Neoprene

[1prsplmps1]

Greetings: Does anyone know where to find the coefficient of static friction of neoprene (plain 50 durometer) on steel and neoprene on concrete?

Thanks in advance..

 

[dbuzz]

Suggest you discuss with a bearing supplier.

 

[JStephen]

It would be fairly simple to test if you have sample material available. Set a piece of one material on the other, tilt until it slides, and measure the angle. Summing the forces on the sliding piece will let you calculate coefficient of friction from the angle only.

I can see there being some variation in the values under heavy loads.

 

[1prsplmps1]

dbuzz: Before I wrote this post I did a little research on the issue and had no luck.
JStephen: Is a good idea but I need to have something from a manufacturer/distributor on record.

Thanks for your prompt responses!

 

[blake989]

If your talking about a bearing pad, it is a function of the compressive stress on the pad. I have some graphs of the the relationship for both steel and concrete to chloroprene(neoprene). The graphs I have are from PCI Tech Report #4 (20 years old). If you have a fax # I'll send them to for your entertainment.

 

[1prsplmps1]

blake989: That is a good beginning, the fax # is 704-358-8342. ATT. to Jamie/Pedro, thanks!

 

[youngstructural]

I would be a little concerned with the shrinkage of concrete, as this might reduce the effective coefficient of friction over time. Of course, this depends on the application, etc. as to whether or not it would be of concern.

Also, our office also has a copy of some old technical reports on neoprene, but these probably will not be reflective of current products. Let me know if you would like copies faxed/scanned.

 

[1prsplmps1]

blake989: Just to let you know that I've received your fax, thanks! Excellent info!!
youngstructural: It does not hurt to have those too.. Send them to the fax shown above your post, thanks in advance!

 

[crossframe]

I once heard a comment at a steel bridge conference that the coefficient of friction is about 0.20, both for steel and for concrete. And as blake989 pointed out, the lateral capacity is a function of the compressive force. I've always thought this was somehow related to the AASHTO requirement limiting the lateral load to one-fifth of the dead load or provide a positive connection.