Project Background

Discuss About The Microbial Induced Calcium Carbon Precipitation.

Bearing Capacity is the capability of sand to carry the pressure set on the sand from all civil engineering structures without necessarily going through a shear failure with complementarily vast settlements (Prasad, 2013).Putting on a bearing pressure which is harmless with regards to failure, does not guarantee that the settlement of the foundation will be within acceptable limits. Hence, settlement analysis ought to be done since most structures are subtle to too much settlement.

 The commonly acknowledged technique of bearing capacity analysis is that, one should assume that all the sand beneath the foundation alongside a critical plane of failure is on the threshold of failure and to determine the bearing pressure applied by the foundation which necessarily causes this condition of failure. Thus, it is the final bearing capacity of sand (Lee et al. 2013).

Various methods will be used to gather data related to the topic of research such as; A sand exploration and site investigation program or should be conducted in order to obtain the required for analysis of the bearing capacity of sand. An exploration into the existing literature will be made so as to enable an in-depth comprehension of the current street light controls systems. The literature will be analyzed to come up with ways Improvement of bearing capacity of sandy soil by grouting.  

This paper contains the following sections; the introductions which explain the background of the project, the aims, and objects of the project, the scope and boundaries of the project and the significance of the project. The literature review section contains the information about the research which has been conducted by other scholars regarding the design and implementation of the automatic street lights. The methodology section discusses the various methods that were used to collect the data. The discussion section which discusses the various data and information obtained during the research. The conclusion section summaries the entire paper. Finally, the bibliography section lists the various masteries which were reviewed during the research.

The improvement of the bearing capacity of sand can be achieved by various techniques such as assumption piles, compaction with explosives, grouting, replacement, and excavation (Rollins and Brown 2011). The selection of the most appropriate techniques depends on a variety of factors such as, the required degree of compaction, conditions of the soil, specific considerations which are available and the type of the structure to be supported.

Aims and Objectives of the Project

Sandy soils refer to the type of soil which have particles which are large than 2mm in diameter.it has good drainage of water, and it generally has low ability to hold nutrients. The sandy soil is known to have minimal ability to hold moisture (Basso, 2013). It consists of minerals and rock particles which are very small. Hence the texture of the sandy soil is gritty and is developed by the weathering and disintegration of rocks such as granite, limestone, shale, and quartz. The sandy soil is easier to in the situations where it is rich in organic materials, but at the same time, it permits drainage than required. This results in dehydration and over drainage of the plants (Ulyett et al. 2014).

Grouting is a process whereby stabilizes either in the forms of suspensions or solutions which are injected into the subsurface soil (Van Paasse, 2011). When the soil is rubbed, it feels rough. This is due lack of nutrients in the sand and due to the sharp edges.

The aims and objectives of the study were as follows;

1. To establish the nature of the particles of sandy soil
2. To find out the degree of the sand soil compatibility
3. To conduct the improvement of sand soil through grouting
4. To conduct some laboratory test on sand soil such as compaction test CBR test.

The findings from this project will be of great significance to various parties who are involved in the construction of engineering structures. They will be able to understand how to improve the bearing capacity of sand to Improve stability and safety of the engineering structures.

The construction of engineering structures on the ground which is considered to be weak requires the soil to be improved in order to facilitate stability and safety of the surrounding structures. This research will focus on the improvement and quality of bearing capacity of sand soil by grouting. 

The history and development of compaction grouting have been established by many distinguished scholars, researchers, and contractors. Many reports have been published regarding directly with the issues around the improvement of bearing capacity of sand. The compaction grout technique which is referred to as compaction grouting (Mortensen et al. 2011). This technique has some unique features which permit other distinct benefits over other remedial management of geotechnical construction.

1. Economy

In most cases, compaction grouting is the only feasible solution to the problems encountered in foundation settlement, other than demolishing the entire structure and re-building by applying deep foundation method which is very expensive (Jaeger Plantinga,and Grout 2012).

1. Minimal disturbance

In the process of grouting operation, the structure may remain in service and occupied.

