Monday, December 9, 2019
Expansive Soil And Remedies Fly Ash And Lime
Question: Describe the Problems Associated With Expansive Soil And Remedies By Using Fly Ash And Lime. Answer: Introduction The problem of expansive soils has lived with geotechnical engineers since 1930. These kinds of soils are found in almost all the continents of the world. They include soils such as quick clays and collapsible soils. These soils are mostly common in arid regions of the world. However, recent research has shown that the soil has lately stretched to cover even the semi-arid parts (Chen, 2012, p. 56). The expansive soils make it tough for the construction of foundations, more so those of light structures. These soils are characterized by volume changes that result in the swelling or shrinking of the soils. Expansive soils exert upward pressure that is very detrimental to light structures. Massive capital investment is continuously spent across the world to repair the damaged structures (Fredlund, et al., 2012, p. 42). This project work intends to identify all the possible problems that are associated with the expansive soils. In addition, the project proposal further intends to provide a remedy to the problem by the use of fly ash and lime. An extensive list of proposals has in the past been suggested by geotechnical engineers (Sridharan, 2016, p. 23). After taking a keen look at all the suggestions that have been raised, it has been realized that the use of fly ash and lime would be the best solution to the problem. Several precautions have been taken into account in the process of coming up with the suggestion. Issues to do with soil and water pollution have all been taken into consideration in the process of coming up with the suggested remedy. The project proposal would hence provide a benchmark for geotechnical engineers and scholars across the world (Sridharan, 2016, pp. 23-27). Research question, goals, and sub-goals Expansive soil is a problem that has been experienced all across the world. It has caused structural damages very extensively. Regions that experience wet seasons that alternate with dry seasons have been rendered useless by the soils. This has happened to the continuous change of volume of the soils over the seasons. Floors of structures constructed on expansive soils have been prone to cracks that have substantially damaged the structures. Massive crack has also developed across basements of structures on the soils (Ghosh, 2014, p. 87). Walls of building constructed on the soils have also developed arches in the cases where there is no proper reinforcement. Cracks are also a common feature on roads that are built on expansive soils. Such roads are subjected to shrinkage of the soils. Canals, on the other hand, are subjected to erosions (Majeed, 2014). Their soils become soft and are finally swept away. The result is that the canals are washed away too. Swelling of walls have also b een reported in some areas where there are great soils The swellings have been caused by horizontal pressure that has been exerted against the walls, right from within the soils (Iyyunni, 2016, p. 34). Despite all the challenges that are brought about by the expansive soils, other factors should also be taken into account during the construction process. Many engineers have sometimes assumed structural defects to have resulted from expansive soils while thats not the actual cause of distress. It is a matter of the fact that expansive soils are one of the leading causes of cracks in most light structures. Other damages have also been reported in areas where there are expansive soils (Wilson, et al., 2009, p. 78). The damages include leaking and infiltration of water into basements, water pipe breakages during dry seasons, and sticking of doors and even windows. In most cases, the damages take places slowly and over a long period. The result is that buildings and other structures in the neighbourhood are damaged at varying periods. It, therefore, becomes tricky for people to prepare in advance so as to encounter the challenges. Geotechnical engineers have been challenged to seek for a lasting solution to the problems. This project proposal intends to provide a lasting solution to the problems of expansive soils that have lived with us for years (Fang, 2013, p. 37). After a long period of research, we have finally found a solution. The remedy would involve the use of fly ash and lime. The goal of the project proposal is to ensure that people who live in areas with expansive soils would be equally able to put up structures without any problem. It is quite unfair when people in some regions of the world have deprived the freedom that is enjoyed by people in other places. This project proposal, therefore, intends to promote equality among all the people who are living on the surface of the earth (Iyyunni, 2016, p. 97). There have been several attempts that have been undertaken by geospatial engineers to mitigate the effects brought about by expansive soils. The efforts have brought some positive impacts, though. They include