||"Construction processes range from the relatively simple to the most complex.In the construction industry, complex decisions yielding maximum benefit arean essential component of process design and planning. Simulation modelingand Virtual reality are thus being increasingly used to help decision-makersmake economically optimal decisions.Although many advances have been recently made in the area of constructionprocess modeling (e.g. STROBOSCOPE), the Visualization/Animation aspect hasmainly focused on the finished product (3D CAD) or on the product as itevolves through construction (4D CAD). Very little attention has been givento visualizing the construction process that leads to the end product,which includes temporary structures and materials, equipment and labor asthey create the product. The process visualization/animation tools currentlyavailable commercially are restricted to two dimensions (e.g., ProofAnimation), inherently lacking in the real world 3D capabilities that areindispensable for the realistic visualization of many constructionoperations.This paper describes on-going research at Virginia Tech that focuses on thedevelopment of a general-purpose, 3D and trace-drivenvisualization/animation system. This system enables visualization of boththe construction process and the resulting product in 3D. The tool enablesthe easy creation of realistic 3D animations using CAD models from supporteddata file formats. The core of the work is a simple yet extremely robust setof animation commands, the capability to process sequences of thesecommands, and the ability to navigate effortlessly in 3-D space. The inputto the program is an ASCII text file consisting of sequential commandstatements. This file can be generated automatically by a variety ofsimulation software tools such as STROBOSCOPE, which is currently being usedto test the system.Due to the flexibility of the command set and the independence of the toolfrom any particular simulation modeling software, the system has numerouspotential applications in fields other than construction, such as in themanufacturing and service industries. Construction simulation modeldevelopers will find this tool useful for debugging their model andverifying that analytical models indeed behave correctly."