Stabilization

In this study, the strength development and lechability aspects of metal-contaminated soil treated with ordinary portland cement (OPC) were investigated. The soil was collected from a scrap metal yard within the outskirts of Kuala Lumpur, Malaysia. Metal composition analysis indicated that the predominant metals present in the soil were iron (42,194 mg/kg), aluminium (8874 mg/kg), zinc (690 mg/kg), lead (428 mg/kg), copper (107 mg/kg) and chromium (52 mg/kg). The contaminated soil was treated with OPC using cement-to-dry soil (C/Sd) ratios of 0.5, 1 and 2. The effectiveness of the treatment was evaluated by performing unconfined compressive strength (UCS) as well as crushed and whole block leaching (WBL) tests on the treated soil. The treatment results were compared to the solidified waste acceptance criteria which were compiled based on the regulatory waste disposal limit at a disposal site in the United Kingdom and the maximum concentration of contaminants for toxicity characteristic of solid wastes from United States Environmental Protection Agency. Results indicated that chemical stabilization of metal-contaminated soils using OPC was effective for prevention of metal leaching from both disintegrated samples subsequent to years of weathering (crushed block) and intact samples (whole block) into the environment. © 2005 Elsevier Ltd. All rights reserved.

www.sciencedirect.com/science/article/pii/S0360132305003987

The article discusses the efforts to undertake economic reconstruction in Bosnia following the end of the war. It argues that, despite certain successes such as the rehabilitation of
infrastructure and the privatization of the banking sector, overall progress has been below expectations. The study, accordingly, attempts to analyse the reasons behind the reconstruction
failure by grouping Bosnia’s problems into four different challenges for analytical purposes: the post-Dayton institutional deficiency; overcoming political fragmentation; creating appropriate conditions for economic revival; and graduating from dependency on foreign economic aid. In this respect, it is concluded that the intersection between the economic and political dimensions of post-conflict reconstruction has generated a paradox: while huge amounts of economic assistance have intended to facilitate political reconciliation, the nature of the administrative (political) structure that was established in the post-war period has in turn hindered economic
recovery and the creation of a unified economic space. Moreover, political fragmentation and slow progress in economic reconstruction have been in a mutually constitutive relationship in which the existence of the one has contributed to the sustenance of the other.

Venezuela is currently immersed in a severe economic crisis as a result of years of domestic mismanagement and the recent reversal in oil prices. Against this backdrop this paper attempts to formulate a proposal for stabilization and recovery which includes upfront key policy actions to deal with the drastic foreign exchange constraint. A logical and obvious priority is the redesign of the foreign exchange regime. The recovery of readily available foreign currency liquidity is of paramount importance since it will allow the lift of the exchange control and the implementation stable and competitive real exchange rate (SCRER), but also will provide the required level of liquid foreign exchange that the economy needs to remove shortages across the board and promote the recovery in economic activity. The recovery of domestic output will also require supply-side relief in the form of broad deregulation, institutional changes and a sensible policy to lift price controls. We argue that to maintain a stable and competitive exchange rate, very rapid suppression of inflation and the causal mechanisms built through the years is needed. We propose a plan that comprises three steps: (i) a rapid return to a non-inflationary vector of relative prices through price liberalization (ii) a fiscal and monetary strategy centered on the correct monitoring of the demand for money and (iii) the introduction of unit of indexed value and a new currency to deal with inflationary persistence. The support of monetary and fiscal policy for successful stabilization and recovery efforts is also discussed.

Electric Arc Furnace dusts are considered hazardous waste due to their high heavy metals content (zinc, lead, etc.). The Waelz process is one of the most efficient technologies, in terms of capacity and quality, able to recover nearly the 90% of zinc contained in such EAF dusts. Unfortunately, the resulting slag still has eco-compatibility problems, although its mechanical and chemical properties are suitable for civil engineering applications. Stabilization tests, by quartz addition, were performed on EAF dusts in a laboratory furnace. Temperature, treatment time and cooling rate were varied in order to define the best conditions for regulating the formation of a stable microstructure able to hinder the release of substances. Microstructural characterization was carried-out using SEM and XRD analysis. Leaching tests were performed according to EN 12457-2 standards and water analyses were performed using ICP-OES. The best chemical stability was achieved when dust powders were mixed with 20% of silica and water-cooled.

