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Large-diameter bored piles can safely transmit loads from structures by skin friction to the surrounding soil strata and end bearing at the bedrock layer, thereby providing a high compressive capacity. High-Strain Dynamic Testing (HSDT) provides a unique alternative technique to traditional Static Load Testing (SLT) for determining the static compressive resistance of the bored piles, considering its quicker performance and significant cost reductions. This article's main objective is to numerically explore the performance of large-diameter bored piles during the HSDT and to understand their dynamic behavior under an axial compressive impact force. This research is based on testing pile foundations for reinforced concrete mixed-use towers in the coastal zone of New Alamein City, Egypt. The tested pile is a 1.20 m diameter bored pile. Numerical modeling is performed to simulate both the HSDT and the SLT for two piles at the same site. Non-linear axisymmetric finite element modeling is employed to validate both test records and develop some sort of matching between the two tests. As lumped models, the developed numerical models use the signal-matching process, which is conducted by varying and adopting the strength parameters and deformation characteristics of the ground or soil deposit and the soil–pile interface. The predicted load-displacement curves, developed from analyzing dynamic records employing the Modified Unloading Point (MUP) method, are consistent with the field records. The verified non-linear models are utilized to accomplish a comparative parametric analysis to better understand the drop-mass system aspects. The analysis results emphasize the significance of employing adequate impact energy (i.e., dropping height and mass) to move the pile top to a sufficient extent to mobilize its full resistance. However, a longer impact duration, i.e., larger mass, is more effective for achieving a deeper high-strain wave. The impact load should be developed by a larger drop mass with a lower drop height, not a smaller drop mass with a higher drop height. The results also indicate that, for relatively longer piles, the skin friction of the upper layers surrounding the pile shaft is fully mobilized, whereas the skin resistance of the lower layers is not fully mobilized, regarding the stress wave phenomenon effect. Finally, this study's findings can be employed to develop guidelines and design procedures for the HSDT to be effectively performed on bored piles. [ABSTRACT FROM AUTHOR]

The use of Ultra-High Performance Fiber Reinforced Concrete (UHPFRC) increased in the field of civil engineering throughout the last few decades. UHPFRC is being used considerably on a large scale in megastructure applications. High compressive and tensile strength permits reconstruction and optimization of the structural members. At the same time, its improved durability properties make it easier to extend the life of the design and can be used as thin layers, cladding, repairs, and column coverings. Although UHPC has an extremely high compressive strength, it exhibits very brittle fracture behavior compared to normal strength concrete (NSC). Since the ductility and fracture toughness of UHPC can be enhanced by adding fibers, the addition of fibers to production adds innovative features to UHPFRC structures and opens up new application areas for UHPFRC. The aim of this study is to investigate the axial behavior of square reinforced concrete (RC) columns strengthened with UHPFRC jackets. Nineteen specimens were cast (1000 mm in height and a cross-sectional area of 150 × 150 mm, whose interface treatment methods were prepared through vertical grooving (VG), horizontal grooving (HG), and without grooving (NG), with the jacket thickness (20 mm and 40 mm) and the number of strengthened sides of the column (two, three, and four sides). The results show a brittle failure for all strengthened specimens. The UHPFRC-reinforced RC columns with vertical grooving (VG) showed a higher ultimate load capacity compared to the columns with horizontal grooving (HG) and the columns without grooving (NG). The horizontal grooving (HG) gives a better result than the jacket without grooving (NG) and increases the cohesion area between the jacket and the column for two and three of the RC columns' strengthened sides. But, in the case of strengthening the columns on four sides, the effect of confining the jacket to the column appears, and the grooving causes weakness in the body of the original column so that the jacket without grooving (NG) gives a better result than the jacket with horizontal grooving (HG). [ABSTRACT FROM AUTHOR]

This paper presents a detailed analysis of the research into modern thermal energy storage systems dedicated to autonomous buildings. The paper systematises the current state of knowledge concerning thermal energy storage systems and their use of either phase change materials or sorption systems; it notes their benefits, drawbacks, application options, and potential directions for future development. The rapid proliferation of studies on installation systems, new composites, and phase change materials requires a systematisation of the subject related to short- and long-term thermal energy storage in building structures. This paper focuses on assessing the validity of the current improved thermal energy storage solutions for buildings with very high energy efficiency standards and buildings that are energy-independent. The paper presents the current results of the energy and economic analyses of the use of heat storage systems in buildings. This paper shows the optimal heat storage systems for autonomous buildings. Moreover, it also shows other potential ways to develop systems and composites capable of storing heat in autonomous buildings. [ABSTRACT FROM AUTHOR]

