Title:
Concrete Q&A: Modification of Existing Structure with Change in Loads
Author(s):
Publication:
Concrete International
Volume:
39
Issue:
9
Appears on pages(s):
88
Keywords:
DOI:
10.14359/51701021
Date:
9/1/2017
Abstract:
The Q&A in the May 2017 CI featured an
interesting question about existing structures. The
answer is related to one of my current projects. I
am the licensed design professional (LDP) responsible for the
structural design of a modification of a hotel building at a ski
resort. The owner wants to create an exterior rooftop terrace
(bar) on the top floor of the building by removing a portion of
the existing roof and façade. The original floor was designed
for hotel occupancy. However, the new terrace area would be
exposed to both snow loads and a higher occupancy floor
load. The existing structure is reinforced concrete beam
and slab construction from the early 1980s. What are the
appropriate code provisions for the evaluation of the existing
structure? How should I deal with the snow load (including
drifting snow) and increased live load on the new terrace area
(again, the structure was designed for residential floor loads)?
Related References:
1. ACI Committee 562, “Code Requirements for Assessment, Repair, and Rehabilitation of Existing Concrete Structures (ACI 562-16) and Commentary,” American Concrete Institute, Farmington Hills, MI, 2016, 86 pp.
2. “IEBC 2015: International Existing Building Code,” International Code Council, Country Club Hills, IL, 2015, 304 pp.
3. “IBC 2015: International Building Code,” International Code Council, Country Club Hills, IL, 2015, 700 pp.
4. ACI Committee 318, “Building Code Requirements for Structural Concrete (ACI 318-14) and Commentary (ACI 318R-14),” American Concrete Institute, Farmington Hills, MI, 2014, 519 pp.