Sectional Properties. Rectangle - 4 hollows
SOM-SEC-EN
Cross-section width: 68 cm; cross-section height: 16 cm; hole diameter: 12 cm. Arrange the holes uniformly so that the distances between adjacent holes and from the outer holes to the left and right edges are equal.
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About this task
This task focuses on determining the geometric properties of a rectangular cross-section containing four equally spaced circular holes. Students calculate the net cross-sectional area, centroidal moments of inertia about the horizontal and vertical axes, section moduli, and radii of gyration. The exercise reinforces the analysis of composite sections by combining the properties of simple geometric shapes and applying the parallel-axis theorem. It is suitable for strength of materials, engineering mechanics, and structural design courses where accurate evaluation of section properties is essential.