Construction Of Public Buildings Research Articles

MODELING OF A LIGHTWEIGHT FLAT FLOOR WITH VOIDS MADE OF PLASTIC BALLS

Formulation of the problem. Prefabricated monolithic construction in domestic and global practice in recent years has occupied a small share in the field of construction. A fairly large number of designs of prefabricated monolithic lightweight floors, as well as its individual structural elements, have been proposed. The use of lightweight floors in the construction of residential and public buildings can significantly reduce the consumption of materials and the dead weight of structures and increase the size of live loads and overlapping spans. Despite this, it cannot be said that effective design solutions have been found that can maximally satisfy the requirements of consumers, architects and builders. Based on this, a constructive solution for a lightweight prefabricated monolithic floor with voids made of plastic balls, quite effective from the point of view of construction and subsequent operation, was proposed and investigated. The proposed design solution for a lightweight prefabricated monolithic flat floor with voids made of plastic balls has less mass than solid floors and optimal use of material resources, namely the consumption of concrete and reinforcement. Therefore, research to determine the optimal design parameters of a flat lightweight floor with void formers made of plastic balls is relevant. The purpose of the article is to conduct numerous studies of the stress-strain state of the proposed design of a prefabricated monolithic floor with voids made of plastic balls. Conclusion. As a result of the research, it was established that it is rational to use hollow balls made from recycled materials as a material for making voids from balls in flat floors. Moreover, all studied floor options with spans of 6 m, 7 m, 8 m and void sizes made of balls with diameters of 180 mm, 315 mm and 500 mm meet the requirements of the first and second groups of limit states.

Comparative analysis of track damping effect of structure jointly constructed by subway tunnels and high-rise buildings

The joint construction of subways and other public buildings is a relatively newer type of construction. There is little research experience in the vibration characteristics and track damping design for this type of structure. In this study, a field test was adopted to conduct site measurement analysis on the vibration response of the joint construction project consisting of a subway tunnel and a building with typical frame structures. Numerical simulation methods were also adopted to, respectively, assume the use of ordinary tracks and steel-spring floating slab tracks for the subway for the situation where the Cologne-egg high-elastic fasteners were used on the track for damping purposes. Comparisons were performed to analyze the difference in the system vibration response between three different types of track. The results showed that the high-elastic fastener track and floating slab track both have a certain degree of damping effect compared with an ordinary track. Specifically speaking, the former has a damping advantage for frequency bands below 20 Hz, while the latter has the advantage for frequency bands above 20 Hz under the impact of the structural vibration characteristics for this joint construction. For this jointly construction structure, affected by the natural vibration characteristics of the structure, the natural frequency of the floating slab track is within 4 ∼ 10 Hz, and the similar vibration reduction effect can be achieved. This indicates that the structural vibration characteristic of the jointly constructed structure is an important factor determining the appropriate natural frequency of the floating slab track.

Exploration of establishing a unified carbon accounting method in the field of public buildings

Under the background of low-carbon development, the construction of green public buildings is an inescapable responsibility and mission. At present, there are relatively few studies on carbon emission of public buildings in China and there is a lack of unified and standardized carbon accounting methods. Therefore, based on the domestic research status, this paper reviews the research progress and trend of carbon emission in public buildings. Sorting out the common accounting boundaries and accounting scope in the field of public buildings; By constructing the interactive accounting method framework of public buildings, the process and method of carbon accounting are sorted out. Various points for attention in the process of accounting are clarified from data acquisition，data management, accounting analysis and other aspects. This study provides a theoretical framework for carbon accounting in the field of public buildings and lays a foundation for establishing a unified carbon emission accounting method system in the field of green public buildings.

Research on the application of prefabricated green steel structure in public buildings

The construction industry is a pillar industry to improve people's quality of life and promote social and economic development. It has the characteristics of high energy consumption and high pollution, which deviates from the requirements of green development advocated by people at present. In view of healthy long-term development, the building industry needs to take effective measures to reduce energy use. The components used in prefabricated steel construction projects are mainly processed in factory batches. After transportation to the construction site, they only need to be assembled in accordance with standard specifications and processes, which can shorten the construction period, reduce the generation of construction waste, and fully meet the development requirements of energy conservation and emission reduction. Therefore, prefabricated green steel structure has been widely used in the construction of modern public buildings. Firstly, this paper summarizes and analyses the development status and main types of prefabricated green steel structure. The practical application in public building construction is also discussed. It is hoped that the results can provide a valuable reference for the construction of similar projects.

