Imagine the challenges of building a tunnel in an urban setting – for example, to construct a metro system in a big city such as London, New York, or Montreal. Civil engineers design, develop and build different types of structures. The increasing need for rapid and effective ways to move people and goods has led…
Weight Volume Relationship Of Soil The physical properties of a soil give insight as to the identification of the soil and the determination of its characteristics and load response. These properties can be determined by performing a laboratory analysis on undisturbed soil samples obtained during the test boring process. The laboratory analysis should be performed in accordance with the…
Weathering Of Rock Mass ‘Weathering is the process of alteration and breakdown of rock and soil materials at and near the Earth’s surface by chemical decomposition and physical disintegration’ Of particular note in this definition is that weathering is described as a process. It is not a method for describing the engineering properties of a rock mass. As…
Fast growing trees close to buildings can cause unequal settlement when active tree roots dry out the soil causing differential soil shrinkage. Shrinking clays affect the bearing capacity and lead to movement in the building, especially in shallow foundations. Tree roots can extend over a considerable distance and can extract moisture from as deep as 6…
Active research is being conducted by scientists to obtain details about the movement of tectonic plates. These movements are responsible for geological events including earthquakes, volcanoes, formation of mountains, sea floor spreading, and island arcs. Most action takes place at plate boundaries. The Modern Theory of Plate Tectonics The modern theory of plate tectonics (not…
The following tests are conducted on the prepared mortars to ensure their quality: 1. Crushing Test 2. Tensile Strength Test 3. Adhesive Test. 1. Crushing Test: This test is carried out on a brick work with the mortar. This brick work is crushed in a compression testing machine and the load is noted down. Then the…
Clay lumps are collected and are wetted with water and allowed to mature for 1 or 2 days. It is kneeded well until it attains required consistancy. Sometimes fibrous materials like gobber is added in the mix. It prevents cracks in the plaster. If plaster is to be used for outer walls, it is sprayed or painted with Bitumen. It…
Fat lime and hydraulic limes are used for making lime mortar. If fat lime is used sand mixed is normally 2 to 3 times its volume. If hydraulic lime is used sand mixed is only 2 times the volume of lime. Lime is prepared by pounding, if quantity required is small or by grinding, if the required…
For preparing mortar, first a mixture of cement and sand is made thoroughly mixing them in dry condition.Water is gradually added and mixed with shovels. Curing: Cement gains the strength gradually with hydration. Hence it is necessary to see that mortar is wet till hydration has taken place. The process to ensure sufficient moisture for hydration after…
Sand is a natural product which is obtained as river sand, nalla sand and pit sand. However sea sand should not be used for the following reasons: 1. It contains salt and hence structure will remain damp. The mortar is affected by efflorescence and blisters appear. 2. It contains shells and other organic matter, which decompose after…