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Thermal energy storage represents a crucial element to increase solar power dispatchability. Within sensible heat storage in solid media, concrete is considered a low-cost alternative to be further developed and therefore, this has been addressed in this paper. Four concrete dosages were designed, combining each type of considered cement, ordinary Portland and calcium aluminate cement, with each type of considered aggregate, silico-calcareous and a steel slag. Thermo-mechanical properties of concrete were studied before and after 10 thermal cycles from 290 ¿C to 700 ¿C. Maximum operating temperature and heating rates were selected accordingly to the targeted application, a concentrating solar power (CSP) tower plant. At macro-level, results show thermal cycle stability of concrete with steel slag aggregate in both cement types. On the contrary, at micro-level, the petrography analysis shows the lack of bonding between steel slag aggregate and the cement paste. In contrast, concrete mixtures containing silico-calcareous aggregates collapse after thermal cycling., Peer Reviewed, Postprint (published version)

The mechanical behaviour of laminated glass plates and beams is affected in different ways by the shear stiffness of interlayer materials. Polymeric interlayers are viscoelastic materials, and therefore experience creep when subjected to long-term loading. In this paper, three laminated glass panels, each with a different interlayer material (PVB Clear, PVB ES, and SentryGlas), were placed between two laminated glass beams. A uniformly distributed load was applied during four months to study the effect of creep, and then was removed to see the deflection recovery during one month. The midspan vertical displacement of the two laminated glass beams remained almost constant over time, with a small variation that was attributed to the rubber sheets placed in the supports. The plate with SentryGlas had the lowest elastic deformation, creep, and residual deformation. The plate with PVB Clear had the highest elastic and total deformation. The plate with PVB ES had a similar initial deflection as SentryGlas, but was the one that experienced the highest creep. At the end of the test the plates still had a small residual deflection, which could be due to an incomplete deflection recovery. The flexural behaviour of the three laminated glass plates was simulated using a Finite Element Model, representing the loading, the creep, the unloading, and the deflection recovery stages., The work was partially funded by CRISTEC with CDTI funds (IDI-20160588). The authors at the University of Lleida would like to thank the Catalan Government for the quality accreditation given to their research group GREiA (2017 SGR 1537). GREiA is certified agent TECNIO in the category of technology developers from the Government of Catalonia. This work is partially supported by ICREA under the ICREA Academia programme. The financing support given by the Spanish Ministry of Economy and Competitiveness through the project BIA2014-53774-R is gratefully appreciated. Xavier Centelles would like to thank University of Lleida for his research fellowship and to the University of Oviedo. for hosting his secondment during 2019, Peer Reviewed, Postprint (published version)

Laminated glass beams without metallic or polymeric reinforcements generally lack post-breakage strength and ductility. This paper aims to perform a comparative study by testing five different fully transparent laminated glass beam designs in order to see how parameters such as the number and thickness of glass sheets (3 x 10 mm or 5 x 6 mm), the interlayer material (PVB Clear or SentryGlas), and the thermal treatment of glass (annealed or heat-strengthened) affect the pre-breakage performance and post-breakage safety. A buckling analysis is also performed using a numerical model with ABAQUS CAE. The study includes a comparison between the results of different experimental mechanical tests on laminated glass beams, including the tests presented in this paper, as well as other tests found in the literature. All designs presented a linear elastic behaviour until initial breakage. The interlayer material mainly affected the crack shape of laminated glass beams. Beams with five sheets of annealed glass had a more progressive breakage, and therefore a safer behaviour, than beams with three sheets of annealed or heat-strengthened glass., The work was partially funded by CRISTEC with CDTI funds (IDI-20160588). The authors at the University of Lleida would like to thank the Catalan Government for the quality accreditation given to their research group GREiA (2017 SGR 1537). GREiA is certified agent TECNIO in the category of technology developers from the Government of Catalonia. This work is partially supported by ICREA under the ICREA Academia programme. The financing support given by the Spanish Ministry of Economy and Competitiveness through the project BIA2014-53774-R is gratefully appreciated. Xavier Centelles would like to thank University of Lleida for his research fellowship and to the University of Oviedo for hosting his secondment during 2019. Funding Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature., Peer Reviewed, Postprint (published version)

