scholarly journals Evaluation of Lime-Treated Lateritic Soil for Reservoir Shoreline Stabilization

Water ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3141
Author(s):  
Ricardo Moreira Vilhena ◽  
Márcia Maria dos Anjos Mascarenha ◽  
Renato Resende Angelim ◽  
Tomás da Rosa Simões ◽  
Renato Batista de Oliveira ◽  
...  
Keyword(s):  
Hydrated Lime ◽  
Lateritic Soil ◽  
Curing Time ◽  
Content Type ◽  
Shoreline Stabilization ◽  
Weight Percentage ◽  
Wave Flume ◽  
Lime Content ◽  
Lateritic Clay ◽  
Lime Solution

Sedimentation is one of the major problems addressed by reservoir management, and requires extensive effort to control it. This paper aims to evaluate the efficiency of the soil–lime stabilization technique for reservoir shores. The treatment consisted of spraying hydrated lime in slurry form over the surface of a lateritic clay sample with 1, 2, and 4% lime solution and curing times of 1, 7, 28, and 56 days with air-drying and moist-room storage. In addition, a single test with less than 1% lime solution by weight percentage was carried out. The post-cured specimens were mapped with SEM and X-ray analyses. A wave flume test was performed in samples subjected to diverse conditions of lime content, type, and curing time. The results showed that the present technique produces a Ca-rich crust by carbonation rather than stabilizing it and that the lime content and type of curing generate improvements in soil loss reduction, but the curing time does not. The technique gave relative protection against water level variation and wave impacts, but it is necessary to consider a frequent application of lime on the lateritic soil.

Effect of hydrated lime on efflorescence formation

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Diogo Henrique de Bem ◽  
Priscila Ongaratto Trentin ◽  
Ronaldo A. Medeiros-Junior
Keyword(s):  
Compressive Strength ◽  
Portland Cement ◽  
Design Methodology ◽  
Hydrated Lime ◽  
Content Type ◽  
Mercury Intrusion ◽  
Lime Content ◽  
Cement Mortars ◽  
Cement Based Materials ◽  
Historical Heritage

PurposeEfflorescence formation is very common in cement-based materials. In the case of mortar, efflorescence is more studied when only Portland cement is used as a binder. However, the repair of historical heritage, as well as the construction system of some countries, usually uses mortars composed of hydrated lime and Portland cement. This study aims to determine the influence of the hydrated lime content on the incidence of efflorescence in mortars.Design/methodology/approachMortars with 0%, 50%, and 100% lime/cement ratio were studied, using three different methods to accelerate efflorescence formation. The surface area of mortars affected by efflorescence was quantified by analysis using image software. Also, analysis of mercury intrusion porosity test, flexural tensile, compressive strength, absorption of water by capillarity, porosity, XRD and TGA was performed.FindingsMore efflorescence in mortars with a higher amount of lime in their composition was observed. The results show that the increase in the lime content reduces the flexural tensile and the compressive strength and increased the absorption of water by capillarity and the porosity of the mortars. The material formed by the efflorescence was calcium carbonate, proven by microstructural tests.Originality/valueThe results of greater efflorescence formation in mortars with lime are important to alert users who apply this type of material. Some type of protection must be done more rigorously for lime-cement mortars, especially concerning contact with water, since efflorescence tends to be faster for this type of material.

Fluid-structure interaction computational analysis and experiments of tsunami bore forces on coastal bridges

2021 ◽  
Vol 31 (5) ◽  
pp. 1373-1395
Author(s):  
Iman Mazinani ◽  
Mohammad Mohsen Sarafraz ◽  
Zubaidah Ismail ◽  
Ahmad Mustafa Hashim ◽  
Mohammad Reza Safaei ◽  
...  
Keyword(s):  
Tsunami Wave ◽  
Numerical Study ◽  
Fluid Structure Interaction ◽  
Indian Ocean Tsunami ◽  
Fluid Structure ◽  
Content Type ◽  
Coastal Bridges ◽  
Structure Interaction ◽  
Wave Flume ◽  
Wave Heights

