existing structure overload!

[oneintheeye]

A bit of possibly a hypothetical question here. We have been doing more and more assessments of existing structures for not what I would say is change of use exactly but increased loading. New loading pattern etc. A couple have been very close to overload. Some of the new loading conditions have already been applied before the check. My question is this;

1) Say the new load (already placed) shows that the reinforcement in the slab in theory fails, but the slab is standing. The allowable design stress is less than calculated. But the structure is standing. The calculated material stresses are less than the manufactured 'target' for the time which (with design safety factors) account for the fact that the slab is ok. In the (somes) client s eyes I would look crazy for insisting remedial works are undertaken. How is the best way to handle this?

 

[SlideRuleEra]

What I am getting at is to a non engineer saying that the structure needs remedial work when he can see it standing there may seem a bit strange.

As long as you are working with intelligent, concerned individuals this can be done. It just takes a creative approach to demonstrate engineering principles with simple models (a house-of-cards, simplified drawings, verbal labels, etc.)

http://www.SlideRuleEra.net

http://www.VacuumTubeEra.net

 

[vandede427]

I agree, tell the client the results of your analysis and give a recommendation (don't insist on or direct any work), let them decide what to do with their own building.

Less than 5% overstress, you're probably ok. More than 5%, still make a judgement call. More than 10% overstress, strongly recommend modifications.