Monday, January 7, 2008

Re: Glass guardrail support

I don't know if it is current but ASTM E985-96 "Permanent Metal Railing Systems and Rails for Buildings" has reference to static loads and deflections during testing iaw E894 and E935.  Max. allowable deflection:
  For horizontal load at mid-span:  h/24 + L/96
  For horizontal load at top of post (I know, all glass, no posts):  h/12
  For vertical load at mid span:  L/96
 
Perhaps this criteria would also apply to your glass system.
 
Last time I checked an all glass guard system, the glass was grouted into a deep shoe at the base and the Aluminum handrail was used to help distribute the horizontal forces along the top of the glass.  I was there during construction and the glass panels stiffened up a lot when the hand rail was attached. 
 
Paul.
Phoenix, AZ
 
 
-----Original Message-----
From: Jeff Smith [mailto: jeffsmith7@comcast.net]
Sent: Friday, January 04, 2008 4:47 PM
To: seaint@seaint.org
Subject: RE: Glass guardrail support

Do hand rails, glass or otherwise, have deflection requirements? I have never found it, but I prefer something very solid.
 
Jeff 
 

From: Harold Sprague [mailto:spraguehope@hotmail.com]
Sent: Friday, January 04, 2008 2:40 PM
To: seaint@seaint.org
Subject: RE: Glass guardrail support

 
Back in years gone by we simply required the guard rails to be tested after they were installed.  I was amazed how much glass could bend, but they performed well, and I slept well. 

Regards,
Harold Sprague