An Assessment of the Values of French Colonial Townhouses in Hanoi Towards AMore Sustainable Conservation

As the capital city of French Indochina, Hanoi was well planned by the French and immensely invested in the construction of public buildings as well as houses. In addition to public buildings and villas designed in French colonial stylesthatshaped the so-called distinctive architectural heritage in Hanoi throughout the colonial years, a large number of townhouses built during 1920 -1950 which formed the cityscape of Hanoi in the first half of the 20thcentury should be noted. After nearly 70 years since the French army withdrew from the city, the number of French townhouses has considerably decreased. The remaining houses have shown that this is a real “treasure” that needs to be conserved because of their important values, not only in terms of urban architecture but also in cultural and historical aspects. However, a fact requiringspecial attention is that French townhouses in Hanoi -unlike French public buildings and villas -have not yet been recognised as heritage so that they can be keptto avoid the risk of deterioration or demolition under the impact of rapid urbanisation in the market economy. One of the main reasons for this negative urban development is that there has been no concrete or comprehensive rating system to assess the values ofthose townhouses whichwill closely correspondto their characteristics and contexts. Therefore, the authors -based on site surveys and by applying some appropriate methods such as expert consultations and case studies -have developed a full set of criteria to help evaluate those remaining townhouses as accurately as possible. This system can be used as a basis for asystematic assessment and classification towards a more effective conservation and even promoting the values of those townhouses with regard tothe development of a modern societyand in consideration ofsustainable heritage conservation as a mainstream in the world.

The significance of green spaces for protecting health of urban population

Green spaces (green infrastructure, green areas) are important components of urban environment. They are able to mitigate health outcomes of climatic risks, exposure to urbanization and adverse environmental factors. Bigger areas covered with plants should increase their accessibility for people living in cities. Analysis of the results reported in foreign studies that addressed influence of green spaces on public health proves that they promote physical activity by urban citizens, sports included, development of interpersonal communication and social interactions, improve mental health, and reduce prevalence of diabetes mellitus and other diseases. In some cases massive construction of residential housing and public buildings in Russian megacities and large cities led to reduction in green areas. The existing construction standards in Russia do not consider the recommendation of the WHO/Europe that requires accessibility of green spaces within a 15–20 minute walking distance and provision of 9 m2 of green spaces per person. Utility of green spaces for public health depends on evenness of their distribution. In case their distribution is mosaic, their benefits for public health and protection capacities are reduced. The present review shows the importance, needs and advantages of developing green infrastructure with continuous canopy that create potent green shading.

Значение зеленых пространств для защиты здоровья населения городов

Green spaces (green infrastructure, green areas) are important components of urban environment. They are able to mitigate health outcomes of climatic risks, exposure to urbanization and adverse environmental factors. Bigger areas covered with plants should increase their accessibility for people living in cities. Analysis of the results reported in foreign studies that addressed influence of green spaces on public health proves that they promote physical activity by urban citizens, sports included, development of interpersonal communication and social interactions, improve mental health, and reduce prevalence of diabetes mellitus and other diseases. In some cases massive construction of residential housing and public buildings in Russian megacities and large cities led to reduction in green areas. The existing construction standards in Russia do not consider the recommendation of the WHO/Europe that requires accessibility of green spaces within a 15–20 minute walking distance and provision of 9 m2 of green spaces per person. Utility of green spaces for public health depends on evenness of their distribution. In case their distribution is mosaic, their benefits for public health and protection capacities are reduced. The present review shows the importance, needs and advantages of developing green infrastructure with continuous canopy that create potent green shading.