Venezuela está inmersa en la más severa crisis económica que haya encarado país latinoamericano alguno en la historia moderna, con sombrías perspectivas de recuperación económica en el corto plazo y sin que se vislumbre una voluntad política decisiva para diseñar e implementar un programa económico integral, que atienda
los desequilibrios macroeconómicos, las profundas distorsiones de los precios relativos y la disfuncionalidad de instituciones que mantienen la economía en un estado de caos.

Stabilization of soils is an effective method for improvement of soil properties and the pavement system performance. The poorest soil among all is Black Cotton Soil (BC Soil). In Indore area this BC Soil is spread over almost all parts of District. Rich proportion of montmorillonite is found in BC Soil from mineralogical analysis. High percentage of montomorillonite renders high degree of expansiveness. These property results cracks in soil without any warning. Stabilization of Black Cotton Soil (BC soil) is studied by using Sawdust and Cement. The moisture changes in BC soils, and property and nature of soil has been greatly improved with the addition of Sawdust and Cement. This paper includes the evaluation of soil properties like Optimum moisture content, dry density, and strength parameter (California Bearing ratio value). Different quantities of Sawdust and Cement (% by weight) are added to the BC soil and the experiments conducted on these soil mixes. The result shows that the use of Sawdust and Cement increases the California Bearing Ratio values i.e. the strength of soil to a great extent.

With the development of technology and software, it has become easy to solve difficult problems in every field which use to take a lot of time. The use of software in the field of civil engineering has grown since the last decade. GEO5 is one such software which may be used to solve many geotechnical problems. GEO5 consists of wide range of powerful programs based on analytical method sand the Finite Element Method such as Stability Analysis, Excavation Design, Retaining, Wall Design, Foundation Design, Soil Settlement Analysis, Digital Terrain Model, Geotechnical Finite Element Analysis like analyzing and design of slope, design of retaining walls, settlement analysis, foundation design and much more .It is a very simple and powerful tool for solving geotechnical problems based on traditional analytical methods and Finite Element Methods (FEM).The easy-to-use suite consists of individual programs with a unified and user-friendly interface. Each program is used to analyze a different geotechnical task but all modules communicate with each other to form an integrated suite. In this project modules related to slope stability have been studied in details and then used them for analysis of slope stability. Using GEO5 software the geometry of problems were created in GEO5 and the analysis were carried out considering the stability and economic considerations. Also, the costs of different types of reinforcing methods were determined and compared. It is found that soil nailing is most economical.

Introduction. The overview is given to systematize information on the indicators, affecting the production and stabilization of foams and emulsions, for applying the existing regularities for more complex dispersed (polyphase) systems.
Materials and methods. Analytical studies of the production and stabilization of foams and polyphase dispersed systems published over the past 20 years. The research focuses on the foams, emulsions, foam emulsion systems and the systems, being simultaneously foam, emulsion and suspension.
Results and discussion. Though foams and emulsions have similarities and their production differs in the dispersion rate, determined by the rate of surfactants adsorption. Emulsifying is faster than foaming, therefore, the production of foam emulsions can be sequential only. Coalescence, as a destruction indicator, is typical of foams and emulsions alike, and it is determined by the properties of surfactants. Other indicators are determined by the features of the dispersion medium. The study systematized the factors, ensuring the stability of dispersion systems. The structural mechanical factor is effective in stabilizing foams and emulsions. It is implemented by the usage of proteins only, or solids with partial soaking, or a combination of proteins and low-molecular surfactants or a combination of proteins and polysaccharides. The structural mechanical factor for polyphase systems stabilization, in particular, for foam emulsions, is based on selecting surfactants to regulate rheological properties of interface adsorption layers, the sequence of dispersion phases, which ensures their spatial location in the food product.
Conclusions. The rheological properties of interface adsorption layers, containing proteins, surfactants, polysaccharides and high viscosity of the dispersion medium play the vital part in ensuring the stability of food dispersion systems.

