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In Pavement Management Systems (PMS), pavement performance models, or pavement deterioration (or evolution) models are regarded as a key element because they are able to forecast the future condition of the pavement based on available data. Hence, once pavement performance is predicted for next years, the optimal moment and treatment can be planned to be conducted, maximizing the existing limited budget for road maintenance and rehabilitation (M&R). There is a wide variety of characteristics that are assessed in a pavement, and additionally, there are various indices to measure those characteristics too. However, it can be said that there is a property, pavement roughness, measured by the International Roughness Index (IRI), which is the most widely employed index worldwide. Most of the road administrations around the world measure the roughness by means of IRI. The Regional Government of Gipuzkoa (RGA) manages the entire road network in the province of Gipuzkoa, except from the municipal roads. Using the IRI data, traffic and pavement structure information of the A-636 freeway of Gipuzkoa, the aim of this paper is to develop some IRI prediction models for freeways in Gipuzkoa, adjusted to the climate characteristics of the province. Results showed that accurate models can be created if adequate variables are included, such as the pavement type, achieving a determination coefficient of R2 = 0.827. This fact underlines the importance of recording as much information as possible, especially pavement structural section, in the PMS.

Many substances have been used to modify bitumens with the aim of enhacing their properties and performance, but the most widely used are the polymers. Polyurethane foam is a waste product from themal insulation, which is frequently deposited in landfills. Waste polyurethane foam was selected as a possible bitumen modifier in bitumens to produce two differente bituminous mixes: hot mix asphalts with a B 50/70 bitumen and mastic asphalt with B 35/50 bitumen. Different quantities of polymer were added to the bitumens, from 1 % to 5 % in weight of the bitumen. In both bitumens it was shown that 5% or more of polymer made samples became rough and with low workability and, hence, they were discarded. Specimens of both bituminous materials were produced with 4% of polymer. The Marshall test showed that modified hot mix asphalt obtained improvements in stability and a lower deformation when compared to non-modified mixtures. Similarly, the modifed mastic asphalts showed lower identation values than non-modified samples, being able to be employed in road with heavy traffic. Consequently, the waste polyurethane foam resulted in a promising bitumen modifier that enhances bitumen properties.; Sustantzia asko erabili dira betuna eraldatzeko haien propietateak eta errendimendua hobetzeko helburuarekin, baina gehien erabiltzen direnak polimeroak dira. Poliuretano-aparra isolatze termikotik sortzen den hondakin-produktu bat da, normalean zabortegietan amaitzen dena. Hondakin poliuretano-aparra betun eraldatzaile gisa aukeratu zen betunak eraldatzeko bi nahaste bituminoso ezberdinak ekoizteko: beroan egindako nahastea B 50/70 motako betunarekin eta mastika bituminosoa B 35/50 motako betunarekin. Polimerozko (poliuretano-aparrezko) kantitate ezberdinak betunetan gehitu ziren, betunaren pisuaren % 1etik % 5era. Betun bietan ikusi zen %5a baino gehiagoko polimeroa sartzeak laginak zakar bihurtzen zituen langarritasun eskasarekin eta, horren ondorioz, baztertu ziren. Bi nahaste bitumin

Due to the presence of various traffic calming measures (TCM) and traffic lights in urban areas, the speed of vehicles is maintained low. Nevertheless, a problem arises in the frontier between urban and non-urban areas because drivers must adapt their speed and behavior to new conditions. This risk becomes even greater in rural roads that penetrate small villages without a bypass and with a short urban segment, since drivers do not normally speed down in these segments. Various measures can be installed, but traffic lights that turn red if the speed limit is exceeded is not usually considered as a TCM in the literature. Therefore, this paper aims to analyze the efficiency of traffic lights turning red in case of exceeding speed limit. The village of Abalos in Spain was selected for this research, with an urban area of 630 m and this type of traffic lights in both directions. Results showed that drivers do not respect the speed limit - and hence, the red light - when they are placed separately. However, if they are placed next to a crosswalk, their effect is increased. Consequently, it is recommended to place these traffic lights with a crosswalk to reinforce the efficiency of both TCMs., Debido a la presencia de varias medidas de calmado de tráfico (MCT) y semáforos en zonas urbanas, la velocidad de los vehículos semantiene baja. No obstante, un problema aparece en la frontera entre áreas urbanas y no urbanas porque los conductores debenadaptar su velocidad y comportamiento a nuevas condiciones. Este riesgo se vuelve incluso mayor en las carreteras interurbanas quepenetran en pequeñas poblaciones sin circunvalación y con un corto tramo urbano, pues normalmente los conductores no reducensu velocidad en estos tramos. Varias medidas pueden ser instaladas, pero los semáforos que se ponen rojos si se sobrepasa el límitede velocidad no suelen considerarse como MCT en la literatura. Por lo tanto, el objetivo de este artículo es analizar la eficacia delos semáforos que se ponen rojos en caso de exceder el límite de velocidad. La población de Abalos en España fue seleccionadapara esta investigación, con un área urbana de 630 m y con este tipo de semáforos en ambas direcciones. Los resultados muestranque los conductores no respetan el límite de velocidad - y por tanto, el semáforo en rojo - cuando son colocados por separado. Sinembargo, si son colocados junto a un paso de peatones, se aumenta su efecto. En consecuencia, se recomienda disponer este tipo desemáforos junto con un paso de peatones para reforzar la eficacia de ambas MCT.

