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Time-lapse recording allows lengthy construction processes to be recorded and played back in a much shorter time for subsequent analysis. Over the past decade, time-lapse video cassette recorders (TL VCRs) have replaced time-lapse film movies for detailed productivity analysis and improvement in construction operations. This paper describes some of the technical features and options of time-lapse video recording equipment. The paper presents a valuable new application for time-lapse video in monitoring construction field operations. Rather than concentrating on individual workers or crews, time-lapse video can also be used to document and observe construction projects in their entirety. This innovative application has been extremely beneficial in historical documentation of project progress, operations analysis and improvement, public relations, fund raising, and dispute resolution. This paper presents lessons learned from several years of experimentation and experience with time-lapse video and two cases where time-lapse video recordings have been used to resolve claims and disputes on construction projects.

This paper aims to present an easy, quick, and accurate way of implementing value engineering (VE) studies by introducing an integrated computerized system for the VE technique and life-cycle cost as a checkout system. The VE computer program was designed using a database computer program, FoxPro Window. The computerized version of the VE study consists of several interactive panels, representing the systematic approach (job plan) of a VE study, through which all the information and data of the VE study will be input. The program will help the user to come up with the best selected idea, based on certain calculations that will be done automatically by the VE program. Moreover, the VE case studies that will be investigated by the program will be stored, and thus the program will also serve as a data bank for these case studies as references for future studies. The objective of this paper is not to create a smart VE system, but it can be considered a major step toward this objective.

This paper discusses the development of an animation tool for the activity-based construction (ABC) modeling and simulation system. The tool uses an activity-based network diagram, i.e., ABC simulation model, as the animation background image, and uses precreated two-dimensional (2D) iconic images for simulation entities (e.g., resources). The animation process displays the queuing status and dynamic movements of 2D iconic images on the background. It also distinguishes active and idle states of resources and activities. Dynamic reports are available for selected activities with graphs including the production rate and utilization of involved resources. From visualizing the change of status of a simulation process and dynamic interaction between simulation entities in the process, the user can better understand the dynamic nature of the construction process. Animation provides an avenue to demonstrate how dynamic operations are simulated. It also provides an effective tool for the user to verify a simulation model and to validate the obtained simulation results. Compared to other systems, the ABC animation does not require any extra effort in addition to the ABC simulation model constructed for simulation purposes. Therefore, the presented technology greatly reduces the time and cost for achieving animation. A variety of useful information can be observed through animation, and is illustrated using two construction examples. DOI: 10.1061/(ASCE)0887-3801 (2002) 16:3(157) CE Database keywords: Construction management; Simulation models; Imaging techniques.

Computer-integrated construction (CIC) and concurrent engineering for architecture, engineering, and construction (AEC) require data standards or common information models through which computer systems can exchange project information. High-level conceptual core models are required as unifying references for the more detailed, application-specific models used for the actual information exchange. A variety of core models have been developed in the area of AEC process information. This paper introduces several such models from a variety of projects. It discusses general modeling mechanisms and looks at several issues relating specifically to process modeling for AEC, comparing the approaches of the various core models described, and providing some recommendations. The overall objective is the eventual emergence of generally accepted standards in this area.

The variability of the random buckling loads of beams and plates with stochastically varying material and geometric properties is studied in this paper using the concept of the variability response function. The elastic modulus, moment of inertia, and thickness are assumed to be described by homogeneous stochastic fields. The variance of the buckling load is expressed as the integral of the auto- and cross-spectral density functions characterizing the stochastic fields multiplied by the deterministic variability response functions. Using this expression spectral-distribution-free upper bounds of the buckling load variability are established. Further, the buckling load variability for prescribed forms of the spectral density functions is calculated. Using a local average approach, the commercial finite-element package ABAQUS is incorporated into the analysis of these random buckling loads. The technique is applied to study variability of the critical buckling load of a stiffened steel plate used in experiments to model a barge deck.