Transportation infrastructure is the key element for the growth of any country and is essential for good physical connectivity in the very small villages, remote areas and hilly areas can be accessed only by roads. “Pradhan Mantri Gram Sadak Yojna” (PMGSY) it was estimated that about 330,000 out of its 825,000 villages and habitations where without any all-weather road access. This Centrally Sponsored Scheme was introduced in 2000 by the Prime Minister of India Shri Atal Bihari Vajpayee. It is under the authority of the Ministry of Rural Development, Government of India and began on 25 December 2000. It is fully funded by the Central Government. For executing the transportation facilities, the quality of a pavement depends on the strength of its soil sub-grade. Soil is very basic and important element in civil engineering field. Usually each structure depends on the type and characteristics of foundation which depends on type of soil. Basically the black cotton soil is rather a difficult one to use in foundation because of its shrinkage and swelling properties.There are many methods to make black cotton soil stable for various constructions. Black cotton soil is comfortable for road work, compared to other types of soil. There are two ways to enhance the quality of subgrade soil -“Replacement of soil” or “Soil stabilization”. Soil stabilization can be done chemically or mechanically. Chemical stabilization is carried out by adding different chemicals in suitable proportion, while Mechanical stabilization is achieved by addition of admixtures which helps to improve the properties of soil. Today, the amount of wastes has increased year by year and the disposal becomes a world faces a serious problem in disposing the large quantity of agricultural waste like Sugarcane Bagasse Ash, rice husk ash and coconut shell etc. This paper presents the effects of Sugarcane Bagasse Ash and Core Fibre on, liquid limit, plastic limit, compaction characteristics and California Bearing Ratio on the black cotton soil. Design and construction of civil engineering structures on and with expansive soils is a challenging task for engineers. The present work is aimed to assess the improvement in the strength and stability characteristics in soft Subgrade soil by using the Sugarcane Bagasse Ash for the stabilization and then Core fibre as reinforcing material. Randomly distributed fibre reinforced soil (RDFRS) technique is used to prepare the reinforced soil samples. In RDFRS technique the mixing of reinforcement in the soil is very easy and no special skill is required. The reinforcement is added by percentage of the weight of the soil sample and by following certain aspect ratio i.e., length/diameter (L/D) ratio. Attempt is made to determine optimum combination of SCBA and core fiber content for maximum gain in strength.

2014 was a hopeful year for the Democratic Republic of Congo (DRC). The M23 movement had been defeated in military operations in which one of the last peacekeeping experiments, the UN Force Intervention Brigade, had played a decisive role. A third UN stabilization plan, the 'islands of stability' was proposed to continue the stabilization of a country considered in a post-conflict phase. However, the number of internally displaced persons (IDPs) has almost tripled in the country since 2007. This article will argue that DRC is still immersed into an old social conflict that existed before the Congo Wars and the roots of which are not being addressed. It will argue that the United Nations Organization Stabilization Mission in the Democratic Republic of the Congo (MONUSCO) and the 'islands of stability' strategy can address some of the secondary causes of the Congo conflict, such as its internationalization, the presence in DRC of foreign armed groups or the 'blood minerals', but cannot address its primary causes: land struggles, an old cycle of violence and the fragmentation of the Congolese society and political elite that is jeopardizing the restoration of the state authority. The huge dimensions of each of these factors make the Congo conflict 'one of the most complex and intricate environments ever faced by a peacekeeping mis-sion', for which MONUSCO's mandate, resources and stabilization strategy do not seem powerful enough. When the UN organized the 2006 elections legitimized a 'spoiler state', the bottleneck of all the reforms needed to stabilize the country. The UN fell thus into a trap and became part of the conflict. Lessons learned should be taken for future UN operations.

Executive Summary

Since the controversial September referendum for Iraqi Kurdish independence, the political stability of the Kurdistan Regional Government (KRG) and its relationship with the Iraqi government has been in crisis mode. The political uncertainty of the KRG has been clouded by the de jure resignation of President Masoud Barzani, an increase in violence and protests, and mounting economic woes. The precarious political balance between Erbil and Baghdad is not only subject to the tensions of internal Kurdish affairs, but also by the complex interests of regional and sub-state actors and the looming Iraqi parliamentary elections in May. Contributors to this response largely agree that actual Kurdish independence is very unlikely in the short-medium term and, moreover, that maintaining the territorial unity of Iraq and Kurdistan is critical to security in the region. However, contributors differ slightly on how to approach facilitating and maintaining stability in Iraq and how to balance competing interests from the KRG, sub-state actors in Iraq, Iran, Turkey, and the international community. Referendum for Independence The independence referendum continues to be both a source and symptom of tension between Erbil and Baghdad. Furthermore, opposition from regional and international actors has resulted in significant setbacks for the KRG. Several experts cite the referendum as the catalyst for the territorial losses, decay of the ruling political class of the KRG, and the punitive measures the KRG has received from the Baghdad, Ankara, and Tehran—all of which makes independence more unlikely (Gulmohamad, Liebl, van

