The point OP is that you most definitely don't want to do a soil test. You don't even want to engage professionals for your project that's why you're here to get free advice. Brother, nothing good comes free. From my experience as a young architect, a client who wants to put up a structure as yours will cry blue-murder when given a bill of N200k to produce 'stampedand sealed approval and construction drawings', so tell me, will you be willing to pay N150k for a soil test? Second, you don't want to engage a professional structural engineer, that is why you have consulted a so-called building contractor who has no requisite knowledge about proper construction techniques and he's probably giving you a wrong advice because he wants to make more money from you. Do the right thing brother, the likes of you are making charlatans in the building industry thrive. Engage professionals and stop looking for free advice.

segcy.moor:
Bros with due respect you must be educated. So why this unnecessary confusion. The issue is as simple as ABC. Consult a geologists for soil test ! It takes less than 150k.although an experience engineer supposed to give advice on foundation to adopt but as confusion has set in.DO SOIL TEST

but u still need Structural Engineer for the interpretation of the foundation.It is not geologist that do soil test it is Geothecnical /Foundation Engineer that does it.

@fadelex. With due respect I totally disagree with you that the Guy that quote for pile (for a story building is a quack)
Damn! Have you being to arowojobe estate at Maryland. I tell you I did a project over their and the building is tilted even before lintel. I am talking about just bungalow. This happened just because the idiot that did piling we adopted didn't get to required depth. Virtually all the pilling on that environment failed because it didn't handle by competent hand.
.......u can't conclude that pilling is meant for high rise without due consideration for the nature of the land in question

If u ask me pile is foundation for all type of soil but very expensive.if it not a water logged area go fo raft except u have enough money for the pile fdn.the soil test will tell you the nature of the soil and to know if pile is a must to be use or not.hope I was very heplful to u.

ubeji: but u still need Structural Engineer for the interpretation of the foundation.It is not geologist that do soil test it is Geothecnical /Foundation Engineer that does it.

Thank you! I was beginning to wonder what a geologist has got to do with investigating ground conditions for foundation design

hi sir, am a Quantity Surveyor, it all depends on d capacity of d soil, d type of soil wi determine d type of foundation dat shud b put in place. for more info contact me on 08180011419

segcy.moor:
@fadelex. With due respect I totally disagree with you that the Guy that quote for pile (for a story building is a quack)
Damn! Have you being to arowojobe estate at Maryland. I tell you I did a project over their and the building is tilted even before lintel. I am talking about just bungalow. This happened just because the idiot that did piling we adopted didn't get to required depth. Virtually all the pilling on that environment failed because it didn't handle by competent hand.
.......u can't conclude that pilling is meant for high rise without due consideration for the nature of the land in question

Thanks and God bless U̶̲̥̅̊ fø̲̣̣я̅ this response. There is a site at Anthony, Lagos that you as a human being will sink on Ūя̲̅ own weight till knee or waist level. With just a blow, a precast pile will sink in totally till it reaches good soil. Same with another site in Mende Meryland. Not †̥☺ talk of a whole 1 storey building!

Fadelex: the engineer that quoted for pile foundation for a storey building is definitely a quack.... unless you are building an island in a river, Pile foundations are long, slender, columnar elements in a foundation that are installed into the ground.
They aretypically made from steel or reinforced concrete and possibly timber . A foundation is described as piled when its depth is more than three times its breadth.
Pile foundations are principally used to transfer the loads
from a superstructure, through weak, compressible strata
or water onto stronger, more compact, less compressible
and stiffer soil or rock at depth, increasing the effective size of a foundation and resisting horizontal loads

raft foundation is suitable for d design

Mr Aboki:



You sir have spoken like a true engineer...

Which engineering field do you rep sir?

I studied building technology...

Am impressed fellow engineers by ur contributions

richeyy:

Thank you! I was beginning to wonder what a geologist has got to do with investigating ground conditions for foundation design

ubeji: but u still need Structural Engineer for the interpretation of the foundation.It is not geologist that do soil test it is Geothecnical /Foundation Engineer that does it.

Geologists are specialists when it comes †̥☺ soil, rocks, etc. Most Civil Engineering students run borrowed courses fø̲̣̣я̅ some semesters called 'Engineering Geology'. Carrying out Soil test and Analysis and preparing the reports can be done by Geologists (atleast they study those things!).

Civil Engineers who specialize as Geotechnical Engineers though can also do soil tests but they focus more on Heavy groundbreaking constructions like dams, tunnels, bridge foundations etc. Atleast those I know.

Not all swampy area requires pile foundation as there are very solid raft designs.However the informed decision should be for a soil scientist to test for soil BEARING CAPACITY which is the test to determine the load the soil or location can carry.

Please this test is carried out by soil scientists not neccessarily Geologists.

