Discover the Latest Journals in Architecture and Architectonics
Architecture is both the process and product of planning, designing, and constructing a building or structure, while architectonics is the scientific study of architecture itself. Architectural works are often considered important cultural symbols and works of art, and we often identify past civilizations with their architectural heritage.
Architecture and Architectonics
Abstract
The present study aims to determine the effects of blending cementitious materials on the mechanical and durability properties of high-performance concrete (HPC). Densified silica fume and fine-grounded metakaolin are used as supplementary cementitious materials (SCMs). A total of 16 mixes containing both binary and ternary blending of SCMs were chosen for w/b ratios of 0.4 and 0.3 respectively. The hardened properties tested for the HPC mixes were compressive strength at 7, 28, and 90 days, flexural strength at 28 days, and modulus of elasticity at 28 days. Maximum strength gains up to 15%, 38%, and 23% for compression, flexure, and elastic modulus were observed in ternary mixes compared to binary mixes. Stress-strain behaviour of ternary mixes indicates increased tolerance of stress for the least amount of strain in the specimens. Based on the experimental results, empirical relations were developed and checked with the existing codes and by earlier researchers. The durability properties tested for HPC were water absorption at 28 days, acid attack, and sulphate attack at 28, 56, and 90 days. Ternary mixes improved the pore structure of HPC, resulting in a 56% reduction in water absorption and a 34% reduction in compressive strength loss due to immersion in 5% H2SO4 at 90 days. The findings of the study endorse that ternary blending of SF and MK can improve the engineering properties of HPC, and a mix containing SF 10% and MK 10% is recommended for the best results.
Comparative Study on the Optimal Topologies
Összehasonlító tanulmány optimális topológiákra
The topology optimization is a leading tool in structural design. Due to the rapidly spreading need of the industry, commercial software are available in the market. Generally, these software are suitable for solving one subtask (preprocessing, postprocessing, stress calculation, etc.) but need some user manipulation to interconnect to one that is better for some other subproblem. This is the reason why we write a study on the available software and make suggestions on their usability. The purpose of this research is to briefly introduce selected software such as Rhino 3D, Grasshopper, Peregrine, Karamba, Galapagos, polyTop and PolyStress using topology optimization theory. Due to the demand to apply them for industrial applications, the additional goal is to make suggestions to make these software programs more user-friendly and to create algorithms to connect with software used in the industry, such as Consteel. This work also discusses the connected algorithms and optimization methods such as layout optimization by Peregrine, and topology optimization by polyTop and PolyStress. Several illustrative videos are provided as supplements. In addition to the text of this paper one can see demonstrations of the applications by the use of the provided YOUTUBE links.
Real Net Vault or Pseudo-Ribbed Net Vault?
Geometry, Construction and Building Technique of the Vault of the Reformed Church of Nyírbátor and the Nave Vault of the Franciscan Church of Szeged-Alsóváros
Valódi hálóboltozat vagy bordákkal díszített donga?
A nyírbátori ferences templom hajóboltozatának és a nyírbátori református templom boltozatának geometriája, szerkesztés- és építéstechnikája
In the present article, we revisit the question of the structural characteristics and building methods of two of the most famous Hungarian Late-Gothic net vaults, the nave vault of the Franciscan Church of Szeged-Alsóváros and the vault of the Reformed Church of Nyírbátor. Based on the data gathered by laser-scanning the two buildings, the geometric system of the two vaults, as opposed to the former state of research, differ significantly from each other. While the rib system and webbing of the vault of Szeged-Alsóváros have features characteristic of pseudo-ribbed net vaults and net vaults with webbing built with formwork, the vault of Nyírbátor is likely a real net vault structure with webbing built freehand. Furthermore, the rib system of the vault of Szeged-Alsóváros can be described by a single curved surface deductible from a circle segment, the rib junction points’ spatial positions in the vault of Nyírbátor are only describable by coordinates in the three directions of the space, not by an even surface. Based on the geometric descriptions, we also attempted to reconstruct the plausible building methods in both cases. Finally, we considered the results of the geometric analysis and the underlying construction ideas deduced from it and gave a new evaluation regarding the earlier reasonings for the strong building connections of the two churches in regard to the guilds and master builders.
