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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]

• Walls with current and alternative materials to control noise in buildings. • Evaluation of the environmental, economic and social sustainability. • Characterization in terms of embodied energy, acoustic behaviour and costs. • Alternative materials are viable to replace current ones in wall assemblies. This paper presents several solutions of walls currently used in the construction and rehabilitation of buildings including the acoustic insulation materials most used in Europe. An exhaustive study was made, including 78 single and double-leaf wall assemblies. Their acoustic insulation, embodied energy and economical characteristics were analysed, to assess the potential of use of natural, and innovative, materials as substitutes of traditional materials. The acoustic performance - airborne sound insulation - was studied using predictive models, considering the characteristics of the materials considered in each layer of the wall. Regarding the embodied energy and costs, both resulted from the sum of the contribution of those materials. It was found that the incorporation of natural materials in wall assemblies is, from the acoustical behaviour, embodied energy and costs points of view, a viable option as replacement of traditional materials. This assessment was validated using a significant and representative set of alternative wall solutions. [ABSTRACT FROM AUTHOR]

• The low cycle ductile performance of screws used in timber structures is examined. • A testing programme is conducted as prescribed in the revised version of EN 14592. • The results of approximately 200 experiments are presented and critically discussed. • Some recommendations for the future developments of EN 14592 are provided. Self-tapping screws are largely used in both lightweight and massive timber constructions, being able to carry out simultaneously axial (withdrawal) and lateral (shear) loads. In Europe, the requirements of such fasteners are described in EN 14592; however, the standard used until today addresses only their applications under monotonic conditions and it lacks of prescriptions when the screws are used to withstand cyclic loads. Recently, the standard has undergone a significant revision and some specific rules for screws used in seismic areas have been introduced. Specifically, the revised version of EN 14592 defines three low cycle ductility classes, to which a fastener must be assigned based on the outcomes of monotonic and cyclic bending tests. Following the new seismic provisions included in EN 14592, this paper describes the results of an independent study aimed at assessing the low cycle ductile performance of self-tapping screws that are currently available on the market. Approximately 200 experiments are presented and critically analysed, demonstrating that screws with a diameter of 6 mm must be assigned to the lowest low cycle ductility class. Conversely, all screws with diameter greater than or equal to 8 mm have the potential to be assigned to the highest low cycle ductility class. [ABSTRACT FROM AUTHOR]

• CM has potential for use in Europe but design rules in Eurocode 6 are not suitable. • A comprehensive review of approaches on structural behaviour of CM walls is made. • Contribution of materials to vertical resistance is evaluated and a formula proposed. • Shear and flexural behaviours are reviewed and the available models are compared. • Detailing requirements in design are revised for implementation in a structural code. Confined masonry (CM) has been adopted as a cost-effective and earthquake-resistant solution for buildings, mostly in developing countries. CM has large potential for use in Europe, but suitable rules for its application are not available in the European masonry code. This paper presents a critical review of theoretical approaches and experimental investigations on the structural behaviour of CM walls, along with the proposal of simple but suitable design rules. The behaviour to vertical compression and to in-plane shear and bending loadings are comprehensively reviewed with reference to existing studies. Concerning the vertical compressive behaviour, the contribution of each material to the vertical resistance is evaluated and a formulation is proposed. The existing theories for the shear and flexural behaviours are reviewed and the available and new proposed models are compared against experimental results. Finally, requirements for detailing of CM are reviewed from international design codes, in view to propose suitable rules for implementation in a structural code. [ABSTRACT FROM AUTHOR]

Highlights • Structural assessment of historical bridges requires the knowledge of many experts. • Structural assessment is helped by the reconstruction of historical events. • The assessment of a historical bridge requires a very strong coordination. • A limited budget can be instrumental to refine the assessment approach strategy. Abstract Ponte Azzone Visconti is a strategic middle age bridge built at north of Milan astride river Adda, along the road towards the centre of Europe passing from the Valtellina, the lordship of Milan and the Serenissima Republic. An on-site assessment of the bridge was carried out starting from the requirement expressed by the municipality of Lecco, consisting in the evaluation of the actual bearing capacity of the infrastructure with reference to the bridge classes defined in the national standards. The investigation used several approaches to quantify the bridge structural safety with reference to the vertical loads due to traffic and accidental seismic events and to highlight any critical issue. The paper is aimed at suggesting the most convenient analysis and maintenance choices, in order to conjugate the very significant historical value of the bridge to a sustainable evolution of its function. [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]