Due to the importance of road transport an adequate identification of the various road network levels is necessary for an efficient and sustainable management of the road infrastructure. Additionally, traffic values are key data for any pavement management system. In this work traffic volume data of 2019 in the Basque Autonomous Community (Spain) were analyzed and modeled. Having a multidimensional sample, the average annual daily traffic (AADT) was considered as the main variable of interest, which is used in many areas of the road network management. First, an exploratory analysis was performed, from which descriptive statistical information was obtained continuing with the clustering by various variables in order to standardize its behavior by translation. In a second stage, the variable of interest was estimated in the entire road network of the studied country using linear-based radial basis functions (RBFs). The estimated model was compared with the sample statistically, evaluating the estimation using cross-validation and highest-traffic sectors are defined. From the analysis, it was observed that the clustering analysis is useful for identifying the real importance of each road segment, as a function of the real traffic volume and not based on other criteria. It was also observed that interpolation methods based on linear-type radial basis functions (RBF) can be used as a preliminary method to estimate the AADT.

Traffic calming measures (TCMs) are implemented in urban areas to reduce vehicles’ speed and, generally speaking, results are obtained. However, speed is still a problem in rural roads crossing small villages without a bypass and with short-length urban areas, since drivers do not normally reduce their speed for that short segment. Hence, various TCM can be installed. It is necessary to maintain a calm area in these short segments to improve road safety, especially for pedestrian aiming to cross the road, and to save combustible by avoiding a constant increase-decrease of speed. Four villages were selected to evaluate the efficiency of radar speed cameras and panels indicating vehicle’s speed. Results showed that the presence of radar speed cameras reduces the speed in the direction they can fine, but with a lower effect in the non-fining direction. Additionally, a positive effect was observed in the fining direction in other points, such as pedestrian crossings. Nevertheless, the effect does not last long and speed cameras may be considered as punctual measures. If the TCMs are placed far from the start of the village they are not respected. Hence, it is recommended to place them near the real start of the build-up area. Lastly, it was verified that longer urban areas make overall speed decrease. However, when drivers feel that they are arriving to the end of the urban area, due to the inexistence of buildings, they start speeding up.

Due to the presence of various traffic calming measures (TCM) and traffic lights in urban areas, the speed of vehicles is maintained low. Nevertheless, a problem arises in the frontier between urban and non-urban areas because drivers must adapt their speed and behavior to new conditions. This risk becomes even greater in rural roads that penetrate small villages without a bypass and with a short urban segment, since drivers do not normally speed down in these segments. Various measures can be installed, but traffic lights that turn red if the speed limit is exceeded is not usually considered as a TCM in the literature. Therefore, this paper aims to analyze the efficiency of traffic lights turning red in case of exceeding speed limit. The village of Ábalos in Spain was selected for this research, with an urban area of 630 m and this type of traffic lights in both directions. Results showed that drivers do not respect the speed limit - and hence, the red light - when they are placed separately. However, if they are placed next to a crosswalk, their effect is increased. Consequently, it is recommended to place these traffic lights with a crosswalk to reinforce the efficiency of both TCMs., Debido a la presencia de varias medidas de calmado de tráfico (MCT) y semáforos en zonas urbanas, la velocidad de los vehículos se mantiene baja. No obstante, un problema aparece en la frontera entre áreas urbanas y no urbanas porque los conductores deben adaptar su velocidad y comportamiento a nuevas condiciones. Este riesgo se vuelve incluso mayor en las carreteras interurbanas que penetran en pequeñas poblaciones sin circunvalación y con un corto tramo urbano, pues normalmente los conductores no reducen su velocidad en estos tramos. Varias medidas pueden ser instaladas, pero los semáforos que se ponen rojos si se sobrepasa el límite de velocidad no suelen considerarse como MCT en la literatura. Por lo tanto, el objetivo de este artículo es analizar la eficacia de los semáforos que se ponen rojos en caso de exceder el límite de velocidad. La población de Ábalos en España fue seleccionada para esta investigación, con un área urbana de 630 m y con este tipo de semáforos en ambas direcciones. Los resultados muestran que los conductores no respetan el límite de velocidad - y por tanto, el semáforo en rojo - cuando son colocados por separado. Sin embargo, si son colocados junto a un paso de peatones, se aumenta su efecto. En consecuencia, se recomienda disponer este tipo de semáforos junto con un paso de peatones para reforzar la eficacia de ambas MCT.