Az esztergom-belvárosi kálváriakápolnák és stációk összművészeti jelentősége
The Overall Artistic Significance of the Chapels and Stations of the Calvary in Esztergom-Belváros
A hazai századforduló építészetének egyik kiemelkedő emléke az esztergomi belvárosi Kálvária-hegyen található összművészeti együttes, mely két kápolnából és 14 épített stációból áll. A több évtizedes elhanyagoltság után néhány évvel ezelőtt megkezdődhetett az értékek kutatása és mentése, az alsó kápolnát sikerült részben felújítani, ám a felső kápolna ez év elején már az összedőlés határára került. Közösségi és egyházmegyei kezdeményezésre és a város vezetésének segítségével az utolsó pillanatban sikerült megmenteni. A tervezést és felújítást megelőző kutatásaink olyan építészeti és művészettörténeti gazdagságot tárnak elénk, melyek országos szintű értékek, bemutatásuk és védelmük közös feladatunk. A restaurátori kutatások és értékmentések megtörténtek, és megindult a rekonstrukciós munka is. E cikk alapvető célja, hogy a szakma és a közösség megismerhesse, magáénak érezhesse ennek az együttesnek hazánkkal összefonódott sorsát, mely nemcsak közös múltunk tanúja, de közös jövőnk záloga is egyben.
Finding Groundwater in East and West
Comparing Methods of Finding Groundwater in Al-Karaji’s Treatise on The Extraction of Hidden Waters and Vitruvius’s Treatise on The Ten Books on Architecture
Földalatti vízvezetékek Keleten és Nyugaton
Al-Karaji A rejtőző vizek kitermelése és Vitruvius Tíz könyv az építészetről című traktátusának összehasonlító elemzése a földalatti vízvezetékek tekintetében
Hydraulic systems were built by ancient civilizations, notably the Persians and Romans, to deliver water to their residences where the water supply was scarce. Qanats were invented by the Persians to transfer water from aquifers to the surface, and aqueducts were built by the Romans to transport surface or underground water from its sources to distribution points in cities. Finding groundwater is a similarity between these two historical systems. This research compares ancient methods used by Persians and Romans to locate areas with abundant subsurface water. The oldest existing historical documents that recorded ancient ways of tracking groundwater, Al-Karaji’s treatise on qanats and Vitruvius’ treatise, were investigated with the qualitative content analysis method. As a result, historical means are divided into two categories in these two treatises including natural indications and practical tests. Natural indications consist of mountains and rocks, features of steppes, plants, vapours and dew, the whistles of the wind, and alluvial fans. An inverted container, a fleece of wool, an oil lamp, and a fire are instances of practical tests. Although these two treatises were authored over a ten-thousand-year interval and the structures of water systems differ, there are commonalities between ancient methods of tracing underground water.
On the Buckling of the No-tension Material Masonry Column
A húzószilárdság nélküli téglapillér statikai modelljéről
Masonry columns, subjected to eccentric compression, crack due to tension if the eccentricity is larger than the size of the core of the section. Previous studies have assumed that the cracks have so small spacing that the cracked tension side can be neglected during the analysis.
The critical load can be determined using this assumption. However, experimental experience has shown that the cracks have large spacing, approximately equal to one and a half times the cross-section height. Therefore, the crack-free parts between the cracks influence the lateral deflection and the critical load. Considering the above-mentioned phenomenon, we determined the elastic critical buckling load of the cracked masonry column.
Abstract
A railway on 4 m height embankment is being built in the south of Iraq. The railway alignment is extending on a compressible soil experienced impermissible settlement according to the results of soil investigation of the soil at the project site. A trial for reducing the settlement was done adopting sand piles. Nonlinear analysis was conducted to evaluate the settlement of soil before and after using the proposed technique.
The results indicated that without any improvement, the expected total settlement of the railway embankment on the compressible clay layer is 170.2 mm. By inserting granular piles of diameter 0.3 m, it was obtained settlement decreases to 88.7 mm with reduction being in range of ∼48%.
Abstract
The efficiency of using photovoltaic panels significantly depends on the climatic conditions and the power of the consumer. The evaluation of the efficiency of using the battery of the photovoltaic panel depending on the climatic conditions and the power of the consumer was carried out by the method of simulation modeling. A new type of storage battery allows to accumulate excess and compensate for the energy deficit due to the capacity of the batteries, and in case of their complete discharge - due to connection to other sources of electrical and thermal energy. The temperature field on the surface of the solar panel is constructed based on numerical simulation. The temperature ranges from +70.4 to +127.5 °C. In the main area of the panel, the heat flow ranged from 3,200 to 7000 W m−2.
Abstract
Speech scrambling aims to distort speech signals to prevent unauthorized listeners from understanding them, but conventional techniques are vulnerable to attacks. Therefore, more robust and secure speech scrambling algorithms are needed to ensure sensitive communication security. A proposed scheme uses a particle swarm optimization algorithm to generate a random key and optimize the level of noise in the scrambled signal, along with two transformations Multiwavelet and Arnold techniques to improve complexity and security. The proposed algorithm has been evaluated using various performance measurements and has demonstrated superior encryption performance than other similar audio encryption schemes with key space equal to 128 × 2.718. Further research and development in speech scrambling are essential to guarantee secure communication in sensitive contexts such as military and intelligence.