landscaping, subsurface drainage and proper preparation of the soil. Landscaping minimized the impact of the problem by ensuring that the amount of water that get access to the surrounding of structures is greatly minimized. Landscaping involves the following of guidelines that outlines how plants that are located close to buildings should be watered. It also prohibits the planting of trees and flowers close to buildings unless they are those that would be watered through drip method. This precaution is taken because the plants tend to absorb a lot of water from the surrounding soils during dry weather. They would hence disrupt the structure of the expansive soils causing them to settle and interfere with structures (Al-Rawas Goosen, 2009, p. 91). Excessive soil moisture is also a major cause of structural damages in expansive soils. Geospatial engineers have hence resorted to the draining of the soils. Proper drainage of the soils that include surface moisture drainage, irrigation and snowmelt have been undertaken to mitigate the effects. Efforts have also been made to drain moisture that has already infiltrated into the ground. Ditches, trenches, and swales have been dug in the affected areas to help in the drainage purposes (John D. Nelson, 2015, p. 42). Underground drainage pipes have also been laid in some regions to collect infiltrated water. The Geotechnical engineers have also advocated for proper preparation of construction sites before any activity in the areas. This has been done by reducing the chances of swelling of the soils wherever they become wet. Despite all these efforts, the effects that are associated with expansive soils have continued to be a menace to people across the world. The efforts made so far have not brought a lasting and permanent solution. This project would improve on one of the suggestions that have been proposed and put into test by geospatial and geotechnical engineers. Feedback from people across the world has shown that ground preparation has been quite effective in the prevention of effects of expansive soils. This would hence provide some motivation and feasibility towards the development of the project. The process would replace the native soil in the areas with a fly ash and limestone mixture (Majeed, 2014, p. 56). The process would provide a kind of chemical treatment to the soils. T he chemistry of the soils would be substantially changed and become considerably less expensive. Theoretical content and Methodology Fly ash and lime contain calcium supplements. Treatment of expansive soils with the use of calcium oxide is a traditional method that has been used over the years. However, the project intends to make the treatment even better. Fly ash would be mixed with limestone and then incorporated into the expansive soils. Water would then be poured upon the mixture to settle the soil particles together. The treatment would bring about an instant impact on the grounds geotechnical properties (Chen, 2012, p. 45). There would be quick drying of the soils as well as its workability. The long term treatment of the soil through the method would promote strength, compressibility and the durability of the expansive soils. The lime-treatment would accomplish the following benefits; There would be increased soil particles allowing spontaneous infiltration of water underground. The process of flocculation-agglomeration would lead to the formation of flock. The Devoid ratio would hence be increased, enlarging the sizes of the particles. The increased devoid ratio provides a reflection of decreased dry density of the soils. Reduction in the plasticity index would be observed. Expansive soils would show a huge reduction when it comes to plasticity index. His would be as a result of the reduced liquid limit as well as increased plastic limit. The addition of lime and fly ash converts the expansive plastic soils into non-plastic. The fixation point of lime would be determined by the amount of lime that would be necessary for the expected values to be achieved. Nevertheless, the fixation point of the lime alone would not be able to generate the recommended strength. The reduced plasticity of the soil would be as a result of the changes like the soil (G. W. Wilson, 2009, p. 29). The application of fly ash and lime would lead to increased durability of the soil. The treated soul would be able to resist and withstand wet and dry cycles that come about as a result of the weather changes in the course of the year. We shall be able to establish the extent of the soils durability by carrying out strength test of the treated soils in varying conditions in the laboratory (Xu Huang, 2012, p. 111). A lime-treated soils experience decreased swelling and changes in volume. Extensive soils are problematic because of their swelling nature and constant changes in volume. Application of fly ash and lime plays a very significant role in ensuring that the plasticity of the soils is heavily reduced. The treated soil would develop higher fatigue strength. The fatigue strength is calculated based