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The design trend of most commercial and office buildings over the past three decades focused on attaining a façade design with the highest possible window to wall ratio. Whereas this approach appears to satisfy the aesthetic scope of developing buildings that look ‘modern and transparent’ to maximise on real estate value, the demand for heating and cooling of these buildings tends to fall short of what one should expect. Literature review shows the possible benefits of switchable glass. This paper proposes a methodology for a novel switchable glazing assembly identified as having the potential of offering increased occupant comfort, particularly in providing sufficient daylight and glare control without diminishing the view quality. The hypothesis is that switchable glazing may have a substantial potential to achieve lower cooling loads and improved indoor visual comfort without compromising views and a positive outlook., Architectural Technology

Patterned acid-etched glasses are frequently used in horizontal glass surfaces that may be walked on, such as floors and staircase treads. These glasses provide useful antislip properties, but the foot traffic cause contact stresses and ageing mechanisms that are poorly understood and can affect the strength of the acid-etched glass. This study explores these strength-reducing effects by undertaking nondestructive and destructive evaluations of two acid-etched glasses with geometrically different surface patterns and comparing their mechanical performance to unetched float glass. In particular, residual surface stress, Hertzian fracture resistance, and fractographic characteristics are determined for each glass type. The surface tensile strength of the glasses is also evaluated by means of destructive flexural tests before and after artificial ageing. The flexural tests reveal that the ridge areas of the acid-etched surface patterns are more susceptible to the formation of digs and deeper surface flaws and are therefore weaker than both the valley areas of the acid-etched pattern and the surface of the unetched float glass. Correspondingly, the acid-etched glass with the highest proportion of ridges was more susceptible to ageing-induced flaws and had the lowest surface tensile strength. The contact (Hertzian) fracture resistance was also significantly affected by the presence of a surface pattern in the acid-etched glass; specifically, the lowest contact strengths were recorded for hard body contact on the ridges of the pattern. The fracture phenomena and new data presented in this paper provide useful insights on the long-term performance of etched patterned glass. The findings can provide the bases for real-world design decisions and for glass forensics., Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care. Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Architectural Technology

The applications of architectural and automotive laminated glass continue to grow. This is largely due to the enhanced safety in extreme events, such as blast. However, the complex interaction between the glass fragments and the polymer interlayer after glass fracture is still only partially understood, with existing analysis methods adopting a semi-empirical approach for the post-fracture response. These include a plastic yield-line analysis based on a failure pattern repeatedly observed during blast tests. In recent research it was demonstrated that yield lines can develop in fractured laminated glass through the composite bending action of the glass fragments, working in compression, together with the interlayer working in tension. This paper investigates the influence of the inertia loading associated with blast response, which has not been explicitly studied previously, with the aim of understanding the pattern of yield lines observed in blast tests. Impact tests are performed on laminated glass specimens using foam projectiles launched from a gas gun, which simulate the loading from a blast pulse. These tests demonstrate that the yield line pattern formed under short-duration dynamic loading depends on the loading intensity, thereby providing further evidence of a dynamic, plastic collapse mechanism in which inertia plays a significant role., Architectural Technology

The building sector has gained significant attention due to its remarkably high energy consumption and greenhouse gas emissions. In China's rural areas, stone is a popular building material, but there are unprecedented demands to improve the life-cycle performance of stone buildings. It is essential to preserve the original architectural features while evolving towards a cleaner production and operation. This study implements a field survey in the Taihang Mountains of Hebei province. The improvement of stone extraction methods and the evolution of three stone wall styles are collected and developed. Thermal transmittances of three stone walls are measured and modeled. A cradle-to-grave life cycle assessment is conducted, and the results are compared to show their environmental performance in the embodiment and operation phases. Their life cycle inventories, including stone extraction, are developed. One representative building style sample is developed for the cooling and heating energy requirement simulation in the DesignBuilder. Based on the inventories, conducting life cycle impact assessment shows various environmental profiles in their whole life cycles. From the outcomes, the stone cladding wall (SCW) outperforms the other stone walls in both the embodiment and operation phases. However, its relatively high cost is a challenge for an individual house owner. This study proves the SCW is more sustainable, providing a basis for the choice of stone wall style in the future construction., Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Architectural Technology

