Balustrade Loading Clarification
Balustrade Loading Clarification
(OP)
I have searched for this in other posts but have not found anything specifically related, so my apologies if this has already been answered.
In the British and Australian codes there are generally 3 horizontally distributed line loadings at the top of balustrades: 0.75kN/m, 1.5kN/m, and 3.0kN/m. Prior to 2002, the Australian code didn't even have a 1.5kN/m loading condition and instead said every balustrade "shall be designed to resist a static load of 0.75kN/m..." and "On railings or balustrades which may be called upon to restrain crowds or people under panic conditions, a load of up to 3kN/m run may be exerted."
I am currently designing several balustrades where the loading requirements and type of occupancy are not clear, for example the external balcony of a private golf club or surf club, or the external balcony adjacent to a function room. Am I right in saying that loadings larger than 0.75kN/m are a result of people trying to get to the fire exit or exiting after an event and therefore being pushed against the balustrade by the crowd behind them? Therefore, if the balustrade is at the opposite end of the floor from the exit, there will not be people getting pushed into it in an emergency and it can be designed for 0.75kN/m?
Thanks
In the British and Australian codes there are generally 3 horizontally distributed line loadings at the top of balustrades: 0.75kN/m, 1.5kN/m, and 3.0kN/m. Prior to 2002, the Australian code didn't even have a 1.5kN/m loading condition and instead said every balustrade "shall be designed to resist a static load of 0.75kN/m..." and "On railings or balustrades which may be called upon to restrain crowds or people under panic conditions, a load of up to 3kN/m run may be exerted."
I am currently designing several balustrades where the loading requirements and type of occupancy are not clear, for example the external balcony of a private golf club or surf club, or the external balcony adjacent to a function room. Am I right in saying that loadings larger than 0.75kN/m are a result of people trying to get to the fire exit or exiting after an event and therefore being pushed against the balustrade by the crowd behind them? Therefore, if the balustrade is at the opposite end of the floor from the exit, there will not be people getting pushed into it in an emergency and it can be designed for 0.75kN/m?
Thanks






RE: Balustrade Loading Clarification
RE: Balustrade Loading Clarification
RE: Balustrade Loading Clarification
Lots of discussion about it, but there really isn't much "theoretical basis" for either value. Even the "failure mode" (how do determine of a design did not pass the 50 lbf/ft limit?) is not clear: The post deflects? How much yield is "good enough" and how far is "too far"? The post breaks the mounting? It deflects (yields) but holds the person back successfully?
Why 200 lbf? Has that value ever been justified, or is it just written down because somebody wrote it down? Treat it as a requrement.
RE: Balustrade Loading Clarification
In order to use any of the glass system it is crucial that I am able to justify using the max 0.75kN/m loading. The problem is that all the codes are ambiguous as to when higher loadings are required and do not provide clarity as to why they chose various values.
RE: Balustrade Loading Clarification
file:///C:/Users/Al/Downloads/BALUSTRADPOLICY110726.pdf
RE: Balustrade Loading Clarification
http://harkk.com.au/technical_information/load_cap...
RE: Balustrade Loading Clarification
Interestingly, ASCE-7 doesn't classify rail loadings by occupancy, except that the 50plf load is waived for industrial railings. Importantly, the commentary of ASCE-7 says that for special conditions where "extreme loads can be anticipated" from crowds "appropriate increases in loading shall be considered" but no guidance is given.
OSHA gives similar load requirements for rails to ASCE but uses fracture as the limit state.