Neoprene Pad Bearing/Compressive Strength 6

[struggle67]

Hi

I noticed that in precast construction, neoprene bearing pads are quite commonly used but I couldn't seem to find any info on its bearing/compressive strength (only hardness is specified). What is the conservative compressive strength value that I should assume or is there any correlation with the hardness value?

Thanks

 

[Ussuri]

Member Slideruleera has posted a collection of historical documents. One is an old DuPont document called the Engineering Properties of Neoprene Bridge Bearings (see link below).

http://www.slideruleera.net/miscellaneous.html

http://www.slideruleera.net/

 

[bridgebuster]

The NYSDOT Bridge Manual has design examples for various types of elastomeric bearings

Link

They also have MathCAD sheets

Link

NYSDOT Bearing Standard Sheets are here

Link

The old DuPont Manual is still OK to a point - I used it decades ago when it was the only design procedure available - but you should use a more up to date reference. Other DOT's and NSBA also have design examples.

 

[JedClampett]

Here's an oldie but goodie from the 2nd Edition PCA Design Handbook.

 

[BAretired]

It may vary among manufacturers, but 2,000 psi seems to be the maximum bearing stress on one product I checked with Google.

BA

 

[BAretired]

I don't know if any great harm would come to increasing the pressure above 2,000 psi. The value of E seems to be a straight line between 0 and 2,000 psi, but that may be an approximation. Increasing the pressure to, say 4,000 psi would cause a deflection greater than 1/2 the thickness of the pad and (I'm guessing) could cause rupture in the pad material. That is a question one could ask the supplier.

BA