Lemme learn too

Sir, I disagree with your first point.

If the foundation is of concrete, the strength actually likely to increases (unless there is an unusual activity in the soil that corrodes the concrete). Structural steel connections may have to to be rechecked.

Practical idea.

I practice in qatar but I assume those NDT tests are not so cheap in Nigeria.

Barselonia:
Okay
....let's go this way
although u need an engineer to visit the site for feasibility sstudy first...

but let me give u my suggestion;

u said u want to increase the warehouse height: from the initial building height now,chain tthe building round (meaning put a beam round )before adding the new block..

tthen secondlly create a new columns at some strategy points, the serve two main purpose
1. to carry new beam u want to introduce on the old wall
2. to carry the steel roof u want to introducee



integrity test in Nigeria..... forget that one...

Its better if u can get the accurate mix used for the foundation if not take a sample of part of exposed foundation for crush test or you go for underpining where a more stronger foundation will be cast under the existing one without demolising the structure and at the same time dditional stronger pillars can be introduce to the walls at intervals to carry the additional loads ,for more informations u can reach us at nobleico2002@yahoo.co.uk

Integrity tests on already erected structures are done using the non-destructive compressive strength test.
To do that you have to be very sure of the true positions of the beams and columns that make up the frame structure.
If the building is abandoned,then I guess it's pretty old ,so there will be the need for the structural drawing to be examined (and even at that,you have to be sure that it was built according to design).That's as far as integrity test on the building goes.

However,note that the foundation of the existing structure was designed to carry a specified load value,hence if you don't have the structural drawing and you're not sure if it was built to that spec,then no need to start wracking your brains on how to reinforce the structural frame.
My advice is either you just renovate the structure to give it a face lift or if it's a must that you have more floors,please get a excavator to pull down the existing structure and a new one with as many floors as you want can be designed for you

sheddo619:
A building diagnosis needs to b done by trained professional though I think good underpining needs to b done to the foundation.(A building engineering student thought sha), let's just wait for professionals to come offer a relevant solutions.

bro der is no such tin as a buildin engineer is either ur a buildin technologist(a certified builder in practice) or a structural engineer (civil engineer) underpining is mstly used wen d foundation or soil bearing capacity is unstable d depth of d foundation is foundation increase to prevent total failure of d structure. I'll advice dat a redesign of d structure is made takin in consideration all d various element and components in place! D drawins made shud b handed over to a structural engineer to carry out analysis of d structure in order to knw loads d prevent structure can carry n if need be weda or nt reinforced concrete columns or steel stanctions wil b introduced at certain points at regular interval within d structure. To effectively carry d new loads dat wil b imposed on it. So invite a proffessional

It is not easy to do any structural analysis with the meagre information you gave as we are not even sure of the factors of safety considered by the original designer. For instance, information may be required on:
(1) existing column bases dimensions and conditions
(2) column types e.g. steel stanchions or reinforced. concrete and dimensions/conditions
(3) Sizes, conditions and type of existing beams
I would strongly advised that you locate an experienced structural engineer before embarking on the proposed remodelling.

For how long has the building been?
Does the blocks have missed growth all over it?
How closed its the building to any water body such as river, stream or sea?
Is the proposed renovation just to increase the floor-ceiling height?
What is the present roofing material made of?
What roofing member and cover is proposed for the new roof?

This question that needs to be answer before anything can be done.

You can contact me on 08033913204

Thnx all for your contribution.

Additional information: The columns are made of steel(stanchion) conected to the steel roof.The structure is just 6m high and wants to be increased to about 8-10m.

SafetyFirst:
There are non destructive tests for reinforced concrete structures (Ultrasonic pulse velocity test and Schmidt hammer test). Either of these tests will give you the structural integrity of the structure.

Where is the structure located?



For more information, contact me.
We are into Quality Control (Materials Testing)

Yes Ultrasonic Test can be carried out on the building.

latolak:
Practical idea.
I practice in qatar but I assume those NDT tests are not so cheap in Nigeria.

I dey tell u... were d material or equipment to use

Babangida70:
Buhari is a man of INTEGRITY so I guess you should ask him

Abacha did not STOLE awa money.. Buarri 2008

Very soon, the World Bank will return $320m illegally taken away during Abacha regime .... Buarri 2016.

dahaz:
pls this is for expirience and practical engrs.The height of an abandon warehouse is to be increased and the steel roof is to be replaced with a new one. In the absence of the as-built drawing, how do you evaluate if the foundation will be able to carry the additional loads and the new roof?

Structural analysis
Bending moment, compressive strength.

The dead and live loads are to be calculated and it may require additional support in terms of column or if the foundation must be touched, it should be expanded to dissipate the load on it.

Don't do it on your own
Employ the services of an Engineer not building technicians and technologists.
I wouldn't charge much so would they plus it comes with guarantee.

SafetyFirst:
There are non destructive tests for reinforced concrete structures (Ultrasonic pulse velocity test and Schmidt hammer test). Either of these tests will give you the structural integrity of the structure.

Where is the structure located?



For more information, contact me.
We are into Quality Control (Materials Testing)

Kindly send me you mobile no. I need some information on the Schmidt hammer.

Thank you.

From your post it appears your are only interested in the foundation, but other axial load carrying members that transmits the load to the foundation also need to be checked, as is all other members as the building is of age. This is a task you need an expert to handle as it can not be solved over the social network. The cost of a comprehensive integrity check is not as expensive in Nigeria as you might think. That is what we do, you can contact me on gemedsengineering@mail.com. for proper briefing.

latolak:
You'll have to refer to the laboratory technicians to give you a range of options available. NDT tests will be the best.

Bear in mind that you can excavate along the face of your foundation to know the size of your footings. You can along expose the concrete cover to see the rebar details.

Based on your deduction of the as built details, you can redesign.

If its a simple frame without a suspended slab (which i think it is), you may have to add a few footings to take more load from the roof.

One question. Are you simply replacing the roof? If you're not going to add any extra loading then there's little to worry about.

This is one of the best I have read as compared to others above..
And it's a simple method which will cost very little.
You did well.

But I wanna ask what if it's a duplex that hasn't been roof but have been abandoned for so long a time, and the new client who just bought the place wants to do a test to ascertain it's stability

I really understand your predicament as a professional in structural stability investigation, it is better you gather an empirical data which will guide you in making informed decisions.

1. Carryout a structural stability test using e.g PuV or schmidt hammer.
2. Carryout a subsoil investigation on the substructure(CPT/SPT).
3.Carryout an historical survey of the structure e.g checking years of abandonment, defects, serviceability and functionality levels.

My firm just did a structural investigation on a burnt bridge in shoddily-apapa expressway.

if you want further information you could reach at: fmbbs437@gmail.