It depends on the depth of the swamp. The first thing you need to do is to carry out a SOIL TEST. The soil test will let you know the geographic structure of the land. If the swamp is 10 feet or less, I will suggest you carry out full excavation of the swamp for the entire building area within the plot to the depth of the sharp sand beneath the ground. Then fill up with sharp sand to level up to the ground surface. After then construct about 5 planks of raft on top with partitions. Then fill the internal partitions of the raft with sharp sand before doing your german floor. I used this approach for my building at Westess or Oke-Alo estate as directed by my civil engineer. The house is standing today to the glory of God.

[quote author=Mr Aboki]


For the purpose of being proper, a Structural Engineer should not be the one to design a foundation plan. Foundation analysis should ideally be done by a Foundation engineer. Its based on the findings of the foundation Engineer that the Structural guys would base their design.[/quote

Please educate me more: who is a foundation engineer? And what is their professional speciality.

@Mr segcy and Dr Opalu (in view).... I understand your point but check dis out
Strip foundations (footings) – a linear foundation which
generally support walls.
• Pad foundations – a discrete square or rectangular
foundation supporting columns or piers.
• Raft foundations – a large single foundation supporting a whole structure.

while...
A deep foundation is used to transfer loads from a structure above ground through upper weak strata of soil to a more competent one at depth, beyond which shallow foundations become both impractical and uneconomic. The most common form of deep foundation is provided by using piles which can be categorised as either replacement or displacement.

even though I don't know d nature of d soil but from experience, I handled a plaza in Abuja few years back (central business district), some Lebanese were brought to d site and they totally condemn d soil capability of d site, they concluded d site can't take more Dan a storey building... but after we amended d raft foundation we met on ground, the building is at d 5th floor now... what we did was this, after excavating d foundation we used hardcore to fill all d sub-structure then we use wire mesh to cover it b4 d concrete work....no tilting, no vibration, no dampness...

Pile foundation is ƒσя bridges(where there is a river or the likes) you can't use that on a swampy area, raft foundation might be ok! But I had prefer you use a wide strip foundation....with enough reinforcements....and Τ̲̅ђe depth should be about 2feet 6'.....tanx



Ƒσя those saying he should consult a geologist and others...consider economy here...he might not be that bouyant!

Please go get a good foundation/structural engineer that is registered with COREN and he in turn should get a good geotechnical engineer that will carry out a comprehensive soil test on the site. the geotechnical engineer will do some useful recommendations on his report as to the most viable foundation type for ur site.

@cypost except you want to skip soil test which is just 3%(in terms of cost) of the whole project..... for me I don't think its professional!
For you to determine the foundation to use; you have to carryout soil test-from the result of the soil test and the architectural drawing, the structural/ civil engineer can determine which foundation to use either a slab raft or slab and beam raft or cellular raft or pile foundation by transfering dead and live loads from the roof-column-slab-beam-column-foundation.
If you decide to skip soil test and bury your fellow compatriots inside a swampy or marsh soil.....God is watching you.

this topic is very educative this is one of the best topic i ever come across in nairaland. the right anwer has been given. so dt be comfuse again. greeting to all nairalanders.

[quote author=opalu]Most people do not know who a Structural Engineer is. As a COREN registered Civil/structural Engineer who by His grace rounding-up his Doctorate (@Unilorin), I have sworn †̥☺ uphold and enlighten the society abt d profession wherever I find myself.

I"d be brief and simple fø̲̣̣я̅ now. Civil Engineering has many areas of specialization like: Geotechnics, Structural, Airport, Railway, Highway and Water (put 'Engineering at their fronts fø̲̣̣я̅ me).
As a Structural Engineer, you basically determine the load/forces/stresses via structural analysis and proceed †̥☺ carry out the structural design: whereby the Engineer selects the sizes, types, positions etc of the members †̥☺ use †̥☺ withstand the anticipated ultimate loads with respect †̥☺ relevant Codes taking account o... Pile + raft foundation is a waste of resources the building is of relatively small load a well constructed STRIP foundation will serve(for a pro engineer)

Well built strip foundation is the best as evenly spreading load of the building over the area is paramount otherwise the building will deform

Consult a COREN structural engineer not a contractor.
A good structural engineer will request for a soil investigation from which the type of foundation can be determined. The option of the structural engineer would be fit and economical, without error or wastages.

Consult me:
Etcurts Solutions Limited
edwin.structures@gmail.com
07 037 38 38 82.

ifeanyi83: The point OP is that you most definitely don't want to do a soil test. You don't even want to engage professionals for your project that's why you're here to get free advice. Brother, nothing good comes free. From my experience as a young architect, a client who wants to put up a structure as yours will cry blue-murder when given a bill of N200k to produce 'stampedand sealed approval and construction drawings', so tell me, will you be willing to pay N150k for a soil test? Second, you don't want to engage a professional structural engineer, that is why you have consulted a so-called building contractor who has no requisite knowledge about proper construction techniques and he's probably giving you a wrong advice because he wants to make more money from you. Do the right thing brother, the likes of you are making charlatans in the building industry thrive. Engage professionals and stop looking for free advice.

