This article presents the results of investigating the influence of tooth contact ratio in helical cylindrical gears on vibroactivity of the gearbox. Based on the measurements carried out on a laboratory test stand, time-domain and frequency-domain start-up characteristics of vibrations and acoustic pressure were determined, and vibroactivity was assessed for a gearbox in which 4 pairs of gears were successively mounted with different face contact ratios equal to, respectively, epsilon beta=1,001; 1,318; 1,574; 2,636.
This report describes the community involved in technology, organisation, and economics of theconstruction industry. The community includes mainly academics gathered around KILiW PAN, the Polish Academy of Sciences Section for Civil Engineering Projects. The results have been obtainedbased on the survey conducted in the period of 2007–2010. Some financial issues are presentedhere which influence the scope of the research underway and the didactic process. Some of theissues presented here comprise the subject matters of research, postgraduate studies, academicdegrees, as well as publications and international cooperation. Conclusions were presented in theform of suggestions in the field of research and teaching.
The article discusses the dangers arising from construction disasters. This phenomenon is the most serious effect of the risk that may occur in construction. I presented this on the basis of an analysis of all construction disasters that have taken place in Poland in the last twenty years. I made a detailed analysis of the events that occurred during the maintenance of building facilities, taking into account the reasons for their occurrence and the effects they cause. The aim of this analysis is to identify areas of risk in order to eliminate the hazard and, as a consequence, take appropriate actions to counteract this type of events. Unfortunately, one should be aware that despite technical progress building disasters cannot be completely avoided in our surrounding, but one must use the knowledge acquired on this basis to minimize their number.
The selection of a contractor is one of the most important among decisions made by the ownerof a construction. The application of the prequalification procedure enables the selection of themost competent tenderers. Various mathematical models are helpful in carrying out prequalificationprocedure. In the paper, some selected mathematical models are briefly characterized and modelbased on the theory of fuzzy sets is offered. The applied model takes into consideration theowner’s various objectives, as well as different evaluation criteria. The results of the sensitivityanalysis of the model are also presented. Part of a computer software applying an earlier presentedprequalification mathematical model is described.
Risks pertaining to construction work relate to situations in which various events may randomly change the duration and cost of the project or worsen its quality. Because of possible significant changes of random events, favorable, moderate, and difficult conditions of construction work are considered. It is the first stage of the construction risk analysis. The probabilistic parameters of construction are identified and described by using the design characteristics model of the structure and the construction technology model. The first describes the probabilistic properties of the structure execution's technology. The second describes the probabilistic properties of the works execution. Both models contain basic probabilistic data for scheduling, cost estimating, and risk assessment of the construction.
In the paper the topic of Building Information Technology BIM is investigated. It is new in Polish circumstances technology for construction and for building product industry, which contribute to change and develop level of industrialization. Especially challenge raising from the information and introducing IT technology into daily practice is considered to provide changes in construction branch of economy. In Poland there is the hot need of start to introduce BIM as the common technology for owners of assets, facility management, construction entities, design offices, administration officers and many other players relative to construction data and processes. BIM technology introduction, basing on foreign case studies, results in cost savings, control and time reduction of investment processes and some more advantages. The perspective of digital buildings, digital infrastructure, digital roads, digital railways and digital cities is outlined at the perspective of technology challenge, but simply transfiguration of many fields of personal everyday life, where digitalization is already present and with the question when it will be common in professional activity, particularly in civil engineering.
The paper shows methods of analysis and assessment of partnering relations of construction enterprises with the use of questionnaires, statistics, and fuzzy logic. The results were obtained from Polish, Slovak and Ukrainian enterprises. The definition of partnering in the construction industry indicates that it is a qualitative concept. By applying a scale in the questionnaire, and due to mathematical analysis of the data, the final research result, showing the level of partnering relations of construction enterprises, is rendered quantitatively.
According to UNESCO, in 2015, the sculpture as the artistic medium was third among financed public residency art programmes. Contemporary public art and cultural programmes across Europe were focused on finding a balance between cultural identity and cultural diversity among the communities. Therefore, aesthetics and function became a significant issue related to the exploration of participatory design on public sculpture. In this paper, an adopted model of Kurt Lewin’s force field analysis was used to explore the function of sculpture in the public space. The aim was to further evaluate inclusive design to answer the question: Does contemporary sculpture in the public space evoke a certain kind of group dynamic process?
The influence that general contractors and subcontractors have on the operation of a company is immense. Keeping this in mind, the authors have decided to develop and algorithm based on the analysis of partnering relations between construction companies that would select the best possible construction company for the purposes of cooperation. This algorithm, developed for a given construction company, is meant to support its decision-making system in the field of the selection of another construction company to cooperate with. The author has made references to earlier research, in which she had used the ELECTRE III method, and in which she bad analysed the possibility of applying the BIPOLAR method in order to solve the problem of the selection of a construction company to develop partnering relations with. The author provided an example of the calculations performed for a selection of construction companies.
This article aims to identify potential risk factors affecting the implementation and synchronisation of surveying and construction works during building and operation of roads. The task was executed on the basis of literature studies and experience. The article is an introduction to the research that has been conducted by the authors on the reasonably precise index of factors which one may deal with during the implementation of facilities of this type. The raised issue is crucial for financial and time reasons, but what is important in the roads construction - also for social ones, as prolonged traffic disruption adversely affects the environment.
