15 questions. Tap an option to check it instantly, then read the solution.
Practice SSC JE and other civil engineering exam questions on columns and struts: Euler's buckling theory, crippling (critical) load, effective length for different end conditions (theory and IS 800 / IS 456 values), slenderness ratio and radius of gyration, short columns under eccentric load, the middle-third rule and the core (kern) of rectangular and circular sections, plus a few related questions the book places in this chapter. Tap an option to check it, then open the full explanation for each question.
Question 1Easy
As per Euler's theory, buckling of a long column occurs when ______ (P = applied axial load, Pcr = crippling load by Euler's theory).
Answer: A. The point load shall be applied within the rhombus located at the centre with diagonals 1.33 m × 0.66 m to ensure no tensile stress develops in the column cross-section.
Core of a b × d rectangle = rhombus with diagonals b/3 and d/3 = 4/3 = 1.33 m and 2/3 = 0.67 m.
Question 3Easy
As per Euler's theory, for which of the following end conditions is the longest effective length of a column obtained?
Answer: C. When one end of the column is fixed and the other end is free
Fixed–free: le = 2L, the largest of the four standard cases.
Question 4Medium
The actual length of a prismatic compression member is 3 m. Calculate its effective length if one of its ends is restrained against both translation and rotation, and the other end is restrained against rotation but free to translate.
r = √(I/A); for the same area, I grows with the square of the distance from the centroid, so r is largest when the material is farthest away.
Question 6Medium
Four columns are identical in all parameters except end conditions: (i) both ends hinged, (ii) both ends fixed, (iii) one end fixed and the other free, (iv) one end fixed and the other hinged. Arrange them in ascending order of load-carrying capacity.