Abstract
With the development of society and economy, people pay more and more attention to thematic landscape architectural design featuring various cultures. Landscape architectural design is no longer only satisfied with the standardized, identical design style, but should focus on some specific cultural communication functions. In the thematic landscape architectural design, the use of cultural symbols can reflect the characteristics of the park. Through some research and practical design, the design method of using cultural symbols in landscape architectural design is summarized: from finding cultural elements to design language transformation.
Abstract
This study presents the frequency control of hybrid deregulated power system. The power system is supplied with appropriate system non-linearity's for practicality. A resilient model predictive control based two degree of freedom proportional integral derivative controller is designed. The Covid-19 based optimization algorithm is applied for optimization purpose. The impact of solar and wind on system dynamics are also examined. Further, the capacitive energy storage is also incorporated to check its influence. The distribution companies' participation matrix changes with market fluctuations, so the matrix is varied to check its impact. Lastly, sensitivity assessment is performed to analyze the strength of proposed controller optimized gains achieved under nominal conditions.
Abstract
The application of natural ventilation strategies in high-rise office buildings is considered one of the most promising trends to address high energy performance and enhance the indoor thermal comfort levels in interior office spaces. In this regard, this study attempts to assess the potential of natural ventilation strategies of a specific, previously investigated, envelope design of a high-rise office building located in a temperate climate zone. Different summer natural ventilation approaches were tested using the building energy simulation program IDA ICE 4.8, evaluating thermal comfort and energy demand. The findings indicated that considerable energy savings can be achieved, compared to conventional mechanical ventilation and air conditioning systems.
Abstract
Previous studies introduced the shiftability condition for successful gearshift, based on the dog clutch kinematics model containing several parameters. This study analyzes the effect of these parameters on the dog clutch shiftability. A method to study the impact of parameters is proposed. The influence of chosen parameter domains is shown. Their influence is recognized based on the shiftability map and the engagement probability. The initial relative position showed a periodic effect within one pitch region. The teeth number, axial speed, and the backlash positively affected the engagement probability, while the mismatch speed and the overlap distance showed a negative effect. The analysis showed lower limit values for the axial speed and the backlash but higher limit values for the mismatch speed and the overlap distance.
Abstract
The current research aimed to obtain mean pressure distribution over an air-inflated membrane structure using Computational Wind Engineering tools. The steady-state analysis applied the Reynolds-Averaged Navier-Stokes equations with the
Abstract
Due to the increase in earthquake activity in Iraq and Middle East during the last two decades, the study and understanding of probable destructive action and the best method to mitigate this effect became more important. So, many improvements and mitigation methods can be used. In this study, the use of permeation grout technique was adopted to prevent the existing soil condition in urban area by using cement kiln dust and bentonite clay. The tests were executed by using 1 g shaking table apparatus to simulate a sinusoidal motion (vibration) at specified different frequencies. The liquefaction phenomena were observed for loose saturated sand at 60 s, 25 s, and 10 s for 0.5 Hz, 0.75 Hz, and 1 Hz, respectively. After mitigation process, the soil liquefaction did not occur until 100 s, 60 s, and 30 s, for the same mentioned frequencies. Besides, the use of cement kiln dust decreases the liquefaction potential and increase the factor of safety.
Abstract
In this article, polymer-modified concrete was studied to present the effect of using additives on its mechanical properties. This will be achieved by employing a high-performance super plasticizing admixture that significantly enhances polymer-modified concrete mechanical capabilities. The study indicates that the polymer styrene-butadiene rubber (used increases concrete mechanical properties by 10% by weight. When the dosage exceeds 10% by weight of cement, the compressive, tensile, and flexural strengths of polymer-modified concrete are diminished. With the addition of a superplasticizer with a ratio of 1.2%, regular polymer-modified concrete compressive strength has increased from 34.3 to 42.9 MPa for a 10% polymer/cement ratio. Additionally, this superplasticizer enhanced the Material's flexural and tensile strength.
Abstract
Multimodal biometric systems have been widely implemented in a variety of real-world scenarios due to their ability to overcome limitations associated with unimodal biometric systems. This paper is focused on the combination of the face, ear and gait in a unified multimodal biometric identification system using handcrafted features. These approaches provide robust and discriminative features to solve the biometric problem. In this research, speed up robust features and histogram of oriented gradients approaches have been used to extract features from face, ear and gait. The extracted features are optimized using genetic algorithm and classified using Levenberg-Marquardt backpropagation neural network. The system performance is evaluated on constrained and unconstrained dataset conditions.
