INES—An Interactive Estimating System

A possible effective application of computers in construction is to use them for cost estimating. Despite their wide acceptance for cost accounting and other bookkeeping tasks, their use in estimating has lagged considerably. The emergence of powerful and low cost microcomputer systems has made it feasible for a broad range of contractors to own their own system. As a result, it is now very common for even the smallest contractors to own a system whose primary function is bookkeeping. Once bookkeeping tasks are automated, however, a natural progression is to also use them for cost estimating. It has therefore become necessary to develop an estimating system which takes advantage of the great potential of the microcomputer. This paper proposes and describes one such system.     

Efficient Repetitive Scheduling for High-Rise Construction

A new scheduling and cost optimization model for high-rise construction is presented in this paper. The model has been formulated with a unique representation of the activities that form the building’s structural core, which need to be dealt with carefully to avoid scheduling errors. In addition, the model has been formulated incorporating: (1) the logical relationships within each floor and among floors of varying sizes; (2) work continuity and crew synchronization; (3) optional estimates and seasonal productivity factors; (4) prespecified deadline, work interruptions, and resource constraints; and (5) a genetic algorithms-based cost optimization that determines the combination of construction methods, number of crews, and work interruptions that meet schedule constraints. A computer prototype was then developed to demonstrate the model’s usefulness on a case study high-rise project. The model is useful to both researchers and practitioners as it better suits the environment of high-rise construction, avoids scheduling errors, optimizes cost, and provides a legible presentation of resource assignments and progress data.     

Object-Oriented Scheduling for Repetitive Projects with Soft Logics

The application of network techniques of project scheduling to repetitive projects has been criticized for the inability of network techniques to help maintain work continuity. Moreover, current network techniques require a large number of activities to represent a repetitive project and presume that there is only one logical sequence. This makes schedules time consuming to develop as well as maintain. Further, the logic chosen by the planner might be far from the shortest possible duration. This paper, utilizing the soft logic sequencing principles developed by Fan et al., develops a system which provides an easy input module in addition to scheduling and work-continuity-maintenance modules. The system eases the network generation and update processes, which in turn provides the shortest possible duration logics and the start and finish dates required to maintain work continuity.     

Construction Management of a Small-Scale Accelerated Pavement Testing Facility

Research in accelerated pavement testing (APT) facilities has traditionally focused on the pavement performance such as rutting and fatigue cracking, but documentation on construction management and information of the actual pavement construction quality is limited. There are typically four critical factors that need to be considered to achieve the best possible outcome in construction: cost, schedule, construction process, and quality control, and management. With the objective of developing guidelines for planning and executing construction of a small-scale APT facility, this paper presents a case study documenting and evaluating the construction process and construction management efforts of two sensor-instrumented hot mix asphalt pavement test sections built in a small-scale APT facility. The focus of the experiment was to study bottom-up fatigue cracking of the flexible pavement structure. The presented information and lessons learned serve as a template and guide for agencies pursuing this type of research and pavement construction.     

Total Quality Management for Construction

Traditional approaches to quality control in the construction industry are inadequate and should be replaced with the Total Quality Control concept implemented through the Quality Control (Q.C.) Circle as developed in Japan and currently in wide use throughout the manufacturing industry. The term “total quality control” is defined, and four total quality control principles are set forth on the basis of this definition. The evolution of quality control is traced from the nineteenth century to today to explain the decline in quality standards and to illustrate the need for a new approach. Unique characteristics of the construction industry are described as they relate to the Q.C. circle concept. Implementation of this concept will result in higher quality, lower costs, and increased productivity in the construction industry.     

3D Scan Information Management System for Construction Management

This paper presents an internet-based three-dimensional (3D) scan information management system (3DSIMS) that can be used as an interface to input, display, and inspect design as-built construction information. This system is mainly developed using 3D scan data. The function of the 3DSIMS is to integrate the scan data collected before, during, and after a scan scheme that is designed to capture as-built 3D records. The information included in this system consists of a scan scheme, scanned point clouds, construction records, and postscan processed clouds for the display, search, and comparison of scans made each week during the construction of a campus building. This study represents a long-term effort that has rarely been done before. A web page is used to deliver and share scan information. The feasibility of this approach is explained by the examples of dimension-related checks through as-built data.     

