Combined seismic and energy upgrading of existing buildings using advanced materials

Of the current EU building stock, 80% was built before the 90's, while 40% are pre-60's and a considerable amount being even older and classified as cultural patrimony, thus requiring preservation techniques if we want to maintain this cultural heritage for our future generations. Upgrading the existing EU buildings and the cultural heritage ones is becoming increasingly important due to: (1) their poor seismic performance during recent earthquakes (i.e. Italy, Greece) that have resulted in significant economic losses, severe injuries and loss of human lives; and (2) their low energy performance which increases significantly their energy consumption. However replacing a big part of the existing buildings is prohibitively expensive or not allowed for historical heritage buildings and would have a significant societal and environmental impact, their lifetime extension requires considering both seismic and energy retrofitting. The Exploratory research project iRESIST+ explores a novel concept, by applying a hybrid structural-plus-energy retrofitting solution which combines inorganic textile-based composites with thermal insulation systems for building envelopes. In this report, the iRESIST+ concept is examined through a number of case studies conducted on model buildings designed according to outdated regulations. Specifically, seismic and thermal analyses were conducted prior to and after the application of selected retrofitting schemes in order to quantify the positive effect that retrofitting could provide to RC buildings both in terms of their structural and energy performance. Advanced materials, namely the so-called Textile Reinforced Mortar (TRM) was used for providing seismic retrofitting by means of TRM jacketing of the masonry infills around the RC frames. Moreover, following the application of the TRM jackets, thermal insulation materials were simultaneously provided to the RC building envelope, exploiting the fresh mortar used to bind the TRM jackets. In addition to the externally applied insulation material, all the fenestration elements (window and doors) were replaced with new high energy efficiency ones. Afterwards, an economic measure, namely the Expected Annual Loss (EAL) was used to evaluate the efficiency of each retrofitting method, but also to assess whether the combined seismic and energy retrofitting is economically feasible. From the results of this preliminary study, it was concluded that the selected seismic retrofitting technique can indeed enhance significantly the structural behaviour of an existing RC building and lower its EAL related to earthquake risks. Finally, it was found that the combined seismic and energy upgrading is economically more efficient than a sole energy or seismic retrofitting scenarios for seismic areas of south Europe.JRC.E.4-Safety and Security of Building

MOLDAM additive manufacturing robotic cell for extruding thermoplastic pellets

[Resumen] Durante los últimos años la fabricación aditiva se está posicionando como una tecnología atractiva por su sencillez y accesibilidad en el mercado, posibilitando la extrusión de diferentes materiales. Sin embargo, las dimensiones del área de trabajo y las limitadas capacidades de extrusoras comerciales de pequeñas dimensiones están derivando en la investigación y puesta en marcha de máquinas más grandes con una mayor tasa de deposición de material. Este artículo describe una nueva celda robótica automatizada para la extrusión de materiales termoplásticos en formato de granza o pellet siendo posible la extrusión de material a alta tasas de deposición. En este sentido, el artículo define la arquitectura de la celda robótica, el interfaz de usuario y los resultados preliminares. Además, se ha desarrollado el gemelo digital para la monitorización del proceso de una manera virtual. Finalmente, el artículo describe un nuevo software registrado en el que se puede analizar las variables del proceso o el comportamiento del material impreso.[Abstract] During the last years, the additive manufacturing is becoming an attractive technology due to simplicity and market accessibility enabling the extrusion of different materials. However, the workspace requirements and the limitation of the small commercial extruders, are leading to research and develop big machines with higher material feed rate. This article describes a new robotic cell for extruding thermoplastic material in pellet format, being able to deposit high material feed rate. In this sense, this article defines the architecture of the cell, the user interfaces for controlling and monitoring the robotic cells and the preliminary results. Furthermore, a digital twin (DT) has been developed to monitor the process virtually. Finally, the paper describes a new registered software in which the data process or the behaviour of the printed material after testing can be shown

Πειραματική και αναλυτική διερεύνηση της αλληλεπίδρασης μεταξύ της εντός και εκτός επιπέδου συμπεριφοράς ενισχυμένων με ινοπλέγματα και θερμικώς μονωμένων τοιχοπληρώσεων​

