Lift Traffic Design: Calculation or Simulation?

Lift traffic design has become an integral part of tall building design. Typically, design calculations and/or simulations are iterated many times from early sketches until lifts are in use. Each iteration requires a significant effort from the parties involved in the design, namely, architects, consultants, developers and often also lift suppliers. Therefore, lift traffic design should be carried out with the most appropriate method to minimize the effort. Traffic calculation based on uppeak roundtrip is a well-known method and fast to execute but its validity is limited to collective control systems and simple building configurations. Lift traffic simulation, on the other hand, allows complex building models, traffic patterns and lift products such as destination control systems, double-deck lifts and multi-car lift systems. Simulations usually have long runtime and are susceptible to statistical inaccuracies possibly unknown to the designer. Hence, some combination of calculation and simulation is desirable to benefit from both methods, but they should provide consistent results. This paper re-establishes the link between traffic calculation and simulation with a collective control system, which sets the standard for using both methods consistently in lift traffic design with both collective and destination control systems.