Abstract
This research paper exhibits the design of a V-shaped cantilever beam as a micro Energy Harvester (EH) having Piezoelectric (PZT) as its energy source for biomedical applications. PZT source based materials have the ability to convert the mechanical energy into electrical energy. Low-power biomedical devices mostly operate using electrical energy (i.e. batteries). But batteries are treated as a bio-hazard due to the massive use of biomedical applications. To overcome this toxic bio-hazard, the proposed PZT based V-shaped cantilever beam of micro EH can solve the limitations. To perform the experimental work, the cantilever beam design parameters - length, width and thickness have been considered and simulated using COMSOL Multiphysics to get the resonant frequency of 156.19 Hz which is lower than previous research work. It was observed that the obtained lower resonant frequency can be converted into AC voltage (mV) using PZT material. To convert the output AC voltage (mV) into DC voltage, a circuit of an Ultra-Low-Power (ULP) EH will be designed in LTSPICE software. Finally, the integration of the both V-shape cantilever beam and the ULP EH circuit will be implemented in PCB hardware to generate the output power (10 µW), will be stored in super-capacitor for biomedical devices-pacemaker.
Abstract
Side friction refers to combined variables indicating the degree of interaction between the activities and the traffic stream. The condition worsens when the transport demand and road-side activities increase, leading to inefficient traffic performance. This study has been focused on evaluating side friction impacts in terms of capacity and speed. Four links divided and undivided streets in Al-Najaf City, Iraq, were selected and on-street parking, pedestrian activities, entry-exit maneuvers, and temporary parking vehicles are considered as side friction elements. The results show about a 47% reduction in speed and about a 49% reduction in the capacity at a very high side friction level. Finally, a speed-predicting model has been developed for predicting the speed under side friction impacts.
Abstract
The multi-aquifer system of the Nubian aquifer in central Sudan hydrogeological system was simulated using a three-dimensional steady-state model. The goal of the study is to detect the effect of pumping on the groundwater flow and thus, the aquifer productivity. The conceptual model of the study area was built based on the available geological and hydrogeological data guided by geophysical survey. Processing MODFLOW numerical code was used to calculate the hydraulic head and water balance under the existing boundary conditions. The model accurately simulated the hydraulic head with a determination coefficient of 0.88. The calibrated model indicated that the change in storage is 0.56 m3/day indicating the study area constitutes highly productive zone and is recommended for groundwater developments.
Abstract
Real-time deformation measurements have the potential to be used in a wide range of civil and structural engineering applications. This paper introduces an algorithm that utilizes time-based photogrammetry to measure deformations in real-time. The hardware used in the algorithm consists of a camera and a computer that runs camera-control software and a MATLAB code. The code is responsible for detecting the approximate locations of the circular targets using normalized 2D cross-correlation and performing the sub-pixel measurement of the center by fitting an ellipse on the edges of the circular target. During an experimental load test of a concrete slab outfitted with Ringed Automated Detection targets, a series of images were taken at different loads. The coordinates of the targets were measured using the edge-ellipse operator, least-squares matching, and digital image correlation methods. The edge-ellipse operator has proven to be an effective method of measuring the image coordinates of circular targets.
Abstract
An experimental study was carried out on geo-polymer and reinforced concrete beams to evaluate the flexural behavior of the beams for the structural grade of M30 concrete. The results show that the geo-polymer concrete beams exhibit similar flexural strength when compared to reinforced concrete beams. The split tensile strength, stiffness characters, the energy capacity and ductility relationship were also found with satisfactory results. The deflection and the stiffness degradation at the salient stages were found to be similar and thus the geo-polymer concrete beams find a good alternative to reinforced concrete beams under flexural behavior.
Abstract
Recent studies showed a significant peak of the salt contamination in the Tisza River that exceeded ten times over the average level. The document summarizes the works performed on the investigation of ground displacement using multi-temporal satellite radar interferometry technique in Solotvyno mine located in Tiachiv region. Multi-temporal InSAR aims to identify coherent radar targets exhibiting high phase stability over the entire observation period and derives point data with locations corresponding mainly to the point-wise, man-made features. The middle area with no persecuted targets may correspond to the substantial physical changes of the surface caused by activities like mining or tunneling, adding, or removing structures or their components, and motion perceptible in one pixel.
Abstract
This project is the design of the tourism service station in the coastal park, which not only meets the basic functional requirements of the park service station but also reconfigures the station space with the regional cultural characteristics of Qingdao. The design process is mainly conceived in five aspects: locality, landscape, identity, symbolization, and diversification. It integrates the cultural characteristics of Qingdao coastal tourism with the park landscape to create a tourist rest space with diversified experiences. The purpose of this paper is to explore the interface between the stations' design and the various links of the cultural tourism industry chain. The project will be created as the “Window of Qingdao” in Baisha River Park.