Due to the presence of various traffic calming measures (TCM) and traffic lights in urban areas, the speed of vehicles is maintained low. Nevertheless, a problem arises in the frontier between urban and non-urban areas because drivers must adapt their speed and behavior to new conditions. This risk becomes even greater in rural roads that penetrate small villages without a bypass and with a short urban segment, since drivers do not normally speed down in these segments. Various measures can be installed, but traffic lights that turn red if the speed limit is exceeded is not usually considered as a TCM in the literature. Therefore, this paper aims to analyze the efficiency of traffic lights turning red in case of exceeding speed limit. The village of Ábalos in Spain was selected for this research, with an urban area of 630 m and this type of traffic lights in both directions. Results showed that drivers do not respect the speed limit - and hence, the red light - when they are placed separately. However, if they are placed next to a crosswalk, their effect is increased. Consequently, it is recommended to place these traffic lights with a crosswalk to reinforce the efficiency of both TCMs., Debido a la presencia de varias medidas de calmado de tráfico (MCT) y semáforos en zonas urbanas, la velocidad de los vehículos se mantiene baja. No obstante, un problema aparece en la frontera entre áreas urbanas y no urbanas porque los conductores deben adaptar su velocidad y comportamiento a nuevas condiciones. Este riesgo se vuelve incluso mayor en las carreteras interurbanas que penetran en pequeñas poblaciones sin circunvalación y con un corto tramo urbano, pues normalmente los conductores no reducen su velocidad en estos tramos. Varias medidas pueden ser instaladas, pero los semáforos que se ponen rojos si se sobrepasa el límite de velocidad no suelen considerarse como MCT en la literatura. Por lo tanto, el objetivo de este artículo es analizar la eficacia de los semáforos que se ponen rojos en caso de exceder el límite de velocidad. La población de Ábalos en España fue seleccionada para esta investigación, con un área urbana de 630 m y con este tipo de semáforos en ambas direcciones. Los resultados muestran que los conductores no respetan el límite de velocidad - y por tanto, el semáforo en rojo - cuando son colocados por separado. Sin embargo, si son colocados junto a un paso de peatones, se aumenta su efecto. En consecuencia, se recomienda disponer este tipo de semáforos junto con un paso de peatones para reforzar la eficacia de ambas MCT.

U radu se provodi eksperimentalna provjera posmične čvrstoće montažnih betonskih rebrastih ploča različitih visina s električno zavarenom armaturnom rešetkom. Prikazano je tehničko obrazloženje korištenja visokih rešetki u armaturi montažnih lakih rebrastih ploča u obliku dvostrukog slova T i montažnih armiranobetonskih ploča debljine 30 cm. Utvrđeno je da je doprinos betona posmičnoj čvrstoći uvijek veći od vrijednosti koje se mogu očekivati prema španjolskim normama. Osim toga, kako se niske rešetkaste rebraste ploče odlikuju nižim vrijednostima granične posmične čvrstoće od onih koje se očekuju prema normama, utvrđeno je da se treba osigurati odgovarajuća visina rešetaka u rebrastim pločama kako bi se osiguralo sidrenje tlačne zone te razvoj mehanizama štapova i zatega. Zato se u armiranobetonskim rebrastim pločama svakako preporučuje korištenje rešetkastih nosača na otprilike 80 % visine uzorka kada dužina pojasa rešetke iznosi 20 cm., Shear strength of precast concrete ribbed slabs reinforced with electro-welded lattice girders of variable height is experimentally verified. Technical justification is given for the use of high latticework in the reinforcement of precast lightweight double-tee ribbed slabs and precast reinforced concrete slabs 30 cm in thickness. It was established that the contribution of concrete to shear strength was always higher than the expected values according to Spanish standards. Furthermore, as low lattice ribbed slabs exhibited lower ultimate shear strength values than the ones expected based on the standards, the need arose to provide an adequate height of lattices in ribbed slabs to ensure anchorage of the compressed area in order to develop the strut-and-tie mechanisms. Consequently, lattice girders with approximately 80% of specimen height are highly recommended in reinforced concrete ribbed slabs, when the length of lattice chords is 20 cm.

