Scientific World, Vol. 11, No. 11, July 2013, page 43-47 DOI: http://dx.doi.org/10.3126/sw.v11i11.8551

No abstract

Physical and mechanical properties of seven ancient clay brick samples of Kathmandu valley consisting of quartz, feldspars, spinel, margarite, muscovite type of mica mineral and hematite were studied using ASTM standards. All the brick samples used in this study have the water absorption, apparent porosity and bulk density in the range of 10-28 percent, 17-33 percent and 1.2-1.8 g/cm3, respectively, while the compressive strength of all the brick samples is found to be in the range of 5-23 MPa. The bulk density of the tile samples is found to be increased with decreasing the water absorption and apparent porosity. The compressive strength of all the clay brick samples can be correlated with their physical properties. Consequently, durability of the ancient bricks is directly influenced by their physical properties of water absorption, apparent porosity and bulk density.

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The passivation behavior of carbon steel rods of Nepal is studied in 1 M HCl, 0.5 M NaCl and 1 M NaOH solutions at 25°C, open

No abstract

This research work is carried out to identify the corrosive nature of soils towards the buried-galvanized steel and cast iron pipelines buried in Sanothimi areas of Madhyapur Thimi municipality, Bhaktapur based on different soil parameters such as organic content, moisture content, pH, resistivity, oxidation-reduction potential, chloride and sulfate ions. The soil parameters of the collected soil samples from the study areas were analyzed using standard ASTM methods. Concentrations of these soil parameters measured in this study were found as: organic content (0.9- 7.9%), moisture content (8.0-36.7%), pH (6.8-7.7), resistivity (3900-16700 ohm.cm), oxidation-reduction potential (337-461 mV vs SHE), chloride (25-71 ppm) and sulfate (35-464 ppm) contents. These soil parameters gave an indication of “mildly corrosive” to “less corrosive” nature of soils on the galvanized steels and cast iron pipelines buried in the study areas. Based on the findings of the present studies, it can be advised to the related authorities or local people that simple modification of the soils by using cheapest non-conducting materials like gravel or sand around the buried water supply pipelines before undergrounding them in the study areas is very beneficial from the corrosion point of view to increase their life time. DOI: http://dx.doi.org/10.3126/bibechana.v11i0.10387 BIBECHANA 11(1) (2014) 94-102

Present research work was focused to investigate the firing temperature effects on mineralogical phase composition of nine clay bricks collected from the brick factory of Kathmandu valley using X-ray diffraction (XRD) patterns and Fourier transform infrared (FTIR) spectra analyses. Main mineralogical phases of quartz, feldspars, spinel, mullite and hematite in the brick specimens fired at different firing temperatures including muscovite type of mica mineral in the sun-dried brick specimen are identified from XRD and FTIR analyses. Disappearance of the muscovite type of mica clay mineral with feldspars enhanced to form alumina rich spinel phase at firing 900° to 1000° C, and finally the primary mullite phase in the fired clay brick samples is clearly observed at 1100° C firing temperature.BIBECHANA 16 (2019) 122-130