on the strength ratio of the soil. Lime contains calcium and is hence adamant. When it is incorporated into the soil, it makes the soil adamant. The strength that would be developed over some period after the treatment of the soil would result in a higher fatigue ratio (G. W. Wilson, 2009, p. 42). A laboratory workshop would be set to confirm the above-listed benefits further. This would verify the workability of the processes in varying extensive soils found in different parts of the world. Experimental set up There would be a laboratory experimental setup as well as field experimental setup. Our geospatial and geotechnical engineers would carry out several tests in the laboratory. The verified results would then be practically carried out in the fields where there are great soils. The locals and the entire members of the public would also be invited to witness the treatment processes. Despite the many advantages that are brought about by application of fly ash and lime, few limitations come along with the treatment of the soils. They include; The treatment process involves undesirable chemical reactions. The process of carbonation of lime and the reaction process between the sulphate salts in the expansive soils and the lime is quite deleterious. Soil distress may also result as a result of the reactions leading to disintegration. This, therefore, possesses a great threat to the entire treatment process which is involving and expensive at the same time (G. W. Wilson, 2009, p. 36). There is also a serious threat that is likely to arise when calcium ions from lime react with aluminium ions in the soil. The good information is that the limitations are not likely to be experienced in all the expansive soils. All the soils do not contain aluminium and sulphate ions. In addition, the limitations can be minimized if precaution is administered during the treatment processes. Our team of highly specialized professionals would carry out all the necessary recommended precautions during the treatment process. This would be done to ensure that the limitations are minimized as much as possible (Majeed, p. 37). Results, Outcome and Relevance Geotechnical engineers have in the past given the green light to the usage of fly ash and lime in controlling the problems that are associated with expansive soils (Chen, 2012, p. 36). By building our project on the result of their feasibility studies, we shall be able to further investigate the process (ProQuest, 2008, p. 51). Before the treatment of the expansive soils by the use of fly ash and lime, a traditional treatment process of the lands would be carried out. The process would be conducted in our laboratories to establish the extent of success when using the traditional method. The outcome of the result would be able to tell the relevance of the method. We would then be able to develop our intended project by building and expanding on the success of the traditional method of soil treatment. Project Planning and Grantt Chart The project planning would start by acquiring the necessary capital necessary to finance the entire the project. A large research laboratory would then be set up. Fly ash and lime would then be purchased. All the other relevant necessities necessary for the treatment of expansive soils would also be acquired. A qualified team of geospatial engineers would then be assembled to undertake the treatment process of sample expansive soils in the laboratory. Several tests would be carried out to determine the extent of success that would be expected once the project is implemented in the field. Once the engineers would be convinced that their objective has been achieved, the treatment process would be carried out in the expansive soils out in fields too. Quality assurance officer from the government ministry of lands would then be invited to monitor the quality of the comprehensive soil treatments. The soil treatment process would then be applied to the field in remote reach regions once the quality assurance officers have approved the entire process. The public as well would be educated on the need of treatment of the soils. In addition, they would be taken through the entire process of treating expansive soils and the limitations that are brought about by the treatment process. It would be important to incorporate the public from the neighbouring surrounding so that they can embrace the entire programs that are carried out within their community. There is a need to ensure that transparency would be observed during the entire process. The community members, the financiers of the project and any other interested persons would only appreciate the project if all the security and transparency measures are observed throughout the entire process. Project schedule Grantt Chart Activity Week1 21/10/2016 Week 2 (10 days) Week 3 Week 4 Week5 Week6 Week 8 Presentation of the project proposal Approval of the project proposal Establishment of the a laboratory Acquisition of fly ash and lime Carrying out of tests Expansive soil treatment in the laboratory Treatment of