Expansive soil causing problems due to its swelling and shrinkage characteristics. Expansive soils are a worldwide problem that poses several challenges for civil Engineers. Various methods are adapted to improve the engineering characteristics of expansive. Literature is available on adding and mixing the fiber into the soil as this technique has been incorporated since ancient times. Cement created in the ignition of sub bituminous coals shows self-cementing characteristics and can be utilized as a part of an extensive variety of application. In this paper the main focused on increasing the Compressive strength and CBR value of the Black Cotton soil by varying the percentage of Polypropylene fibre in the range of 0.5%, 1.0%, 1.5%, and the Cement is varied as 2%, 4%, 6%, 8% 10%, 12% & 14% by weight of soil mass.

Soil stabilization is a process which improves the engineering properties of soil, such as increasing shear strength, bearing capacity, etc. Expansive soils such as black cotton soil have problem of swelling, shrinkage, & unequal settlement, to improve its properties it is necessary to stabilize the soil by different stabilizers. The evaluation involves the determination of the swelling potential, linear shrinkage, atterberg's limits, & compaction test of expansive soil in its natural state as well as when mixed with varying proportion of margin materials such as waste beverage cans and pet bottles.

This study used eco-friendly materials known as Periwinkle Shell Powder (PSP) in
stabilizing the engineering properties of lateritic soil. Preliminary test was performed
on the un-stabilized lateritic soil for the purposes of identification and classification
(natural moisture content, liquid limits, plastic limits, and plasticity index). The
engineering tests were conducted on the lateritic soil stabilized with additions of (2, 4,
6, 8 and 10 %) PSP and OPC respectively. The result showed that cement gave a
progressive increase in the Maximum Dry Density (MDD) of the lateritic soil from
1875 kg/m3 (2 %) to 2294 kg/m3 (10 %) respectively. This represents 22 % increase
in the MDD from the un-stabilized state. For PSP, the Maximum MDD was attained at
6 % (1974 kg/m3), representing 5.3 % increase in MDD of the soil from the unstabilized
state. For both stabilizing agent, the Optimum Moisture Content (OMC)
increases from 13.65 % to 13.83 % and from 11.72 % to 14.41 % for Cement and
Periwinkle Shell Powder respectively. PSP recorded an increase of 5.6 % of CBR
value compared with OPC that recorded an increase of 34 % CBR value. The study
therefore concluded that Periwinkle Shell Powder (PSP) could be considered as good
stabilizer for clayey or lateritic, and its uses as a stabilizer could also provide a big
relief to the environmental pollution caused by its indiscriminate dumping.

The un peace operations have undergone significant revisions to calibrate mission mandates in tandem with emerging threats to international peace and security, especially non-traditional security (nts) threats that stem from governance challenges. These multidimensional missions essentially perform statebuilding interventions (sbis) through capacity-building programmes. The future of these missions depends on negotiated political settlements that facilitate the creation of accountable institutions and inclusive societies. Scholars debate the future of un peace missions, especially as it relates to stabilization operations. On the one hand, are the " narrowers " who believe that peace operations should remain focused on stabilizing state authorities. On the other hand, are the " broadeners " who favor people-focused stabilization operations. This article argues for a broad approach. Focusing on the role of regional organizations under Chapter viii of the un Charter, it argues that successive failures by the African Union to implement its doctrinal instruments, particularly the Post

Expansive soil causing problems due to its swelling and shrinkage characteristics.
Expansive soils are a worldwide problem that poses several challenges for civil
Engineers. Various methods are adapted to improve the engineering characteristics of
expansive. Literature is available on adding and mixing the fiber into the soil as this
technique has been incorporated since ancient times. Cement created in the ignition
of sub bituminous coals shows self-cementing characteristics and can be utilized as a
part of an extensive variety of application. In this paper the main focused on increasing
the Compressive strength and CBR value of the Black Cotton soil by varying the
percentage of Polypropylene fibre in the range of 0.5%, 1.0%, 1.5%, and the Cement
is varied as 2%, 4%, 6%, 8% 10%, 12% & 14% by weight of soil mass.