Effects of low doses of gamma radiation on the human body

The purpose of this study was to investigate the incidence of additional cases of malignant neoplasms (MN) in a comparative aspect between the settlement living next to a radioactive waste disposal facility (RWDF) and the indicators of an environmentally clean area of the same territorial unit (region). Evaluation of radiation situation on the residential territory adjacent to the RAW disposal facility in settlement 1, and in settlement 2 (comparison settlement), as well as interpretation of the obtained data was performed in strict compliance with the requirements of regulatory documents specifying requirements to the research object. When performing measurements, the methodology described in the regulatory documents establishing these rules was used: MU 2.6.1.2398-08 "Radiation Monitoring and Sanitary-Epidemiological Assessment of Land Plots for Construction of Residential Buildings, Public and Industrial Buildings with Respect to Radiation Safety". The residents of the settlement 1 were found to be exposed to 3.7 mSv/year, i.e. 54.2% more than the average whole-year exposure dose received by the residents of the settlement 1 from natural background (2.4 mSv/year), which results in excessive risk of MHC development compared to the ecologically clean region. This indicates that excessive risk of MNS can occur even in conditions of radiation background within the considered safe dose of not more than 5 mSv/year. However, this risk is much lower than that from high doses of radiation. This makes it urgent to search for solutions that would allow implementation of the recommendations of the Chief State Sanitary Doctor of Russia regarding reduction of total radiation dose to 1 mSv per year or to develop measures allowing to neutralize harmful effects of radiation exposure on the human body.

Sustainability Impacts of Wood- and Concrete-Based Frame Buildings

The European Commission adopted a long-term strategic vision aiming for climate neutrality by 2050. Lithuania ratified the Paris agreement, making a binding commitment to cut its 1990 baseline GHG emissions by 40% in all sectors of its economy by 2030. In Lithuania, the main construction material is cement, even though Lithuania has a strong wood-based industry and abundant timber resources. Despite this, approximately twenty percent of the annual roundwood production from Lithuanian forests is exported, as well as other final wood products that could be used in the local construction sector. To highlight the potential that timber frame construction holds for carbon sequestration efforts, timber and concrete buildings were directly compared and quantified in terms of sustainability across their production value chains. Here the concept of “exemplary buildings” was avoided, instead a “traditional building” design was opted for, and two- and five-floor public buildings were selected. In this study, eleven indicators were selected to compare the sustainability impacts of wood-based and concrete-based construction materials, using a decision support tool ToSIA (a tool for sustainability impact assessment). Findings revealed the potential of glue-laminated timber (GLT) frames as a more sustainable alternative to precast reinforced concrete (PRC) in the construction of public low-rise buildings in Lithuania, and they showed great promise in reducing emissions and increasing the sequestration of CO2. An analysis of environmental and social indicators shows that the replacement of PRC frames with GLT frames in the construction of low-rise public buildings would lead to reduced environmental impacts, alongside a range of positive social impacts.

Hidden Cycles of Time in the Layout of Mesoamerican Ballcourts

ABSTRACT Thousands of ballcourts are known throughout Mesoamerica, as they are usually a main component of public architecture at mostly high-ranking archaeological sites. These buildings appear in different designs and layouts and were deeply tied to politics, religion, sacred belief, ritual, ceremonies, and sport. Considering that the construction of public buildings followed well-established architectural standards in accordance with social norms and religious concepts, I hypothesize that ballcourts were designed using closed polygon layouts with lengths and areas that displayed significant worldview numbers and time counts. Analysis of the layouts of 28 ballcourts from 17 archaeological sites indicates that Mesoamericans intentionally plotted short- and long-term annual and ritual calendric counts, and lunar and Venus synodic cycles. It is concluded that these buildings hosted public events to commemorate the completion or beginning of a new time cycle and to honor the related deities for whom they were built.

