Effect of retrofit interventions on seismic fragility of Italian residential masonry buildings

In this paper, the vulnerability of ordinary unreinforced masonry (URM) buildings is analyzed, and the literature related to possible seismic retrofit interventions is reviewed in order to investigate their feasibility and effectiveness. These interventions are then simulated on a data-base of 445 buildings through Vulnus_4.0 software, that performs simplified mechanical analyses accounting for both global and local behavior of masonry buildings. The fragility of each building is assessed both in its as-built state and after the simulation of retrofit interventions. Fragility curves are then processed, and a fragility model for four building typologies is obtained for the as -built and the seismic retrofitted configurations. Lastly, mean damage maps are elaborated, and the performance of the proposed retrofit interventions is analyzed. The results of this work allow evaluating and comparing the improvement of seismic behavior brought by various retrofit in-terventions and could serve as a basis for further theoretical studies and for practical design in real cases

Structural assessment of Companhia Aurífícia, a 19th century industrial building located in northern Portugal

Companhia Aurifícia is located in Porto, Portugal, and was founded in 1864. It was a pioneer factory in the industrial production, casting, rolling and stamping of metallic objects and laboured for about 150 years, in areas as jewellery, manufacture of parts in silver and gold or the production and casting of various metals. In 1866, it began labouring in Rua dos Bragas, its present location, and in 2003 ceased all activities. Companhia Aurifícia is an industrial complex including several buildings, all located in the same block. It is a precious example of the industrial architecture in Porto, where the still existent retaining walls, structures, machinery and decorative elements, make it one of the last examples of nineteenth century industrial life of the city. The present work aims to evaluate the safety condition of one of the buildings included in this industrial complex, in order to propose the necessary strengthening interventions

Rehabilitation of the Roof Timber Trusses of a Multiuse Pavilion

This paper describes the rehabilitation procedure of the roof timber structure of a multiuse pavilion in Viseu, Portugal. The roof structure consists of a series of parallel double timber trusses, partially concealed above a polyhedral wooden plank-made ceiling. Recently, the support of one of the trusses failed and another one has been assessed as in a pre-failure condition. Some load-redistribution and the prompt shore of the structure prevented the generalized collapse. The subsequent inspection and assessment led to the conclusion that the primary cause of the collapse was the failure perpendicular to the grain of the solid timber elements inserted between the double rafters and tie-beams. The replacement of the existing with a steel structure, and the repair and reinforcement of the existing wooden trusses, were considered as intervention possibilities. The latter revealed much cheaper, less time-consuming and in line with the international recommendations on rehabilitation works, and was therefore adopted. An innovative solution, consisting of the replacement of the central timber elements in all the supports, resulted in minimum visual impact and improved the load bearing capability beyond its original value. Doi: 10.28991/cej-2020-03091628 Full Text: PD

Wooden Reinforcement for Earth Constructions in the Castile Area of Spain

This chapter studies wooden reinforcements for earth constructions. Analysing vernacular houses from Castile, Spain, I discovered this reinforcement and started to compare its performance with other traditional bracings for earth construction. At present, approximately over 30% of the world’s population still live in earth houses, 50% of which are in the third world countries. This is why it is so important to understand how earthwork constructions behave. Most importantly, for the rehabilitation and preservation of existing World Heritage Sites, also there is a great need to construct new buildings in developed countries under the criteria of sustainability and developing countries because of housing shortages and lack of materials. The main failure of earth constructions is because of the low tensile resistance of the earth, causing walls to detach in the corners under horizontal loads. This chapter analyses a vernacular wooden reinforcement from Castile, Spain: its history, composition, construction and structural behaviour. It compares it with earth constructions without reinforcements, using a unique model under the same conditions. This makes a qualitative and quantitative comparison possible. The conclusions can be applied to rehabilitation or construction of new-build depending on the loads, distances and height, which can be a security condition or a vital necessity

REHAP Balance Tiles: A modular system supporting balance rehabilitation

© 2015 ICST. This paper describes the design, development, implementation and user evaluation of an interactive modular tile system, aimed to support balance rehabilitation of patients recovering from a stroke. The REHAP Balance Tiles system is an innovative tool, which has been developed in close collaboration with therapists and patients in stroke units of health rehabilitation institutes in Sydney, Australia and Eindhoven, the Netherlands. The system was designed to allow therapists to tailor exercises for each patient by changing the physical configuration of tiles. We report a user evaluation in a rehabilitation clinic, which lasted five weeks. Results indicate that the tiles can fulfill their envisioned purpose. They are received well by therapists, meeting requirements for ease of use, motivational feedback, modularity and flexibility

Toward a fast and accurate modeling strategy for thermal management in air-cooled data centers

Computational fluid dynamics (CFD) has become a popular tool compared to experimental measurement for thermal management in data centers. However, it is very time-consuming and resource-intensive when used to model large-scale data centers, and may not be ready for real-time thermal monitoring. In this thesis, the two main goals are first to develop rapid flow simulation to reduce the computing time while maintaining good accuracy, and second, to develop a whole building energy simulation (BES) strategy for data center modeling. To achieve this end, hybrid modeling and model training methodologies are investigated for rapid flow simulation, and a multi-zone model is proposed for BES. In the scope of hybrid modeling, two methods are proposed, i.e., the hybrid zero/two-equation turbulence model utilizing the zone partitioning technique and a combination of turbulence and floor tile models for the development of the composite performance index. It shows that the zero-equation coupled with either body force and modified body force tile models have the best potential in reducing the computing time, while preserving reasonable accuracy. The hybrid zero/two-equation method cuts down the computing time in half compared to the traditional practice of using only two-equation model. In the scope of model training, reduced order method via proper orthogonal decomposition (POD) and response surface methodology (RSM) are comprehensively studied for data center modeling. Both methods can quickly reconstruct the data center thermal profile and retain good accuracy. The RSM method especially shows numerous advantages in several optimization studies of data centers. Whether it is for the tile selection to control the server rack temperature difference or impacting the decision for the input design parameters in the early stage of data center infrastructure design, RSM can replace the costly experiments and the time-consuming and resource-intensive CFD simulations. Finally, for the whole BES study, the proposed multi-zone model is found to be much more effective compared to the common use single zone model. The location factor plays an important role in deciding whether some of boundary conditions are affecting the cooling electricity consumption. In addition, the effect of supply temperature and volumetric flow rate have significant effects on the energy consumption

