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John Kogel
11-22-2009, 10:08 PM
In the recent court case in which a HI apparently missed some rot in the crawlspace, the engineer refers to rot in the "bent & beam". There are other references to "A-frame beams". Are they referring to beams which have diagonal timber bracing under them, so that the braces form a shallow "A" under the beam?


I'm posting a pic of the million $ house, talk about inflated prices in North Vancouver, eh?

2009 BCSC 1515 Salgado v. Toth (http://www.courts.gov.bc.ca/jdb-txt/SC/09/15/2009BCSC1515.htm)

Bruce Breedlove
11-22-2009, 10:33 PM
In civil engineering and construction a bent is a supporting structure of some sort that supports beams or girders. Below is a photo (borrowed from Ed A. Wilson, Inc. - Construction and Emergency Concrete Repair (http://www.edawilson.com/project06.html)) of a couple of bridge bents.

Scott Patterson
11-23-2009, 07:49 AM
In the recent court case in which a HI apparently missed some rot in the crawlspace, the engineer refers to rot in the "bent & beam". There are other references to "A-frame beams". Are they referring to beams which have diagonal timber bracing under them, so that the braces form a shallow "A" under the beam?


I'm posting a pic of the million $ house, talk about inflated prices in North Vancouver, eh?

2009 BCSC 1515 Salgado v. Toth (http://www.courts.gov.bc.ca/jdb-txt/SC/09/15/2009BCSC1515.htm)

Is that home on the way up to Grouse Mountain? I have been up in that part of Vancouver and the views are spectacular if you are in the right place!

bill cook
11-23-2009, 08:31 AM
Usually a preformed laminated support
Bill cook

Corn Walker
11-23-2009, 09:23 AM
In the recent court case in which a HI apparently missed some rot in the crawlspace, the engineer refers to rot in the "bent & beam". There are other references to "A-frame beams". Are they referring to beams which have diagonal timber bracing under them, so that the braces form a shallow "A" under the beam?

No, if you read the description of the house in the judgement you'll see the original structure was an A-frame house.


The Plaintiffs purchased a property in North Vancouver having a building lot that had a steep slope along the southern perimeter of the lot (“Property”) and a house consisting of an A‑frame structure built during the early 1960s and an addition that was constructed in the late 1980s (“House”)

John Kogel
11-23-2009, 11:38 AM
In civil engineering and construction a bent is a supporting structure of some sort that supports beams or girders. Below is a photo (borrowed from Ed A. Wilson, Inc. - Construction and Emergency Concrete Repair (http://www.edawilson.com/project06.html)) of a couple of bridge bents.Thanks Bruce, the bents I take it are the short beams which support the long beams. That's jogging the memory bank now. (So warm up the TV, it's time for "You Bet Your Life"):)

CW - Thanks, yes they do refer to an A-frame structure with rot in the rafter ends, so OK the A-frame beams are under the A-frame.

Scott, I don't know the address, but generally any home on a slope in North Van has a spectacular view.

Jerry Peck
11-23-2009, 07:36 PM
The best definition I've came across trying to find one on the internet:
http://en.wikipedia.org/wiki/Bent_(structural)

Bruce showed a "straddle bent": What is a "straddle bent"? - misc.transport.road | Google Groups (http://groups.google.com/group/misc.transport.road/browse_thread/thread/4bbe3f05af1784ee/cf156aa75157cb2f?lnk=raot)

Bridge Inspection Definitions - Subcommittee on Public Affairs (http://www.iowadot.gov/subcommittee/bridgeterms.aspx#b) :


Bent
Part of a bridge substructure. A rigid frame commonly made of reinforced concrete or steel that supports a vertical load and is placed transerse to the length of a structure. Bents are commonly used to support beams and girders. An end bent is the supporting frame forming part of an abutment.

Each vertical member of a bent may be called a column, pier or pile. The horizontal member resting on top of the columns is a bent cap. The columns stand on top of some type of foundation or footer that is usually hidden below grade.

A bent commonly has at least two or more vertical supports. Another term used to describe a bent is capped pile pier. A support having a single column with bent cap is sometimes called a "hammerhead" pier.

Corn Walker
11-23-2009, 08:51 PM
The best definition I've came across trying to find one on the internet:
http://en.wikipedia.org/wiki/Bent_(structural)

Bruce showed a "straddle bent": What is a "straddle bent"? - misc.transport.road | Google Groups (http://groups.google.com/group/misc.transport.road/browse_thread/thread/4bbe3f05af1784ee/cf156aa75157cb2f?lnk=raot)


Finally, something I know about.