High-performance glazing technologies are essential for achieving the occupant comfort and building energy efficiency required in contemporary and future buildings. In real-world applications, glazing façades are selected from a steadily increasing number of glazing technologies. However, the authors could not identify a systematic and comprehensive review and classification of glazing technologies in the literature. This creates a barrier when comparing typologically different glazing technologies and combining multiple technologies in a glazing unit. This paper provides a systematic review and classification of established and emerging glazing technologies based on publications from 2001–2022 which were interpreted following the PRISMA methodology. This study reveals that the majority of high-performance glazing systems used in practice are in multi-layer glazing configurations and that the glazing system performance can focus on including additional and multiple functionalities, which aim at improving overall building performance. It was also found that there is a large potential for improvement of multilayer, evacuated, aerogels, electrochromic, and solar cell glazing by incorporating other technologies or innovative materials in multi-layer glazing units for either improving existing technologies or for the development of new ones. However, their longevity, robustness, and cost affordability should be ensured., Architectural Technology

Applied Mechanics, Architectural Technology

This article has been amended to correct the in-text figure and table referencing and to provide clarification in Table 1 that automotive flat glass production does not take place in the UK. The Supplementary Information has been updated to correct reported units and clarify production processes. The original article has been corrected., Architectural Technology

Since the beginning of 2021, CEN/TS 19100 Design of Glass Structures has been available in its first three parts. The fourth part is expected soon. This Technical Specification of the European standards organisation CEN is as a pre-standard of a corresponding future Eurocode. These documents constitute the first ever comprehensive design code for the entire structural glass engineering field on the European market for the first time. In addition to a clear outline, the Technical Specification has been drafted to be compatible with EN 1990 “Basis of Design” and to address glass-specific design matters, particularly related to robustness and redundancy. Although the standard still has the status of a CEN/TS, thereby allowing the European nations the option of whether to introduce it, either in full or in parts, it already contains national openings through which the European countries can adapt the design results to their own safety level by National Determined Parameters (NDPs). Such an approach already anticipates the future Eurocode, which is expected to be published as EN 19100—Design of Glass Structures. This article provides some context on the history and concept behind the new documents and gives an overview of the design rules and the corresponding technical background of the different parts of CEN/TS 19100., Applied Mechanics, Architectural Technology

Occupant satisfaction and acceptance with automated control strategies for dynamic façades is currently a barrier to the upscale of these systems. Building owners, designers and occupants are often unconvinced that an automated control strategy for dynamic façades could really be beneficial for building energy efficiency and occupant satisfaction. Previous work has indicated that an integrated multi-domain approach is required for capturing the influence of façades on occupants. The aim of this paper is to provide new knowledge on whether dynamic automated facades with user override (semi-automated) can outperform manually operated facades in terms of occupant multi-domain satisfaction. Occupant interaction, discomfort, satisfaction and indoor environmental quality were monitored in two different scenarios: one where the façade blinds were automatically controlled, aiming at maximising daylight and outdoor view access whilst mitigating glare, and one in which the façade blinds were manually controlled by the occupants. Results showed that when the façade was controlled by a semi-automated strategy, occupant satisfaction was higher (especially in the thermal environment), despite occupants reported a higher number of discomfort events due to lack of daylight and access to outdoor view. However, to increase occupant acceptance, a better prediction of occupant glare to prevent visual discomfort and maximise daylight and view is necessary., Architectural Technology

Embedded load-bearing laminated glass connections have gained popularity in recent years due to their mechanical performance and aesthetic appeal. However, there is a paucity of data on their structural behaviour across a range of temperatures that may arise in building applications and there is also no simplified mechanics-based model for predicting their load–displacement response. This study addresses these gaps directly through experimental pull-out tests on steel inserts encapsulated in resin-laminated glass performed at various temperatures. The experimental results confirm that the response of the resin interlayer is time / temperature-dependent which therefore significantly affects the connection behaviour. In particular, both the stiffness and strength of the connection decrease with increasing temperature. Similarly, temperature also governs the failure mechanism of the connection. Specifically, temperatures at or below ambient indoor temperature (-10 °C and + 22 ± 2 °C) result in glass fracture whereas at + 50 °C the connection fails due to insert delamination. The numerical (FE) simulations of these tests show that a complex stress/strain state is set up in the vicinity of the embedded insert which correlates well with the experimentally observed failure mechanisms at different working temperatures. Finally, the insights gained along with the data generated from the experimental and numerical work were used to develop a simple analytical tool that predicts the pull-out load–displacement response of the embedded connection at different temperatures and load durations., Structural Design & Mechanics