Abstract
The digital economy is increasingly seen as an essential cornerstone in developing national strategies and industrial policies to enhance national competitiveness. On the other hand, a realistic assessment of digital readiness is essential for developing appropriate policies. In our paper, we group the countries of the European Union (EU) using three different methods applied to a dataset consisting of the four main dimensions of the EU's Digital Economy and Society Index (DESI) in order to identify Europe's main geographical “fault lines” in terms of digital readiness. DESI is a composite index aggregating several digitalization-related indicators to benchmark the progress of digital transformation in each member state. However, our methods aim not to rank countries but to identify groups of countries that are close to each other. The three methods used in the paper are partially ordered sets (poset), Tiered Data Envelopment Analysis (TDEA), and cluster analysis, known from multivariate statistics. The three types of clustering show a high degree of similarity, indicating the robustness of the results. Another research question relates to the extent to which the digital development of the EU Member States corresponds to the economic development of the countries and core–periphery relationships. While we can observe a high degree of similarity between the more and less developed clusters in terms of digital readiness and the groups that can be identified in terms of economic development and institutional quality, we also notice some peculiar exceptions (which could provide examples of best practices).
Abstract
In the event of a flammable liquid, gas, or vapor release the first step is to identify the type of outflow, which can fall into two categories sonic or subsonic. The two types of outflows carry different flow characteristics, which effect on the extent of the potentially explosive areas. In case of subsonic outflow, a short jet is formed without turbulent flow conditions at low velocity, which appears more concentrated around the source of release. With sonic outflow, a high velocity jet is formed with turbulent flow properties, which can extend further away from the source of release. The simulations examine the lower explosion limit of the flammable medium around the vessel where LEL20% or LEL40%. In addition, high temperature methane gas release was also presented.
Abstract
This study aims to identify and establish the long-term fluctuation of the low flow in the Hornád River. Hydrological data of five stations was obtained from the Slovak Hydro-Meteorological Institute and used for the analysis aims to show the trends of low flow and variability of the outflow during the period from 1973 to 2020. To determine low water levels, the limit value of the flow corresponding to the 70% and 90% from the flow duration curve along with the higher ones, determined on the basis of daily values for the entire multiannual period, was used. The observed patterns of low-flow changes on the example of a mountain river can be a reference point for many different studies and model simulations for other rivers in Slovakia.
Abstract
This article is related to investigations of the capture hoods of the local exhaust ventilation. The purpose of the research: to increase the zone of action of local exhaust hoods and reduce the amount of air removed. It is equipped with two barriers for air: ring and cylindrical. The empirical dependences for air velocity determination near the suction zone are obtained. Graphs, chart and three-dimensional image visualizations of removed air jet velocity near capture hood with barriers for air are designed. The reduction of production energy consumption, material, and ventilation system maintenance costs due to the correction of the design of the capture hood are the main benefits of the new solution.
Abstract
There is currently no accurate calculation procedure for determining the lateral-torsional buckling resistance of trapezoidally corrugated web girders. Therefore, a detailed investigation is performed in the frame of an experimental and numerical research program at the Department of Structural Engineering of the Budapest University of Technology and Economics. Based on the previous experimental results, a numerical model is developed to be used to determine the lateral-torsional buckling resistance by using deterministic method. The effect of flange size, corrugation geometry and boundary conditions are investigated. An improved design method is developed for the determination of the lateral-torsional buckling resistance of trapezoidally corrugated web girders.
Abstract
Analyzing the capacity of a signalized circular intersection is an essential aspect of traffic flow management. With the increased number of vehicles at the intersection, it is preferable to examine ways to increase capacity without altering the existing geometric features. A signalized circular intersection on the national highway in Győr, Hungary, between 47° 40′ 43.7988″ N and 17° 39′ 37.6668″ E is chosen and analyzed for capacity enhancement. The survey is conducted using 360-degree cameras. The PTV Vissim software is then used to construct a model based on the current and projected vehicle counts, as well as the current and proposed options. The result shows that it is possible to increase the capacity of signalized circular intersections without altering the geometric features.
Abstract
The current work discusses optimizing the structural design of reinforced high strength concrete rectangular sections under design loads. Using a least-cost design criterion and minimal design variables, an analytical approach to the problem is devised. A nonlinear mathematical programming format for the formulation of the problem is among the things that are demonstrated. To demonstrate how the formulation can be used in line with the ACI 318-08 standard, several typical cases are given. The outcomes are compared to those obtained from existing design practice. The ideal solution demonstrates unequivocally that significant reductions in the anticipated absolute costs of the building materials to be employed are possible and without making significant changes, this method may be expanded to address other portions.
