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Historical masonry arch bridges constitute the backbone of many existing transportation networks in different countries in Europe and worldwide. They represent valuable cultural heritage assets and play an essential social and economic role. Since construction, old masonry bridges have accumulated structural damage from traffic and environmental actions. Furthermore, depending on their geometrical and mechanical characteristics, they may be particularly vulnerable to extreme events like earthquakes. Thus, accurate structural assessment under different loading conditions is critical for the conservation of these structures. Realistic assessment requires suitable numerical models to represent the characteristic 3D behaviour. The complexity of this task is further compounded by the practical difficulty in obtaining essential information on the internal bridge structure and the masonry mechanical parameters, which are vital to achieve accurate response predictions against service and extreme actions. This paper presents an advanced calibration procedure for a refined macroscale bridge model, allowing for the anisotropic nature of the masonry material. The proposed calibration approach is applied to an actual multi-span masonry viaduct, where sonic, ultrasonic, and ground penetrating radar tests are conducted to investigate the internal structure of the viaduct and determine the elastic properties of the masonry materials. In addition, the dynamic characteristics of the bridge are evaluated through in-situ measurements under environmental vibrations and used for model validation. The results from a standard simplified model calibration and an enhanced calibration are compared considering the vibration modes of the bridge. Simplified calibration is carried out using the results from in-situ tests, while a statistic inference procedure and numerical optimisation are adopted in the refined calibration to achieve improved accuracy. Although the paper focuses on a specific case study, the adopted methodology can be easily applied to studying other masonry bridges and cultural heritage masonry structures. • An advanced calibration procedure for a refined bridge macroscale model is presented. • The proposed calibration approach is applied to a multi-span masonry viaduct. • In-situ non-destructive tests are used to evaluate the internal structure of the bridge and the elastic material parameters. [ABSTRACT FROM AUTHOR]

Permanent deformation, fatigue and thermal cracking are the three typical distresses of flexible pavement. Using hydrated lime (HL) into the conventional limestone mineral additive has been widely practiced, including in Europe, to improve the mechanical properties of hot mix asphalt (HMA) concrete and as the result the durability of the constructed pavement. Large number of experimental studies have been reported to find the optimum addition of HL for the improvement on HMA concrete mechanical properties, moisture susceptibility and fatigue resistance. Pavement in service is under complex thermomechanical stress-strain conditions due to coupled atmospheric and surrounding environment temperature variation and the traffic loading. To predict and analyse the performance of pavement structures the data only from uniaxial compressive test for the resilient modulus and permanent deformation would be not enough. However, so far, the data of HL modified HMA concrete under complex loading conditions are still not well informatively complete. To contribute new knowledge, this paper reports an experimental study of both uni- and tri-axial tests for the asphalt concrete using HL into mineral additive for the mixes designed for the applications of wearing, levelling, and base layers, respectively. All the tests were conducted under three controlled temperatures and four stress deviations. The test results have showed that, for all three types of mixes, the permanent deformation of the HL mixes is less than the ones of no HL addition. The degree of the improvement on permanent deformation resistance using HL is much pronounced at high stress deviation states. The results have also showed that the resilient modulus strongly depends on the temperature and stress deviation while the mixes of HL addition demonstrate higher rigidity. At last, mathematical characterization models have been proposed for the measured material properties. A numerical simulation case study has been performed to test and demonstrate the application of the proposed unified property model. • Experimental work on uni- and tri-axial tests for asphalt concrete mixes using and without using the hydrated lime filler modification. • Novel mathematical characterization modelling on the experimental results for the resilient modules and permanent deformation. • Numerical case study simulation to demonstrate the application of the mathematical model proposed and developed in this work. [ABSTRACT FROM AUTHOR]