Applied Mechanics, Architectural Technology

Laminated glass panels are increasingly installed in glazed façades to enhance the blast protection of buildings. These ductile panels offer residual bending resistance following the fracture of the glass layers, due to the composite action of the attached glass fragments in compression and the interlayer in tension. Three-point bending tests performed previously on laminated glass specimens at low temperature, which aimed to simulate the effects of high strain-rate due to the time-temperature dependency of the interlayer, demonstrated an enhancement of the ultimate load capacity by two orders of magnitude compared to that at room temperature. These tests were performed on specimens with an idealised fracture pattern, by pre-fracturing cracks at a uniform spacing of 20 mm, aligned in both glass layers. Under blast loads, however, a random pattern of irregular fragment sizes occurs, with the cracks not always aligned in the two glass layers. Additionally, the plastic hinge location within each specimen coincided with the point of application of the load, which may have influenced the results. This paper addresses these concerns by reporting on further low-temperature tests that have considered four additional pre-fractured patterns in both three- and four-point bending. The results demonstrate that the bending moment capacity of the specimens is unaffected by the number and size of the glass fragments, and by the choice of the loading rig. An enhancement of the bending capacity is consistently observed for specimens with misaligned cracks that is almost twice that of specimens with aligned cracks. This suggests that the idealised pattern with aligned cracks, considered in previous work, results in a lower-bound estimate of the bending capacity for panels with random fracture patterns formed under blast loading., Structural Design & Mechanics

In its simplest form, a Closed Cavity Façade (CCF) consists of a double or triple glazing unit (DGU or TGU) on the inner layer and single glazing on the outer one, forming a sealed non-ventilated cavity with an automated shading device in between. Given its dynamic behaviour, this technology can dynamically control the flow of solar energy and light penetrating the building. Using EnergyPlus and IDA ICE, several CCF configurations were investigated and compared to the baseline (TGU). MATELab, an office-like test facility at the University of Cambridge, was used as the model, which was beforehand experimentally validated. The results show extensive benefits of CCFs compared to traditional TGU systems, in terms of thermal performance and occupants’ comfort. The CCF configurations investigated led to an improvement of energy performance in the range of 18–37% compared to the traditional TGU, depending on the CCF configuration and the climate while a previous study, using CCF configurations with DGU as inner skin, revealed an improvement of energy performance in the range of 22–41% compared to the conventional DGU. Further investigation showed that glass coatings and solar shading characteristics play an important role in cutting down overheating phenomenon while increasing occupants’ comfort. Practical application: Governments are making ever more stringent energy regulations for the building industry aiming to reduce energy consumption and carbon emissions. At the same time, building owners and architects are looking at cost-effective solutions for the long-term performance of buildings while tenants/occupants are more than ever aware of the fact that building comfort increases well-being and productivity. In all these regards, this work focuses and accentuates that substantial improvements can be achieved by designing and using suitable configurations of the innovative Closed Cavity Façade according to the climatic conditions of each location. The results presente, Structural Design & Mechanics

Building occupants interact frequently with façades. These interactions simultaneously affect several domains of the indoor environment (visual, thermal, air quality and acoustic) and occupant perception, as well as the energy performance of the façades. Yet this multi-domain relationship between façade and occupant is not well understood. This gap in knowledge is particularly problematic for dynamic façades, where automated controls endeavour to improve the energy efficiency and reduce occupant dissatisfaction. In particular, it is often unclear whether an integrated multi-domain approach is strictly required when evaluating occupant satisfaction with automated or manual dynamic façades. This research provides a “proof-of-principle” that such an approach is required. This conclusion was drawn after performing. small exploratory campaign conducted in a test chamber designed specifically for occupant-façade interaction in which several human volunteers were exposed to alternative façade typologies (a single-skin façade and a closed cavity façade) and different control strategies (manual control and automated control). As expected, the results show that the effects on the indoor environmental quality, occupant satisfaction and discomfort vary in space and time, and between the façade typologies investigated. It was also found that occupant satisfaction was not only affected by whether a certain thermal or visual condition had been reached, but also on how it had been achieved, e.g. whether the actuation was perceived as disruptive by the occupants. Finally, the results show that occupant satisfaction and the level of interaction in one domain may be affected by satisfaction in other domains., Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Structural Design & Mechanics

Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Applied Mechanics, Structural Design & Mechanics

