Test: Column Design - Civil Engineering (CE) MCQ

When the line of action of the resultant force doesn’t coincide with the axis of centre of gravity then it is called eccentrically loaded column. An eccentrically loaded column has to be designed for combined axial force and bending moments.

o column can have a perfectly axial load. There may be some moments acting due to imperfection of construction or due to actual conditions of loading. Hence IS 456 -2000, recommend eccentricity of 20 mm.

The minimum diameter of the longitudinal bars provided in the column is 12 mm and the spacing of longitudinal bars measured along the periphery of the column shall not exceed 300 mm.

The effective lateral support is given by transverse reinforcement either in the form of circular rings or by lateral ties. The ends of transverse reinforcement shall be properly anchored.

Ground service reservoirs are constructed at ground level and mainly used to store water. They are generally constructed with masonry (or) RCC slab. These are also known as surface reservoirs or not elevated reservoirs.

In grid iron systems, there are no dead ends hence stagnation of water and its consequences are eliminated. The water is kept in good circulation due to the absence of dead ends. The system is suitable for well planned towns.

In a circle system, the entire locality is divided into either rectangular (or) circular blocks. The water mains are laid along the peripheral roads with sub mains branching out from mains. This system is also known as ring system.

Effectively held in position and fixed against rotation in both ends is 0.65 l.

The strength of column with helical reinforcement Shall be 1.05 times the strength of similar column with lateral ties, provided the ratio of the volume of helical reinforcement to the volume of the core shall not be less than 0.36(Ag/Ak – 1) fck/fy.

According to IS 456-2000, clause 26.5.3, the minimum number of longitudinal bars to be provided is 4 for rectangular columns and the minimum number of longitudinal bars to be provided for circular columns is 6.