In this study, hybrid nonlinear finite element models (FEM) were developed to examine the flexural performance and the ultimate load capacity of bonded and unbonded two-way reinforced concrete post-tensioned (PT) slabs that were pre-strengthened with external carbon-fiber reinforcement polymer (CFRP) laminates. Full 3D simulations, using ANSYS models, have been created for five different slab samples that were selected from a previously available experimental study. The model results were assessed to enable further numerical analysis. The result calibration included measurements of first crack loads, ultimate loads, deflections, strains in the extreme fiber of concrete, strains in CFRP laminates, and failure modes. The results proved a good correlation between FEM output and experimental ones. Based on this, the influencing parameters that affect plate stiffness, as well as the bending capacity of PT slabs, were examined by performing a detailed parametric study. The parameters included real-life load simulation, cable-to-CFRP strength contribution, and CFRP laminate location selection. The results demonstrated that strengthening using CFRP laminates have significantly increased the ductility index of both bonded and unbonded PT concrete slabs by 62.18% and 59.87%, respectively. In addition, strip strengthening locations near supports are much more effective than in the middle of slabs. Additionally, the CFRP strengthening contribution is very considerable in slabs with low PT ratios. [ABSTRACT FROM AUTHOR]

The classroom space located in the attic of an old building is the subject of this study. The building was renovated and new spaces were created in the unused attic to expand classrooms. The original space under the sloping roof was not used because its internal headroom was not suitable. During the restoration, the entire original truss was raised gradually (in parts) by 1.2 m. This created a space with an entire area that can be used for classrooms. Continuous strips of vertical windows measuring 860/600 mm were installed in the space which enable a visual connection between the interior space and the exterior. At roof level, there are also two rows of skylights above each other which ensure enough daylight is present but create unpleasant overheating in the summer. The purpose of this study is to find a way to optimize the shading of transparent surfaces and the heat accumulation of building structures in order to achieve suitable interior conditions in the attic. This task was achieved by shading the windows in the attic. Shaded windows decrease illumination by 82% compared to unshaded ones. The percentage decrease in illumination is more significant than the decrease in the maximum temperature due to overheating. Additionally, the maximum temperature in the attic drops by only 31% if vertical and skylight windows are shaded with external blinds compared to unshaded windows. The minimum air temperature reached in the attic also drops by 26%. In order for users in the attic space to feel comfortable, it is necessary to use HVAC equipment in addition to the design of suitably built structures and window shading. [ABSTRACT FROM AUTHOR]

The adoption of green building technology has become significant for ensuring sustainable development; it has become the main step to a sustainable future. The designs for green buildings include finding a balance between comfortable home construction and a sustainable environment. Moreover, the application of emerging technology is also used to supplement existing methods in the development of greener buildings to preserve a sustainable built environment. The main problem of this research is how to tackle the environmental parameters balance based on new techniques that are being used for green building optimization. To mitigate the cumulative effect of the constructed climate on human wellbeing and the regular ecosystem, the most popular goals for green buildings should be planned. This can be achieved by efficient use of natural resources such as energy, water, and other resources and minimizing waste. This will contribute to the security of occupant health, enhancement of work performance, emissions control, and improvement of the environment. In the construction of green buildings, several criteria that may contradict, interrelated indistinct and of qualitative and/or quantitative environment are broadened to utilize. This paper provides a detailed state of the art analysis on improving existing practices in green architecture/building using analytical hierarchy process (AHP) techniques to tackle the environmental balancing values based on optimal strategies and designs by green solutions to help make the best possible option from numerous options. [ABSTRACT FROM AUTHOR]

