-
The Effect Of Partial Replacement Of Conventional Fine Aggregate (sand) With Lateritic Soil In The Production Of Sandcrete Bricks
CHAPTER TWO -- [Total Page(s) 9]
Page 1 of 9
-
-
-
CHAPTER TWO
2.0 Literature Review
Laterite is often used to describe the clinkered siliconized clay material. According to Amu et.al. (2011), it could be described as materials with no reasonable constants properties while Villain Cocinaet et.al. (2003), described it as a red friable clay surface, a very hard homogenous vesicular massive clinker-like material with a framework of red hydrated ferric oxides of vesicular infill of soft aluminum oxides of yellowish color. Villain Cocinaet et.al. (2003), opined that mechanical stability is an important factor that should be considered in the use of lateritic materials. On the other hand, mechanical instability may manifest in form of remoulding and recasting and breakdown of cementation and structure. The mechanical instability can affect engineering properties of laterite such as particle size, Atterberg’s Limits, Moisture content, Grain size, among others which in turn affect the strength of laterized product. Middendorf et.al. (2003) and Day, (2003).
These properties can however, be improved through stabilization in order to improve the characteristics and strength. O’Flaherty (2002), and Amu et.al. (2011) described soil stabilization as any treatment applied to a soil to improve its strength. Different methods have been used in laterite stabilization. In recent years, mechanical and chemical stabilization being the two most popular methods in operation all over the world. Laterite stabilization using mechanical approach involves blending of different grades of soils to obtain a desired standard. Chemical stabilization on the other hand, is the use of silicon friendly material in blending of natural clay with chemical agents such as Pozzolana soda ash, fly ash cement among others.
The term laterite is used to describe a ferruginous, vesicular, unstratified and porous material with yellow ochre caused by its high iron content, occurring abundantly in Malabar, India (Osunade, 2002).
It was locally used in making bricks for buildings, and hence the name “Laterite†was derived from the Latin word “Later†meaning “Brickâ€.
Although laterite is a material that has been used in the building construction industry in Nigeria for a very long time, especially in the rural areas, there is a paucity of data describing the behavior of this material. There is therefore the need to improve indigenous technology on the practical usefulness of lateritic soils in the construction industry. A lot of research activities are now being carried out on lateritic soils. Previous work on laterized concrete appear to have been a study in which the strength properties of normal concrete were compared with those of laterized concrete(Adepegba, (1975). The conclusion of that study was that concrete in which laterite fines are used instead of sand can be employed as structural material in place of normal concrete.
According to Balogun and Adepegba (1982), when sand is mixed with laterite fines, the most suitable mix for structural application is 1:1.5:3 (cement, sand plus laterite fine gravel) with a water cement ratio of 0.65, provided that the laterite content is kept below fifty percent (50%).
It has also been established by Lasisi and Osunade (1994) that the finer the grain size of lateritic soils, the higher the compressive strength of the unstabilized cubes made from such soils.
In a study on the effect of mix proportion and reinforcement size on the anchorage bond stress of laterized concrete, Osunade and Babalola (1991) established that both mix proportion and the size of reinforcement have significant effect on the anchorage bond stress of laterized concrete specimens. The richer the mix proportion, in terms of cement, the higher the anchorage bond stress of laterized concrete (Osunade and Babalola, 1991). Also the anchorage and stress between plain round steel reinforcement and laterized concrete increases with increase in the size of reinforcement used.
The study by Osunade (1994) found out that increase in shear and tensile strength of laterized concrete were obtained as grain size range and curing ages increased. Also, greater values of shear and tensile strengths were obtained for rectangular specimens than those obtained for cylinders. Stabilized and unstabilized lateritic soils have been reinforced with different reinforcements (e.g. rope, grass, saw dust etc) and results have generally shown that performance characteristics of lateritic soils can greatly be improved using such reinforcement.
2.1 Bricks Work
Are the dominant units for modern wall construction in Nigeria and indeed West Africa. They are of many types depending on the constituent materials. The constituents also determine the structural characteristics of the bricks. The major types are sandcrete bricks (water, cement and river sand), soilcrete bricks (water, cement and laterite), sandcrete bricks (burnt clay and additives) and mud blocks. The bricks come in various sizes and usually sand-cement mortar or lime. Other various types of brick, the most common in Nigeria is sandcrete brick. Efforts have been made to encourage the use of the other types of bricks especially soilcrete bricks. To this regards, a lot of research work has been carried out on the use of soilcrete bricks in building projects in Nigeria. However, in spite of the reported comparative saving in cost and the formulation of suitable mixes to meet the requirements as walling units (Agbede and Manasseh, 2008, Adam, 2001, ,Boeck et al, 2000. The use of soilcrete in modern building construction in Nigeria, to say the least, is not encouraging. The same goes for bricks. The low usage of soilcrete brick and block in Nigeria can be attributed to the long time spent in production of the soilcrete bricks and the blocks as compared to the easy production of sandcrete bricks.
CHAPTER TWO -- [Total Page(s) 9]
Page 1 of 9
-
-
ABSRACT - [ Total Page(s): 1 ]ABSTRACT WILL BE HERE SOON ... Continue reading---
CHAPTER ONE - [ Total Page(s): 2 ]CHAPTER ONE1.0 Introduction Lateritic soils are formed in hot, wet tropical regions with an annual rainfall between 750 to 300mm, (usually in areas with a significant dry season) on a variety of different types of rock with high iron content. The location on the earth, that characterize these conditions fall between latitude 35oS and 35oN (Person, 1970).Laterisation is the removal of silicon through hydrolysis and oxidation that result in the formation of laterite and lateritic soil ... Continue reading---
CHAPTER THREE - [ Total Page(s): 7 ]ProcedureAbout 200g of soil sample was passed thoroughly with distilled water to form a uniform paste. A portion of the paste was placed in a brass trough bar (linear shrinkage trough device). The surface of sample was leveled and smoothened off to the brass of the trough bar and the trough was then placed in an oven for 24 hours at temperature of about 105°C. The initial length of the trough bar filled with the soil sample was taken. After 24 hours, the trough bar was brought out of the oven ... Continue reading---
CHAPTER FOUR - [ Total Page(s): 15 ]PERCENTAGE OF STABILIZER ... Continue reading---
CHAPTER FIVE - [ Total Page(s): 1 ]CHAPTER FIVE5.0 CONCLUSIONS, REFERENCE AND RECOMMENDATION. 5.1 Conclusion. Tests
have been conducted to evaluate the suitability of lateritic soils
along Asa dam area Ilorin kwara state and its effect on the strength of
sandcrete bricks when used to replace the conventional fine aggregate,
the following conclusions can be drawn from the analysis of the results:
I. The use of lateritic fine as a partial replacement has a significant influence on the engineering pro ... Continue reading---
REFRENCES - [ Total Page(s): 3 ]REFERENCESAdam, E. A. (2001): Compressed Stabilised earth block manufactured in sudan, A. Publication for UNESCO (online) Available from http://unesdoc.unesco.org.Adepegba, D.A. (1975). “Comparative Study of Normal Concrete which contains Laterite Fines instead of Sand†Building Science; 10:135-41.Agbede, I.O. and Manasseh, V. (2008): use of cement sand admixture in lateritic brick production for low cost housing Leonardo electric Journal of practices and technology, 12, pp163-174.Ak ... Continue reading---