The purpose of this article is to present the preparation of Project Risk Assessment Methodology and its mitigation in complex construction projects. The main text provides a summary of the approach, the method used and the findings. The conclusions have been drawn that the proper tools for quantifying risks have to be based on the criteria specific for mathematical statistic and probability or at least fuzziness. Function, which makes possible to categorize any risks into one of the five categories, is a combination of probability and the impact on one of the items: people and their safety or budget, cost, schedule and planning or quality and performance. An attempt was made to express numerically the relationship between risks impacts and their level of likelihood. Also, a method of associating the influence of projects risks impacts on the extent of the likelihood of project risk occurrence which makes possible to determine the direction and the strength of this relationship was presented.
Supplementing well recognised practical models of project and construction management, based on probabilistic and fuzzy events may make possible to transfer the weight of the change and extra orders assessment from the qualitative form to a quantitative one. This assessment, however, is naturally burdened with an immeasurable, subjective aspect. Elaboration of probability of occurrence in a construction project unforeseen building works requires application (in addition to the non-measureable, qualitative criteria) of measurable (quantitative) criteria which still appear during construction project implementation. In reimbursable engineering contracts, a random event described as an extra, supplementary building work has a random character and occurs with a specific likelihood. In lump sum contracts, on the other hand, such a random event has a fuzzy character and its occurrence is defined in a linear manner by the function of affiliation to the set of fuzzy events being identical with unforeseen events. The strive for quantitative presentation of criteria regarded by nature as qualitative and the intention to determine relations between them led to the application of the fuzzy sets theory to this issue. Their properties enable description of the unforeseen works of construction projects in an unambiguous, quantitative way.
This paper brings up the issue of population aging and its influence on designing and construction of buildings in Poland. It also touches the problem of adaptation of existing facilities to the needs of the elderly and the disabled. Moreover, current trends in Polish demographics and possible outlook for the next 45 years has been presented. The author presents the current legal state concerning rules and regulations on the aspects of adjusting the buildings and their parts to the needs of the disabled. Additionally, the dimensions and the areas of movement for the disabled as well as the primary functional and requirements for bathrooms have been described. In the next paragraph, a concept of Ambient Assisted Living with examples of sanitary equipment for use in residential buildings has been propose.
The construction industry in India is the country’s second largest industrial sector, after agriculture. The construction industry makes a remarkable contribution to the Indian economy and provides employment to a large number of people of Idia. Fire is a chemical reaction of a combustible substance with oxygen, involving heat and is usually accompanied by a visual flame or incandescence. Ensuring fire safety has always been a challenge to the stakeholders, i.e. building owners, construction companies, contractors and sub-contractors, and government employees due to the multiplicity of the factors involved and their complexity. There are various legal standards and requirements for ensuring fire safety on construction sites. The buildings are normally provided with firewalls during construction and these firewalls separate two structures or divide a structure into smaller portions to prevent the spread of fire. The lightweight construction and trusses are designed to support only their own weight. During a fire, if one fails, a domino effect happens and all fail rapidly within 5 to 10 minutes. Prolonged exposure to fire may result in structural collapse and injury or death of the occupants of the building under construction. Fire safety on construction sites is still in its primitive stages in India. There is a great necessity to improve fire safety on construction sites to protect construction workers and other occupants of the buildings. This study aims to design and implement fire safety systems for construction sites, thereby enhancing the standards to meet the system requirements at par with global standards.
This article shows incidents associated with the use of gas as an energy carrier. It presents selected incidents which have occurred in Poland and around the world in recent decades. Based on this, consequences of gas and air mixture explosions were analysed as well. The article presents the main causes of gas incidents which have taken place, as per instances which are similar worldwide. Incidents associated with the use of gas are not frequent, but at the same time very tragic as they often lead to illness or even death. In Poland, in the last twenty years, construction area disasters caused by gas explosions account for only 5% of all which have occurred, but the number of fatalities resulting from these cases is approximately 14%. The number of individuals injured reached 39% of all construction disaster victims. Considering all these facts, it is necessary to undertake wide preventive measures in order to increase safety in the use of gaseous fuels.
The model concept, as presented in this paper, is an original solution created by the author, and can be used as a proposal to build an innovative mechanism to increase the effectiveness of programming and implementation of the development policy, and improve the quality of functioning of a building research institute. The development management system included in this model is a set of actions targeting at the effective use of human and tangible resources, undertaken in a coordinated manner and leading to the achievement of previously established objectives. The market activity of building research institutes is directly or indirectly involved in construction projects, which translates into market mechanisms, such as innovation and competitiveness. In addition, it indicates the participation of a building research institute in the engineering of construction projects as a key to entrepreneurship and implementations.
The possibility of construction disputes can be reduced, but they cannot be avoided due to the uncertain and risky nature of the building industry. Conflicts between construction parties often have very unfavourable effects, such as cost increases, poor construction quality and time extension in the schedule. Lots of studies have been carried out in order to try and avoid these disagreements. However, there are no common resolution tools or techniques due to the improving conditions and scope of contracted works. Advanced methods and dispute reasons should be fully monitored and updated for the applicable solutions. This paper discusses the current major constructional dispute reasons in Turkey. The questionnaire method was applied within the scope of this study. The questionnaire documents were randomly distributed to 80 contractors to analyse major dispute reasons in Turkey. Analysis of the questionnaire results indicates that the major current dispute causes are poor quality of performed works, delays in progress payments, inefficient site management, poorly written contracts and design mistakes.