Why do Americans call it caisson? 1

[COEngineeer]

I grew up in Asia and my dad owns a marine civil enginering design/construction firm. A caisson is totally different than what we call caisson here (drilled pier). Over there is just like a precast foundation box where they put rocks in the box. What is the history with the term? Why do we call drilled piers caissons?

 

[civilperson]

The excavation under pressure greater than one atmosphere for piers was also called caisson excavation. This led to piers being called caissons, (drilled or hand dug), but the closed or open top structure used to excavate soil under water is the definition of caissons used by most engineers.

 

[JAE]

I'm from the US and have always called them Drilled Piers.

To me a caisson is a small trailer used to move ammunition by the military.

 

[TDAA]

Caisson was often used on the east coast for drilled pier(at least the people I was arround).

 

[Zambo]

to me - from UK and working in Asia - a drilled pier is a bored pile. A caisson is a shaft, it could be filled with rocks (or another fill material) as a foundation, but just as likely could remain as an empty shaft.

 

[PEinc]

Before equipment was invented to install drilled shafts, these deep foundations were hand excavated and were called caissons. In some areas of the US, drilled shafts are still called caissons. Civilperson has the most accurate explanation.

 

[youngstructural]

Hey All;

I don't know if it's actually a French invention, but however it happend, this is a French name; "Caisson" is akin to saying a "containment device"...

One of the advantages of being bilingual I suppose... Hope that helps

Regards,

YS

B.Eng (Carleton)
Working in New Zealand, thinking of my snow covered home...

 

[BigH]

There are a myriad of terms for "caisson". Drilled shafts; drilled piers; drilled-in piers; bored piles; to name a few. Different areas of the country and world call them differently. I suppose it is linked to the early history of them - the Chicago Caisson, the Gow Caisson are two that are explained in Krynine and Judd (1957).

 

[cbosy]

We call them caissons here in the city with big shoulders, Chicago!

 

[PEinc]

Caissons in Philadelphia too.

 

[emmgjld]

Caissons in Colorado, but the term drilled piers is becoming commen.

I think this is historical as much early construction was in soft soils, requiring casing. I know my Father referred to the borings in stiff, expansive clay as drilled piers and he seemed to frown upon using caissons for anything which did not have casing.

 

[eric1037]

Caissons in Michigan too. However, we try to use the term "Drilled Shafts" or "Drilled Piers" to distinguish these types of foundations from the more classical (and technically correct) definition of "Caisson".

 

[jhoulette]

In Colorado I hear both terms used. Typically the field calls them caissons while the engineers correctly refer to them as straight shaft drilled piers. I think most of the field guys I talk to came from the east coast and mid-plains. I try to correct them as nicely as possible. ;o)

 

[minorchord2000]

we call them drilled shafts here in arizona

 

[GeoEngineerOK]

We call them "drilled piers" in Oklahoma except for the OK DOT they prefer "drilled shafts"

 

[twinnell]

In North Carolina, we typically call large diameter deep shafts caissons and small diameter shallow shafts drilled piers. What do you call a belled shaft? I have only heard it called a belled caisson.
Also, we call a water retaining structure designed to keep a work enviroment dry (caisson) a cofferdam.

 

[COEngineeer]

My old man builds harbors in asia. They call this precast concrete box a caisson. They fill it with water and let it sink, then put rocks in it. Then you use this box as a foundation.

 

[BigH]

The concrete box that COENgineeer refers to are also known as caissons (perhaps it is in the argot of a harbour engineer as distinguishing from the argot of a deep foundation engineer???). Large concrete box caissons have been used in a number of the harbours in Saint John New Brusnwick.