LEGEND OF CIVIL

Soil liquefaction can be defined as the phenomenon by which the strength of the soil is lost either due to dynamic or static loading. Most of the earthquake forces are the major causes of soil liquefaction. The vibrations of earthquake shockwaves in water-saturated soils trigger the phenomenon. |                                                        saturate soil                Liquefaction occurs in saturated soils, that is, soils in which the space between individual particles is completely filled with water. This water exerts pressure on the soil particles that influence how tightly the particles themselves are pressed together. Prior to an earthquake, the water pressure is relatively low. However, earthquake shaking can cause the water pressure to increase to the point where the soil particle...

    The essential ingredients of paints are: Base Vehicles Pigment Drier/ accelerator Thinner Base: It is a principal constituent of paint. It also possesses the binding properties of the finely divided material. It is opaque (untransparent) in nature. Commonly used bases for paints are white lead, red lead, zinc oxide, iron oxide, titanium white, aluminum powder and lithophone. A lead paint is suitable for painting of iron and steel works, as it sticks to them well. However it is affected by atmosphere action and hence should not be used as final coat. While zinc forms good base but is costly. Lithophone, which is a mixture of zinc sulphate and barytes, is cheap. It gives good appearance but is affected by day light. Hence it is used for interior works only. Vehicles : It helps to mix the various ingredient use in paint. The vehicles are the liquid substances which hold the ingredients of a paint in liquid suspension and allow them to be applie...

1) OVER-BURNING OF BRICKS During the production of bricks, we have to burnt bricks to achieve sufficient hardness after moulding clay into a required shape. During heating, if the brick overburnt , then soft molten mass is produced and the brick looses its required shape. Bricks should be burned at temperatures at which incipient complete and viscous vitrification occur. However, if the bricks are over burnt, a soft molten mass is produced and the bricks loose their shape. Such bricks are not used for construction works. 2) UNDER BURNING OF BRICKS When bricks are not burnt to cause complete vitrification, the clay is not softened because of insufficient heat and the pores are not closed. This results in higher degree of water absorption and less compressive strength. Such bricks are not recommended for construction works. 3) BLOATING This defect observed as spongy swollen mass over the surface of burned bricks. This is caused due to the presenc...