Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

Register Log in
  • Congratulations cowski on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

FRP over an existing plastered wall?

Status
Not open for further replies.
Backcheckrage

Backcheckrage

Structural
Joined
Sep 23, 2012
Messages
84
Location
NZ
Hello community,

I have an existing 1940's concrete frame system with infill brick for the entire elevation(two leaf with a 25mm air gap in between). I am considering installing FRP at the base floor to halt potential soft-story effects when the infill fails . The issue is that there is an existing cement plaster render on both sides of the infilled frame. My question is what do you think of installing FRP over the plaster rather than chipping out all the plaster where this will go? I think applyying FRP to the existing brick is always ideal but in terms of shear transfer, im sure i can transfer shear forces from the conc frame to the FRP, the plaster is only bracing the FRP. Thoughts?
 
Sort by date Sort by votes
How would the shear forces from the concrete frame get to the FRP if you don't attach it directly to the frame. Without designing the plaster to transfer the loads I would shy away from that.
 
Upvote 0 Downvote
You would be depending on two bonded interfaces rather than one. FRP to plaster, and plaster to brick. Perhaps you need to do some testing of the existing plaster to brick bond to assure yourself that it is strong enough. Seismic retrofitting always depends as much on judgment as on analysis, but I would want to be satisfied that the plaster is sound and well adhered.
 
Upvote 0 Downvote
I appreciate the feedback. You are all echo-ing my thoughts. Cheers.
I'm just going to have blow out the plaster and install FRP, I can sleep better that way.
 
Upvote 0 Downvote
I appreciate the feedback. You are all echo-ing my thoughts. Cheers.
I'm just going to have blow out the plaster and install FRP, I can sleep better that way.
 
Upvote 0 Downvote
Have you considered blowing out the plaster and bricks, and infilling with reinforced concrete? In my area, FRP is an expensive alternative.
 
Upvote 0 Downvote
wannabeSE,
Actually my situation is a bit unique in that my client's property is half of an existing structure. If I stiffen up the elevation in the way you are talking about, then i am introducing eccentricity in a big way because i have ability to equally stiffen up the elevation on the neighbor's side of the building. I am only trying to introduce ductility into the existing system rather than stiffen it up and have it attract more load (it's founded on a rock, so ground has stiff period already).
 
Upvote 0 Downvote
oops, missed a word: ...I don't have the bility to equally stiffen...
 
Upvote 0 Downvote
Did you check your plaster for asbestos? May not be an issue... it was often used as a binder for plaster at that time period.

Dik
 
Upvote 0 Downvote
Status
Not open for further replies.

Similar threads

destory
  • Question Question
Modifying an Existing ICF Wall
Replies
2
Views
2K
JAE
JAE
E
  • Locked
  • Question Question
Existing Suspended Slab Rectifications
Replies
0
Views
1K
engoaus
E
J
  • Locked
  • Question Question
Retaining wall replacement (TIMBER SHEETPILLING)
Replies
5
Views
4K
phamENG
phamENG
David Deck Guy
  • Locked
  • Question Question
FRP, Roof Leaking, and Delamination
Replies
3
Views
1K
HTURKAK
HTURKAK
ikka
  • Locked
  • Question Question
Retrofitting RCC Wall with a hole
Replies
2
Views
3K
jayrod12
jayrod12

Part and Inventory Search

Sponsor

Back
Top