Bioclimatic zoning as a prerequisite for architectural and structural design, urban and area-wide planning

Introduction. Factors of nature and climate were analyzed using bioclimatic criteria of environmental assessments made in within the framework of urban planning during warm seasons. Territories of republics, located in Central Asia and southern Kazakhstan, were considered as southern specimen areas; they have both plain and complex mountainous terrains, and their climatic and bioclimatic conditions make them similar to equatorial countries. The author chose a method for assessing bioclimatic indices; they take into account the response of the thermal status of a person to the environment, which is a rele­vant task of architectural and structural design and area-wide planning in southern countries with hot climates.
 Materials and methods. This research project is based on a comprehensive methodology for studying, analyzing and summarizing meteorological factors, provided by local meteorological stations, and reference data from the leading research institutes of hydrometeorology. These data are further processed by the software package to identify specific small and large microclimatic and bioclimatic differences between large areas. The methodology also determines the degree of comfort of a thermal state of a person in urban bioclimatology.
 Results. A new area of research was identified to study the response of the thermal state of a person to the environment: the bio-climatological assessment of environments. Bioclimatic zoning of republics in Central Asia and southern Kazakhstan was performed to classify the bioclimatic conditions in these environments according to their livability, taking into account values of meteorological indices during warm seasons. Bioclimatic differences between territories, cities, and excerpts from area development documents were identified for the purpose of bioclimatic zoning and division into districts. Maps of districts were designed to make bioclimatic forecasts of territories for the purpose of architectural and structural design, as well as urban planning.
 Conclusions. The research is relevant for territories and cities with hot climates. Methodological fundamentals of bioclimatic zoning in Central Asia and southern Kazakhstan, coupled with classified bio-meteorological indices, will serve as a prere­quisite for purposeful and rational use of territories in the region; they will allow evaluating its recreational potential and planning the construction of residential complexes, public and industrial buildings and structures that ensure maximum comfort and convenience at minimum costs. The classification of bioclimates is presented; it is based on thermal characteristics of climates as well as responses from the human thermoregulatory system during excessively hot summer periods. These responses are needed to characterize the thermal state of a person during periods of greatest heat stresses and radiation loads.

«News of the Odesa city council» as a source for studying the history of the development of Odesa in the second half of the nineteenth and early twentieth centuries

The purpose of this article is to highlight the activities of the city authorities in the development of Odesa based on the materials of the «Izvestia Odesa City Duma», which in the late nineteenth and early twentieth centuries was the official journal of the Odesa city government. The article analyzes resolutions on the provision of land for the construction of public buildings, as well as publications and statistics on private construction. In addition, attention is paid to the issues of improvement in the city, namely, paving and landscaping of streets, laying of sewerage, lighting, etc. The analysis of the study showed that the materials of the «Izvestia Odesa City Duma» of the late XIX - early XX centuries require further study. After all, they allow not only to better understand the state of the municipal economy of this period, but also to study the activities of participants of city government at various levels to improve it.

Calculation of Energy Consumption and Carbon Emissions in the Construction Stage of Large Public Buildings and an Analysis of Influencing Factors Based on an Improved STIRPAT Model

Compared to general public and residential buildings, large public buildings are often difficult to construct and have a long construction period, creating greater construction energy consumption and carbon emissions on the one hand, while generating a large amount and many types of difficult-to-track process data on the other. As such, it is difficult to measure carbon emissions and analyze various influencing factors. By realizing the simple calculation of energy consumption and carbon emissions, as well as discerning the degree of influence of various factors based on the results of influencing factors research, it is of considerable practical significance to propose energy savings and emission reductions in a targeted manner. In view of the above, this work aimed to establish a more practical calculation method to measure energy consumption and carbon emissions in the construction of large public buildings, as well as to identify the multiple influencing factors related to energy consumption and carbon emissions during the construction process. To demonstrate the practicality of our approach, quantitative calculations are carried out for a new terminal building in a certain place and from the perspective of sustainable urban construction; thus, the driving factors of the traditional STIRPAT model are extended to seven. Based on the calculation results, a modified STIRPAT model is used to analyze the comparative study of impact factors, such as population and construction machinery performance, on energy consumption and carbon emission intensity. The results show the following: (1) The energy consumption value per square meter of this terminal building is 3.43 kgce/m2, and the average carbon emission per square meter is about 13.88 kgCO2/m2, which is much larger than the national average of 6.96 kgCO2/m2, and (2) the type of energy used in the construction process has the greatest degree of influence on energy consumption and carbon emission, and the local GDP, population factor, construction machinery performance specifications, and shift usage also show a positive correlation with the growth of total energy consumption and carbon emissions. Moreover, while the government’s continuous investment in energy conservation and environmental protection has reduced the total energy consumption and carbon emissions in construction, there is still considerable room for improvement. Finally, according to the results, we provide theoretical references and constructive suggestions for the low-carbon construction of large public buildings in the construction stage. Thus, the results of our study will allow policy makers to formulate appropriate policies.

