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L. Czarnecki and P. Woyciechowski

Abstract

The paper presents an idea of predicting durability of concrete structures with steel reinforcement under conditions of chloride and carbonation corrosion risk. Mechanisms of destruction due to steel corrosion in such conditions are shown. The recently elaborated model of carbonation and general model of chloride diffusion have been discussed. An algorithm of the rest service life time prognosis has been shown and options of its main stages realization have been done. An example of durability prognosis for pre-stressed hollow-core floor slab with upper layer of concrete and epoxy-resin coating has been given. This example confirms the usefulness of the described prognosis method and demonstrates its helpfulness in a structure management according to the standards of EN 1504 series

Open access

L. Czarnecki and D. Van gemert

Abstract

Innovation in construction is presented as a necessary aspect in the answer that the construction industry must provide to solve its negative impact on the environment. Original and innovative research is only part of the work to be accomplished. More important is the implementation of innovation in practice, where traditions are strongly rooted in society, and safety and long term reliability are required. Lessons from nature and study of durable examples handed down from the pasts serve as guidelines to innovative approaches that contribute to sustainability.

Open access

L. Czarnecki and J.J. Sokołowska

Abstract

The paper refers to the approach used in science, specifically in building materials engineering, assuming the possibility of material modeling, including modeling of the technical characteristics of building materials of various compositions as well as modeling phenomena/processes that occur during the use of materials and structures made from them. The authors analyze the merits of the approach of modeling in the context of compliance computational models to reality, consider the significance of the selection of the proper model (type of mathematical function, number of input data) which should be based on the knowledge of modeled material or phenomenon and later adequate verification of the model. The authors also underline importance of proper interpretation of results obtained by calculation. Misrepresentation may result in a misstated model of the studied phenomenon and lead to incorrect conclusions, which puts the researcher far from the truth, that he or she should always seek for.

Open access

L. Czarnecki and D. Van Gemert

Abstract

Science and engineering intermingle in the area of construction. Engineering works, often of great dimensions and design life cycle of many decades, have to be designed on a scientific basis since the safety of hundreds of users depends on their design. The task of scientific institutions is to define the construction performance within categories that correspond to the contemporary level of knowledge and technology. A construction appraiser who speaks out in a way that ensures unquestionable competence about the performance of elements and buildings (existing and under construction), should be convinced of the scientific basis of his opinions. A comparison of construction sections vs. basic requirements presents an archetype of the science of construction. A matrix of the science of construction reveals its multi-faceted nature; if related to time – the issue of durability has to be considered, and if related to the scale – the complexity. Defining the construction performance in terms of technical features is a constant search for a relationship between the material model and the usability model of a building. The construction industry uses a lot of “rules of thumb”, more than any other sector of technology. In the era of computer-aided design, CAD, and building information modelling (BIM), those rules of thumb remain invaluable verification tools.

Open access

L. Czarnecki and D. Van Gemert

Open access

L. Czarnecki and D. Van Gemert

Open access

R. Wang, J. Li, T. Zhang and L. Czarnecki

Abstract

Polymers are widely used in cement mortar and concrete modification due to their significant role in improving the overall performance of cement-based materials. Their physical interaction is well-accepted, while less attention is given to chemical interaction between the polymers and cement. Through a review of prior arts, chemical interactions are discussed and summarized in this paper. Various chemical interactions may take place between cement and different types of polymers. Understanding these chemical interactions will play an important role in clarifying the relationship between microstructure and macrostructure of polymer-modified cementitious materials. Authors expressed and proved the conviction that the organic-inorganic (Polymer-Portland cement) composite with some components chemically bonded, in parallel to the physical interaction, will be the next stage in concrete technology progress.

Open access

L. Czarnecki, M.P. Kaźmierkowski and A. Rogalski

Abstract

The h-index concept has been analysed in aspects of a contemporary tendency of parameterisation of everything and as the potential measure of the knowledge progress, which recognises individuals, institutions and Engineering sub-disciplines that best generate new knowledge. Considerations have been presented at the level of universality of knowledge which implies permanent progress and on the base of careful thoughts of the domestic experience. The h-nature of things has been described, and several axiomatic characterisations of the Hirsch index have been gathered. The mechanism how to increase the h-index has been presented. Some similarities between h-index and the journal impact factor (JIF) have been stressed. Also the universal role of H-index in ranking countries in all areas and in Engineering has been exampled in extended tables.

The Glänzel’s model which connects the h-index with two fundamental scientometric indicators: number of publications and the rate of citation, has been analysed. Following the Microsoft Academic Search, the lists of 15 top scientists from various academic disciplines and separately in Engineering have been composed. It has been found that the population of the best keeps basically the same relations between the h-index and a number of publication, and between the h-index and a citation number. However, even the best in Engineering should publish 2 times a year or more papers to receive the same h-index as top scientists in overall domains.

The h-index distribution of domestic Engineering sub-disciplines has been presented and analysed in statistic categories. The suitable hhistograms and the cumulative probability density function (CPDF) have been elaborated for 21 sub-disciplines and thereupon the Engineering sub-disciplines have been arranged into three clusters. It has been demonstrated that Engineering as the whole and Engineering sub-disciplines are underestimated, compared to other academic disciplines. The adequate normalisation factors have been suggested.

Several other conclusions considered the h,H-indices as the measure of the knowledge progress addressed to individual researchers and to collective, e.g., journals, institutions, organisations, countries, adequately have been written. The h,H-indices are the general measure of the position of the given subject (person or organisation) but cannot be universal.

Open access

L. Czarnecki and P. Woyciechowski

Abstract

The aim of the article is mathematical modelling of the carbonation process that has been based on results of research conducted both in accelerated and natural conditions. The article covers short characteristic of carbonation, its processes and effects. Also critical review of articles that concern carbonation mathematical models was included in the paper. Assuming the self-terminating nature of carbonation the hyperbolic model of carbonation was formulated. Such a model describes the carbonation progress as the process unlimited in time but with the restricted range in concrete depth that is limited by the value of a model asymptote. Presented results cover research on carbonation of concrete with a different water-cement ratio and different types of binders and duration times of early curing. Investigations have been conducted as accelerated (1% concentration of CO2) as well as in long-term exposures in natural conditions. The obtained results confirmed statistically that hyperbolic model is a well-founded approach when the modelling concrete carbonation process is concerned

Open access

Bogusz Wiśnicki, Leszek Chybowski and Maksymilian Czarnecki

Abstract

The article presents a method for evaluating the efficiency of port container terminals. The research was conducted for nine European terminals which use different handling technologies. The terminals have been divided due to the level of automation of transport processes. In the efficiency research DEA (Data Envelopment Analysis) method is applied, that was previously used in studies of the relative productivity in the industry. This method allows you to multicriteria process analysis based on the properly selected production system model processing input parameters on output. Conclusions from analysis can be a ground for making a decision on organizational or investment issues.