• A complete mechanical characterization of Arundo donax was carried out. • The axial Young's moduli were 12.0 GPA and 14.8 GPa under compression and tension. • Methods are proposed to characterize the shear, axial and transverse tensile behavior. • The anisotropy and mechanical properties of AD are similar to those of bamboo used in construction. • DIC was used to analyze the role of the anisotropy and natural nodes under various loading conditions. There is a growing recognition and awareness that nature can provide viable solutions for more sustainable building materials. Arundo donax (AD) is a tall cane of about 20–30 cm in diameter that grows widely and rapidly in many regions of Europe. AD, like bamboo in the subtropical areas, may be rediscovered as a source of inexpensive sustainable material for various construction purposes. To promote the use of AD following the engineering practice, this paper was aimed at showing the potentiality of this material through an extensive mechanical characterization. The tests were performed on portions of culms using ad hoc setups following recommendations or modifications of bamboo standards. Digital image correlation was used to follow the map of strains needed to understand the role of the natural nodes under different loading conditions. The axial Young's moduli were 12.0 GPa and 14.8 GPa under compression and tension, respectively, and the corresponding maximum failure stresses were 57 MPa and 127 MPa for the internodal material. Shear and transverse bending tests yielded results consistent with the anisotropy of the material. The results show the good mechanical properties of Arundo donax that are similar to those of various species of bamboo used in constructions. [ABSTRACT FROM AUTHOR]

• Two types of beet-pulp/starch bricks are investigated: full and hollowed bricks. • The preparation of the mixture and bricks manufacturing are described in details. • The microstructure of the mixture constituents are described and analyzed. • The drying kinetics of the bricks are compared and predicted via mathematical models. • The mechanical behavior of the bricks is studied via compressive tests on each type. Buildings account for a large share of the primary energy and materials use in Europe. Therefore, the EU has set several energy and materials targets for the built environment and other sectors. Novel low-carbon materials can play a major role in the transition towards meeting those targets. Moreover, agriculture produces by- or waste products that could be used as constituent of innovative agro-materials for construction. Recently, beet pulp based-material is being investigated on the material scale and promising results are pointed out regarding its interesting mechanical, hygrothermal and acoustical properties for building insulation use. In this context, the paper aims to study experimentally two types of beet-pulp starch composites: whole bricks and hollowed bricks. The manufacturing of the two types of bricks is detailed. A comparative study is then achieved regarding the drying kinetics, mechanical properties as well as internal structure composition. [ABSTRACT FROM AUTHOR]

• Augmented maturity method using FEM-based numerical tests in addition to the usual laboratory and field experimental methodology. • Recommendations for an effective laboratory research program and a reliable temperature measurement system. • FEM analysis of compressive strength distribution in the concrete deck of extradosed bridge. • The complex system of concrete monitoring improves the confidence of decisions on prestressing tendons or formwork removal and provides economic benefit. The work is devoted to the implementation of a monitoring system for high performance concrete embedded in the span of an extradosed bridge deck using a modified maturity method augmented by numerical simulations conducted by the authors' FEM code. The paper presents all research stages of bridge construction and considers the conclusions drawn from the results of laboratory tests, field measurements, and numerical calculations. The monitored structure is the largest extradosed bridge in Europe in terms of the span's length. Due to the considerable size and duration of the investment, it was beneficial to use an alternative method for estimating the compressive strength of concrete based on the maturity function. The bridge sections were investigated in three stages: in summer, autumn, and early spring (in June, September, and March). The monitoring of in-place concrete provided information on the actual temperature of the concrete and its gradients. Based on recorded temperatures and proposed numerical procedures, the actual strength of the cast-in-place concrete and the optimal dates of prestressing were determined. This contributed to shortening the work cycle and speeding up the work schedule. [ABSTRACT FROM AUTHOR]