Thread: Foundations or footings??

I reckon I'll have to see the constructions when I get to Thailand. Just wondering what carries the load of the roof rafter or joist?

Originally Posted by smullenpe

I reckon I'll have to see the constructions when I get to Thailand. Just wondering what carries the load of the roof rafter or joist?

I would have answered this earlier but have just seen this, and even though it has been awhile that the OP placed his inquiry, it nevertheless merits an answer.
Without getting too technical, (and asking in advance for Boussinesq's and AASHTO's forgiveness for the vagueness), in the LoS, loads pertaining to a structure usually rest on friction piles somehow* hammered into place.
This because of the soil types, speaking generally from limited experience in and around Bangkok, which are of the silty-, sandy-, loam/clay variety and hence therein lays their relatively low load bearing capacity.

Friction piles built into pile groups are used for larger structures in order to augment the load bearing capacity.
Also piers are employed on bridge and overpass works and in other supports structures like Bangkok's sky train project.

Always from my limited observations and building experience here in the LoS, soil testing even in major construction work is virtually/totally absent in low-rise housing projects, individual homes etc; is not a prerequisite -- let me rephrase that -- it's practically nonexistent. Building inspectors, never/rarely visit a site. If they do, it is because you have sent a driver to pick them up; a few clam$ will clear most of the paper work "site" unseen.

Safety First signs are hung throughout the realm but horrific accidents happen here on a daily basis, nothing that one million baht or thereabouts can't cure (we're talking here death cases, well advertised by the media - at the present exchange-rate equivalent to about 25,000 US$. Lopping off of limbs, loss of eyeballs and phalanxes especially of up country construction workers carry of course a much lower price and are much less advertised given the frequency. The individuals in question are considered to be a rather expendable breed by their thai-chinese and thai-indian employers - duh!)

This is a very short and generic overview and only one part of the story regarding what keeps buildings here, standing upright. Now getting into structural design, reinforced concrete design... nah! I don't want to get into this right now... later maybe... another nightmare!

*Somehow = Piles here are known by the general thai public as "poles", have a square cross-section; and they can be any length from around a couple of meters to 5-6 m or probably more. Pile drivers on small projects are a simple combustion engine powering a winch, around which are wound a few yards of cable passing through a pulley, there is a weight that crashes down unto the "protection cap" placed over the pile head. The manual engagement and subsequent release of a clutch procures the up-and-down movement of the "hammer".
It's not uncommon to observe "poles" being driven into the soft soil, using human body mass weight as one of our own beloved posters , Mr. Hillbilly here has experienced firsthand and has kindly photographically documented for posterity, while adding an extra room to his own dwelling.

Originally Posted by smullenpe

Originally Posted by dirtydog

First one, generally footings and beam work as the walls are not load bearing. can be made to any height within reason.

I'm a structural engineer and it's first time I heard in my life that footings and beam as walls are not load bearing. I can understand if it was a slab on grade but foots? What's going to carry the load to the soil. Normally, you do your utilities before you pour floor slab. And if you are going to excavate to have basement or cellar, you do need a foundation wall of some sort including mat foundation or footings depending on the soil condition.

If you read DD's post properly, you'll see that he says that the beams are load bearing, that's what they're there for. So they make a steel reinforced concrete frame and fill the gaps with block or brick. This is the same for a bungalow or a skyscraper (they often use glass instead of block/brick though).

yeah, the coolest thing, when you want to remove a wall just take a 10 lb sledge and knock out the bricks. No such thing as load-bearing wall here.

Or a 25lb soi dog.

(Put sheets down first to avoid staining)

I drove through Khao Lak earlier this year and saw several houses where the concrete skeleton remained intact after the tsunami wave had gone straight through the house taking all the brick work, and presumably everything else inthe house, with it.

Just had soil test done on my land on the river near phnom penh.
Khmers generally dig holes for column footings,columns are the load bearers obviously.
Footing maybe a metre square reinforced concrete.Columns then linked by beams around perimeter and crosswise,beam above ground maybe 250mm square.
If footings or columns not joined by beams you maye get differential subsidence where one or more columns can sink or move on their own.
I am building a suspended slab on columns with crap red khmer bricks and a steel framed and sheeted roof-relatively lightweight construction.
Khmer beams are 200 wide by 400 deep and columns are usually 200 square.
To be safe I need piles,five to a column about 4 meters deep with a column cap on top about 900mm square linked with the above ground beams.
I initially resisted piles as houses around me are bigger and dont have them but will the buildings last?
Piles are only $4 a lineal meter installed so 15 columns with five piles each at 4 meters is $1200.
Not bad for security.
All up my piles,columns,suspended slab and level one columns for a house 8 metres by 14 meters will be about 10k.
Bricks are only $300 per 10,000.
Steel concertina security doors are $400 a set for 2m high by 2400 wide-I need two sets.
A louvre window with steel security grill,one metre wide by 1400 high is only $35-I need ten of those.
Internal hardwood door in frame is $60.
4mm roof sheeting is $4 a square meeting,50mm insulation is $5 a sq metre.
Galtube 1.4mm thick 85mm by 35mm for rafters at 6 meters long is $12.
So although concrete and reo is almsot a world price other stuff is cheap.
Oh and labour,six men at $5 a day each for three months is $2700!!!
Oh and beer on top of that of course.

Originally Posted by dirtydog

I believe you mean a well, 50 meters if memory serves me correct,

Is that right? Ours is much closer, the water isn't potable, but it's used for washing up. Should I worry?

Engineer now going with raft slab with thickening at edges and down the centre to support the columns.