Abstract-Travel demand forecasting has become the target of increasing interest from both transport planners and engineers. It not only contributes primarily to sustainable city planning strategies, but is also an effective tool for quantifying transport impacts of new developments. This paper considers an alternative methodology to forecast residential trip demand using the UK TRICS database as the primary resource. The traditional category analysis approach seeks to classify historic travel surveys into categories determined by land use and other influential characteristics. By analysing trip rate variation for residential sites with different characteristics, this paper proposes a new classification system, which clearly represents differences in trip rates and optimises the value of the data. This new classification system (compared to that accomplished via TRICS groupings) simply partitions residential zones into those which are predominantly comprised of flats and houses. Travel models have been developed based on these two groups. These models allow forecasting of proposed residential sites. This paper confirms the importance of observed trip generation data, such as that provided by TRICS, as a valuable resource upon which travel forecasts can be based. In addition, this paper encourages the use of alternative methodologies including reclassification of sites and the adoption of regression techniques in order to improve validity of results.

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Urban streets are essential parts in cities and their development can enhance various aspects of economic life and social activities. Al-Najaf city is one of the Iraqi developing cities that has been suffering from traffic congestion at various sections of its street network. The reasons, locations and intensities of these congestions are important to be regularly diagnosed for two key reasons: first, in order to choose the right traffic engineering solutions and second to adequately prioritize the funding required for planning and implementing the traffic management programs for these congested sections. This paper attempts to evaluate the performance of the main urban streets located within the southern part of Al-Najaf city street network during evening peak hours. The methodology includes collecting field data and conducting traffic surveys such as traffic volume, travel time and free flow speed surveys. The evaluating approaches illustrated in the U.S Highway Capacity Manual are adopted as a tool for assessing the operational performance for the selected urban streets. The results reveal that there are several segments that operate at their capacity (LOS E) or even under congested flow condition (LOS F). The analysis also shows that whereas some segments are with good LOS using volume-capacity ratio (v/c) criterion, they are actually with low LOS based on field observations or when using travel time as a performance measure. This indicates the inadequacy of using v/c ratio alone in evaluating urban streets because part of the congestion at such streets is due to side friction operational delays rather than over traffic demand.

In the UK, TRICS is a national trip generation databases and system. It is recommended to be used in quantifying traffic impacts of new residential developments. Thus, any enhancement in its methodology will positively influence the transport assessment process. This paper has three objectives; first, to examine the possibility of proposing new statistically-proven grouping for the TRICS residential land use subcategories. The second objective is to use the proposed grouping to construct parsimonious models for home-based trip production that can aid in quantifying traffic impact assessment. The third objective is to examine the validity of the developed models against two of the most internationally recognised trip information systems; the UK TRICS and the US ITE Trip Generation Manual. The statistical analysis ended up with new more accurate grouping where based on it eight trip production model were built. The developed models were found to be practical and rigorous.