Lateral ties in RC columns are provided to resist buckling of longitudinal steel bars.

Explanation:
RC columns are usually subjected to axial compression forces along with bending moments and shear forces. Due to these forces, the longitudinal steel bars in the column tend to buckle. Buckling is a phenomenon in which a slender member fails due to compressive forces acting on it. Buckling reduces the strength and stability of the member. To prevent buckling of the longitudinal steel bars, lateral ties are provided in RC columns.

Lateral ties are steel bars that are placed around the longitudinal steel bars at regular intervals along the length of the column. They are usually in the form of closed hoops or spirals. The lateral ties resist the buckling of the longitudinal steel bars by providing lateral support.

The lateral ties also provide confinement to the concrete inside the column. When the column is subjected to compressive forces, the concrete tends to expand laterally. The lateral ties prevent this expansion and confine the concrete, which increases its strength and ductility.

In addition, lateral ties also increase the ductility of the column. Ductility is the ability of a material to deform plastically before it fails. The lateral ties ensure that the column undergoes ductile failure rather than brittle failure. Ductile failure is desirable as it gives warning signs before the ultimate failure, which allows for evacuation and repair.

Therefore, lateral ties play an important role in ensuring the stability and strength of RC columns.

The role of lateral ties is to prevent premature buckling of bars, improve strength, to provide resistance against shear & torsion, to hold bars in position during construction etc.