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1

Differences between DIN EN 1992-1-1/NA2011 guidelines and EN-1992-1-1:2004 standard with respect to the design of the minimum reinforcement and crack width from imposed deformation

Zych Mariusz, Jaromska Ewa

Archives of Civil and Mechanical Engineering

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2019

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Vol. 19, no. 3

627--638

EN

The paper provides a commentary on the differences in the approach to the mechanics of cracking, concerning cracks from imposed deformations and external loads, as defined in DIN EN 1992-1-1/NA (2011) compared with the EN-1992-1-1 (2004) guidelines. Theoretical assumptions of a detailed method of calculating crack width are presented, the assumptions resulting in, inter alia, a different way of determination of cracks maximum spacing in structural elements, satisfying or not satisfying the condition of the minimum degree of reinforcement. For certain cases, in the condition checking allowable cracks width, the necessity of taking account of cumulative action of imposed deformations and external loads is highlighted, while in EN-1992-1-1 (2004) guidelines imposed deformations and external loads are always treated as non-additive actions. Moreover, more detailed regula-tions for minimum reinforcement specification after DIN EN 1992-1-1/NA (2011), which are an inseparable element of cracking checking in the simplified method are also commented on. The paper identifies critical knowledge gaps and thus motivates researchers to close them. Moreover, the discrepancies between what we know and what we need to know are highlighted. This alerts other scholars to the opportunities for a key contribution. Finally, the conclusions for designers and researchers are presented.

2

Comparison of analysis specifications and practices for diaphragm wall retaining system

James A., Kurian B.

Studia Geotechnica et Mechanica

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2018

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Vol. 40, nr 1

21--29

EN

Diaphragm walls are deep embedded earth retaining structures. They also act as a part of the foundation. Geotechnical codes of practice from various countries provide procedures for the analysis of deep foundations. Not many standards are available that directly regulate the analysis of diaphragm walls. This paper compares the analysis of diaphragm walls performed using the foundation codes of different countries. Codes including EN 1997-1, BS 8002, BS 8004, BS EN 1538, AASHTO LRFD Bridge Design Specifications, AS 4678, AS 5100.3, Canadian Foundation Engineering Manual, CAN/CSA S6, IS 9556 and IS 4651 are chosen for the study. Numerical studies and calculations are done using the finite element software Plaxis 2d. Comparative study is performed based on the values of displacements and the forces developed. Study also evaluates the effect of differences in partial safety factors. The outcome of research emphasises the need for development of comprehensive analysis procedures.

3

EPC jako istotna technologia we współczesnej gospodarce

Szczepanik M

Logistyka

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2018

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nr 4

74--76

PL

Celem artykułu jest przedstawienie nowoczesnej technologii EPC oraz jej wykorzystywania we współczesnych przedsiębiorstwach oraz korzyści z tego płynących. Obiektem badania jest technologia Elektronicznego Kodu Produktu, który wykorzystując elektroniczny znacznik (tag), który odczytywany jest za pomocą fal radiowych, zamiast używania kodów kreskowych. Umożliwia to śledzenie i monitorowanie produktu w całym łańcuchu dostaw w natychmiastowy sposób bez konieczności posiadania tego produktu na linii wzroku. W ramach tej nowoczesnej sieci EPC możliwe będzie automatyczne rozróżnienie towarów oraz ich śledzenie na całej linii producent-konsument. System jest wykorzystywany na wielu obszarach m.in. w ochronie zdrowia, motoryzacji, transporcie i logistyce. Korzyści jakie za tym idą, to przede wszystkim zoptymalizowanie przepływu towarów, eliminacja braków produktów, racjonalna gospodarka zapasami i obniżenie kosztów przy rosnącym zadowoleniu klienta.

EN

The aim of this article is to present advanced technology EPC and its usage in modern enterprises as well as its benefits. The object of the study is Electronic Product Code technology which uses an electronic tag that is read by the airwaves, instead of using bar codes. It enables a company to track and monitor a product in the entire supply chain in an immediate way, without a necessity of having this product in the line of sight. Due to this advanced network EPC, it will be possible to distinguish goods automatically as well as to track them in the entire producer-customer line. The system is used in many fields, including health protection, motorisation, transport and logistics. The benefits of this system are primarily: the optimisation of the movement of goods, the elimination of the shortage of products, efficient inventory management and lowering the costs while rising customer satisfaction.

4

CHBDC buried structures: challenges in keeping pace with practice and innovation

Newhook J. P.