Due to the considerable amount of waste plastics and polymers that are produced annually, the introduction of these waste products in construction materials is becoming a recurrent solution to recycle them. Among polymers, polyamide represents an important proportion of polymer waste. In this study, sustainable and lightweight mortars were designed and elaborated, substituting the aggregates by polyamide powder waste. Mortars were produced with various dosages of cement/aggregates, and the polyamide substitutions were 25, 50, 75, and 100% of the aggregates. The aim of this paper is to determine the density and the compressive strength of the manufactured mortars to observe the feasibility for being employed as masonry or rendering and plastering mortars. Results showed that with increasing polymer substitution, lower densities were achieved, ranging from 1850 to 790 kg/m3 in modified mortars. Mortars with densities below 1300 kg/m3 are cataloged as lightweight mortars. Furthermore, compressive strength also decreased with more polyamide substitution. Obtained values in recycled mortars were between 15.77 and 2.10 MPa, but the majority of the values (eight out of 12) were over 5 MPa. Additionally, an economic evaluation was performed, and it was observed that the use of waste polyamide implies an important cost reduction, apart from the advantage of not having to manage this waste material. Consequently, not only the mechanical properties of the new recycled materials were verified as well as its economic viability.

Pavement performance models play a vital role in any pavement management system. The Regional Government of Biscay (RGB) (Spain) manages a 1200 km road network and conducts pavement data collections, including the International Roughness Index (IRI) values. The aim of the paper is to develop an IRI performance model for two-lane roads with flexible pavement until the first maintenance and/or rehabilitation activity is performed. Due to the huge amount of available information, a deterministic model was selected. A literature review of deterministic models showed that, apart from age and traffic volumes, the pavement structure is a key factor. Therefore, it was decided to analyze the only road stretches whose entire pavement section was known (surface layer + base + subbase). Various variables related to age, traffic volumes and employed materials were introduced as possible factors. The multiple linear regression model with the highest coefficient of determination and all the variables significant included the real pavement age, the cumulated heavy traffic and the total thickness of bituminous layers. As the material employed in the surface layer could affect roughness progression, a qualitative variable was introduced to consider various surface materials. The model improved its accuracy, indicating that the surface layer material is also an influencing factor on IRI evolution.

Traffic calming measures (TCM) are placed in urban areas to improve road safety, and among them, vertical TCMs are widely employed. Many researches are focused on the influence of the geometry of each measure on speed reduction, but it is demonstrated that drivers forget its effect and speed up after it. Therefore, placing consecutive TCMs can help to maintain a safe area. However, scarce literature can be found about the adequate spacing between them. Hence, the aim of this paper is to analyze the adequate distance between TCMs. Various streets with variable distances and different vertical TCMs were evaluated in Poland and Spain, including raised crosswalks, raised intersections, speed humps and speed cushions. The intermediate point between two TCMs was selected as the place where the maximum speed is achieved. Results showed that there was a good correlation between the speeds at intermediate points and the distance between TCMs, with a determination coefficient around 0.80. For an 85th percentile of the speed under 50 km/h, a maximum distance of 200 m between TCMs is recommended, and for a value of 40 km/h, 75 m.

Proiektu hau Murueta herrian, trenbide baten gainetik pasatzen den pasarelaren ejekuzio proiektua da.

[EN]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.

Roman cities and roads, once correctly identified, can be appropriately conserved. Moreover, the correct identification of Roman transport routes will vindicate the accuracy of recent studies on the network of Roman transport infrastructure and its connectivity, functionality, and impact. With this aim in mind, a novel method is presented for computing the most likely location, from among the various proposed locations that may exist, of any Roman city that is cited both in a Roman itinerary and in Ptolemy’s Geographia. In the first phase, the geographical area where the city was located is demarcated by means of the itinerary. In the second phase, Ptolemy’s coordinates of well-known Roman cities from the province of the Roman Empire that is under consideration are correlated with those of the WGS 84 reference system by means of simple linear regressions. Having confirmed the normality of the regression error distribution, the bivariate normal distribution is computed, and the confidence intervals are determined. This method is implemented, to identify the most probable location of the Vaccaean city of Intercatia in Hispania, and to propose a new route for the Roman road that once passed through it.