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Abstract: This article proposes a model for analysing the modal choice of travellers making inter-urban journeys. Discrete choice models with systematic and random tastes variation were applied to find the most relevant variables for encouraging the use of public transport by bus rather than private car. This research follows on from the results of previous user satisfaction studies on inter-urban bus services in the province of Burgos (Spain). Willingness to pay is also estimated for time savings or other improvements in the bus service. The results indicate that, in general, improvements in the journey time or the number of daily journeys are valued less by inter-urban bus users than they are by car or railway users. The type of bus and its characteristics are evaluated as a function of the distance travelled and result in very small values for this variable. Contrary to what is often reported in satisfaction surveys, the journey cost is found to be relevant when choosing which mode of transport to use, but the most important variable is journey time. Little value is placed on the features of the bus, except on long distance journeys. Finally, a methodology differentiating four hierarchical groups is presented for comparing the results of the relevant variables in demand and satisfaction models. Some only improve perception rather than encourage new users, while others increase take-up but do not improve the image of the service. [Copyright &y& Elsevier]

• Pavement deterioration models are important to effectively manage a road system. • Two roughness evolution models for semi-rigid pavements were developed. • Materials in the base and subbase layers and their thicknesses affect roughness. • Models use the segment age along with heavy vehicle traffic and total traffic volumes. • Introducing bituminous material of the surface layer improves the model accuracy. Pavement deterioration models are a vital feature in any pavement management system since they are capable of predicting the evolution of pavement characteristics. Pavement roughness is measured by most of the highway administrations due to its relation to comfort and safety, generally by means of the International Roughness Index (IRI). The Regional Government of Biscay (Spain) has collected IRI values since 2000 on its road network. Although many models have been developed for flexible pavements, very few have been proposed for semi-rigid pavements. The paper aims to develop IRI prediction models for semi-rigid pavements in single-carriageway roads. Considering the high quantity of available information in the database, deterministic models were selected. Due to the importance of the pavement structure in IRI evolution observed in flexible models, only segments with completely known pavement details were employed, i.e., a section where the complete structure is known: materials and thickness of existing layers above the subgrade. The pavement age, as precise as practical, and the accumulated total traffic and heavy traffic through the section were identified as roughness accelerating factors. Conversely, the materials used in base and subbase layers, their thickness, and the total thickness of bituminous layers were observed as degradation reducing factors. Possible treated base and subbase materials included in the model were soil–cement, gravel-cement, and gravel and slag. The obtained model achieved a determination coefficient (R2) of 0.569. Additionally, the bituminous material of the surface layer was verified as an affecting factor too, which can be introduced to improve the model's accuracy. Possible surface layer materials included dense (D) and semi-dense (S) asphalt concrete, with a maximum aggregate diameter of 16 and 22 mm, discontinuous mixing (BBTM 11A) and porous asphalt (PA 11). The additional model achieved a higher determination coefficient (0.645) and, hence, a more accurate IRI prediction resulted. [ABSTRACT FROM AUTHOR]

• Two skid resistance prediction models for an entire road network were developed. • Pavement structure information does not affect the skid resistance of surface layer. • The short model included the surface material, traffic volume, and number of lanes. • The long model added the required Polished Stone Value based on Spanish standards. • Models use Annual Average Daily Traffic of total traffic, not just heavy traffic. This article predicts the available minimum skid resistance in the road network of Biscay (Spain) with data collected in the summer season when friction values are at a minimum. Firstly, it was observed that pavement structure does not influence skid resistance. Therefore, roadway segments with available data about the surface layer of single or double carriageway roads were analyzed. Two models were developed: 1) short model with only the surface material, average annual daily traffic, and number of lanes (no pavement history required) and 2) a long model which adds the required Polished Stone Value to improve the prediction. These models can help road agencies to identify the roads where lower skid resistance values are more probable to be obtained to focus their attention and efforts. [ABSTRACT FROM AUTHOR]

The aim of this research is to amend the current contracting system to improve the quality of inter-urban bus services in metropolitan areas and thereby increase demand and reduce externalities. A methodology is proposed for tendering transport contracts which is applied in the Spanish region of Castilla and León. Based on a previous demand model, new incentives are proposed to encourage the operating companies to make improvements in the quality of service they provide on their metropolitan bus routes. The main contribution made by this research with respect to other similar methodologies is found in the incorporation of the subjective value of time and willingness to pay in exchange for improvements in service quality. This information is used to determine the optimal formula for public subsidies. The results show that, without any increase in costs for the administration, the amount of the subsidy due for underuse of the service could be reduced by increasing demand through providing a more attractive public transport service. It has also been shown that improvements in quality could be profitable, not only for society at large but also for the operating companies themselves. [ABSTRACT FROM AUTHOR]