Abstract
This study evaluates future changes in M-day minimum and maximum discharges in selected river basins of Slovakia, which have been divided into four groups, i.e., western, central, northern, and eastern Slovakia. Four types of data were available for the analysis, i.e., observed mean daily discharges, modeled mean daily discharges using the rainfall-runoff model, and simulated mean daily discharges according to the climate scenarios. The Indicators of Hydrological Alteration program was used to estimate the M-day discharges.
The results revealed an increase in the M-day minimum discharges in northern Slovakia. Eastern and Western Slovakia show a decrease in M-day minimum discharges and an increase in m-daily maximum discharges by 2100.
Abstract
Under the background of modernization, the continuation and development of historical and artistic values of ancient villages are faced with many difficulties, and corresponding theories are needed to guide practice. Taking Baojing Village in China as an example, this paper studies and expounds on the strategies for the protection and development of ancient villages, establishes a coordination mechanism for all parties and provides experience for the difficulties faced by this field. In the past, most Chinese ancient village literature studies focused on the characteristic value, formation, and evolution of historical and cultural villages. However, the research on the integration and utilization of resources in historical and cultural villages still needs to be further deepened.
Abstract
This paper deals with life cycle analysis of three wooden houses in terms of environmental impact indicators, construction, and operational costs. At the same time, indoor environmental quality of the houses is investigated. From the results achieved, it can be concluded that wooden house 3 shows the lowest emissions of CO2e/m2.year compared to other houses. Based on overall investigation wooden house 1 is the most advantageous. Concrete structures and mineral wool have the highest share of global warming potential. On the contrary wooden house 3 has the largest life cycle costs. Results of indoor environmental quality show that the permissible limits of the measured physical and chemical factors are not exceeded during the measurement.
Abstract
Due to significant industrialization, many countries have adopted the practice of industrial symbiosis, which involves utilizing the waste produced by one industry as a resource for another industry. The utilization of spent foundry sand (SFS), which is derived from the metal casting industry, poses a significant risk to both the environment and living organisms as a result of the existence of inorganic and organic substances. Nevertheless, this waste material can serve as a valuable resource for the construction sector. The utilization of SFS is significantly restricted due to insufficient comprehension of its concrete performance, despite its extensive range of applications. It is imperative to comprehend the behavior of spent foundry sand in concrete, particularly in relation to achieving a structure that is both strength-efficient and durable. The current study explores the usability of M-sand and spent foundry sand in self-compacting concrete. Reference concrete was produced by replacing river sand with 100% M-sand. M-sand was substituted with spent foundry sand in ratios ranging from 0 to 30%. Compared to the reference mix, SCC's mechanical and durability properties with 20% SFS were better. In comparison to the reference mix, SCC containing 20% SFS had higher mechanical and durability characteristics at 3, 7, 28 days, and 28 days, respectively. With 20% SFS, replacement showed better mechanical properties at all curing ages and better durability performance at 28 days of the curing period.
Abstract
The driver's eye height from the ground, as what drivers can see on the road, is essential for their safety and for avoiding road hazards. Using the statistical analysis of vehicles sample, the statistical parameters of the measured set of values were determined. A one-sample t-test was done to check whether the measured sample differs from the driver's eye height value specified in the Hungarian design guidelines. A new range of driver's eye height has been found, which is considered an update to the current value and might be applied in the upcoming road design. Parallel with the eye-height analysis, sight distances at vertical crest curves were modeled by AutoCAD Civil 3D. The minimum radiuses of the crest curves were defined for human eye height and for sensors of autonomous vehicles.
Abstract
This paper deals with the issue of spatial modeling of façade frame scaffolding, with the focus on developing a methodology for modeling subfloor components. A laboratory experiment on a standard scaffold base assembly consisting of two spans is described. Load tests were carried out, and additional measuring points were added to the measuring apparatus compared to the standard procedure. The nonlinear stiffness of the numerical models was derived from the measured value. Furthermore, planar models of the scaffold subfloors were created and validated against experiments. Finally, the paper proposes scaffold stiffness in the horizontal direction (perpendicular to the façade and parallel to the façade) that can be used in a full spatial member of the scaffold model.
Abstract
Control of OHS risks in the mining industry has been attracting increasing attention in recent years. Because of their great diversity in a complex system, hazards can be difficult to identify and classify, especially when system components interact. Risk cannot be managed successfully without comprehensive investigation of all its aspects. A coherent and integrated classification for identifying and categorizing all hazards is currently lacking in mining. We propose an integrated system classification of OHS hazards in mining based on our review of 44 studies retrieved using PRISMA. Considering Canadian and international standards, regulations and conventions, new hazard categories are proposed and hazard prevention is discussed from 12 perspectives: physical, chemical, biological, ergonomic, accident and psychosocial risks, as well as policy, legislation, management, design, geography, and uncertainty, with reference to each of the four phases of a typical mine life cycle, the hazards were shown in a portrait. This paper provides suitable categories based on rational data for creating a portrait in order to OHS hazards prevention in life cycle activity in mine.
