Tuesday, January 31, 2012

Gathering Missing Info on Blast Projects Saves Time.

Many blast project specs do not provide enough information to come up with the equivalent 3-second blast design pressure from ASTM F2248. Glazing contractors can save time by requesting the following information in advance.
 
  • Explosive Weight - (Typically for most projects explosive weight II)
  • Standoff Distance - (For most projects it is the Conventional Construction Stand Off = 82 ft)
  • Level of Protection - (Typically Low Level of Protection)
 
This criteria is usually determined during the design phase of a project by the using agency or the design team.
  
For more helpful information on blast projects see JEI Structural Engineering WINGARD, Windas, Window Blast, Blast Mitigation Design

Thursday, January 26, 2012

lateral-torsional buckling on storefronts

Regulations have changed so there is a need to design for the lateral-torsional buckling on storefronts now.   

Section 8.4.B.3.a of the ‘Aluminum Windos and Doors, and Glazing’ specifications states the following:



The AAMA standard dealing with storefront design is ‘AAMA SFM-1-87:  Aluminum Storefront and Entrance Manual’.

Engineering Section 6.0 (shown below) directs us to the current Aluminum Association’s Aluminum Design Manual (2010):
The Aluminum Design Manual, section F.2 (shown below), indicates that when framing members are subject to lateral buckling, the nominal flexural strength must consider the un-braced length of the framing in question:

We want you to have this information to give you a better understanding of why we are designing open shaped verticals mullions to prevent lateral-torsional buckling.   This increases the stablity and life of the storefront wall installation providing a higher level of client statisfaction to the end user.


Tuesday, January 3, 2012

Glass Roads - the prototype

Solar powered glass highways on zooming toward you.   How will it impact the glazing industry?



http://www.jeistructural.com/blog/?p=300