The thermal performance of adaptive building envelopes can be evaluated using building performance simulation tools. Simulation capabilities and accuracy in predicting the dynamic behaviour of adaptive building envelopes can be enhanced through co-simulation. However, it is unclear how accurately co-simulation can predict the performance of adaptive building envelopes and how the accuracy of adaptive building envelope models created in co-simulation setups can be assessed and validated. Therefore, this study presents new evidence on the empirical validation of co-simulation setups for adaptive building envelopes by establishing an assessment framework to determine the extent to which they can accurately represent the real world. The framework was applied to a case study to validate a co-simulation setup for a blind automation system using monitored data from MATELab, a full-scale outdoor test facility with realistic indoor and outdoor conditions. The validation of the co-simulation model of MATELab resulted in a median CV-RMSE index, a measure of model accuracy, of 5.9%. This indicates that the simulated data points have a small variance relative to the measured data points, showing a good model fit. In the future, modellers from the façade community can use the assessment framework for their co-simulation setups., Architectural Technology, Structural Design & Mechanics

Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Applied Mechanics, Structural Design & Mechanics

Editorial, Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Structural Design & Mechanics, Applied Mechanics

Glass is one of the UK’s eight energy-intensive industries. As such, it is under scrutiny to decouple growth in production from greenhouse gas (GHG) emissions. Recycled glass, also known as cullet, requires less energy to melt than primary raw materials in new glass production. The use of cullet thus reduces the energy intensity per unit of output whilst also reducing demand for primary material resources. However, efficient systems for flat glass collection are yet to be established in the UK, resulting in a limited supply of cullet available for the flat glass market and missed environmental opportunities. This study identifies the existing supply-chain inefficiencies in the UK glass industry in three stages. Firstly, the mass flows of materials within the three main glass sectors: container glass, flat glass and glass wool, are mapped from natural resource through to primary application and subsequent end-of-life management based on a reference year of annual production figures. The map is presented in the form of a “Sankey” diagram which draws attention to several opportunities for increasing resource efficiency; namely in the stark contrast in glass collection rates between the flat and container glass industry. Using the data collected on the annual mass flows of materials in the UK flat glass sub-sector, the energy (MJ) and GHG emission (CO2-eq) saving potential of enhanced end-of-life collection methods are assessed, based on three alternative recovery scenarios. These scenarios consider the use of alternative distributions of recovered flat glass cullet in the three primary glass sub-sectors. The emission savings resulting from each recovery scenario are evaluated, based on the estimated tonnage yield of finished flat glass products. It is shown that together with improved manufacturing yield, the reutilization of end-of-life flat glass as cullet in new production could reduce the annual emissions of the UK flat glass value-chain by up to 18.6, Architectural Technology

This research revolves around the design, fabrication and testing of tubular glass columns, with particular focus on their redundancy and fire-safety mechanisms; moreover, addressing aspects such as: the column shape; cleaning and maintenance; end connections; geometric tolerances in the glass and demountability. Two alternative circular hollow (tube) column designs are initially developed and engineered to address these aspects, namely: the MLA (Multi Layered with Air) and the SLW (Single Layered with water). In both concepts the main load-bearing structure consists of two concentric laminated glass tubes. Thus, in order to explore the manufacturing challenges and structural potential of these concepts, the prototyping and experimental work focuses on six 300 mm long samples with 115 mm outer diameter that are laminated and fitted into customized, engineered steel end-connections. Particular attention in terms of manufacturing is paid to the lamination process and associated bubble formation, the possible fracture of the glass by internal resin-curing stresses and the interface between the glass tube and the steel end-connections. All samples are laminated with Ködistruct LG 2-PU component. Three samples are assembled using DURAN® (annealed) glass and the other three are using DURATAN® (heat-strengthened) glass. Subsequently, the six samples are tested in compression until failure to investigate the behaviour of the interlayer material, the post-fracture behaviour of the designs, the differences between annealed and heat-strengthened samples, the capacity of the glass tubes and the performance of the end connections. Initial cracks appeared between 95-160 kN (compression strength of 30-50 MPa) in the DURAN® samples and between 120-160 kN (compression strength of 37-50 MPa) in the DURATAN® samples. These loads are lower than the ones estimated by calculations; in specific, the first cracks occurred at 34-64% of the calculated load. Nevertheless, the samples are foun, Applied Mechanics, Structural Design & Mechanics

