Various studies have been recently conducted to predict pavement condition, but most of them were developed in a certain region where climate conditions were kept constant and/or the research focused on specific road distresses using single parameters. Thus, this research aimed at determining the influence of pavement structure, traffic demand, and climate factors on urban flexible pavement condition over time. To do this, the Structural Number was used as an indicator of the pavement capacity, various traffic and climate variables were defined, and the Pavement Condition Index was used as a surrogate measure of pavement condition. The analysis was focused on the calibration of regression models by using the K-Fold Cross Validation technique. As a result, for a given pavement age, pavement condition worsens as the Equivalent Single Axle Load and the Annual Average Height of Snow increased. Likewise, a cold Annual Average Temperature (5–15 °C) and a large Annual Average Range of Temperature (20–30 °C) encourage a more aggressive pavement deterioration process. By contrast, warm climates with low temperature variations, which are associated with low precipitation, lead to a longer pavement service life. Additionally, a new classification of climate zones was proposed on the basis of the weather influence on pavement deterioration.

Boosting sustainability in public construction procurement implies new challenges associated with incentivizing integrated approaches and the inclusion of sustainability criteria in tendering procedures. Thus, the choice of project-delivery method and procurement procedure is a key decision to ensure project success for sustainable outcomes. This study focused on the social dimension of sustainability and analyzed 451 tendering documents from 10 countries to assess the influence of procurement procedures and delivery methods on the inclusion of social criteria in public construction procurement. Content analysis, descriptive statistics, and logistic regression were applied. The results show the international trends in delivery methods and procurement procedures. Country and contract size were found to be the most influential variables for the inclusion of social criteria in tendering procedures. There were no significant differences between project-delivery methods and between procurement procedures with respect to the inclusion of social criteria. However, criteria associated with employment and cultural heritage were mainly considered in traditional delivery methods, whereas professional ethics and cultural heritage were associated with the lowest price procurement procedures. Finally, subjective methods were predominantly used to assess social sustainability.

Undergrounds and other metropolitan railway systems are characterized by their intense traffic, lasting up to 20 h per day, and so they need their maintenance work programmes to be optimized, implying an optimization of the monitoring processes. This article proposes an alternative to the traditional optical methods for monitoring rail profiles which can only be carried out by special vehicles. This is a new procedure that obtains the rail profile by means of inertial methods. The model this work is based on takes its input from the vertical accelerations produced in railway axles measured in trains running on regular services and calculates the rail irregularities that have originated them. The model uses the Fourier transform in order to solve the equations and find the transfer function that relates the input function and the output function in the frequency domain. The solution is then reverted into the time domain by applying the inverse Fourier transform. Data input comes from real measurements taken on line 9 of the Madrid underground, and the model's effectiveness was then analysed by comparing the output data with the rail profile taken using optical methods.

Currently, reuse of solid waste from disused infrastructures is an important environmental issue to study. In this research, polymer concrete was developed by mixing orthophthalic unsaturated polyester resin, artificial microfillers (calcium carbonate), and waste aggregates (basalt and limestone) coming from the recycling process of concrete sleepers. The variation of the mechanical and physical properties of the polymer concrete (compressive strength, flexural strength, modulus of elasticity, density, and water absorption) was analyzed based on the modification of different variables: nature of the recycled aggregates, resin contents (11 wt%, 12 wt%, and 13 wt%), and particle-size distributions of microfillers used. The results show the influence of these variables on mechanical performance of polymer concrete. Compressive and flexural strength of recycled polymer concrete were improved by increasing amount of polyester resin and by optimizing the particle-size distribution of the microfillers. Besides, the results show the feasibility of developing a polymer concrete with excellent mechanical behavior.