S Tests on Bricks The following laboratory tests may be conducted on the bricks to find their suitability: (i) Crushing strength (ii) Absorption (iii) Shape and size and (iv) Efflorescence. (i) Crushing Strength: The brick specimen are immersed in water for 24 hours. The frog of the brick is filled flush with 1:3 cement mortar and the specimen is stored in damp jute bag for 24 hours and then immersed in clean water for 24 hours. The specimen is placed in compression testing machine with 6 mm plywood on top and bottom of it to get uniform load on the specimen. Then load is applied axially at a uniform rate of 14 N/mm2 . The crushing load is noted. Then the crushing strength is the ratio of crushing load to the area of brick loaded. Average of five specimen is taken as the crushing strength. (ii) Absorption Test: Brick spe...
R.C.C Foundation FOOTINGS There are mainly two types of R.C.C. footings: 1. One way reinforced footings. 2. Two way reinforced footings. 1. One Way Reinforced Footing: These footings are for the walls. In these footings main reinforcements are in the transverse direction of wall. In longitudinal directions there will be only nominal reinforcement. 2. Two Way Reinforced Footings: For columns two way reinforced footings are provided. The following types of the footings are common: (i) Isolated Column Footings: If separate footings are provided for each column, it is called isolated column footing. Figure 7.3 shows a typical isolated column footing. The size of footing is based on the area required to distribute the load of the columns safely over the soil . These footings are provided over a 100 to 150 mm bed concrete. Required reinforcements and thickness of footing are found by the design engineers. Thickness may be uniform or varying. (ii...
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