• Minimal risk

Compaction grouting provides minimal risk of catastrophic structural failure while reveling structure (Yongmao and Junhui 2010).

Significance of the Project

The low bearing capacity of sand causes excessive settlement and shear failure. In addition, the water table and the limited depth of the sandy layer limit the depth of the foundation thereby reducing the bearing capacity further. Based on that an experimental investigation which was made on the sandy and grouted soil it was concluded that grouted soil has the good plastic limit, liquid limit, bearing and compaction ratio are high when they are compared to the ordinary sandy soil. (Gopalsamy et al. 2017)

The construction of various engineering structures along the coastal areas regularly calls for deep foundations due to the poor engineering properties and other related challenges arising from the weak sand at shallow depth. The low bearing capacity of the foundation because of excessive settlement and shear failure. The shear strength of sand soil steadily improves with the increase in the amount of cement content and also with the increase of the curing period. The rate at which shear strength increase is high at higher percentages as compared to the lower levels of cement content. The response of sand to the stress-strain displays a linear relationship before the peak value for cement (Santhosh 2016).

Permeation grouting is considered to be a simple technique of ground improvisation method which assists in stabilizing the loose soil stratum. Grouting is a process of ensuring that the pores present in a given type of soil are filled by use of cement slurry in order to enhance the engineering properties. The shear strength in the dense and loose state of sandy is investigated by use of plate load test on the soil which is grouted by establishing the relationship between the displacement and the load on the grouted soil sample. The results of a series of load tests which are carried out on the grouted sand gave a conclusion that a comparison in the strength behavior between loose and medium dense sand when they are grouted with the water-cement ratios displays that the grouted medium dense to loose sand is much higher and it shows a brittle type failure to load.

Research methodology is described as a rigorous methodology that assures the analyst to collect proper data or to clinch examination concerning to his/her subject by using various research strategies. The goal of the proposed research is to improve bearing capacity of sandy soil by grouting. The goals were established in order to contribute to realizing the key purpose of the study .Due to that, it was important to have an outline of Improvement of bearing capacity of sandy soil by grouting. The following methods will be to gather data about Improvement of bearing capacity of sandy soil by grouting;

Scope and Boundaries of the Project

A sand exploration and site investigation program or should be conducted in order to obtain the required for analysis of the bearing capacity of sand. Approximation of legal and ultimate bearing capacity of sand by use of analytical equation model the shear failure of the given structure along the slip surfaces in the methods and soil for analyzing on-site test (Fleming and Randolph 2014).

An exploration into the existing literature will be made so as to enable an in-depth comprehension of the current street light controls systems. The literature will be analyzed to come up with ways Improvement of bearing capacity of sandy soil by grouting. Various books and other publications that contain data regarding the Improvement of bearing capacity of sandy soil by grouting

By conducting the literature review, the author could pass the knowledge about the Improvement of bearing capacity of sandy soil by grouting, and it would include the main features of a topic. This research approach is of great importance in achieving the objectives and aims of the research. This research approach is also very helpful in attaining all the objectives and aims of the research such as to have a summary Improvement of bearing capacity of sandy soil by grouting

• The secondary data exists, unlike the primary sources which one has to gather the data by his/her own.
• The secondary sources usually contain a very large amount of information such as statistical bases, expert’s articles, and government reports
• The secondary sources are much cheaper as compared to the primary sources, or some of the secondary sources are free in that one can browse online and acquire the required data.
• Most of the secondary sources are easy to access. Most of the secondary sources of data regarding the design of the automatic street lights design are easily accessible.
• Clarification of the research questions. The secondary sources may be of great help in clarifying the research questions. They will be used to help clarify the research question before the primary sources are implemented. The review will be of great help before the primary sources are conducted.
• The secondary sources can show the possible challenges to be encountered during the primary research. By reviewing the various secondary sources, it is possible to identify the challenges which are likely to be encountered.