QUALICON: Computer-Based System for Construction Quality Management

This paper describes a computer-based system for construction quality management. The system tasks are derived from the elements of ISO 9001 standard and designed to integrate with other computer-aided project management functions. They can assist management in (1) the definition of requirements/criteria for design, construction, and quality management; (2) the development of inspection and test plans; (3) the tracking of actual inspection/test results; (4) the verification of their conformance to defined criteria; (5) the documentation of past experience in the form of standard templates for assisting the tasks involved; and (6) the generation of reports. A model was defined for representing the information used in the system tasks. The central role of the inspection and test plan representation was exploited to associate to construction components and processes, relevant inspections/tests, requirements/criteria, actual results, and nonconformance analyses. Templates were devised to enable the reuse of predefined packages of information, which recur from project to project. The developed system will render the assisted quality management tasks more effective. Its use was tested on data from different construction domains.     

Integrated Electronic Commerce Model for the Construction Industry

The construction industry has been relentlessly searching for technology solutions to enhance its productivity and efficiency. This paper presents an investigation that was conducted to obtain an overview of the current situation of electronic commerce applications using Internet and web-based technologies for the construction industry. A conceptual model named Integrated Electronic Commerce Model for the construction industry is proposed in this paper. Based on this model, construction project scheduling process and its related business activities at the industry and enterprise levels are analyzed to compare the interaction and integration of construction processes, in the electronic commerce environment versus those in the traditional environment.     

SERC—A Model for Estimating Construction Inputs

One of the main problems in the process of design and management of construction projects is obtaining accurate information for preliminary estimates. This information is crucial for the development of integrated systems for construction management because of the relationship between construction input data and subjects such as estimating, cost control, scheduling, resource management, etc. Existing methods for estimating input that originated in industrial engineering are inadequate for the unique conditions of the construction industry. The model described in this paper applies statistical analysis of data from past projects, and enables the user to estimate the data needed for the construction of a new project. The model is based on the following components: Project items and their quantities; inputs needed to produce those items; and factors that affect inputs of a specific project. The model equation was calculated using multiple regression techniques. The paper concludes with a case study of a construction input configuration for a concrete structure.     

Float Consumption Impact on Cost and Schedule in the Construction Industry

Quantifying and minimizing the risks associated with delays in the construction industry are the main challenges for all parties involved. Float loss impact in noncritical activities is one of the complicated delays to assess on a project’s duration and cost. This is due to the fact that the deterministic critical path method cannot cope with such delays unless they exceed the total float values. Further, stochastic analysis, which is used in this research to assess the impact of such delays, is perceived by many planners to be complicated and time consuming. This paper presents a method to control the risks associated with float loss in construction projects. The method uses a recently developed multiple simulation analysis technique that combines the results of cost range estimates and stochastic scheduling, using Monte Carlo simulation. The proposed method quantifies the float loss impact on project duration and cost. Least-squares nonlinear regression is used to convert the stochastic results into a polynomial function that quantifies the float loss impact by relating directly the float loss value to project duration and cost at a specified confidence level.     

Development of a Quantification Proposal for Hidden Quality Costs: Applied to the Construction Sector

This study develops a quantification proposal for those quality costs that construction companies cannot estimate through objective criteria, known as hidden quality costs. This proposal will later be the object of validation through a real case: the quantification of the cost of loss of image that a construction company experiences as a consequence of a delay in the completion of a certain building. This proposal is of relevance to researchers in that it demonstrates how hidden cost quantification based on a fuzzy logic model can be developed and tested, and it provides the basis for future investigations. It is of relevance to professionals as it describes how fuzzy logic and quality costs can be used to effectively model industrial construction quality management.     

Software for Planning and Cost Control in Directional Drilling Projects

As the complexity and size of the projects undertaken by horizontal directional drilling (HDD) contractors rapidly increase, there is a growing need for the development of dedicated software designed to meet the industry’s special needs and requirements. This paper presents the results of a survey of the HDD industry’s software needs as well as a summary of commercially available software specifically designed for this industry. In addition, the development of two computerized applications tailored for the HDD industry are described. The first of these applications is an integrated data management system that combines asset management, cost control, estimating, and project tracking capabilities, enabling decision makers to closely monitor field performance in terms of expenditure and productivity. The second application is a simulation model developed for optimizing the utilization of drilling rigs and hydro-vacuum trucks on large-scale urban projects. Both applications are designed to improve the planning, estimating, and productivity of directional drilling projects, ultimately reducing the cost of expanding underground infrastructure networks.     

