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Memorandum
DATE November 9, 2017
TO Rocale Timmons
Seco Development
FROM Brian MacRae
PROJECT Southport Office
CPL PROJECT # S140194-11
SUBJECT Helipad Tower 2 Structure
ATTACHMENTS N/A
The area for the helipad is bounded by grids 11-12 and M.5-N.5 at the roof of tower 2. The structural system is
an 8” post-tensioned concrete slab with 16” post-tensioned wide-shallow beams in the E-W direction on
column lines. The slab and wide-shallow beams are supported by concrete columns which are supported by
pile caps at the foundation.
The helipad load-bearing area is 30’ by 30’ (900 SF) in size. The helipad has adequate capacity to meet at a
minimum the loading requirements of the 2015 IBC section 1607.6. The helipad is capable of accommodating
helicopters weighing up to 10,000 pounds.
The following loading combinations were used in the design of the helipad which meet and at times exceed
those of the 2015 IBC:
1. Dead load, D, plus the gross weight of the helicopter, Dh, plus snow load, S.
2. Dead load, D, plus two single concentrated impact loads, L, approximately 8 feet apart applied anywhere on
the landing area, having a magnitude of 0.75 times the gross weight of the helicopter. Both loads acting
together total one-and-one half times the gross weight of the helicopter.
3. Dead load, D, plus a uniform live load, L, of 100 psf.
Brian MacRae, P.E., S.E.
Project Manager