ademoladeji:


Bridges are not buildings and I can tell you the structural integrity can not be hampered by the fire incident that lasted less than 6hrs as there was no hit/impact.

In fire, concrete performs well – both as an engineered structure, and as a material in its own right. It has the highest fire resistance classification (class AI) under EN 13501-1:2007- A1:2009.

Concrete does not burn – it cannot be set on fire and it does not emit any toxic fumes when affected by fire. Concrete is proven to have a high degree of fire resistance and, in the majority of applications, can be described as virtually fireproof. This excellent performance is due, in the main, to concrete’s constituent materials (cement and aggregates) which, when chemically combined within concrete, form a material that is essentially inert and, importantly for fire safety design, has relatively poor thermal conductivity. It is this slow rate of conductivity (heat transfer) that enables concrete to act as an effective fire shield not only between adjacent spaces, but also to protect itself from fire damage.

bixton:



Fire does not affect concrete per se. But in the triangle/tetrahedron of fire , we have heat.
Heat may likely have an effect on concrete/RC depending on its span and thickness. In the instance where the span/thickness of concrete is much and the absorbed heat caused by the fire when it cools in the concrete does not overlap proportionally along the span of the concrete it will result to cracks within which will become visible.


You can liken it to the local way of mining granite. In areas where igneous rocks are visible and within reach, local miners pour liquid fuel and ignite it. It's left to catch fire for some time and afterwards they go with small handy hammers and hit on the rock to cause cracks and to get the rocks into tiny sizes to be used .

ademoladeji:


The wearing course- ASPHALT of course

Now going with your submission, with raging fire with time less than 6hrs, the concrete for me is still in order.

From experience, I was opportuned to work on a burnt section of Marine beach bride, Ijora, Lagos. Both destructive n NDT were carried out in relation to unburnt section. Result shows relatively same compressive strength of concrete both for the piers, girders n deck.

We were required to produce concrete jacketting to the existing structure as need arises for increase in both static and dynamic load. Also, additional post tension cable was installed as well as replacement of bearings carried out.


Client: Federal Ministry of Works
Contractors: Buildwell Plants and Equipment
Project start date: 2nd December, 2013
My capacity: Project Lead Engineer for Contractor

ademoladeji:


The wearing course- ASPHALT of course

Now going with your submission, with raging fire with time less than 6hrs, the concrete for me is still in order.

From experience, I was opportuned to work on a burnt section of Marine beach bride, Ijora, Lagos. Both destructive n NDT were carried out in relation to unburnt section. Result shows relatively same compressive strength of concrete both for the piers, girders n deck.

We were required to produce concrete jacketting to the existing structure as need arises for increase in both static and dynamic load. Also, additional post tension cable was installed as well as replacement of bearings carried out.


Client: Federal Ministry of Works
Contractors: Buildwell Plants and Equipment
Project start date: 2nd December, 2013
My capacity: Project Lead Engineer for Contractor

dingbang:
Buhari please also evacuate petrol tankers from roads during day time. Thank you.

Organism000:

So God is dead ?

SalamRushdie:


I was talking of LASEMA and not your local govt sir ..LASEMA is the best run govt parastatal in Nigeria and they do world class job with world class equipment obtainable in any part of the world