Purpose Two disastrous Tsunamis, one on the west coast of Sumatra Island, Indonesia, in 2004 and another in North East Japan in 2011, had seriously destroyed a large number of bridges. Thus, experimental tests in a wave flume and a fluid structure interaction (FSI) analysis were constructed to gain insight into tsunami bore force on coastal bridges. Design/methodology/approach Various wave heights and shallow water were used in the experiments and computational process. A 1:40 scaled concrete bridge model was placed in mild beach profile similar to a 24 × 1.5 × 2 m wave flume for the experimental investigation. An Arbitrary Lagrange Euler formulation for the propagation of tsunami solitary and bore waves by an FSI package of LS-DYNA on high-performance computing system was used to evaluate the experimental results. Findings The excellent agreement between experiments and computational simulation is shown in results. The results showed that the fully coupled FSI models could capture the tsunami wave force accurately for all ranges of wave heights and shallow depths. The effects of the overturning moment, horizontal, uplift and impact forces on a pier and deck of the bridge were evaluated in this research. Originality/value Photos and videos captured during the Indian Ocean tsunami in 2004 and the 2011 Japan tsunami showed solitary tsunami waves breaking offshore, along with an extremely turbulent tsunami-induced bore propagating toward shore with significantly higher velocity. Consequently, the outcomes of this current experimental and numerical study are highly relevant to the evaluation of tsunami bore forces on the coastal, over sea or river bridges. These experiments assessed tsunami wave forces on deck pier showing the complete response of the coastal bridge over water.

scholarly journals CO2 and cost optimization of reinforced concrete footings over a lime-treated soil using modified simulated annealing algorithm

Inge CUC ◽  
2020 ◽  
Vol 16 (1) ◽  
Author(s):  
Jair De Jesús Arrieta Baldovino ◽  
Carlos Millán Páramo ◽  
Ronaldo Luis Dos Santos Izzo ◽  
Eclesielter Moreira
Keyword(s):  
Simulated Annealing ◽  
Co2 Emissions ◽  
Simulated Annealing Algorithm ◽  
Friction Angle ◽  
Curing Time ◽  
Design Constraint ◽  
Treated Soil ◽  
Lime Content ◽  
Spread Footings ◽  
Annealing Algorithm

Introduction: The design of spread footings over a lime-treated soil is studied as an important topic in geotechnical and environmental engineering. With the emergence and use of algorithms, it is possible to solve optimization problems in engineering, leading, for example, to decreased amounts of materials, time, energy, and work. Objective: This research aims to optimize the CO2 emission and cost of building spread footings over a treated soil with hydrated lime using the modified simulated annealing algorithm (MSAA). Method: The parameters for shear strength (cohesion and friction angle) was calculated of a silty soil of the Guabirotuba geological formation of Curitiba (Brazil) stabilized with different lime contents (3, 5, 7 and 9%) at different curing times (30, 90, and 180 days). Then with these parameters, the geometry of the spread footings was optimized with MSAA minimizing the cost and CO2 emissions of their construction. For the design constraint of the structures the ultimate bearing capacity of the soil was used as criteria, the settlements produced by the service load, and the base safety factor Results: The results show that most of the problems converge to the same solution for costs and CO2 emissions without depending on curing time and lime content used, due to the solutions being restricted primarily by the maximum permissible settlements. Conclusions: With the increase in lime content, the cohesion of the mixtures increased for all curing times studied ant the friction angle had no major variations in relation to the amount of lime administered or to the curing time employed. Costs and carbon dioxide emissions for spread footing construction converge to the same results. In this sense, 9% lime can be avoided, and small percentages of lime (i.e. 3-5%) are appropriated to ground improvement and reduce the costs of this procedure. On the other hand, the MSAA can be designated as a robust algorithm due to having achieved almost equal results and, in some cases, better results compared with other algorithms to solve problems reported in the literature.

Study on the effect of hydrated lime content and fineness on asphalt properties

2020 ◽  
Vol 244 ◽  
pp. 118379
Author(s):  
Sen Han ◽  
Shihao Dong ◽  
Yuanyuan Yin ◽  
Mengmei Liu ◽  
Yamin Liu
Keyword(s):  
Hydrated Lime ◽  
Lime Content

Effects of nano-copper particles on the properties of Sn58Bi composite solder pastes

2017 ◽  
Vol 34 (1) ◽  
pp. 40-44 ◽  
Author(s):  
Hao Zhang ◽  
Yang Liu ◽  
Fenglian Sun ◽  
Gaofang Ban ◽  
Jiajie Fan
Keyword(s):  
Formation Mechanism ◽  
Composite Solder ◽  
Defect Formation ◽  
Void Formation ◽  
Experimental Results ◽  
Solder Paste ◽  
Content Type ◽  
Weight Percentage ◽  
Copper Particles ◽  
Solder Pastes

Purpose This paper aimed to investigate the effects of nano-copper particles on the melting behaviors, wettability and defect formation mechanism of the Sn58Bi composite solder pastes. Design/methodology/approach In this paper, the mechanical stirring method was used to get the nano-composite solder pastes. Findings Experimental results indicated that the addition of 3 wt.% (weight percentage) 50 nm copper particles showed limited effects on the melting behaviors of the Sn58Bi composite solder paste. The spreading rate of the Sn58Bi composite solder paste showed a decreasing trend with the increase of the weight percentage of 50 nm copper particles from 0 to 3 wt.%. With the addition of copper particles of diameters 50 nm, 500 nm or 6.5 μm into the Sn58Bi solder paste, the porosities of the three types of solder pastes showed a similar trend. The porosity increased with the increase of the weight percentage of copper particles. Based on the experimental results, a model of the void formation mechanism was proposed. During reflow, the copper particles reacted with Sn in the matrix and formed intermetallic compounds, which gathered around the voids produced by the volatilization of flux. The exclusion of the voids was suppressed and eventually led to the formation of defects. Originality/value This study provides an optimized material for the second and third level packaging. A model of the void formation mechanism was proposed.

