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The objective of this study was to reveal the trend in highway construction costs following Hurricanes Katrina and Rita in Louisiana. The means of measuring highway construction cost was the Louisiana Highway Construction Index, an index made up of the cost of labor, equipment, and six major materials used in highway construction. Data from projects let by the Louisiana Department of Transportation and Development from the second quarter of 2003 to the second quarter of 2007 were used to track the change in construction costs. Index values from hurricane-impacted areas (GO Zones) were compared with those in Non-GO Zones. The indices revealed that two quarters after Hurricanes Katrina and Rita, the highway construction cost jumped about 20% statewide and 51% in GO Zone. Two years after the hurricanes, the cost has stabilized to around 30% increase over the pre-Katrina and Rita period. This study provides valuable information for the state agency to estimate cost escalation in ongoing projects and to estimate future disaster response to highway construction costs. DOI: 10.1061/(ASCE)CO.1943-7862.0000015 CE Database subject headings: Highway and road construction; Construction costs; Hurricanes; Louisiana.

The objective of this research was to develop a procedure that estimates the escalation of highway construction costs over time. An artificial neural network model was developed which relates overall highway construction costs, described in terms of a highway construction cost index, to the cost of construction material, labor, and equipment, the characteristics of the contract and the contracting environment prevailing at the time the contract was let. Results demonstrate that the model is able to replicate past highway construction cost trends in Louisiana with reasonable accuracy. Future construction input costs are estimated from commercially available forecasts of indicator variables closely associated with the price of construction labor, construction equipment, and a representative set of highway construction materials. Future contract characteristics and the contracting environment that is likely to exist in the future are estimated from past trends or stipulated to be consistent with policy decisions in the future. The predictions produced by the model estimate that highway construction costs in Louisiana will double between 1998 and 2015. CE Database subject headings: Construction costs; Bids; Cost estimates; Neural networks; Forecasting; Predictions; Highway construction.

A common travel analysis technique is to ascribe capacities to links in a planning network based on functional classification or facility type, under which a four-lane divided arterial, for example, would be assigned the same capacity everywhere, irrespective of the surrounding land use, the presence of traffic signals, and whether turning lanes are provided or not. While this practice has been used for many years and is typically adequate for the analysis of large road networks, there are penalties (in terms of lost accuracy) that accompany its use. The objective of this research was to evaluate different techniques to determine what information was necessary to reasonably estimate link capacity while decreasing the time, effort, and cost of data collection. It was found that assigning capacities on a link-specific basis produced significant differences when compared to the practice of assigning average capacities, suggesting that travel demand modeling could be improved by using link-by-link estimates of capacity. The results of this study also supported the concept that improvements gained by using all Highway Capacity Manual adjustment factors were marginal compared to the improvement achieved by including only the g/C ratio and number of lanes; suggesting further that ignoring other factors like lane widths, heavy vehicles, turning movements, etc. will still result in reasonably accurate estimates of volume, travel time, and travel speed. CE Database subject headings: Urban planning; Network analysis; Traffic capacity; Traffic volume; Travel demand; Transportation planning.

Full and partial transfer results of trip-production models among intercity, intracity, and intraregional locations are reported in this paper. Nineteen models were transferred 208 times among the locations. The variety of transfer conditions and number of transfers permitted inferences to be drawn on the conditions influencing transferability. It was observed that the quality of local data seriously affects the ability to discern transferability, and may account for the variable results observed in the literature. It was also observed that model quality and income affect transferability. For all transfers conducted in this study, the transferred models explained an average of 57% of the variation in trip-making behavior explained by locally estimated models. When locally estimated constants were used to replace transferred constants in the model, the transfer models explained, on average, 87% of the variation in trip-making behavior explained by locally estimated models. It was concluded that the adjustment of transfer-model parameters with local information (partial transfer) has the potential to improve transferability to such an extent that the need to predict transferability becomes redundant.