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Brick veneer seperation

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Wesley Eldred wrote:

>>I apologize for taking advantage of this list as a non-engineer.  I
stumbled across reference to this forum when researching our building
problem on the web and your collective experience could help with its
resolution.

An addition to our University Library was constructed in 1981.  Post
tensioned 9" floor slabs are supported by reinforced concrete columns.
Reinforced concrete beams, buttresses and shear walls were designed to
provide lateral reinforcement for our seismic zone (2).  Floors are
structurally adequate _ designed for 150 lb/sf live load _ although they
flex somewhat under the load of collections.  There have been no signs
of structural settling.  Structure is four story with the main entrance
at level 2 and progressive overhangs on two sides for levels three, four
and the roof.  Cracks have been evident for years in the facing brick
where the lintels at the overhangs tie into vertical walls.  During this
past year new cracks have appeared and the old cracks have opened
considerably.  Some portions of the brick appear in danger of collapse
as they seem to be separating from the support behind.  Cracks appear
mostly near corners and are mostly vertical or diagonal.  Support angles
were provided at each floor level (12') and backer rod and resilient
filler were used to create horizontal expansion joints just below the
support angles.  In several places cracks cross the horizontal expansion
joints _ which puzzles me.  Vertical expansion joints are generally
spaced at 27' following the building's structural grid.  Specifications
called for ties to the structure spaced at 20" horizontally and 16"
vertically.  In some areas bricks are tied to concrete and in others to
sheathing on metal studs.

A structural engineer speculated about the flexibility that might be
inherent in this type of building while recommending further analysis of
the problem and hiring of a firm to develop repair plans.  At this point
no bricks have been removed for closer inspection of problem areas.  My
real concern is that we should understand as much as possible about why
this is happening so we can perform repairs that will stand the test of
time.

If you have any thoughts that would be helpful, I would be most
grateful.  If the question is better posed to another list and you can
steer me towards it, I would appreciate that also.

Thank you,

Wesley
Facility Mgr, UVM Libraries<<

Wesley,

Please don't take this comment wrong, but what you have asked is like asking 
a cardiologist that doesn't know you and has never examined you what is wrong 
with your heart over the phone.

There can be many things causing the problems that you describe and the only 
way to find out is to retain a competent, experienced structural engineer or 
structural engineering team to inspect, investigate, test, analyze, examine 
and do whatever else is necessary to determine the cause and to come up with 
remedial measures.  Just as you would not solicit bids from a cardiologist, 
you should not solicit bids for structural engineering services.  No one can 
predict the amount of time and effort that would go into performing an 
investigation, so the work would probably be performed on a time and 
reimbursable expenses basis.  While this would not be inexpensive, it would 
be cheap in comparison if some part of the library did fail and injure or 
kill someone.

A. Roger Turk, P.E.(Structural)
Tucson, Arizona