Abstract
This paper aims to recognize the effect of material waste on cost increase in Palestinian construction projects. The study used questionnaire survey to achieve its objectives. The target population of the study are constructors and consultants involved in construction projects. The study also predicts the effect of cost overrun on material waste in some construction activities, namely: ceramic and brick works. The collected data were analyzed using statistical analyses. The study has established that among the various factors that affect cost overrun, experience in the line of work, conflicts among project participants, payments delay, and political situation are the key factors. While the analysis revealed that the main material waste factors are: poor site management, using untrained labors, rework due to workers' mistakes, selecting the lowest bidder contractor/subcontractor, and frequent change orders. Data from 55 building projects constructed in the West Bank between 2015 and 2020 were collected to test the relation between material waste and cost increase. Two mathematical models were developed: Model (l) links cost increase and waste in ceramic works. It indicates that if waste increases by 1%, the cost will increase by 1.07%. Model (2) links between cost increase and material waste in brick works. It tells that if waste increases by 1%, cost will increase by 1.25%. R square of value >0.7, for both models, indicates a strong linear relation between cost increase and material waste. This is the first study that predicts the effect of material waste on cost increase in Palestinian construction sector. The study encourages different parties related to construction projects to manage factors of cost overrun and material waste to enhance the sector of construction.
The Legacy of Soviet Monumental and Decorative Art (on the Example of Tselinograd, Republic of Kazakhstan)
A szovjet monumentális és dekoratív művészet hagyatéka (Celinográd, Kazah Köztársaság példáján)
The development of virgin lands (also known as tselina – previously uncultivated or unexplored areas of land, which have not been affected by humans and are typically located in rural or remote regions) has not only boosted the economy but influenced the development of art in Kazakhstan, particularly in Akmolinsk (in 1961 it was renamed Tselinograd, the current name of the city is Astana). Muralists M. Antonyuk and V. Tovtin made a significant contribution to the artistic and aesthetic image of Tselinograd. The purpose of the study is to identify the role of Soviet monumental and decorative art in designing the aesthetics of urban space and to substantiate its historical and cultural value. In this study, the features of stained-glass windows, marquetry, and monumental mosaics of Tselinograd were analysed. Their value as works of art was analysed, the specificities of incorporating national character are described, and their influence on the cultural development of the city is explained. The level of skill of the artists, including the ability to “embed” the artwork in the architectural image of the building is emphasised. The uniqueness of the monumental mosaics of the Soviet period is proved. Conclusions are drawn about their role as agitation. The need to preserve the works of monumental art for future generations is emphasised. This is an important part of the historical period – thoughtless “modernisation” of residential buildings, indifference to and devaluation of the artistic and cultural heritage of the Soviet past are not acceptable.
Abstract
High-performance internal combustion engines are subject to severe torsional vibrations which result from uneven gas and inertial loads. Fatigue damage occurs if the frequency of these undesired oscillations matches the resonance frequency of the crankshaft and the driven engine elements. This phenomenon can be avoided by the application of visco-dampers whose working fluid is high-viscosity silicone oil. Since silicone oil is exposed to a significant amount of heat load during operation, it is essential to calculate the temperature distribution in a relatively easy, quick, and cost-efficient way for lifetime estimation purposes. The aim of this article is to develop a reliable, fast, and accurate finite difference-based numerical method for steady-state thermal calculations for arbitrary damper sections. The developed MATLAB code calculates the temperature field of the damping fluid together with all components in a radial cross-section at given operational conditions. The accuracy of the developed thermal calculation method has been tested in a 3-dimensional – 2-dimensional two-step verification process by finite element and finite volume-based advanced engineering software in ANSYS environment. Furthermore, the original Iwamoto equation available in the literature has been updated to provide more accurate surface temperature results based on the simulations' outcome gained by the finite volume method.
Abstract
Effects of autonomous trucks' different lateral wander modes have been analyzed in this research using a dload subroutine. Two lateral wander modes, a zero-wander mode in which a truck is programmed to follow a predetermined wheel path without any lateral movement and a uniform wander mode, where the truck uniformly distributes itself along the lateral width of the lane, are used. European class A40 truck has been modeled in ABAQUS code. Results show that fatigue life of pavement increases by 1.45 times if a uniform wander mode is used, which corresponds to a decrease in fatigue life of 14 months if a zero-wander mode is used. In case of rutting progression, 40% acceleration of rutting happens under a zero-wander mode. In case of uniform wander mode, rut depth decreases by 1.25 times against the zero-wander mode.