Tribological behavior of AA7075-TiC composites by powder metallurgy

2018 ◽  
Vol 70 (6) ◽  
pp. 1066-1071 ◽  
Author(s):  
Saravanan C. ◽  
Subramanian K. ◽  
Anandakrishnan V. ◽  
Sathish S.
Keyword(s):  
Powder Metallurgy ◽  
Metal Matrix Composites ◽  
Metal Matrix ◽  
Tribological Behavior ◽  
Wear Behavior ◽  
Process Condition ◽  
Wear Test ◽  
Matrix Composites ◽  
Content Type ◽  
Weight Percentage

Purpose Aluminium is the most preferred material in engineering structural components because of its excellent properties. Furthermore, the properties of aluminium may be enhanced through metal matrix composites and an in-depth investigation on the evolved properties is needed in view of metallurgical, mechanical and tribological aspects. The purpose of this study is to explore the effect of TiC addition on the tribological behavior of aluminium composites. Design/methodology/approach Aluminium metal matrix composites at different weight percentage of titanium carbide were produced through powder metallurgy. Produced composites were subjected to sliding wear test under dry condition through Taguchi’s L9 orthogonal design. Findings Optimal process condition to achieve the minimum wear rate was identified though the main effect plot. Sliding velocity was identified as the most dominating factor in the wear resistance. Practical implications The production of components with improved properties is promoted efficiently and economically by synthesizing the composite via powder metallurgy. Originality/value Though the investigations on the wear behavior of aluminium composites are analyzed, reinforcement types and the mode of fabrication have their significance in the metallurgical and mechanical properties. Thus, the produced component needs an in-detail study on the property evolution.

scholarly journals Effect of Hydrated Lime on Indirect Tensile Stiffness Modulus of Asphalt Concrete Produced in Half-Warm Mix Technology

Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4731
Author(s):  
Mateusz M. Iwański
Keyword(s):  
Asphalt Concrete ◽  
Permanent Deformation ◽  
Active Agent ◽  
Hydrated Lime ◽  
Partial Replacement ◽  
Stiffness Modulus ◽  
Limestone Filler ◽  
Tensile Stiffness ◽  
Lime Content ◽  
Indirect Tensile

Half-warm mix asphalt (HWMA) mixtures can be produced at temperatures ranging from 100 °C to 130 °C, depending on the production methods used. The lowest mixing temperature can be achieved by using water-foamed bitumen. The mixture should be characterized by a long service life, defined by the resistance to permanent deformation and high stiffness modulus at temperatures above zero. It is therefore important to ensure the adequately high quality of the bitumen binder. Bitumen 50/70 was provided with appropriate quality foaming characteristics (expansion ratio, ER, half-life, t1/2) by adding a surface-active agent (SAA) at 0.6 wt % before foaming. Then asphalt concrete (AC) 8 S was designed and produced with the recommended water-foamed binder. Hydrated lime, an additive substantially affecting asphalt concrete mechanical parameters, was used at 0, 15, 30, and 45 wt % as a partial replacement for the limestone filler. The influence of the amount of hydrated lime on the content of voids, indirect tensile stiffness modulus at −10 °C, 0 °C, +10 °C, +20 °C, and +30 °C, and the resistance to permanent deformation was investigated. Statistical analysis of the test results showed the quantity of 30% to be the optimum hydrated lime content. The AC 8 S resistance to permanent deformation was determined at the optimum hydrated lime content. The comprehensive evaluation revealed a synergistic effect between bitumen 50/70, modified before foaming with 0.6 wt % SAA and 30 wt % hydrated lime as the limestone filler replacement, and the half warm mixture AC 8 S, in terms of the standard requirements and durability of the HWMA concrete in pavement applications.