Laminated glass is a composite laminate obtained from combining two or more glass layers with a polymeric interlayer. The adhesion between glass and interlayer, as well as the shear strength and stiffness of the interlayer, are key factors to evaluate the cohesive behaviour of laminated glass. Glass is a very durable material, while polymeric interlayers can be deteriorated by exposure to weathering factors. A double-lap shear test was carried out on laminated glass specimens, with four different interlayer materials (PVB BG-R20, Saflex DG-41, SentryGlas, and EVASAFE), after different ageing tests (unaged, thermal cycles, humidity, and UV radiation). The material selection affected the shear behaviour of the bond between glass and interlayer, and so did the previous exposure to certain ageing factors. Since the polymeric interlayers are viscoelastic materials, and therefore its mechanical properties are time- and temperature-dependant, the results here presented should be complemented with dynamic and static tests at different temperatures., The work was partially funded by CRISTEC with CDTI funds (IDI-20160588). The authors would like to thank the Catalan Government for the quality accreditation given to their research group GREiA (2017 SGR 1537). GREiA is certified agent TECNIO in the category of technology developers from the Government of Catalonia. This work is partially supported by ICREA under the ICREA Academia programme. Xavier Centelles would like to thank University of Lleida for his research fellowship., Peer Reviewed, Postprint (author's final draft)

Laminated glass is obtained by bonding two or more glass layers with a polymeric interlayer. The coupling between glass layers depends on the shear stiffness of the interlayer. The mechanical and optical properties of the interlayer may be affected by weathering factors. Since interlayer materials are viscoelastic, the strain rate may also affect its stiffness and ultimate strength. In this paper, tensile tests are conducted on seven different polymeric films (PVB BG-R20, PVB DG-41, PVB ES, SentryGlas, EVASAFE, EVALAM 80, and TPU) at three different strain rates. The mechanical and optical properties of unaged specimens are compared with specimens exposed to thermal cycles, high temperatures, and moisture. The unaged specimens of PVB DG-41, PVB ES, and SentryGlas had the highest stiffness, EVALAM 80 and EVASAFE had the highest ductility, PVB and SentryGlas had the highest tensile strength, and EVALAM 80, EVASAFE, and TPU were less affected by ageing factors and strain rate., The work was partially funded by CRISTEC with CDTI funds (IDI-20160588). The authors would like to thank the Catalan Government for the quality accreditation given to their research group GREiA (2017 SGR 1537). GREiA is certified agent TECNIO in the category of technology developers from the Government of Catalonia.This work is partially supported by ICREA under the ICREA Academia programme. Xavier Centelles would like to thank University of Lleida for his research fellowship. Aran Solé would like to thank Ministerio de Economía y Competitividad de España for Grant Juan de la Cierva, FJCI-2015-25741., Peer Reviewed, Postprint (author's final draft)

Laminated glass combines glass layers, which provide strength and durability, with transparent polymeric interlayers, which provide coupling between glass layers and prevent glass shards from scattering in case of breakage. The main goal of this paper is to present, through COMSOL Multiphysics simulations, how the mechanical performance (bending stiffness and stress distribution) of laminated glass plates is affected by the shear stiffness of the interlayer material. The simulation results were validated with experimental tests. The laminated glass specimens presented a linear elastic behaviour until glass breakage, and its mechanical performance was affected by the interlayer material selection, as well as the load duration and the working temperature., The work was partially funded by CRISTEC with CDTI funds (IDI-20160588). The authors would like to thank the Catalan Government for the quality accreditation given to their research group GREiA (2017 SGR 1537). GREiA is certified agent TECNIO in the category of technology developers from the Government of Catalonia. This work is partially supported by ICREA under the ICREA Academia programme. Xavier Centelles would like to thank University of Lleida for his research fellowship., Peer Reviewed, Postprint (published version)

Laminated glass combines glass layers, which provide strength and durability, with transparent polymeric interlayers, which provide coupling between glass layers and prevent glass shards from scattering in case of breakage. The main goal of this paper is to present, through COMSOL Multiphysics simulations, how the mechanical performance (bending stiffness and stress distribution) of laminated glass plates is affected by the shear stiffness of the interlayer material. The simulation results were validated with experimental tests. The laminated glass specimens presented a linear elastic behaviour until glass breakage, and its mechanical performance was affected by the interlayer material selection, as well as the load duration and the working temperature., The work was partially funded by CRISTEC with CDTI funds (IDI-20160588). The authors would like to thank the Catalan Government for the quality accreditation given to their research group GREiA (2017 SGR 1537). GREiA is certified agent TECNIO in the category of technology developers from the Government of Catalonia. This work is partially supported by ICREA under the ICREA Academia programme. Xavier Centelles would like to thank University of Lleida for his research fellowship., Postprint (published version)