Energy, Environmental Impact and Indoor Environmental Quality of Add-Ons in Buildings

On a European scale, the existing building stock has poor energy performance and partic-ularly vulnerable structures. Indeed, most of the existing buildings were built before the introduction of energy standards and under structural safety criteria different from those currently required. It is therefore necessary the intervention in existing buildings according to an integrated approach that contemplates both the structural safety and the energy efficiency of buildings. This study, con-sistently with the objectives of the European research project “Proactive synergy of integrated Efficient Technologies on buildings’ Envelopes (Pro-GET-OnE)”, proposes a retrofit intervention for a student dormitory of the National and Kapodistrian University of Athens. The scope of the evaluation is to understand how an integrated intervention, that implies a structural and energy retrofit, as well as a spatial redistribution, leads to an improvement of the Indoor Environmental Quality (IEQ). In detail, the structural retrofit was performed through exoskeleton that leads to the addition of new living spaces and to a remodeling of the building facades. The energy retrofit regarded all three levers of energy efficiency, and thus the building envelope, the microclimatic control systems, and the systems from renewable sources. The integrated intervention, in addition to a reduction of energy demand, has led to advantages in terms of IEQ. Thermal comfort, both during summer and winter, is improved and the hours of suitable CO2 concentration pass from 34% in the pre-retrofit stage up to 100% in the post retrofit stage

Thermally Aware, Energy-Based Techniques for Improving Data Center Energy Efficiency

This work investigates the practical implementation of so-called thermally aware, energy optimized load placement in air-cooled, raised floor data centers to reduce the overall energy consumption, while maintaining the reliability of the IT equipment. The work takes a systematic approach to modeling the data center\u27s airflow, thermodynamic and heat transfer characteristics - beginning with simplified, physics-inspired models and eventually developing a high-fidelity, experimentally validated thermo-hydraulic model of the data center\u27s cooling and power infrastructure. The simplified analysis was able to highlight the importance of considering the trade-off between low air supply temperature and increased airflow rate, as well as the deleterious effect of temperature non-uniformity at the inlet of the racks on the data center\u27s cooling infrastructure power consumption. The analysis enabled the development of a novel approach to reducing the energy consumption in enclosed aisle data centers using bypass recirculation. The development and experimental validation of a high-fidelity thermo-hydraulic model proceeded using the insights gained from the simple analysis. Using these tools, the study of optimum load placement is undertaken using computational fluid dynamics as the primary tool for analyzing the complex airflow and temperature patterns in the data center and is used to develop a rich dataset for the development of a reduced order model using proper orthogonal decomposition. The outcome of this work is the development of a robust set of rules that facilitate the energy efficient placement of the IT load amongst the operating servers in the data center and operation of the cooling infrastructure. The approach uses real-time temperature measurements at the inlet of the racks to remove IT load from the servers with the warmest inlet temperature (or add load to the servers with the coldest inlet temperature). These strategies are compared to conventional load placement techniques and show superior performance by considering the holistic optimization of the data center and cooling infrastructure for a range of data center IT utilization levels, operating strategies and ambient conditions

Fifth International Conference on SALT WEATHERING OF BUILDINGS AND STONE SCULPTURES:

These proceedings report on the 5th edition of the conference, after Copenhagen (2008), Cyprus (2011), Brussel (2014) and Potsdam (2017), and it is the first time the conference is held in hybrid form, due to the COVID-19 pandemic. It is a challenge to organize an event in such an uncertain situation and to make it as attractive and interactive as the previous editions. We hope to meet your expectations! I’m very glad, that despite the situation, the interest for the conference is strong: we have received more than 40 contributions from 18 countries from all over the world. This confirms the relevance of the problem of salt weathering for the built cultural heritage and stone artifacts in a wide range of environments. Moreover, the broad spectrum of approaches to the subject presented in these proceedings highlights the importance of the interaction between different disciplines as well as between fundamental research and practice of conservation. I wish this conference to contribute to this fruitful exchange, and to generate new research ideas, whilst strengthening and broadening interdisciplinary collaborations. On behalf of the organizing committee, I’m looking forward to welcoming as many as possible of you in Delft. We hope that, next to participation to the conference, you will find some free time to visit the city. You can stroll along the canals, enter a windmill, visit the Prinsenhof museum and the Blue Delft Factory, admire the architecture and sculptures in the Old and New Church and, if you are looking for a real Dutch experience, you can rent a bicycle and visit the surroundings! This event would not have been possible without the collaboration of several persons. I would like to thank, on behalf of us all, the Scientific Committee for carefully reviewing the papers and contributing thereby to the high quality of the published contributions. My personal thank goes to the organizing committee who significantly contributed to the organization of this event and to the preparation of the proceedings. Last but not least, I’d like to thank the Cultural Heritage Agency of the Netherlands for co-sponsoring the event and RILEM (International Union of Laboratories and Experts in Construction Materials, Systems and Structures) for contributing to the dissemination