Construction Scheduling and Progress Control Using Geographical Information Systems

Traditional scheduling and progress control techniques such as bar charts and the critical path method (CPM) fail to provide information pertaining to the spatial aspects of a construction project. A system called PMS-GIS (Progress Monitoring System with Geographical Information Systems) was developed to represent construction progress not only in terms of a CPM schedule but also in terms of a graphical representation of the construction that is synchronized with the work schedule. In PMS-GIS, the architectural design is executed using a computer-aided drafting (CAD) program (AutoCAD), the work schedule is generated using a project management software (P3), the design and schedule information (including percent complete information) are plugged into a GIS package (ArcViewGIS), and for every update, the system produces a CPM-generated bar chart alongside a 3D rendering of the project marked for progress. The GIS-based system developed in this study helps to effectively communicate the schedule∕progress information to the parties involved in the project, because they will be able to see in detail the spatial aspects of the project alongside the schedule.     

Development of IFC Modeling Extension for Supporting Drawing Information Exchange in the Model-Based Construction Environment

The Industry Foundation Classes (IFC) has been known as a common product model that has interoperability between similar and dissimilar IT systems for the architecture, engineering, construction, and facility management (AEC/FM) industries covering all life cycle phases. Continuous efforts have been undertaken regarding the development of standardized specifications based on the IFC, a product model used in the AEC/FM industries. In accordance, the XM-4 project has been initiated by the Korea Chapter of the International Alliance for Interoperability (IAI) organizations to develop a two-dimensional (2D) extension model for IFC. The XM-4 project aims to add to the IFC2x platform the ability to exchange 2D computer-aided design data within representations of virtual building models, including annotations and styles mainly adapted from the ISO 10303. The focus of this research has been on developing a 2D extension model for the IFC as part of the IAI XM-4 project. This paper provides the scope and rationale of the model extension, major modeling concepts, defined high-level entities and row-level entities, and implementation issues to be considered.     

如何有效进行施工现场签证的控制

对当前施工现场价格签证现状进行了分析,提出了如何加强施工现场价格签证控制的组织、技术、经济、合同等措施。     

Application of Small Computers in Construction

The deliberations of the ASCE Task Committee on the Application of Small Computers in Construction are presented. The paper first identifies needs that are stimulating the application of small computers in construction, and then examines their present and potential utilization in several representative application areas. Applications include accounting and payroll, estimating, field office administration, contract language retrieval, electronic communications, scheduling, process simulation, graphical reporting, computer‐aided design, and process control. The role that ASCE might take in supporting the effective application of small computers in construction practice is considered. Possibilities include participation in the development of standards, education of practitioners, stimulation of innovative techniques, liaison with other organizations, input to computer manufacturers and software developers about specific needs and requirements in construction, studying the organizational and behavioral aspects of computers in construction, and input to ASCE awards committees about meritorious work in this area. It is concluded that an ongoing ASCE Construction Division committee is needed to monitor and influence the effective application of this rapidly evolving small computer technology in construction.     

Delay Analysis under Multiple Baseline Updates

Windows delay analysis has been recognized as one of the most credible techniques for analyzing construction delays. To overcome some of the drawbacks of windows delay analysis, this paper introduces improvements to a computerized schedule analysis model so that it will produce accurate and repeatable results. The model considers multiple baseline updates due to changes in the durations of the activities and the logical relationships among them, as well as the impact of resource overallocation. The model uses a daily window size in order to consider all fluctuations in the critical path(s) and uses a legible representation of progress information to accurately apportion delays and accelerations among project parties. A simple case study has been implemented to demonstrate the accuracy and usefulness of the proposed delay analysis model. This research is useful for both researchers and practitioners and allows detailed and repeatable analysis of the progress of a construction project in order to facilitate corrective actions and claim analysis.     

Using Weibull Analysis for Evaluation of Cost and Schedule Performance

Large amounts of money are lost each year in the construction industry because of poor schedule and cost control. Few contractors specify and follow systematic schedule monitoring practices. Traditionally, the earned value method (EVM) is used to control and monitor schedule performance using the schedule and cost performance indices which compare the budgeted cost of work performed to what was originally scheduled or what is actually expended. This paper presents a statistical approach, namely Weibull analysis, to evaluate stochastically the schedule performance of construction or design projects. The approach can be used in conjunction with the EVM to enhance the evaluation and control of schedule performance. Weibull analysis is a common method for failure analysis and reliability engineering used in a wide range of applications. In this paper, the applicability of Weibull analysis for evaluating and comparing the reliability of the schedule performance of multiple projects is presented. The various steps in the analysis are discussed along with an example in which two projects are analyzed and compared. The authors conclude that Weibull analysis has several advantages and provides a relatively robust and effective method for construction managers to better control and monitor their projects.