Joint Seals (compression seals): replacements & retrofits
Joint Seals (compression seals): replacements & retrofits
(OP)
On every detail (Wabo and various DOTs) the joint seal is always shown sitting on top of a neat little step: either a 1/2" strip of metal when the groove is armored or it is placed in the neat sawcut groove.
I wonder if it might be alright to omit the little step that is shown (i.e. place the seal between two flush, vertical surfaces)?
1) When I have seen these installed (without armoring) the groove depth was taken as a minimum and the operator of the saw was not doing precise work. I don't believe the seal was sitting on a neat little step as shown in the pictures.
2) I can only think of two reasons for the step as a restraint to prevent the seal from being shoved down too far during installation, or to keep the seal from being shoved down by say an accumulation of incompressible debris.
My thinking is that the contractor should be able to install the seal without shoving it down too far and that the typical silicone seal with a backer doesn't get shoved down by debris build up--so I am reasoning that it would be alright? I mean it takes a pry bar to get these things to move once installed?
It would greatly simplify construction to not provide the seat/step. Looks like it will be another "judgement" call from my desk...
I wonder if it might be alright to omit the little step that is shown (i.e. place the seal between two flush, vertical surfaces)?
1) When I have seen these installed (without armoring) the groove depth was taken as a minimum and the operator of the saw was not doing precise work. I don't believe the seal was sitting on a neat little step as shown in the pictures.
2) I can only think of two reasons for the step as a restraint to prevent the seal from being shoved down too far during installation, or to keep the seal from being shoved down by say an accumulation of incompressible debris.
My thinking is that the contractor should be able to install the seal without shoving it down too far and that the typical silicone seal with a backer doesn't get shoved down by debris build up--so I am reasoning that it would be alright? I mean it takes a pry bar to get these things to move once installed?
It would greatly simplify construction to not provide the seat/step. Looks like it will be another "judgement" call from my desk...





RE: Joint Seals (compression seals): replacements & retrofits
Plus, I think that little step provides some resistance years down the line when the adhesive wears out.
RE: Joint Seals (compression seals): replacements & retrofits
1) I am aware that the width requirement at time of installation is contingent on the bridge's temperature at that time.
2) I question whether the adhesive is necessary on these seals, its primary purpose being to lube the seal so that it can be placed.
I am currently dealing with existing bridges and a limited budget. Creating notches does not appear to be a cost effective solution in several locations.
RE: Joint Seals (compression seals): replacements & retrofits
BTW - NYSDOT armorless joints don't have the lip.
RE: Joint Seals (compression seals): replacements & retrofits
RE: Joint Seals (compression seals): replacements & retrofits
Some of the failures I am dealing with are caused by seals that were improperly sized or improperly installed.
If the failure in the picture was caused by the compression seal "walking" down to the bottom due to the cyclic back and forth deformation (and with a lack of step/seat to stop it), then my thinking could be wrong.
Do you know or have a guess why the seal in the photo failed?
RE: Joint Seals (compression seals): replacements & retrofits