First, the "bent" is the combination of the columns and the support beam that ties the columns together. It is used to provide support to the longitudinal beams that in turn support the roadway deck.

What Bruce showed is not a straddle bent. A straddle bent refers to a type of bent used to get around a situation where the bent column would cause an obstruction (such as on fly-over ramps where the column might land in the roadway below). The straddle bent, as it's name implies, straddles the roadway or other obstruction. It is usually constructed of steel, although it could be constructed of reinforced concrete as well.

Here's an image of three types of bents - the one closest to the viewer is a straddle bent. http://www.roadstothefuture.com/I64-I295-Int-Feb0109-14.jpg This particular straddle bent is flush with the top of the roadway beams. Others may support the roadway beams from below as with the single and multi-column bents also in the picture.

chris mcintyre
11-23-2009, 09:29 PM
O.K. I'm confused,(not uncommon), what exactly is a bent? Or are both correct?


the bents I take it are the short beams which support the long beams.

Corn Walker
11-24-2009, 09:34 AM
O.K. I'm confused,(not uncommon), what exactly is a bent? Or are both correct?

A bent is the short beam plus the column(s) which together support the longer beams.

The only time I've come across the term bent was in engineering, specifically bridge engineering. None of my architecture books or professors ever mentioned the term.

The Wikipedia entry is interesting, and timber frame construction is something we didn't spend a great deal of time on. However their description of a "bent" is similar to what is used in bridges. A bent is a "system" much like a foundation is a "system" - it's not just another name for a beam.

edit:


None of my architecture books or professors ever mentioned the term.

Actually, I take that back - prompted by your Wikipedia image, I went through my architecture book that has a section on timber frame construction and they do use the term bent. Still don't think my prof mentioned the term; instead we identified the various pieces that make up the bent (e.g. straining beams, girt beams, knee braces, struts, principal posts, and queen posts) but I don't think we spent more than 15 minutes talking about timber frame construction.

A.D. Miller
11-24-2009, 09:53 AM
So then, there was a bridge under the house in question?:confused:

Corn Walker
11-24-2009, 10:16 AM
So then, there was a bridge under the house in question?

I think you can think of a "bent" as being the system of columns and beams and struts that together support the "longitudinal" beams. For example, in a bridge you might have a single column and beam that supports the deck beams.

In timber frame construction, the longitudinal beams the bent supports would be the floor joists and roof purlins.

A.D. Miller
11-24-2009, 10:22 AM
From Webster's:

bent: a framework transverse to the length of a structure (as a trestle, bridge, or long shed) usually designed to carry lateral as well as vertical loads.

chris mcintyre
11-24-2009, 08:08 PM
A bent is the short beam plus the column(s) which together support the longer beams.




A bent is a "system" much like a foundation is a "system"


Ahh.....the light just came on. Thanks!

Bruce Breedlove
11-24-2009, 09:21 PM
As I stated in the first reply to this thread, a bent is a supporting structure for beams or girders. I studied bents in some of my civil engineering classes at Georgia Tech in the '70s so the term is not new to me.

I have been a member of Tau Beta Pi for over 30 years. Tau Beta Pi is an engineering honor society. They use a bent for their logo. When I became a member I was given a bronze bent to polish and keep as a memento of my membership. (See photo. Mine does not have the lettering.) I also receive the quarterly magazine published by Tau Beta Pi. What is the name of the magazine? The Bent.

Steve Frederickson
11-25-2009, 09:01 AM
I also receive the quarterly magazine published by Tau Beta Pi. What is the name of the magazine? The Bent.


So you get bent quarterly? :)

Bob Harper
11-25-2009, 06:41 PM
Chris's pic in post #9 has it. In colonial times, buildings were constructed post and beam. Each section or "bent" was pre-assembled on the ground then raised as one unit then tied into the adjoining one like slices of bread.

Check with timberframers and they'll fill you in on their lingo. I have Tedd Benson's first book, The Timber-Framed Home where on page 22 it defines a 'bent' and what we might call a 'frame'. The large beam connecting the outer post to an inner one is called "bent girt" which might refer to what the engineer was referring to in the OP. What's really amazing is seeing these massive bents raise with site constructed 'A' frames and gin poles instead of modern cranes.

When the barn or building was raised and locked together as one unit, they tied a short evergreen on the kingpost as the "topping off". This was for good luck and a chance for the carpenters to admire their handiwork before closing it in. Some call this the "whetting bush".

Bob

Bruce Breedlove
11-25-2009, 07:35 PM
So you get bent quarterly? :)

Actually a little more often than that. :D