Experimental Study on Mechanical Behaviors of Lime-Stabilized Soils with Small Lime Content

2011 ◽  
Vol 374-377 ◽  
pp. 1823-1826
Author(s):  
Zhong Yu Liu ◽  
Yong Gang Xue ◽  
Xi Jun Wang
Keyword(s):  
Compression Strength ◽  
Compression Modulus ◽  
Curing Time ◽  
Test Results ◽  
Unconfined Compression Strength ◽  
Unconfined Compression ◽  
Mechanical Behaviors ◽  
Lime Content ◽  
Modulus Of Resilience ◽  
Resilience Modulus

In order to investigate the mechanical behaviors of lime-stabilized soils with small lime content, the specimens with 4%~8% lime content and 90%~95% degree of compaction are prepared, and then in use for the unconfined compression strength test, the diametral compression test and the compression resilience modulus test after they have cured in a standard curing room for 7 to 180 days respectively. These test results show that all of the unconfined compression strength, the splitting strength and the compression modulus of resilience increase with the degree of compaction and the curing time. Thereinto, the compression modulus of resilience does rapidly between 28 and 90 curing days, and the unconfined compression strength of the soil with 4% lime content does little after 28 curing days while the compression strengths and the splitting strengths of the other soils do quickly until 90 curing days. In addition, for a given degree of compaction, these strengths of the soils with the less lime content are potentially greater at the early curing time.

scholarly journals MECHANICAL PERFORMANCE OF LIME-CEMENT MORTAR FOR STRAW-BALE CONSTRUCTION

2014 ◽  
Vol 9 (3) ◽  
pp. 100-115
Author(s):  
Colin MacDougall ◽  
Stephen Vardy
Keyword(s):  
Compressive Strength ◽  
Modulus Of Elasticity ◽  
Mechanical Performance ◽  
Failure Strain ◽  
Cement Mortar ◽  
Hydrated Lime ◽  
Empirical Equations ◽  
Curing Time ◽  
Lime Mortars ◽  
Straw Bale

Experimental data describing the mechanical performance of Portland cement- hydrated lime mortars used for straw bale construction is presented. Straw bale construction uses stacked straw bales plastered on each side to form load-bearing elements. Mortars used have slumps of approximately 50 mm, compared to slumps up to 279 mm for conventional masonry mortars. Cylinder and cube tests of a range of typical straw bale mortar mixes were carried out. The mortars had compressive strengths ranging between 0.3 MPa and 13 MPa. Empirical equations describing the relationships between compressive strength and curing time, w/cm ratio, proportions of lime, cement and sand, and modulus of elasticity are presented. The data show that cement-lime mortars for straw bale construction will have a higher modulus of elasticity and lower failure strain than a conventional mortar of equivalent compressive strength. The Modulus of Elasticity is on average 818 times the compressive strength of a straw bale mortar, compared to 100 to 200 times as reported in the literature for conventional mortar. The average failure strain for straw bale mortar is 0.00253 compared to 0.0087 to 0.0270 reported in the literature for conventional mortar.

Fabrication and tribological behavior of novel UHMWPE/vitamin-C/graphene nanoplatelets based hybrid composite for joint replacement

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Omar Hussain ◽  
Shahid Saleem Sheikh ◽  
Babar Ahmad
Keyword(s):  
Composite Materials ◽  
Vitamin C ◽  
Human Serum ◽  
Hybrid Composite ◽  
Wear Behavior ◽  
Tribological Performance ◽  
Graphene Nanoplatelets ◽  
Morphological Examination ◽  
Content Type ◽  
Weight Percentage

Purpose This study aims to fabricate and investigate the tribological performance of ultra-high molecular weight polyethylene (UHMWPE)-based composite materials reinforced with 0.5, 1 and 2 weight percentage of graphene nanoplatelets (GNPs) while keeping the weight percentage of vitamin C constant at 2% for each composite. Design/methodology/approach In this paper, the composites were fabricated using hot pressing, and the dispersion of GNP/vitamin C/UHMWPE hybrid composite was investigated by X-ray diffraction. Experimental trials were performed according to ASTM F732 on a reciprocating sliding tribometer (pin-on-disc) at human body temperature of 37 ± 1 °C, for a load of 52 N, to assess the role of these fillers on the tribological properties of UHMWPE against Ti6Al4V counter body material under dry and lubricating (human serum) environment. Findings In this study, it has been observed that friction and wear behavior of the developed composites improve with increase in weight percentage of GNP, and human serum adheres to the surface of the composite pins upon sliding, resulting in the formation of a film, which results in better wear resistance of the composite pins under human serum lubrication than dry sliding. Scanning electron microscope was used to investigate the worn surface morphological examination of the composite materials. Specific wear rate of 0.76 × 10−7 mm3/Nm was attained for 2 Wt.% GNP-filled composite under human serum lubrication. Practical implications The results indicate the compatibility of the composite material used in this study and suggested the in vitro implant application. Originality/value The presented work includes novel study of synergistic effect of GNP (which acts as a solid lubricant) and vitamin C (added as an antioxidant) on the tribological performance of UHMWPE under dry and human serum lubrication.

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