EFFICACY OF SODIUM CARBONATE AND CALCIUM CARBONATE IN STABILIZING A BLACK COTTON SOIL
The problem of damage to structures in expansive soils is world wide. These soils are very often referred as black cotton soils. The properties of black cotton soil may be improved to make the soil suitable for construction purposes. There are several techniques to improve the soil properties like sand cushions, CNS layer techniques, sand columns, stone columns, vibration techniques and by adding chemicals etc. Among these, chemical stabilizing is more expensive than other types of stabilization methods. But the main advantage of it is that setting time and curing time can be controlled. The efficacy of sodium carbonate and calcium carbonate is stabilizing a black cotton soil is presented in this paper. The efficacy of calcium carbonate is much better than sodium carbonate from strength and stability point of view.
Studies on Strength Characteristics of Soil Mixed with Guar Gum
Natural biopolymers discussed as environmentally friendly and sustainable grouting chemicals. This paper presents guidelines for selecting potentially useful biopolymers for strengthening cohesion soil. Soil is a universally available natural material derived mostly from rocks and rocky minerals. As soil is a product of nature, possess an inherently variable and complex character. The load bearing capacity is the most important soil property, which governs the design of pavement Guar gum was identified for the study over a range of concentration (0.5%, 1.0%, 1.5%, 2.0%, 2.5%, and 3.0%). Experimental results of Expansive soil treated with various percentages of Guar gum gel for various water content and cured samples of 0, 3,7days. Strengthening effect of Guar gum was shown to have greatest effect on expansive soil with curing periods. Depending on biopolymer concentration, the unconfined compressive strength of expansive soil treated with Agar gum biopolymer. Unconfined compressive strength tests over a range of confining pressures also indicated that the biopolymers effectively increased the expansive soil intercept and CBR values of the treated expansive soil.
Comparison of a Radiometric Procedure with Conventional Methods for Identification of Neisseria
A radiometric procedure was compared with the conventional cystine tryptic agar (CTA) sugar fermentation method for identification of Neisseria species. Four different ATCC cultures of Neisseria were identified by both procedures with identical results. The only difference noted was that the radiometric procedure required 3 h for completion, whereas the conventional CTA sugar method required overnight incubation. The radiometric procedure was also compared with the fluorescent antibody (FA) and CTA methods for identification of Neisseria gonorrhoeae. The organisms examined were gram-negative, oxidase-positive diplococci isolated from 49 clinical specimens sent to the laboratory for bacteriological analysis. Results obtained by both CTA and FA procedures were comparable. However, the radioisotope method appeared to be superior to the other two methods in that only one isolate identified as positive by both the CTA and FA methods was not identified radiometrically, whereas four isolates positive by the radiometric method were not identified by the other two procedures. Thus, a total of seven more positive identifications were made radiometrically than by either of the two other methods. All positive identifications were confirmed by a reference laboratory. These results indicate that the radiometric procedure is more rapid and reliable as compared with both the CTA and direct FA methods and, thus, may serve as a valuable addition to the methodology available for diagnostic microbiology.