Structural safety and environmental sustainability are major factors in investment decisions for building systems, but are rarely considered simultaneously. Recent research efforts have redressed this by developing assessment methodologies and technical solutions for integrated energy efficiency and seismic performance. These studies are typically limited to existing buildings and retrofit interventions at global building scale, whereas an effective framework could and should be part of the design process of either new or existing buildings at both building and component scales. This paper proposes a probabilistic-based assessment framework to assess the building performance in terms of integrated economic losses and support the selection of resilience-enhanced solutions. The proposed methodology is validated through its application to reinforced concrete case-study buildings consisting of traditional vs low-damage earthquake-resistant technologies coupled with energy efficiency strategies. Seismic and energy risk assessment analyses are performed accounting for both modelling uncertainties and earthquake/weather variability. Probabilistic distributions of the integrated economic losses are finally derived to compare the design solutions in terms of risk and reliability. The research outcomes demonstrate the effectiveness of the probabilistic approach for decision-making in building projects. Specifically, it is found that the economic losses can be highly underestimated (greater than40 %) in the single domains (energy or seismic); greater savings and return on investment can be achieved when the seismic safety is involved in the design process; probabilistic distributions and reliability/risk values can represent an effective tool to assess and compare design solutions., Structural Design & Mechanics

Connections between load-bearing glass components play a major role in terms of the structural integrity and aesthetics of glass applications. Recently, a new type of adhesive connection, known as embedded laminated glass connections, has been developed where a metallic insert is embedded within a laminated glass unit by means of transparent polymeric foil interlayers and assembled through an autoclave lamination process. In this study, a novel variant of this connection, consisting of a thin steel insert encapsulated by a transparent cold-poured resin, is proposed and examined. In particular, the axial tensile mechanical response of this connection is assessed via numerical (FE) analyses and destructive pull-out tests performed on physical prototypes at different displacement rates in order to assess the effect of the strain rate-dependent behaviour of the resin interlayer. It was found that the pull-out stiffness, the maximum load-bearing capacity and the failure mode of the connection are significantly affected by the imposed displacement rate. The numerical (FE) analysis of the pull-out tests, performed in Abaqus, showed that the complex state of stress in the vicinity of the connection is the result of two load-transfer mechanisms and that the relative contribution of these mechanisms depends on the insert geometry and the relative stiffnesses of the constituent materials. Overall, it is concluded that the prototypes are promising in terms of manufacturability, aesthetics and structural performance and thus the novel variant connection considered in this study offers a promising alternative to existing load-bearing connections for laminated glass structures, but further investigations are required to ascertain its suitability for real-world applications., Structural Design & Mechanics

Testing of novel facade technologies with human volunteers is essential for improving occupant interaction with novel dynamic facade systems and to increase satisfaction with its modulation of light, sound, heat and mass transfer between the outdoor and indoor environments. In the past 10 years, there have been noticeable attempts to develop chambers that endeavour to assess the influence of facade technologies on occupant environmental perception and occupant-facade interaction. This paper firstly reviews existing state-of-the-art chambers for occupant-facade interaction and establishes the principal design criteria and performance characteristics required for such facade test chambers. The paper then demonstrates how this information is used to design and construct MATELab, a facade test chamber in Cambridge, UK, devised for capturing occupant environmental perception to, and interaction with, the facade in a realistic, yet sufficiently accurate manner. Finally, results from a preliminary measurement campaign in MATELab are used to validate the experimental setup, in particular its ability to capture high-resolution data for assessing: (i) the influence of facades on Indoor Environmental Quality (IEQ); (ii) occupant environmental perception and interaction with the facade and (iii) do so similarly to typical office spaces. It was found that MATELab can successfully identify the correlations between facade performance and IEQ and that occupant response can be captured with sufficient frequency and in a realistic manner. However, further work is required to improve the experimental setup, in particular, to monitor luminance and direct solar radiation within the indoor space in a non-disruptive, yet experimentally efficient manner., Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Structural Design & Mechanics

Glazing is a critical buildings element as it is the most vulnerable envelope part to heat gain and heat loss accounting for around 50% of a building's energy consumption. However, conventional glazing technologies have relatively low-performance characteristics which cause significant heat losses during winter and undesired heat gain in summer. In this regard, this study investigates the thermal and visual performance of various design configurations of a novel glazing technology, named Closed Cavity Façade (CCF), in comparison with traditional glazing technologies. Several CCF configurations were examined using Energy Plus and IDA ICE and compared to the baseline Double Glazing Unit (DGU) (traditional or thermochromic). MATELab, an office-like test facility at the University of Cambridge was used as the model for the simulations, which was beforehand experimentally validated. The results showed extensive benefits of CCFs compared to DGU systems, in terms of thermal performance and comfort. A 22-41% or 21-37% decrease in annual total energy consumption, compared to traditional DGU or thermochromic respectively, are identified along with a positive effect on thermal comfort with a significant reduction in radiant discomfort. Further investigation showed that glass coatings and solar shading device's characteristics play an important role in achieving further performance improvements., Structural Design & Mechanics

