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Question
The figure given below shows the cross-section of a concrete structure. Calculate the area of cross-section if AB = 1.8 cm, CD = 0.6 m, DE = 0.8 m, EF = 0.3 m and AF = 1.2 m.
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Solution
The diagram is redrawn as follows:
Here
AF = 1.2 m, EF = 0.3m, DC = 0.6m, BK = 1.8 - 0.6 - 0.3 = 0.9 m
Hence,
Area of ABCDEF = Area of AHEF + Area of HKCD + ΔKBC
= 1.2 × 0.3 + 2 × 0.6 + `1/2` × 2 × 0.9
= 0.36 + 2.1
= 2.46 sq.m
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