allergenic having very high water solubility and thus can easily come into contact with the human skin. The paper is aimed at analyzing the content of total chromium in Portland cements and leaching rate of hexavalent chromium in various leachants: Deionized water, Britton-Robinson buffer, used to simulate the natural environment, and hydrochloric acid (HCl). The concentration of total chromium in Portland cement samples was in a range from 173.2 to 218.5 mg/kg. The content of dissolved hexavalent chromium ranged 0.23-3.19, 2.0-5.78 and 8.88-16.25 mg/kg in deionized water, Britton-Robinson solution and hydrochloric acid, respectively. The calculated leachable fraction of Cr(VI) from cement samples was observed in the range 0.1--7.58 %.
Keywords: Cement, hexavalent chromium, leaching, total chromium.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1339340 Characterization of Cement Mortar Based on Fine Quartz
Authors: K. Arroudj, M. Lanez, M. N. Oudjit
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The introduction of siliceous mineral additions in cement production allows, in addition to the ecological and economic gain, improvement of concrete performance. This improvement is mainly due to the fixing of Portlandite, released during the hydration of cement, by fine siliceous, forming denser calcium silicate hydrates and therefore a more compact cementitious matrix. This research is part of the valuation of the Dune Sand (DS) in the cement industry in Algeria. The high silica content of DS motivated us to study its effect, at ground state, on the properties of mortars in fresh and hardened state. For this purpose, cement pastes and mortars based on ground dune sand (fine quartz) has been analyzed with a replacement to cement of 15%, 20% and 25%. This substitution has reduced the amount of heat of hydration and avoids any risk of initial cracking. In addition, the grinding of the dune sand provides amorphous thin populations adsorbed at the surface of the crystal particles of quartz. Which gives to ground quartz pozzolanic character. This character results an improvement of mechanical strength of mortar (66 MPa in the presence of 25% of ground quartz).
Keywords: Mineralogical structure, Pozzolanic reactivity, quartz, mechanical strength.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1016