soils in the field Mobilising the public Educating the public on the need to treat the expansive soils Training the public on the processes involved on the treatment of soil User acceptance testing User training Implementation Conclusion Very many problems have been associated with expansive soils for a much extended period of time. The soils have made it almost impossible for the construction of structures. The structures have in most cases experienced cracks on their floors and walls. The affected people have been very unfortunate given that they have incurred a lot of capital investments in the setting up of the structures that have finally been destroyed by the soils. At the same time, it is very unfortunate to the people living in areas with great soils. The people have had to bear with the soil conditions in the areas whereas other fellow human beings live in areas where they are not faced with problems to do with the soil. The people in other areas of the world where there are no extensive soils have been able set up all kind of structures without any problem. There was hence need to come up with ways of ensuring that people who live on extensive soils are also able to construct structures, just like the people in other parts of the world where there are no great soils. There was hence the need to establish the remedies to the problems that are associated with expansive soils. Some remedies have so far been proposed and put into place by geospatial engineers. However, the proposed solutions have not fully solved the problems. There was hence need to seek for ways and means that would fully eliminate the problems that are associated with extensive soils. Based on the outcome of traditional treatment of the soils, it was discovered that improving the treatment process would make it more effective. This project proposal, therefore, builds on the results achieved from the traditional treatment method of expansive soils. The project uses fly ash and lime to treat and reinforce the soils. The resultant soil from the treatment process would have a good structure. It would allow for the construction of both light and heavy structures without any problem. The treated and reinforced soils would be able to support the structure while at the same time allowing infiltration of water into the ground. The controlled application of fly ash and lime is a remedy that has been tested and approved. It would hence be able to solve all the problems that are associated with expansive soils. References list Al-Rawas, A. A. Goosen, M. F., 2007. Expansive Soils: Recent Advances in Characterization and Treatment. s.l.:Taylor Francis,. Al-Rawas, A. A. Goosen, M. F., 2009. Expansive Soils: Recent Advances in Characterization and Treatment. s.l.:CRC Press,. Al-Rawas, A. A. Goosen, M. . F., 2009. Expansive Soils: Recent Advances in Characterization and Treatment. s.l.:CRC Press. Chen, F. H., 2012. Foundations on Expansive Soils. s.l.:Elsevier. Fang, H.-Y., 2013. Foundation Engineering Handbook. s.l.:Springer Science Business Media. Fredlund, D. G., Rahardjo, H. Fredlund, M. D., 2012. Unsaturated Soil Mechanics in Engineering Practice. s.l.:John Wiley Sons. Ghosh, S. N., 2014. Advances in Cement Technology: Critical Reviews and Case Studies on Manufacturing, Quality Control, Optimization and Use. s.l.:Elsevier,. Iyyunni, C., 2016. Science Direct. Optimum Utilization of Fly Ash for Stabilization of Sub-Grade , pp. 3-7. Majeed, Z. H., n.d. Soil stabilisation using lime. Research gate, p. 2014. Manzanal, D. Sfriso, A. O., 2015. From Fundamentals to Applications in Geotechnics: Proceedings of the 15th Pan-American Conference on Soil Mechanics and Geotechnical Engineering, 15 18 November 2015, Buenos Aires, Argentina. s.l.:IOS Prass. National Research Council (U.S.). Committee on Residential Slabs-on-Ground, 2009. The Design and Construction of Residential Slabs-on-ground: State of the Art. s.l.:National Academies,. Nelson, J. Miller, D. J., 2007. Expansive Soils: Problems and Practice in Foundation and Pavement Engineering. s.l.:John Wiley Sons. Nelson, J. D., Kuo , C. C. Overton, D. D., 2015. Foundation Engineering for Expansive Soils. s.l.:John Wiley Sons. Nelson, J. Miller, D. J., 2007. Expansive Soils: Problems and Practice in Foundation and Pavement Engineering. s.l.:John Wiley Sons. ProQuest, 2008. Moisture Movement Through Expansive Soil and Impact on Performance of Residential Structures. s.l.:ProQuest. Rhoddy, M. K., 2016. Expansive soil problems. Construction deffect assemlies, pp. 2-25. Sridharan, A., 2016. Geotechnical and Geological Engineering. Geotechnical and Geological Engineering, pp. 5-54. Wilson, G. W., Clifton, A. W. Barbour, S. L., 2009. The Emergence of Unsaturated Soil Mechanics. s.l.:NRC Research Press. Xu, J.-M. Huang, P. M., 2012. Molecular Environmental Soil Science at the Interfaces in the Earths Critical Zone. s.l.:Springer Science Business Media,. Yong, R. N., 2001. Geoenvironmental Engineering: Geoenvironmental Impact Management. s.l.:Thomas Telford.
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