The live loads specified in Section 13-52-090 shall be assumed to include adequate allowance for ordinary impact conditions. Provision shall be made in the structural design for uses and loads that involve unusual vibration and impact forces.
Elevators. All elevator loads shall be increased by 100 percent for impact, and the structural supports shall be designed within the limits of deflection prescribed by American National Standard Safety Code for Elevators and Escalators, A.N.S.I./A.S.M.E. A17.1-1981, and American National Standard Practice for the Inspection of Elevators, Escalators, and Moving Walks (Inspector’s Manual), A.N.S.I. A17.2-1979.
Machinery. For the purpose of design, the weight of machinery and moving loads shall be increased as follows to allow for impact: (1) elevator machinery, 100 percent; (2) light machinery, shaft- or motor-driven, 20 percent; (3) reciprocating machinery or power-driven units, 50 percent; (4) hangers for floors or balconies, 33 percent. All percentages shall be increased if so recommended by the manufacturer.
Craneways. All craneways except those using only manually powered cranes shall have their design loads increased for impact as follows: (1) a vertical force equal to 25 percent of the maximum wheel load; (2) a lateral force equal to 20 percent of the weight of the trolley and lifted load only, applied one-half at the top of each rail; and (3) a longitudinal force of ten percent of the maximum wheel loads of the crane applied at the top of the rail.
Exception. Reductions in these loads may be permitted if substantiating technical data acceptable to the building commissioner is provided.
(Prior code § 68-2.10; Added Coun. J. 11-29-89, p. 8387; Amend Coun. J. 9-13-89, p. 4604; Amend Coun. J. 3-5-03, p. 104990, § 20; Amend Coun. J. 11-13-07, p. 14999, Art. II, § 1)