Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

RE: retail center lateral system (3 sided masonry)

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Although I try to avoid buildings with one side completely open, I agree with Brian Smith that such designs are not that uncommon.  For applied loads in the N-S direction, the center of rigidity is at the center of the shear wall on the west side.  The applied loads cause torsion about that wall.  The entire set of shear walls must then be accounted for - the torsion will be resisted by the the north and south walls, in the form of a couple.  I would design the diaphragm to transmit the force couple to the north and south walls as well as the N-S shear reaction to the west wall.
 

William C. Sherman, PE
(Bill Sherman)
CDM, Denver, CO
Phone: 303-298-1311
Fax: 303-293-8236
email: shermanwc(--nospam--at)cdm.com

 


From: Brian K. Smith [mailto:smithegr(--nospam--at)bellsouth.net]
Sent: Tuesday, May 09, 2006 8:43 AM
To: seaint(--nospam--at)seaint.org
Subject: Re: retail center lateral system (3 sided masonry)

Brian,
 
    Designing a 3-sided, open front structure is relatively common.  There is some verbage in the IBC (2305.2.5) allowing it to be designed with a wood diaphragm.  I do it all the time with metal deck.  My approach is relatively conservative in that I assume the deck to be totally cantilevered from the back wall.  I then check bending and shear deflections, moments, and shears using deep beam theory from Roark's.
 
Brian K. Smith, P.E.
 
----- Original Message -----
From: Brian
Sent: Tuesday, May 09, 2006 9:21 AM
Subject: retail center lateral system (3 sided masonry)

I need some help to settle an office dispute.

Currently we have a 1-story retail center project in
our office.  The building is rectangular and approx
300 ft running in the NS direction and 90 ft in the EW
direction.  The entire East face of the building is
storefront glass (300 ft) and wraps about 20 ft on the
North and South faces.  The rest of the building,
which consists of the entire West face and the
remaining portions of the North and South face, is
contructed out of 8" masonry.  The roof is constructed
of joists, joist girders and metal deck and there are
interior steel columns and steel columns at the
storefront to support.

Our differences come about for the lateral system in
the long direction of the building.  My co-worker
would like to design this building without a lateral
frame on the East face and rely entirely on the
masonry shear wall on the West face.  However, I
believe that a lateral frame is required because I do
not believe the metal roof deck can transfer the
entire lateral force in that direction to the West
face of the building.

We are mainly dealing with lateral forces due to a
basic wind speed of 90 mph.

I would appreciate any other opinions out there.

Thanks!
Brian