WHO SHOULD APPROVE DETAILS?
Traditionally the structural engineer -
unequivocally the final decision maker - did indeed approve, approve with corrections, or
disapprove proposed details. Only the structural engineer has performed the analyses for
all loading effects and knows the effective area of steel required at all points, and thus
should provide interpretations of ACI Building Code requirements and be familiar with
recent research tests on the efficiency of such details as corners and joints.
Some code requirements are ambiguous, i.e., capable of several
good-faith interpretations by qualified structural engineers. A structural design drawing
should show all of the responsible structural design engineer's interpretations in detail,
and not rely for these on estimators, detailers, or reinforcing steel suppliers. The
structural engineer who omits these interpretations to save design time should at least
review all details and correct them as required for his approval before fabrication.
Under design-and-build or fast-track construction, the traditional
drawings review process is difficult to achieve. Construction begins with the foundation
design before the superstructure design is complete. The basic structural design is done
in the engineer's office; however, numerous incidental revisions often occur just prior to
construction.
Economics are achieved
by the owner who permits the responsible structural engineer to hire an inspector who is
fully familiar with the design engineer's details. A leisurely and complete review of shop
drawings is not possible, and the inspector should be given authority to make as-built
decisions in the field for the revisions being performed. Responsibility still lies with
the structural engineer, since his inspector may or may not need to be a registered
engineer, depending on the extent of revisions contemplated.
REFERENCES
1. ACI Committee 315, "Details and
Detailing of Concrete Reinforcement (ACI 315-80) (Revised 1986), "ACI Journal, Proceedings
V 83, No. 3, May-June 1986, pp. 485-524.
2. ACI Committee 315, ACI Detailing
Manual - 1980, SP-66, American Concrete Institute, Detroit, 1980, 212 pp.
3. ACI Committee 318, "Building Code
Requirements for Reinforced Concrete (ACI 318-83)," American Concrete Institute,
Detroit, 1983, 111 pp.
4. Uniform Building Code,
International Conference of Building Officials, Whittier, 1985, 817 pp.
5. Nilsson, Ingvar H. E., and Losberg,
Anders, "Reinforced Concrete Corners and Joints Subjected to Bending Moment," Proceedings,
ASCE, V. 102, ST6, June 1976, pp. 1229-1254.