Abstract
The aims of the work is to develop a numerical iced airfoil; quarter round forward ice was tested on NACA 4410 and NACA 0012 airfoils at zero and non-zero angles of attack, and Reynolds numbers equal to (2∙105, 2.4∙105) based on airfoil chord and Mach number 0.04. The two-dimensional steady-state momentum equations with the continuity equation have been solved applying a finite volume method to examine the turbulent flow over a clean and iced airfoil. The cambered airfoil NACA 4410 spends less power than the unsymmetrical airfoil at the same angle of attack. The reported numerical results demonstrated that for airfoil NACA 4410, the drag was increased by 40%, and the lift was reduced by 22%. However, for airfoil NACA 0012, the drag was increased by 43%, and the lift was decreased by 21%.
Abstract
Wastewater treatment systems are important sources of contaminants of emerging substances, including pharmaceuticals, and personal care products. Onsite wastewater treatment systems provide alternative solutions to centralized systems; although they are becoming increasingly popular, little is known about the effect of maintenance on their performance. In the current study, chemical and microbiological parameters in the effluents from two identical on-site wastewater treatment systems were analyzed, one being properly maintained while the other not maintained at all. Taxonomic profiles vastly differed from each other, and organic micropollutants are present at higher concentrations in the effluent of the non-maintained unit. The results highlight the importance of proper maintenance.
Abstract
Ethiopia's government proposes paving existing roads or building modern intersections in cities to reduce maintenance costs. An unimproved signalized intersection at 6° 51′ 47.9″ N and 37° 45′ 50.1″ E is selected for this research. Cost-benefit analysis is used to evaluate the proposed innovative approach to designing and implementing an intersection and to compare whether the new road projects will have an adequate return. This research suggests converting the current intersection into a signalized roundabout to calm traffic. Signalized roundabouts have a higher net present value and a modified internal rate of return than improved signalized crossing intersections. Considering the country's high inflation rate, three scenarios recommend using a signalized roundabout.
Abstract
Geological conditions are an important parameter on hydrological modeling that strongly affects runoff generation processes. They are not usually taken into account in the parameters of hydrological models, especially karst catchments, where water transfers through fissures, cavities, caves, and phreatic channels are regularly discarded in studies because of their nonlinear behavior and the variability of their typology. The study compared using of base flow separation methods in the conditions of karst catchments, where the reference base flow values measured are not available. The base flow separation was realized by various methods and the models available, including BFI+ and WHAT
Abstract
Chinese city growth has transitioned recently. Urban regeneration that fits local conditions has replaced rapid urbanization. City modernization and historic preservation often clash. Qingdao's ancient blocks need preservation and utilization to develop responsibly. This article aims to investigate the design interventions of adaptive reuse using in practical preserved projects. The study intends to give relevant participants interventions to consider while renovating historic districts to make theories, concepts, and plans guide, promote, and constrain the practice. It should also offer practical solutions to historic city renovation issues.
Abstract
This paper presents a novel approach for reconstructing the characteristics of non-punctual impact events on elastic plates by introducing multi-parameter optimization. The objective function is minimized using two heuristic optimization techniques, particle swarm optimization, and differential evolution, to reconstruct impact force characteristics. The force was regarded as taking the form of a uniform pressure over a part of the plate called the patch. The Maxwell-Betti theorem was considered to decouple the problem of localization and the time history of the applying unknown load. The approach based on heuristic optimization methods has been proven a performance to locate the impact zone. A comparison between particle swarm optimization and differential evolution was discussed.
Abstract
The presented paper draws attention to the need to adapt urban areas to the negative impacts of climate change, more precisely to the solution of extreme rainfalls and long dry periods. The topic of rainwater management is popular worldwide due to the worsening situation in the field of climate change. Extreme weather fluctuations and torrential rains stress the urban hydrological cycle. Adaptation measures are proposed that mitigate the impact of climate change in cities. These also include measures to retain water in the country. The paper focuses on drainage density analysis, runoff coefficients and impermeability analysis, and the selection of appropriate measures to reduce surface runoff.
Abstract
U-bending tests are the most common method to predict springback and are influenced by the process and geometrical variables in addition to material behaviour. It needs a numerical study at a high level with many variables to reduce try-out time and loop. In this study, the U-bending test of DC01 steel has been researched numerically and experimentally to govern the influential parameters. The numerical analysis was conducted using AutoForm-Sigma code. The die radius has an excessive influence on the change of flange angle than the punch radius, but the punch radius has the greatest influence on the variation of the sidewall angle. The coefficient of friction played a great impact on both flange and sidewall angle deviation and its influence grows stronger as the blank holding force increases.