The effect of in-plane damage on the out-of-plane response of reinforced and thermally insulated masonry elements and infills was examined in this dissertation experimentally and analytically. Structural reinforcement was realized through the use of textile reinforced mortar while regular expanded polystyrene was used for thermal in-sulation. Various specimen configurations were tested both in- and out-of-plane sequentially within a strong frame using hydraulic actuators to impose the respective loads. Experimental results have shown that the TRM-based strengthening scheme can improve the out-of-plane response of masonry infills both in terms of strength and stiffness, especially in the case of pre-damaged walls. The addition of insulation arranged in a "sandwich" configuration resulted in a slight out-of-plane improvement, but was not as effective in the case of pre-damaged specimens. Last but not least, numerical and analytical models are proposed which can predict the out-of-plane behavior of masonry elements and infills while also accounting for the existence of reinforcement and prior damage.Στην παρούσα διατριβή, εξετάστηκε πειραματικά και αναλυτικά η επίδραση της εντός του επιπέδου βλάβης στην εκτός επιπέδου απόκριση ενισχυμένων και θερμομονωμένων στοιχείων τοιχοποιίας και τοιχοπληρώσεων. Η ενίσχυση των δοκιμίων έγινε με χρήση ινοπλεγμάτων σε ανόργανη μήτρα, ενώ ως λύση θερμομόνωσης επιλέχθηκαν πλάκες διογκωμένης πολυστερίνης. Δοκιμάστηκαν διάφορες διατάξεις ενίσχυσης τόσο σε εντός όσο και σε εκτός επιπέδου πειραματικές δοκιμές, οι οποίες έλαβαν χώρα εντός ισχυρού πλαισίου, κάνοντας χρήση υδραυλικών εμβόλων για την επιβολή των αντίστοιχων φορτίων. Τα πειραματικά αποτελέσματα έδειξαν ότι το προτεινόμενο σχήμα ενίσχυσης με βάση τα ινοπλέγματα μπορεί να βελτιώσει την εκτός επιπέδου απόκριση των στοιχείων τοιχοποιίας και τοιχοπληρώσεων τόσο σε επίπεδο αντοχής όσο και δυσκαμψίας, ειδικά στην περίπτωση τοίχων που έχουν υποστεί ζημιά. Η προσθήκη μόνωσης σε διάταξη τύπου "σάντουιτς" οδήγησε σε ελαφρώς βελτιωμένη εκτός επιπέδου συμπεριφορά των δοκιμίων χωρίς βλάβη, αλλά δεν ήταν το ίδιο αποτελεσματική στην περίπτωση δοκιμίων με προϋπάρχουσα βλάβη. Τέλος, προτείνονται αριθμητικά και αναλυτικά μοντέλα που μπορούν να προβλέψουν την εκτός επιπέδου συμπεριφορά στοιχείων τοιχοποιίας και τοιχοπληρώσεων, λαμβάνοντας ταυτόχρονα υπόψη την ύπαρξη οπλισμού και ενδεχόμενης ζημιάς

Combined seismic and energy upgrading of existing reinforced concrete buildings using TRM jacketing and thermal insulation

The concept of the combined seismic and energy retrofitting of existing reinforced concrete (RC) buildings was examined in this paper through a number of case studies conducted on model buildings (simulating buildings of the ‘60s - ‘80s in southern Europe) constructed according to outdated design standards. Specifically, seismic and thermal analyses have been conducted prior to and after the application of selected retrofitting schemes, in order to quantify the positive effect that retrofitting could provide to RC buildings both in terms of their structural and energy performance. Advanced materials, namely the textile reinforced mortars (TRM), were used for providing seismic retrofitting by means of jacketing of masonry infills in RC frames. Moreover, following the application of the TRM jackets, thermal insulation materials were simultaneously provided to the RC building envelope, exploiting the fresh mortar used to bind the TRM jackets. In addition to the externally applied insulation material, all the fenestration elements (windows and doors) were replaced with new high energy efficiency ones. Afterwards, an economic measure, namely the expected annual loss (EAL) was used to evaluate the efficiency of each retrofitting method, but also to assess whether the combined seismic and energy retrofitting is economically feasible. From the results of this preliminary study, it was concluded that the selected seismic retrofitting technique can indeed enhance significantly the structural behaviour of an existing RC building and lower its EAL related to earthquake risks. Finally, it was found that the combined seismic and energy upgrading is economically more efficient than a sole energy or seismic retrofitting scenario for seismic areas of south Europe.JRC.E.4-Safety and Security of Building

Tensile characterization of multi-ply fabric-reinforced cementitious matrix strengthening systems

Fabric reinforced cementitious matrix (FRCM) is a composite consisted of high-strength fibers impregnated in a cement-based mortar, and is commonly used for strengthening reinforced concrete and masonry structures. Comprehending the tensile behavior of FRCM is important to achieve a reliable and accurate design of FRCM strengthening systems. The current paper reports on the results of an experimental study on the tensile characterization of FRCM. A total of 40 FRCM specimens (410 50 mm, varied in thickness) were prepared and tested. The tensile characterization tests were conducted according to AC 434 guidelines using clevis-grip mechanism. The tests were used to assess the effect of two parameters: (a) fabric type (carbon/glass) and (b) number of fabric plies (one/two/three/four). The results showed that the tensile strength of carbon-FRCM specimens was approximately 1.33 times that of the glass-FRCM counterparts. Three distinct failure modes were observed, namely, (a) ductile fabric slippage in carbon-FRCM (up to three plies of fabric); (b) brittle fabric delamination in carbon-FRCM with four plies of fabric; and (c) brittle fabric rupture in glass-FRCM systems. The FRCM tensile load-carrying capacity had proportionally increased with the number of fabric plies; less significant effect (within 20%) was observed on the corresponding ultimate tensile stresses (considering the net fabric area as the effective area).Qatar University, Qatar National Research Fund, Qatar FoundationScopu

Enabling Flexibility in Manufacturing by Integrating Shopfloor and Process Perception for Mobile Robot Workers

Robotic flexibility in industry is becoming more and more relevant nowadays, especially with the rise of the Industry 4.0 concept. This paper presents a smart execution control framework for enabling the autonomous operation of flexible mobile robot workers. These robot resources are able to autonomously navigate the shopfloor, undertaking multiple operations while acting as assistants to human operators. To enable this autonomous behavior, the proposed framework integrates robot perception functions for the real-time shopfloor and process understanding while orchestrating the process execution. A Digital World Model is deployed synthesizing the sensor data coming from multiple 2D and 3D sensors from the shopfloor. This model is consumed for the perception functions enabling the real-time shopfloor and process perception by the robot workers. This smart control system has been applied and validated in a case study from the automotive sector