There are drawbacks which are associated with the use of secondary sources in carrying out the research some of them include:

• The quality of data obtained might be compromising in that the originator of the data might have been largely self-governed or controlled by the market (Cheng and Phillips 2014).
• Some of the data obtained from the secondary sources might have been outdated. Thus affecting the overall outcome of the research.
• The data obtained from the secondary sources might be incomplete in that the research which was documented in the secondary sources might have been done to the expected standards.

The data obtained might not be specific to the researcher’s needs. Some of the information contained in the secondary sources might not be directly related to the topic of research.

The emphasis of this project is Improvement of bearing capacity of sandy soil by grouting. Below is the set up for the experiment. The primary tests for the valuation of enhancement in load holding capacity via densification will be carried out by putting the sand at the wanted densities in minor tanks of size 30x30x30. The density at weakest state was13.1 kN/m3 and at most dense state, I was 16.2 kN/m3. Enhancement in sheer power of the soil can be found by enhancing both the c and Ø values. Grouting which modifies the pore structure and improves the interlocking and bonding between particles can give substantial development inc as well as Ø values. To position the grout inside the pores of the granular medium, two approaches ware approved. In the first approach, the grout was placed within the pores through hand mixing in order to obtain a constant grouted bed.

Materials used; Sand soil, tap water, and Sodium Silicate

Conclusion

In conclusion, Sandy soils refer to the type of soil which have particles which are large than 2mm in diameter.it has good drainage of water and it generally has low ability to hold nutrients. The sandy soil is known to have minimal ability to hold moisture. It consists of minerals and rock particles which are very small.

The construction of engineering structures on the ground which is considered to be weak requires the soil to be improved in order to facilitate stability and safety of the surrounding structures. Therefore there is a need for improvement and quality of bearing capacity of sand soil by grouting in order to increase stability and safety of the engineering structures constructed on sandy soil (Bell, 2013).

References

Basso, A.S., Miguez, F.E., Laird, D.A., Horton, R. and Westgate, M., 2013. Assessing the potential of biochar for increasing water?holding capacity of sandy soils. Gcb Bioenergy, 5(2), pp.132-143.

Bell, F.G. ed., 2013. Methods of management of unstable ground. Elsevier

Cheng, H.G. and Phillips, M.R., 2014. Secondary analysis of existing data: opportunities and implementation. Shanghai Archives of Psychiatry, 26(6), p.371

Fleming, K., and Randolph, M. 2014. Piling engineering. CRC press.

Lee, K.K., Cassidy, M.J. and Randolph, M.F., 2013. Bearing capacity on sand overlying clay soils: experimental and finite-element investigation of potential punch-through  failure. Géotechnique, 63(15), p.1271.

Jaeger, W.K., Plantinga, A.J. and Grout, C., 2012. How has Oregon’s land use planning system affected property values?. Land Use Policy, 29(1), pp.62-72.

Prasad, S.K., 2013. Bearing capacity of the soil. SJ College of Engineering, Mysore.

Ulyett, J., Sakrabani, R., Kibblewhite, M. and Hann, M., 2014. Impact of biochar addition on water retention, nitrification and carbon dioxide evolution from two sandy loam soils. European Journal of Soil Science, 65(1), pp.96-104.

Mortensen, B.M., Haber, M.J., DeJong, J.T., Caslake, L.F. and Nelson, D.C., 2011. Effects of environmental factors on microbial induced calcium carbonate precipitation. Journal of applied microbiology, 111(2), pp.338-349.

Rollins, K.M. and Brown, D.A., 2011. Design guidelines for increasing the lateral resistance of highway-bridge pile foundations by improving weak soils (Vol. 697). Transportation Research Board.

Van Paassen, L.A., 2011. Bio-mediated ground improvement: from laboratory experiment to pilot applications. In Geo-Frontiers 2011: Advances in Geotechnical Engineering (pp. 4099-4108).

Yongmao, Y. and Junhui, P., 2010. Construction Technology of Double Grouting for Bored Piles in Some Project [J]. Construction psychology, 1, p.027.