• A new type of application method of Fe-SMA bars in new structures was proposed. • The Fe-SMA bars can generate a prestress of 218–343 MPa in the concrete environment. • The additional end thread anchorage system can improve the effective prestress of the Fe-SMA bar in concrete. • A prediction model of the long-term prestressing retention of the Fe-SMA bar was proposed. As a new type of material for prestressed strengthening, iron-based shape memory alloys (Fe-SMA) have been extensively studied by the Swiss Federal Laboratories for Materials Science and Technology (Empa) and used in many demonstration structural strengthening projects across Europe. However, research on Fe-SMA in new structures remains insufficient. Therefore, aiming at the application in new structures, this paper proposed a new application method by combining the Fe-SMA bar and the corrugated plastic pipe, i.e., placing the Fe-SMA bar into the corrugated plastic pipe and filled with high-temperature resistant mortar. The effects of the prestrain level, activation temperature, and additional end threaded anchors on the prestress generated in the Fe-SMA bar were tested. In addition, to analyze the difference between the concrete-covered environment and the air-exposed environment on the generated prestress, tests on bare Fe-SMA bars were performed. A prediction model of the long-term prestressing retention of the Fe-SMA bar was proposed based on the monitored data. The test results show that the Fe-SMA bars can generate a prestress of 218–343 MPa in the concrete environment. With the increase in prestrain level and activation temperature, the prestress generated in the Fe-SMA bar increases. The additional end thread anchorage system can improve the effective prestress of the Fe-SMA bar in concrete. In addition, the prestress loss mainly occurred in the early stage and gradually slowed down with time; for example, the prestress loss after activated for 24 h accounted for approximately 42.3%∼55.1% of the total loss in 1000 h. The prediction results show that the prestress retention of the Fe-SMA bar with a reasonable prestrain level and activation temperature can be stably maintained above 79% after 50 years of service. [ABSTRACT FROM AUTHOR]

• Experimental tests were carried out for the evaluation of water repellents for masonry. • Infrared thermography was used to monitor the wetting and drying of laboratory walls. • Wetting and drying test were also carried out on treated/untreated bricks samples. • Multitemporal IRT images were processed by Change Detection Analysis (CDA) • Interesting data were obtained on water repellents' effectiveness and compatibility. Moisture is one of the main problems that affect new and historic masonry buildings, which are the most common ones in Europe and worldwide. The application of surface treatments based on water-repellents is a very common solution to protect masonry from rain and hence from moisture-related problems. However, there are very few studies on the monitoring of water-repellents in real buildings and a deeper knowledge would be necessary on the long-term effectiveness and compatibility of water repellents, especially considering that defects and flaking issues are often reported in-the-field. In this paper, infrared thermography was proposed as a totally non-invasive technique to monitor the behaviour of brick masonry subjected to wetting, both from outside (rain) and inside (internal moisture). An active thermal approach was used to simulate internal and external wetting. The behaviour of the masonry during wetting and drying was investigated both in laboratory walls and in brick samples, to elucidate their water transport properties. All the materials were tested both in untreated conditions and after the application of two different hydrophobic coatings. The results show that the drying behaviour of treated masonry materials is a critical issue, as the coatings may strongly slow down the drying of internal moisture, even if the coefficient of resistance to water vapour diffusion of the products is very low. The results also suggest that the methodology used to process thermal images using multi-temporal analysis is a promising way to interpret the water transport in treated walls and to monitor real buildings where water-repellents were applied. [ABSTRACT FROM AUTHOR]

[Display omitted] • Development of TRC led to a broadened variety of FRP reinforcements • Different fibre-matrix-compositions of 20 manufacturers of FRP reinforcement are identified • Material properties and surface characteristics of their products vary greatly • No sharp distinction between FRP textile reinforcement and FRP bars For certain cases internal reinforcement made of Fibre-reinforced polymers (FRP) is a promising solution to the degradation of steel reinforcement caused by environmental exposure. In the past years, rising demand for non-corrosive and more durable reinforcement led to a rapid increase in European FRP reinforcement manufacturers, which have developed various products with wide-ranging properties. This paper summarises an extensive study on the properties of FRP reinforcement elements for newly built concrete constructions. The main focus is set on the product pallet, composition, production processes, surface treatment, mechanical properties, availability, and pricing. One-, two- and three-dimensional reinforcement are analysed and compared. [ABSTRACT FROM AUTHOR]