Development of Improved 4D CAD System for Horizontal Works in Civil Engineering Projects

Abstract

One of the purposes of using four-dimensional (4D) computer-aided design (CAD) system is to express numeric construction schedule data into a visual format. While existing 4D CAD systems are appropriate for building projects composed of vertical schedule progress and manufactured elements, the basic functions of those systems have limitations when directly applied to a civil engineering project, such as highway and railway facilities. Such projects include horizontal works, and their activities are carried out according to the elements of natural topography. This study attempts to develop a 4D CAD engine that supports analysis of the 4D objects for horizontal elements including a visual simulation of a cutting and filling status of an earthwork section in civil engineering projects. The system uses integrated information management techniques employing work breakdown structure for simulating 4D objects for each level. The developed engine includes new functions for visualizing work schedule and activity progress in highway and railway project with horizontal earthwork. Finally, to improve the practical applicability of a 4D CAD system, a new method for visualizing risk analysis data is suggested for future studies.