Investigation of Uneven Implementation of Price Adjustment Clauses for Public Building Construction Projects in Arsi Zone of Ethiopia

Abstract: Public building construction projects have become a growing concern because they ensure the construction of hospitals, colleges, offices, universities, and other public buildings to overcome social issues. However, the Ethiopian building project's price adjustment provision was not properly implemented. The expected programs and uses of public building construction projects are hampered. Thus, this paper is aimed to establish a mitigation measures system to a prune problem at the grass route level to solve inappropriate price adjustment clause implementation. Focused group discussion, case study, and questioner survey are employed as data-gathering instruments in this study. In addition, the study was analyzed with the use of statistical package software and the Relative Importance Index, therefore, the results confirmed good decision making at the right time, a special contract condition must be drafted by experienced professionals, value engineering of alternate materials, paying the contractor in full advance, and regular cost monitoring is identified as mitigation steps for these issues. This research addresses how we can mitigate the issue of price adjustment clause misapplication in our country. More studies in more zones and regions are required to exert positive stresses so that the study's findings can be used to strengthen the national conditions of contract.

The Causes Influencing the Occurrence of Variation Orders in the Construction of Buildings

In the construction of buildings usually, problems occur because of the causes of change orders. The main causer of change orders is the owners, consultants, and contractors. These changes lead to conflicts among them which result in influencing building projects. Therefore, it is necessary to analyze the causes of change orders to reduce them and facilitate management. This paper determines the most critical factors that cause change orders from a different point of view, a consulting owner and a contractor, and a study of the reality of the management of change orders when constructing public buildings. The method employed in this research is a field survey using interviews with experts working in the construction of public buildings. Furthermore, the questionnaire was distributed manually and electronically. In conclusion, it would appear that the causes of change orders have been hierarchically according to the viewpoint of the owner, contractor, and consultant. The analysis leads to the following conclusions: Agreement of viewpoints owners, contractors, and consultants on the critical causes of variation orders were: ( the difficult financial situation - change material specifications to benefit the project - technical necessity - the nature of the site). Moreover, the point of view (owners and contractors) on the essential factors that cause change orders were: (preparing a bill of quantities is inaccurate - weak consultant guess ). In contrast, the consultant's point of view differs, as he considers these causes ineffective. It can be interpreted that the consultant sees these factors as insignificant because of his duty to implement the bill of quantities and designs. This research paper concludes that a complex causal relationship exists between the causes of change orders. The relative importance index (RII) for variation order causes varies among different groups' viewpoints (owners, contractors, and consultants).

A review of facilities management interventions to mitigate respiratory infections in existing buildings

The Covid-19 pandemic reveals that the hazard of the respiratory virus was a secondary consideration in the design, development, construction, and management of public and commercial buildings. Retrofitting such buildings poses a significant challenge for building owners and facilities managers. This article reviews current research and practices in building operations interventions for indoor respiratory infection control from the perspective of facilities managers to assess the effectiveness of available solutions. This review systematically selects and synthesises eighty-six articles identified through the PRISMA process plus supplementary articles identified as part of the review process, that deal with facilities' operations and maintenance (O&M) interventions. The paper reviewed the context, interventions, mechanisms, and outcomes discussed in these articles, concluding that interventions for respiratory virus transmission in existing buildings fall into three categories under the Facilities Management (FM) discipline: Hard services (HVAC and drainage system controls) to prevent aerosol transmissions, Soft Services (cleaning and disinfection) to prevent fomite transmissions, and space management (space planning and occupancy controls) to eliminate droplet transmissions. Additionally, the research emphasised the need for FM intervention studies that examine occupant behaviours with integrated intervention results and guide FM intervention decision-making. This review expands the knowledge of FM for infection control and highlights future research opportunities.