Reuse and high-value recycling have a pivotal role to play in reducing waste and minimising carbon emissions in the built environment. Design strategies for such recovery methods have yet to be fully established in the façade industry. Meanwhile, stringent regulations, aimed at reducing operational carbon emissions of buildings and improving other performance criteria such as occupant safety, have stimulated the use of more complex façade systems that incorporate multiple functions. Other areas of the façade life cycle, such as embodied carbon and high-value material recovery, are rarely considered at the early design stage. This study adopts a mixed-method approach of data collection, to investigate the key challenges and opportunities associated with promoting high-value recovery options for façade products, as perceived by stakeholders in the façade supply-chain. Data was initially collected through an online survey completed by 69 stakeholders from across the façade knowledge/supply-chain. This was followed by 29 semi-structured interviews with selected survey respondents. It emerged that the advancement of circular design strategies is dependent on: increased awareness and quantification of the environmental value of circular design; cross-supply-chain buy-in on developments in take-back infrastructure including greater support for demolition contractors; and advancements in technological separation methods specific to façade components. Enhanced communication between stakeholders - notably between clients, facade contractors and material processors - acceptability criteria and product availability; and more holistic legislation based on whole life cycle emissions, to avoid the over-emphasis on operational efficiency, appear as vital requisites to increasing material efficiency. Finally, we illustrate where stakeholder priorities related to reuse converge and diverge, and thus we identify strategies for levering these factors to minimise environmental impact, Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Structural Design & Mechanics

The design and operation of responsive resource-efficient buildings requires high resolution data in space and time on building performance and the associated occupant response, but capturing this high quality data has traditionally been technologically challenging, costly and disruptive to building occupants. Recent developments in Internet of Things (IoT) technologies provide an opportunity to monitor holistic indoor environmental quality (IEQ) and related occupant perception and behaviour in a more cost-effective and less disruptive manner whilst providing higher granularity data in space and time. Façades have a significant and dynamic influence on IEQ and building performance, and occupants often interact with them, but there is a dearth of IoT solutions for monitoring the façade-induced effects. This paper describes the development, deployment and assessment of the Building Impulse Toolkit (BIT), a prototype IoT system for capturing the holistic and transient influence of façades on IEQ and occupants. The methodology adopted in the design and development of the BIT prototype is first explained. The results obtained from a 9-month deployment in a real-world office are then reported and discussed, in particular the capabilities and limitations of the BIT prototype in: 1) capturing the influence of the façade on IEQ in space and time; 2) monitoring occupant environmental discomfort and satisfaction and in a non-disruptive manner; 3) monitoring occupant interaction with the façade. It was found that BIT is largely successful at meeting these objectives, but occupant engagement could be improved in the next generation prototypes., Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Structural Design & Mechanics

Structural Design & Mechanics, Circuits and Systems

To enhance the resilience of buildings, laminated glass panels are increasingly used in glazed façades. These ductile panels provide a superior blast resistance to that provided by monolithic glass panels, due to the improved residual capacity offered by the polymer interlayer following the fracture of the glass layers. The complex interaction between the attached glass fragments and the interlayer is still only partially understood. To help address this, this paper investigates experimentally the post-fracture bending moment capacity of laminated glass. Three-point bending tests are performed at low temperature on specimens pre-fractured before testing, to ensure controlled and repeatable fracture patterns. The low temperature simulates the effects of the high strain-rates that result from short-duration blast loads by taking advantage of the time–temperature dependency of the viscoelastic interlayer. In these experiments, polyvinyl butyral is considered as the interlayer, this being the most common interlayer for laminated glass used in building facades. A new time–temperature mapping equation is derived from experimental results available in the literature, to relate the temperatures and strain-rates that result in the same interlayer yield stress. The results of the low-temperature tests demonstrate an enhancement of the ultimate load capacity of the fractured glass by two orders of magnitude, compared to that at room temperature. This suggests an improved post-fracture bending moment capacity associated with the now stiffer interlayer working in tension and the glass fragments working in compression. Due to the time–temperature dependency of the interlayer, a similar enhancement is therefore anticipated at the high strain-rates associated with typical blast loading. Finally, the assumed composite bending action is further supported by the results from additional specimens with thicker PVB and glass layers, which result in enhanced capacity consistent with th, Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Structural Design & Mechanics