Column base plates are used when you try to connect a column with a r. C. C foundation. The strength transferred from a steel column will be huge as the strength of concrete is less than that of steel when they are connected directly, the high load from steel gets transferred to a concrete area which will be very small to handle the high loads hence leads to punching or sinking.
Type of Base Plate, Bracket & Clump
- Base Plate With Hole
- Base Plate Without Hole
- Brackets
- Clumps
When you provide a base plate beneath a column, the load gets dispersed to a larger area and after that if is transferred to a concrete foundation hence the system is safe.
Column base in short is used to disperse load from a steel column to a concrete foundation.
Compressive strength of steel and Bearing strength of concrete has vast gap. As steel has higher strength of compression and bending, the design area of steel column work out to be less. Now, as concrete section which is going to bear the load coming from column, has less bearing strength so we need larger concrete area.
This reflects as flexural rupture or puncture due to shear if concrete section below column is significantly thin(like slab) and for thicker section(like pedestal) concrete might fail in crushing if not designed accordingly.
To overcome this effect, one column base plate is provided between column and slab base. This plate helps to distribute concentrated load of column to the slab base below.
If you understand concrete structures thoroughly, you can easily correlate base plate with isolated pad footing.