The main goal of this paper is to evaluate the effect of color changes on the interior surfaces of a selected hall on the level of daylight, represented by the DF factor. A single-story hall was chosen as the reference building, in which daylight falls through the side windows and a skylight at roof level. Measurement of the level of daylight in the real state of the building (in situ) was carried out. The measurement took place when the external boundary conditions of the measurement were met (external state of the sky). A survey was conducted among users, in which they considered the visual perception of the environment and what colors would be suitable for the walls, ceiling, and floor in the working environment of the hall. The evaluation of the respondents who considered the color of the floor was interesting, and several agreed that the floor should be brown. After debugging the model for the simulation based on the actual state of the measurement, simulation calculations were performed with selected surface colors in the interior of the hall. Computational simulations were performed for changing calculation boundary conditions. Daylight Factors (DF) (%) were evaluated, namely minimum, maximum, and average DF values for 15 selected simulations. The calculations were performed in the RADIANCE simulation program. Simulations included the change in the surface color of the simulated wall and the current ceiling surface color, the color of the simulated ceiling surface and the current wall surface color, and the color of the simulated wall and ceiling at the same time. The floor color did not change during the evaluation; it was considered brown. Based on the evaluation of AHP, evaluations of the significance and comparability of colored areas were performed. The value of the average DF was chosen as the most important, the less significant minimum DF value was chosen, and the maximum DF value was considered in the last place. The results show that white, gray, green, or yellow walls, white ceiling, and brown floor were rated as the most suitable for the interior surfaces in the considered hall. [ABSTRACT FROM AUTHOR]

In the climate change era, the tendency to utilize computer-aided strategies in architectural design enables the incorporation of the influences of ambient conditions into the design process. Such a design strategy can consequently contribute to creating nature-based, sustainable architectural, and urban solutions. In this paper, it will be shown that the built environment can be designed, already from the first concepts, to affect and consequentially improve the local wind microclimate by addressing the unfavorable wind effects and proposing solutions for transforming them into an advantage. Utilizing the iterative Research Through Design (RTD) approach, the proposed data-driven wind-oriented shape optimization is introduced in a case study located in Stockholm. Three complex architectural shapes, resulting from the wind-oriented design approach, are parametrically designed in Grasshopper for Rhino and subsequently analyzed in a Computational Fluid Dynamics (CFD) plug-in Swift for Grasshopper. [ABSTRACT FROM AUTHOR]

This paper highlights the problems that are associated with daylight use in industrial facilities. In a case study of a multi-story textile factory, we report how to evaluate daylight (as part of integral light) in the production halls marked F and G. This study follows the article in the Buildings journal, where Hall E was evaluated (unilateral daylight). These two additional halls have large areas that are 54 x 54m and are more than five meters high. The daylight is only on the side through the attached windows in envelope structures in the vertical position on the hall. In this paper, we want to present two case studies of these two production halls in a textile factory in the eastern part of Slovakia. These are halls that are illuminated by daylight fromtwo sides through exterior peripheral walls that are against or next to each other. The results of the case studies can be applied in similar production halls illuminated by a "double-sided" (bilateral) daylight system. This means that they are illuminated by natural illumination through windows on two sides in a vertical position. Such a situation is typical for multi-storied industrial buildings. The proposed approximate calculation method for the daylight factor can be used to predict the daylight in similar spaces in other similar buildings. [ABSTRACT FROM AUTHOR]

We present observations from evaluation of internal environmental quality of industrial halls with priority on daylighting in combination with the integral lighting. The physical parameters related to indoor lighting in large industrial halls in winter and summer periods were analyzed using in situ measurements and computational methods. These are part of a comprehensive research on indoor environmental quality of industrial halls with the aims of saving energy and providing a comfortable environment for the workers while improving the productivity. The results showed that the procedures used for evaluation of residential or office buildings may not be used for industrial buildings. We also observed that the criteria of occupants' comforts for indoor industrial buildings may differ from those of other kinds of buildings. Based on these results, an adequate attention is required for designing the industrial buildings. For this reason, appropriate evaluation methods and criteria should be created. We found the measured values of daylight factor very close to the skylight component of the total illumination. The skylight component was observed on average 30% that of the measured daylight factor values. Although the daylight is not emphasized when designing the industrial buildings and its contribution is small, but it is very important for the workers psychology and physiology. The workers must feel a connection with the exterior environment; otherwise, their productivity decreases. [ABSTRACT FROM AUTHOR]

An important parameter that affects indoor climate of buildings and also ventilation heat losses and gains is the speed of air change between the outdoor environment and the interior of buildings. Indoor air quality is therefore significantly associated with ventilation. Quantification of air change rate is complicated, because it is impacted by many parameters, the most variable of which is air flow. This study focuses on the determination and comparison of air change rate values in two methods by quantification of the aerodynamic coefficient Cp = Cpe − Cpi, so-called "aerodynamic quantification of the building" and the methodology based on "experimental measurements of carbon dioxide". The study describes and takes into account the effect of wind, building parameters and air permeability for the building using "aerodynamic quantification of the building". The paper compares these calculated results with the values obtained from experimental measurements method of carbon dioxide in a selected reference room in apartment building and evaluates the accuracy of the prediction of the air exchange rate obtained by these methods. At higher wind speeds the values of air change rate with considering the effect of openings are closer to the values obtained based on experimental measurements of carbon dioxide and the difference between the values without considering the effect of openings increases significantly. [ABSTRACT FROM AUTHOR]

