My architect is questioning my ability to obtain a light weight block with a compressive strength of 3500 psi. Can you clarify?
First you need to make sure you understand what is being required. We are assuming we are discussing a individual block with a net area compressive strength of 3500 psi. If that is the case then there is no problem. Lightweight high strength block in that range are manufactured every day.
On the other hand, if an f'm=3500psi is what the specifier has in mind the answer would be no. Not available in any weight block, light or not. And not recommended if it was. f'm=3500 psi is literaly "off the chart"! That is the chart in Table 2 of TMS 602-16 which is the current masonry code in the FBC 6th Ed.
Jerry Painter, FASTM
Don Beers, PE, GC
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