There are many uncertainties in a reinforced type structures. We assume many things that even not possible in actual.
These are listed below;
- First and the common uncertainty that mostly occurs is the lack of skilled labor. If labor is not skilled then, it is very difficult to maintain dimensions. Dimensions may changes during the concrete pouring and this opt to be very dangerous.
- May be there would be an uncertainty in actual dead loads than the calculated loads.
- We are assuming for linear deformation, but may be there will be a wind effect, most probably deformation not goes linearly.
- May be there will be a variation in live loads than designed one. Therefore, to overcome this affect a factor of safety is applied to the structure strength.
- May be there will be a difference in actual member and designed member.
- Reinforcement in concrete may be not in a proper position.
- If position of aggregates will not be proper than there will be a variation in strength of actual member than the designed one and due to this material strength will also be different