Analysis of the Problems and Prospects in the Use of Local Building Materials: Review of Literature

One of the strong considerations for the use of Local Building Material (LBMs) in housing delivery is that it could reduce cost and enhance foreign exchange earnings.  This paper examines the type of LBMs, problems envisaged in the use of LBMs, its prospects among other issues. This paper is essentially a review of literature from which inferences are drawn. Recommendations towards the use and acceptability of the LBMs include; (i) that various government agencies should engage in the use of LBMs rather than mere campaigning to developers (ii) that every state should establish cottage building industries to improve the supply, and that more researches should be engaged on for more discovery of LBMs

Managing the Unwanted Materials: The Agony of Solid Waste

Abstrac

Optimizing the rheological properties of silica nano-modified bentonite mud using overlaid contour plot and estimation of maximum or upper shear stress limit.

An optimization based statistical (response surface) approach was used to evaluate the rheological properties of bentonite mud treated with silica nanoparticles. The overlaid contour plot established the feasible region for the various factor settings from multiple regression equations. The steepest method was used to further determine the optimal factor settings for minimum rheological properties and this was established at 6.3 wt.% bentonite content and 0.94 wt.% silica nanoparticles. The rheological properties of the bentonite mud containing and without silica nanoparticles was evaluated using a Hyperbolic (new) model and related with other oil industry based models: Herschel Bulkley, Sisko, Casson. The hyperbolic rheological model estimated the rheological behaviour of the nano-modified mud satisfactorily while also predicting a shear stress limit for the nano-modified mud. The maximum shear stress limit values for 6.3, 13 and 15 wt.% mud were 14.59, 61.74 and 107.4 Pa respectively. Upper shear stress values obtained from a 1.5 wt.% silica nanoparticle modified 6.3, 13 and 15 wt.% bentonite mud were 22.27, 72.62 and 171.3 Pa respectively, which represents an increment of 34.5 to 37.4% in the upper limit of shear stress. The effect of silica nanoparticles on the upper shear stress limit was quantified using a response surface design