The volume of highway traffic in the United States continues to increase. In the face of this there is a concomitant need to improve and repair transportation infrastructure. Construction frequently requires a reducti...The volume of highway traffic in the United States continues to increase. In the face of this there is a concomitant need to improve and repair transportation infrastructure. Construction frequently requires a reduction in capacity during construction activity; consequently road users as well as adjacent businesses must endure the delays and inconveniences associated with transportation construction. Recognizing the problems that construction can produce, state highway agencies （SHAs） have continually sought ways to minimize the negative impact from their construction operations. Incentive contracting has played an important role in this effort to improve project performance. The Florida Department of Transportation （FDOT） is one of the leading SHAs using such innovative contracting methods as Incentive/Disincentive （I/D）, A＋B （cost plus time bidding） combined with I/D, No Excuse Bonus, and Liquidated Savings. This paper analyzes the traffic impact on incentive project time performance using highway construction projects recently completed in Florida. Project data obtained from FDOT were evaluated using time performance indices. A survey of traffic impact on project work types was performed in Florida in order to evaluate the relationship between construction project types and road traffic influence during construction. Based on the survey results, the 38 most frequently used work types in Florida during the study period were categorized into three traffic impact levels： （1） high traffic impact, （2） medium traffic impact, and （3） low traffic impact. Statistical analysis was performed. The results show that there are significant differences on project time performance between low and high impact levels as well as low and medium impact levels.展开更多
The regular occurrence and the high costs of flooding to both road agencies and communities is a strong impetus to investigate the methodologies applied to evaluating flood immunity road projects. Very little literatu...The regular occurrence and the high costs of flooding to both road agencies and communities is a strong impetus to investigate the methodologies applied to evaluating flood immunity road projects. Very little literature exists on methods of evaluating the benefits of improving flood immunity through better road infrastructure. This paper attempts to address some of the numerous issues hindering the accurate evaluation of flood immunity road projects. The methodologies presented in this paper are designed to evaluate benefits that are not normally included or not fully considered in evaluations; such benefits include reduced flood related road accidents, costs of not travelling during the closure period and additional costs from unanticipated flood events. A key focus of the paper is the consideration of the evaluation of improved flood immunity from a network perspective rather than the typical approach of evaluating flood immunity projects in isolation to each other. The application of the proposed methodologies is demonstrated with a hypothetical example of a typical rural network subjected to regular flooding. The results of the analysis, conducted using the proposed methodologies, reveals that the currently applied methodologies account for less than half the likely value of benefits of a package of projects that will prevent the complete isolation of communities during serious flood events.展开更多
There is a variety of PDSs （project delivery systems） in today＇s construction industry. This leads to confusion when it comes to selecting the most suitable PDS for a specific project. The wrong selection decision ...There is a variety of PDSs （project delivery systems） in today＇s construction industry. This leads to confusion when it comes to selecting the most suitable PDS for a specific project. The wrong selection decision might lead eventually to reduced profit margins or perhaps financial losses to PSFs （professional service firms）. This research proposes a conceptual framework that helps PSFs in the selection of one or more suitable PDSs for their construction operations. The framework uses SWOT （strengths, weaknesses, opportunities and threats） analysis as a tool for assessing each PDS considered in this research. The PDSs included in the framework are design-bid-build, design-build, construction management agency, public-private partnerships and integrated project delivery. The main aim of this research framework is to enhance decision-making efficiency in PDS selection for PSF operations.展开更多
文摘The volume of highway traffic in the United States continues to increase. In the face of this there is a concomitant need to improve and repair transportation infrastructure. Construction frequently requires a reduction in capacity during construction activity; consequently road users as well as adjacent businesses must endure the delays and inconveniences associated with transportation construction. Recognizing the problems that construction can produce, state highway agencies （SHAs） have continually sought ways to minimize the negative impact from their construction operations. Incentive contracting has played an important role in this effort to improve project performance. The Florida Department of Transportation （FDOT） is one of the leading SHAs using such innovative contracting methods as Incentive/Disincentive （I/D）, A＋B （cost plus time bidding） combined with I/D, No Excuse Bonus, and Liquidated Savings. This paper analyzes the traffic impact on incentive project time performance using highway construction projects recently completed in Florida. Project data obtained from FDOT were evaluated using time performance indices. A survey of traffic impact on project work types was performed in Florida in order to evaluate the relationship between construction project types and road traffic influence during construction. Based on the survey results, the 38 most frequently used work types in Florida during the study period were categorized into three traffic impact levels： （1） high traffic impact, （2） medium traffic impact, and （3） low traffic impact. Statistical analysis was performed. The results show that there are significant differences on project time performance between low and high impact levels as well as low and medium impact levels.
文摘The regular occurrence and the high costs of flooding to both road agencies and communities is a strong impetus to investigate the methodologies applied to evaluating flood immunity road projects. Very little literature exists on methods of evaluating the benefits of improving flood immunity through better road infrastructure. This paper attempts to address some of the numerous issues hindering the accurate evaluation of flood immunity road projects. The methodologies presented in this paper are designed to evaluate benefits that are not normally included or not fully considered in evaluations; such benefits include reduced flood related road accidents, costs of not travelling during the closure period and additional costs from unanticipated flood events. A key focus of the paper is the consideration of the evaluation of improved flood immunity from a network perspective rather than the typical approach of evaluating flood immunity projects in isolation to each other. The application of the proposed methodologies is demonstrated with a hypothetical example of a typical rural network subjected to regular flooding. The results of the analysis, conducted using the proposed methodologies, reveals that the currently applied methodologies account for less than half the likely value of benefits of a package of projects that will prevent the complete isolation of communities during serious flood events.
文摘There is a variety of PDSs （project delivery systems） in today＇s construction industry. This leads to confusion when it comes to selecting the most suitable PDS for a specific project. The wrong selection decision might lead eventually to reduced profit margins or perhaps financial losses to PSFs （professional service firms）. This research proposes a conceptual framework that helps PSFs in the selection of one or more suitable PDSs for their construction operations. The framework uses SWOT （strengths, weaknesses, opportunities and threats） analysis as a tool for assessing each PDS considered in this research. The PDSs included in the framework are design-bid-build, design-build, construction management agency, public-private partnerships and integrated project delivery. The main aim of this research framework is to enhance decision-making efficiency in PDS selection for PSF operations.