Abstract: The utilization of industrial bi-products such as fly ash is of increasing importance as an option for stabilizing contaminated sites due to its pozzolanic nature and also in view of minimising the environmental impact. The experimental programme was carried out in the present study to know the efficacy of fly ash as stabilizing agent at different percentages 20%, 40% and 60% (w/w) on the geotechnical properties of diesel Contaminated Soil (CS). The soil considered in the present work was locally available sandy soil and the common petroleum hydrocarbon diesel engine oil was selected as contaminant. Laboratory studies were conducted on uncontaminated (VS) and soil contaminated to degree of contamination (12% expressed as a dry weight of soil v/w) to compare the geotechnical characteristics before and after contamination. The results show that the consistency limits are affected marginally due to contamination. The compaction characteristics of stabilized soils were observed to be not uniform with increase in fly ash addition. The CBR value of the soil decreased with addition of contaminant and it regain marginally with addition of fly ash.
Keywords: Contaminated soil, Fly ash, Pozzolanic nature, Stabilization.
Title: Stabilization of Diesel Oil Contaminated Soil Using Fly Ash
Author: Dr. Solly George, Aswathy EA, Berlin Sabu, Krishnaprabha NP, Maria George
International Journal of Civil and Structural Engineering Research
ISSN 2348-7607 (Online)

A good transportation system is an essential requirement of any nation. It not only makes the life of the people more convenient but also results in the development of the nation as a whole. Construction and maintenance of roads require proper engineering studies and large capital investment. However, poorly constructed roads not only have lesser durability but also makes riding on the road uncomfortable increasing the operation and maintenance cost of vehicles. Suitable subgrade availability is one of the prime factors while finalizing the road alignment after engineering surveys for road alignment. But sometimes while finalizing the road alignment tradeoff is inevitable between economy and availability of suitable subgrade. Changing the alignment to avoid a weak and unstable subgrade may lead to more construction and/or vehicle operation cost. This is truer especially when a non-suitable subgrade exists for a shorter length along the alignment. In such a situation, the best remedy is to adopt soil stabilization techniques for the non-suitable soil to improve its engineering properties hence make it suitable as the subgrade material. Soil such as clayey soil is an unsuitable subgrade soil mainly because of its large swelling and shrinkage properties. Hence it needs to be stabilized before adopting it as subgrade soil. Present research work deals with the stabilization of clayey soil using coir fiber. Light compaction test and California Bearing Ratio (CBR) test are conducted on the mixture of clayey soil and coir fiber to know the effect of coir fiber in improving the engineering properties of clayey soil. The clayey soil is collected from the Bilasipara region of Dhubri district, Assam state, India. Hence this research work is helpful for infrastructure development activities in the northeastern region of India.

This article assesses progress in and prospects for the US-led campaign in Afghanistan. Drawing on extensive field research, it finds that significant progress has been made at the operational level in four areas: the development of a new population-centric approach to COIN, development of Afghan security forces, growth in Afghan sub-national governance, and military momentum on the ground. However, the situation remains bleak at the strategic level. The article identifies three obstacles to campaign success: corruption in Afghan national government, war-weariness in NATO countries, and insurgent safe havens in Pakistan. Further operational progress will not be able to address this strategic obstacles. Thus there is an operational-strategic disconnect at the heart of the ISAF campaign.

In this paper, a novel non-monotonic Lyapunov-Krasovskii functional approach is proposed to deal with the stability analysis and stabilization problem of linear discrete time-delay systems. This technique is utilized to relax the monotonic requirement of the Lyapunov-Krasovskii theorem. In this regard, the Lyapunov-Krasovskii functional is allowed to increase in a few steps, while being forced to be overall decreasing. As a result, it relays on a larger class of Lyapunov-Krasovskii functionals to provide stability of a state-delay system. To this end, using the non-monotonic Lyapunov-Krasovskii theorem, new sufficient conditions are derived regarding linear matrix inequalities (LMIs) to study the global asymptotic stability of state-delay systems. Moreover, new stabilization conditions are also proposed for time-delay systems in this article. Both simulation and experimental results on a pH neutralizing process are provided to demonstrate the efficacy of the proposed method.