CALCULATION METHODS OF MONOLITHIC REINFORCEDCONCRETE STRUCTURES WITH POST-TENSION REINFORCING ROPES

In Ukraine, the use of "post-tensioning" technology, which consists in the use of monolithic structures with pre-tensioned ropes, is growing. Domestic construction practice uses the term "prestressed reinforced concrete structures with tension of cable reinforcement on concrete." Post-tensioning technology is a modern approach to construction that allows you to create monolithic structures with great strength and stability. Its main advantage is the use of pre-tensioned ropes, whichprovide additional structural strength.In this article, the main methods of calculating such monolithic reinforced concrete structures are presented and the experience of using this technology in the construction of public buildings in Ukraine is presented.The use of prestressed reinforced concrete structures with the tension of cable reinforcement on concrete has numerous advantages. They are more durable, resistant to deformations and able to support large loads. Such structures are used in the construction of bridges, overpasses, high-rise buildings and other industrial and civil structures.Ukraine is increasingly adopting modern and efficient construction methods, which is confirmed by the increased use of this technology. This helps to improve the quality and reliability of building structures, and also ensures optimal use of materials and resources.In general, the article aims to promote the popularization, study and development of monolithic structures with pre-tensioning of cable reinforcement on concrete, as well as the creation of an appropriate regulatory and legal environment for their design and construction. This will help improve the quality and safety of building structures and ensurefurther progress in the construction industry of Ukraine.

MONOLITHIC REINFORCED CONCRETE STRUCTURES WITH POST-TENSIONED ROPES

Currently in Ukraine the use of monolithic structures with post-tensioned ropes, which is better known as the technology of "post-tension", and in domestic construction practice - as post-tensioned reinforced concrete structures with reinforcement tension "on concrete". Ropes are mainly used as tension reinforcement in such constructions. 
 The article presents the main idea of post-tensioned monolithic reinforced concrete structures, presents the experience of using this technology in the construction of public buildings in Ukraine. Such designs have their advantages and scope. Sometimes such designs, in fact, have no other alternative. Therelevance of the study lies in the spread of the use of monolithic structures with post-tensioned ropes, the need to study such structures and the lack of regulatory documents for design. There are also examples of reinforcement of beams and slabs in slab structures and the main advantages of using posttension ropes in monolithic reinforced concretestructures on sites built in Ukraine.

Radiation survey of buildings and structures to be demolished

The article deals with the issues of normative and methodological support of radiation survey of buildings and structures to be demolished. It is noted that with the intensive growth of construction of dwellings and public buildings in large cities, former industrial territories with a significant number of facilities to be demolished are being included into the development zone. The radiation monitoring and sorting of industrial waste generated after the demolition of buildings is not feasible in practice. The expediency of radiation survey of buildings and structures to be demolished at the stage preceding their dismantling, as well as the need to develop and approve at the federal level the methodology of its implementation is substantiated. Recommendations for the assessment of radiation safety indicators of buildings and structures to be demolished are given. It is shown that if the value of ambient equivalent gamma dose rate in the buildings and structures to be demolished does not exceed 0.6 μSv/h, industrial waste generated after demolition of buildings and structures and containing only natural radionuclides are not a subject to any restrictions related to the radiation factor, since the value of effective activity concentration of natural radionuclides is guaranteed not to exceed 1500 Bq/kg and therefore the waste is classified as Category I in accordance with the Basic sanitary rules for the provision of radiation safety (OSPORB 99/2010).

Analysis of organizational features of the work of assembly cranes in cramped conditions construction

The possibilities of placing erection cranes in cramped conditions are considered. The factors for determining the type of crane and the conditions for its operation at the construction site are given. The principles of determining the conditions of tightness of the construction site in accordance with the regulatory documentation are shown. The possibilities of limiting the boundaries of the dangerous zone of the crane are considered. The designs of various cranes are analyzed from the point of view of their placement in cramped conditions. Data are given on the features of the use of bottom-slewing and top-slewing tower cranes in the construction of civil buildings of different heights. The possibility of replacing tower cranes with fast-mounted ones during the construction of low-rise public buildings is being considered. Recommendations are given on the placement of cranes of various designs, the definition of the technological sequence of the construction of the building.