The reconstruction of balconies and loggias is a key element of the renovation of apartment buildings. Artificial light will never replace natural light. Every day, one must make full use of the potential of daylight and enjoy an advantage—free-of-charge natural light entering the interior. When renovating balconies, people often change the character of this protruding structure from a façade to a loggia. This is also the subject of this paper. For the evaluation of the daylighting conditions prevailing in residential building, the Daylight Factor (DF) was considered as the parameter for indicating the quantity of admitted daylight. The DF values and illuminance—CIE overcast sky were calculated using DIALux 9.1 software. The aim of the paper is to compare two variants of the level of daylight in the rooms of the residential building. One option to bring in even more natural light than a window is a variant with balconies. Loggias are satisfactory in terms of static and thermal technology, but daylight conditions are deteriorating. The article provides an insight into the solution of the renovation of balconies and loggias in a specific apartment building. The result shows their influence on changes in the conditions of natural daylight in the interior of two selected rooms. [ABSTRACT FROM AUTHOR]

The energy consumption of buildings accounts for 22% of total global energy use and 13% of global greenhouse gas emissions. In this context, this study aims to evaluate the energy, economic, and environmental performance of housing in Chile built according to the Passivhaus (PH) standard. The standard was applied to housing in eight representative climate zones with a single-family residence as reference. The analysis incorporated passive strategies, which are considered as pillars of the PH. The energy performance was analyzed using the Passive House Planning Package software (PHPP), version 9.6a. The results showed that when every passive strategy is implemented, the heating energy demand decreases by 93%, while the refrigeration demand is nonexistent. These results were achieved through a 37% increase in the overall initial budget investment, which will be amortized over an 11-year period. In this way, the primary energy consumption is reduced by 32% and, correspondingly, CO2 emissions are reduced by 39%. In modern Chile, it is difficult (but not impossible) to incorporate PH. However, governmental programs and aids could represent an initial step. Therefore, this research will help to identify strategies for incorporating PH in Chile, with the aim of improving the energy performance of housing. [ABSTRACT FROM AUTHOR]

The envelope structures of buildings are exposed to heat-humidity conditions. The heat and humidity flow through these structures depends on the boundary conditions of the indoor and outdoor environments. This paper shows different initial conditions for the determination of temperature spread. The aim is to bring certain results of temperature calculated considering the initial conditions. When temperature changes, heat flow also rapidly changes. In certain specific cases, it is necessary to consider the initial conditions of temperature—for example; when transient energy simulations of real buildings are carried out. The reasons as to why it is necessary to consider the initial conditions, are shown in the examples of one-layer assemblies. The test walls exposed to the transient hygrothermal conditions are placed in the outdoor test cell. The cell has a stable temperature and relative humidity, and outdoor weather conditions change. The measured data on these walls and the calculated values of the temperatures in the wall structure, according to the different initial conditions, are compared. The average difference of the mean by the simulation and the measured values is significant. For a simulation time of about five days, the initial condition for calculating the temperature in the center of the masonry is necessary. [ABSTRACT FROM AUTHOR]

Over the past few decades, digital tools have become indispensable in the field of architecture. The complex design tasks that make up architectural design methods benefit from utilizing advanced simulation software and, consequently, design solutions have become more nature-adapted and site-specific. Computer simulations and performance-oriented design enable us to address global challenges, such as climate change, in the preliminary conceptual design phase. In this paper, an innovative architectural design method is introduced. This method consists of the following: (1) an analysis of the local microclimate, specifically the wind situation; (2) the parametric shape generation of the airport terminal incorporating wind as a form-finding factor; (3) Computational Fluid Dynamics (CFD) analysis; and (4) wind-performance studies of various shapes and designs. A combination of programs, such as Rhinoceros (Rhino), and open-source plug-ins, such as Grasshopper and Swift, along with the post-processing software Paraview, are utilized for the wind-performance evaluation of a case study airport terminal in Reykjavik, Iceland. The objective of this wind-performance evaluation is to enhance the local wind situation and, by employing the proposed architectural shape, to regulate the wind pattern to find the optimal wind flow around the designed building. By utilizing the aforementioned software, or other open-source software, the proposed method can be easily integrated into regular architectural practice. [ABSTRACT FROM AUTHOR]