Resumen: Este estudio construye y presenta un ejercicio empírico actualizado sobre los posibles determinantes de la inflación en Venezuela, con el propósito de delinear los componentes de un programa anti-inflacionario. El ejercicio está basado en el llamado " Modelo Triangular " originalmente propuesto por Robert Gordon, cuya especificación (con menores modificaciones) parece recoger bien el proceso inflacionario venezolano. El estudio muestra que la inflación venezolana, durante el extenso régimen de controles (que se da desde el año 2003 y se proyecta hasta nuestros días), está íntimamente ligada a los choques de precios relativos, a los desequilibrios macroeconómicos reales que pueden haberse acumulado como consecuencia de las restricciones de oferta y excesos relativos de demanda, al diferencial cambiario, y al régimen de ajustes e indexación informal que en forma desincronizada le imprimen persistencia a la dinámica inflacionaria. La complejidad de éste proceso descarta cualquier " monismo " como principio de acción contra la inflación y proyecta más bien una estrategia integral. el apoyo prestado en la realización de éste proyecto, sin que con ello tengan responsabilidad alguna en las recomendaciones y conclusiones analíticas del trabajo.

The control problem is discussed for a chaotic system without equilibrium in this paper. On the basis of the linear mathematical model of the two-wheeled self-balancing robot, a novel chaotic system which has no equilibrium is proposed. The basic dynamical properties of this new system are studied via Lyapunov exponents and Poincaré map. To further demonstrate the physical realizability of the presented novel chaotic system, a chaotic circuit is designed. By using fractional-order operators, a controller is designed based on the state-feedback method. According to the Gronwall inequality, Laplace transform and Mittag-Leffler function, a new control scheme is explored for the whole closed-loop system. Under the developed control scheme, the state variables of the closed-loop system are controlled to stabilize them to zero. Finally, the numerical simulation results of the chaotic system with equilibrium and without equilibrium illustrate the effectiveness of the proposed control scheme.

In this paper, we propose a method for effectively tracking moving objects in videos captured using a moving camera in complex scenes. The video sequences may contain highly dynamic backgrounds and illumination changes. Four main steps are involved in the proposed method. First, the video is stabilized using affine transformation. Second, intelligent selection of frames is performed in order to extract only
those frames that have a considerable change in content. This step reduces complexity and computational time. Third, the moving object is tracked using Kalman filter and Gaussian mixture model. Finally object recognition using Bag of features is performed in order to recognize the moving objects.

A paradoxical task of the venom gland of snakes is the synthesis and storage of an instantly available suite of toxins to immobilize prey and the protection of the snake against its own venom components. Furthermore, autolysis of the venom constituents due to the action of venom metalloproteases is an additional problem, particularly among viperid venoms, which are typically rich in lytic enzymatic proteins. To address questions concerning these problems, the structure of the venom gland was investigated using light microscopy, SEM and TEM. The composition of the venom originating from the intact venom apparatus or from the main venom gland alone was analyzed by electrophoresis, and the pH of freshly expressed venom as well as pH optima of several representative enzymes was evaluated. Results from several species of rattlesnakes demonstrated that the venom gland is structurally complex, particularly in its small rostral portion called the accessory gland, which may be a site of activation of venom components. Secreted venom is stable in extremes of temperature and dilution, and several proximate mechanisms, including pH and endogenous inhibitors, exist which inhibit enzymatic activity of the venom during storage within the venom gland but allow for spontaneous activation upon injection into prey. Whereas acid secretion by the parietal cells activates digestive enzymes in the stomach, within the venom gland acidification inhibits venom enzymes. We propose that the mitochondria-rich cells of the main venom gland, which are morphologically and histochemically very similar to the parietal cells of the mammalian gastric pit, play a central role in the stabilization of the venom by secreting acidic compounds into the venom and maintaining the stored venom at pH 5.4. Hence, our results indicate yet another trophic link between the processes of venom production and of digestion, and demonstrate that the venom glands of snakes may represent an excellent model for the study of protein stability and maintenance of toxic proteins.

Examining the causes of the 9/11 attacks and the responses required to diminish the likelihood of future attacks, the Bush administration undertook a comprehensive national security review. Two significant findings emerged. First, contemporary threats facing the United States could not be mitigated by military force alone. Second, it is necessary to stabilize weak or failed states in order to diminish the grievances terrorists and other spoilers use to mobilize support. The 2002 National Security Strategy (NSS) acknowledged this new international environment and declared fragile and conflict states a threat to U.S. security. Consequently, “stabilizing” these countries became a foreign policy goal. The Obama administration’s May 2010 NSS continued this policy. Nevertheless, U.S. responses to unstable environments remain ad hoc and in most cases ineffective. While there are numerous challenges, a key constraint is the lack of practical tools for civilian and military field personnel conducting stability operations. This article examines the features of stability operations; reasons why bureaucratic, doctrinal, and policy changes have not had an effect at the operational and tactical levels; and how the use of USAID’s District Stabilization Framework (DSF) can help practitioners conduct more effective stability operations.

HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci-entific research documents, whether they are pub-lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et a ̀ la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

The black cotton soil is known as expansive type of soil which expands suddenly and starts swelling when it comes in contact with moisture. Due to this property, the strength and other properties of Black cotton soil is very poor. To improve its properties, it is necessary to stabilize the Black cotton soil by using different stabilizers. Expansive type of soil shows unpredictable behaviour with different kind of stabilizers. Soil stabilization is a process to treat a soil to maintain, alter or improve the performance of soil. In this project, the potential of burnt brick dust, crushed powdered glass, cement dust, lime powder are added as stabilizing additives in varying percentages (0%, 10% and 15%). The evaluation involves the determination of Particle size distribution (Determination of grain size by sieve analysis), the atterberg's limits determination (Liquid Limit, plastic Limit and Plasticity Index), specific gravity & Proctor compaction test (Determination of Optimum moisture content and Maximum dry density) of black cotton soil in its natural state (0% addition of stabilizing additives) as well as when mixed with varying proportion of additives such as burnt brick dust, crushed powdered glass, cement dust, lime powder (10% and 15%). The experimental result shows that for various additions of stabilizing additives (10% and 15%) with black cotton soil the Maximum dry density (MDD) of black cotton soil is improving and optimum moisture (OMC) content of black cotton soil is decreasing when compared black cotton soil in its natural state (0% addition of stabilizing additives). The atterberg's limit values are also decreasing for various additions of stabilizing agents (10% and 20%) with black cotton soil when compared black cotton soil in its natural state.

Column generation has proven to be efficient in solving the linear programming relaxation of large scale instances
of the multiple-depot vehicle scheduling problem (MDVSP). However difficulties arise when the instances are highly
degenerate. Recent research has been devoted to accelerate column generation while remaining within the linear
programming framework. This paper presents an efficient approach to solve the linear relaxation of the MDVSP. It
combines column generation, preprocessing variable fixing, and stabilization. The outcome shows the great potential
of such an approach for degenerate instances

A good transportation system is an essential requirement of any nation. It not only makes the life of the people more convenient but also results in the development of the nation as a whole. Construction and maintenance of roads require proper engineering studies and large capital investment. However, poorly constructed roads not only have lesser durability but also makes riding on the road uncomfortable increasing the operation and maintenance cost of vehicles. Suitable subgrade availability is one of the prime factors while finalizing the road alignment after engineering surveys for road alignment. But sometimes while finalizing the road alignment tradeof is inevitable between economy and availability of suitable subgrade. Changing the alignment to avoid a weak and unstable subgrade may lead to more construction and/or vehicle operation cost. This is truer especially when a non-suitable subgrade exists for a shorter length along the alignment. In such a situation, the best remedy is to adopt soil stabilization techniques for the non-suitable soil to improve its engineering properties hence make it suitable as the subgrade material. Soil such as clayey soil is an unsuitable subgrade soil mainly because of its large swelling and shrinkage properties. Hence it needs to be stabilized before adopting it as subgrade soil. Present research work deals with the stabilization of clayey soil using coir fiber. Light compaction test and California Bearing Ratio (CBR) test are conducted on the mixture of clayey soil and coir fiber to know the effect of coir fiber in improving the engineering properties of clayey soil. The clayey soil is collected from the Bilasipara region of Dhubri district, Assam state, India. Hence this research work is helpful for infrastructure development activities in the northeastern region of India.

With rapid growth of population, fast urbanization and more construction of highway, buildings and other structures has resulted in reduction of good quality available land. The mechanical behavior of such nature of soil has to be improved by employing stabilization of Black Cotton Soil (BC soil) is studied by using Lime and Sawdust. Black Cotton soils are highly clayey soils (Montmorillonite clay mineral). The moisture changes in Black Cotton soils, compressibility and plasticity nature can be greatly improved with the addition of Lime and Sawdust. This paper includes the evaluation of soil properties like Optimum moisture content, dry density, and strength parameter (California Bearing ratio value). Different quantities of Lime and Sawdust (% by weight) are added to the BC soil and the experiments conducted on these soil mixes. The result shows that the use of Lime and Sawdust increases the California Bearing Ratio values i.e. the strength of soil to a great extent.