Strategies for serving peak elevator traffic

Suppose that in an office building of moderate height (5 to 20 floors) elev ator traffic during peak periods is predominantly between a lobby floor and Various upper floors. We compare the waiting plus riding time and the aver age number of passengers carried per trip for various strategies. In partic ular, if two (or more) elevators serve the same group of floors (a common s trategy), the waiting plus riding time would typically be (slightly) less i f one split the group into two parts and had each elevator serve separate p arts of this group. The latter strategy would have considerably fewer passe ngers per trip. It may also be advantageous to have a single elevator serve different floors on successive trips. Seldom would it be advantageous for an elevator to serve more than 2 or 3 floors on any trip. If elevator syste ms used more efficient strategies during peak periods, buildings would not need as many elevators. (C) 1998 Elsevier Science Ltd. All rights reserved.