U can't be too sure in your assertion, d drawing has been done and paid for. By asking questions atimes u r guided on the best solution to an issue. Bear in mind also that professionals sometimes disagree on d best approach to resolve issues. Nothing is straight jacket as such. So it not a case of not wanting to expend money on pros but being a bit informed and getting value for money by making d right decisions
Tnx for ur input all d same

oloriIT: It depends on the depth of the swamp. The first thing you need to do is to carry out a SOIL TEST. The soil test will let you know the geographic structure of the land. If the swamp is 10 feet or less, I will suggest you carry out full excavation of the swamp for the entire building area within the plot to the depth of the sharp sand beneath the ground. Then fill up with sharp sand to level up to the ground surface. After then construct about 5 planks of raft on top with partitions. Then fill the internal partitions of the raft with sharp sand before doing your german floor. I used this approach for my building at Westess or Oke-Alo estate as directed by my civil engineer. The house i standing today to the glory of
God.

You are very close to truth. I have discuss this approach as best alternative to pilling regarding upcoming project at ikate lekki


You are very close to true. I have discuss thisas. B

adonismuller: Pile foundation is ƒσя bridges(where there is a river or the likes) you can't use that on a swampy area, raft foundation might be ok! But I had prefer you use a wide strip foundation....with enough reinforcements....and Τ̲̅ђe depth should be about 2feet 6'.....tanx



Ƒσя those saying he should consult a geologist and others...consider economy here...he might not be that bouyant!

I wish to know your area of specialization
before Comments

Fadelex: the engineer that quoted for pile foundation for a storey building is definitely a quack.... unless you are building an island in a river, Pile foundations are long, slender, columnar elements in a foundation that are installed into the ground.
They aretypically made from steel or reinforced concrete and possibly timber . A foundation is described as piled when its depth is more than three times its breadth.
Pile foundations are principally used to transfer the loads
from a superstructure, through weak, compressible strata
or water onto stronger, more compact, less compressible
and stiffer soil or rock at depth, increasing the effective size of a foundation and resisting horizontal loads

raft foundation is suitable for d design

You are wrong. There is no given length for piles. They can be as short as necessary and no they don't have to reach bearing strata. You can pile just to densify the soil.

The building is small so I think a very important factor is the availability of equipment. If you can somehow lay your hands on a rig piling may be cheaper and quicker. Rafts are low tech solutions but are grave money pits.

Reference:

You are wrong. There is no given length for piles. They can be as short as necessary and no they don't have to reach bearing strata. You can pile just to densify the soil.

the length varies from 300mm to 3.0m and you said they don't have to reach d bearing strata, then what's d essence of using pile when it won't reach d bearing strata.... bearing strata in dis case could be a rock or more solidified soil... if the pile is gonna be suspended then there's no case using it cuz the aim of d pile has been defeated

Reference: The building is small so I think a very important factor is the availability of equipment. If you can somehow lay your hands on a rig piling may be cheaper and quicker. Rafts are low tech solutions but are grave money pits.

Rafts are alternatives, not low tech or inferior to pile foundations.

Mr Aboki:


Rafts are alternatives, not low tech or inferior to pile foundations.

Did not say they are inferior but in our largely unsophisticated engineering environment we often go for rafts which are more expensive but more practical. We lack equipment in this country. Piling is far cheaper.

Am a geologist by profession and I'll gladly help u in a little way I can,I'll recommend u. A raft foundation, though but are used in areas where the ground or the soil is weak but pile foundation is mainly used for multi storey buildings, and since u'r intending to build a flat, I'll suggest u go for raft foundation reinforced with a thickness of up to 30cm embedded about 30cm into the ground, make sure the foundation covers the whole area and may even extend beyond it. You can ask any question if u have any, I'll be here for u,

Fadelex:
the length varies from 300mm to 3.0m and you said they don't have to reach d bearing strata, then what's d essence of using pile when it won't reach d bearing strata.... bearing strata in dis case could be a rock or more solidified soil... if the pile is gonna be suspended then there's no case using it cuz the aim of d pile has been defeated

No you have friction piles that do just fine. Just like trying to place a nail into a very soft wall. You can either use a longer nail, drive a short nail at an angle to increase surface area or use a screw nail that also offers higher surface area and better grip. The key is 'friction' which generates 'pressure' which carries load. There are many types of piles. Like the ladies say. It is not the length. It is how you use it.

wandevincent: Am a geologist by profession and I'll gladly help u in a little way I can,I'll recommend u. A raft foundation, though but are used in areas where the ground or the soil is weak but pile foundation is mainly used for multi storey buildings, and since u'r intending to build a flat, I'll suggest u go for raft foundation reinforced with a thickness of up to 30cm embedded about 30cm into the ground, make sure the foundation covers the whole area and may even extend beyond it. You can ask any question if u have any, I'll be here for u,

As a geologist that you are, I will believe its unethical professionally to make such specifications.