Archiwum Instytutu Inżynierii Lądowej

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2017

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Nr 23

21--33

EN

Soil-steel structures have been part of Canadian design codes since the 1970s. The inclusion in the Ontario design codes was necessary due to a growing use of flexible buried structures in practice. Since those early developments, the subsequent code committees have always strived to find the appropriate balance between the primary objective of providing design criteria that reflect the safety and serviceability requirements of the code and incorporating the significant practical experience of owners, engineers and industry. Each decade has seen innovations in products and applications as well as advances in research and numerical modelling. Editions of the code have acknowledged these changes, often in the non-mandatory sections, but have sometimes struggled to provide specific criteria. Instead it has provided general guidance or framework for design. Currently, many of the existing design clauses do not directly cover the applications of both flexible and rigid buried structures in regular use today. This paper describes the key updates being proposed for the Buried Structures section of the Canadian Highway Bridge Design Code. These changes are based on input from owners, engineers and industry describing the needs for current design and practice as well as a modem framework for permitting innovation. The major changes include areas such of finite element analysis, foundation design, conduit wall buckling and the use of flexible structures in cold regions susceptible to permafrost. These major changes will be discussed conceptually as final approval is still pending before inclusion in the 2019 version. The paper will describe some of the background and rationale for the proposals. Finally, the paper will discuss the challenges faced by the sub-committee in determining what should be included in the mandatory sections of the code or in commentary.

5

Buried flexible steel structures. Key problems of design code study

Madaj A.

Archiwum Instytutu Inżynierii Lądowej

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2017

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Nr 23

11--20

EN

Currently in Europe there is no uniform design code for buried flexible steel structures. In different EU countries there are different regulations concerning design methods, construction and control of such structures. This paper is an attempt at presenting the problems that need to be solved in order to prepare an uniform European Code. The thematic range of the proposed code is also outlined. The idea is based on the author’s own studies on buried flexible steel structures and design methods and codes from other countries, such as: AASHTO, CHBDC, ZTV and TRVK Bro 11. Concluding remarks contain a proposal of a committee consisting of several sub-committees that needs to be appointed in order to solve particular issues. This paper should be considered as a starting point for further discussion - it is not intended to be a “closed” proposal.

6

Validation of the fib 2010 and RILEM B4 models for predicting creep in concrete

Fanourakis G.

Architecture Civil Engineering Environment

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2017

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Vol. 10, no. 3

95--101

EN

Creep strain, a requirement of the concrete design process, is a complex phenomenon that has proven difficult to model. Although laboratory tests may be undertaken to determine the creep, these are generally expensive and not a practical option. Hence, empirical code-type prediction models are used to predict creep strain. This paper considers the accuracy of both the relatively new international fibModel Code 2010 and RILEMModel B4, when compared with the actual strains measured on a range of concretes under laboratory-controlled conditions. Both models investigated under-estimated the creep strain. In addition, the MC 2010 Model, which yielded an overall coefficient of variation (ωall) of 50.4%, was found to be more accurate than the RILEM B4 Model (with a ωall of 102.3%).

PL

Odkształcenia pełzania, których znajomość jest niezbędna w procesie projektowania, są złożone i trudne do przewidywania. Można przeprowadzić testy laboratoryjne w celu określenia pełzania, jednak są one generalnie kosztowne. W związku z tym w projektowaniu stosowane są modele empiryczne dostępne w normach. W artykule analizowano dokładność stosunkowo nowego międzynarodowego modelu pełzania przedstawionego w Model Code 2010 i RILEM B4, w porównaniu z rzeczywistymi odkształceniami pełzania mierzonymi w betonach dojrzewających w warunkach laboratoryjnych. Model MC 2010, który przyniósł całkowity współczynnik zmienności (ωall) wynoszący 50.4%, okazał się być dokładniejszy niż RILEM B4 (z ωall 102.3%).

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Przedmioty komputerowe na kierunku Budownictwo w stacjonarnym systemie studiów dwustopniowych

Cichoń C., Gilewski W., Łodygowski T., Pamin J.

Zeszyty Naukowe Politechniki Świętokrzyskiej. Budownictwo

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2005

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Z. 45

51-73

PL

W artykule zaproponowano przedmioty obowiązkowe i do wyboru w grupie przedmiotów komputerowych, dla stacjonarnego systemu studiów dwustopniowych na kierunku Budownictwo. Podano też propozycje powiązania tych przedmiotów z treściami wykładanymi w przedmiotach technicznych i zawodowych. Zwrócono uwagę, że przedmioty komputerowe są pewnym podsumowaniem i twórczym łączeniem treści innych przedmiotów, jak choćby matematyka, informatyka czy mechanika. W tym sensie stanowią intelektualną bazę świadomego inżyniera, który potrafi przy rozwiązywaniu problemów korzystać w miarę potrzeby z różnych sformułowań, modelowych uproszczeń i oszacowań służących podejmowaniu decyzji.

EN

In the paper the obligatory and elective computer subjects in the two-level system of education at faculties of civil engineering are proposed. Some suggestions of continued teaching of computational techniques in the following subjects are also given. It has been pointed out that the computational subjects are to a large extent a creative synthesis of other subjects such as mathematics, informatics and mechanics. In this sense they also form an intellectual basis of a conscious engineer who is capable of using different formulations and approximations according to the needs, and who can base his decisions while solving problems oil correct estimates.

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UMTS - przyszły system globalnej radiokomunikacji ruchomej

Rutkowski D.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2001

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nr 11

735-742

PL

Przedstawiono podstawowe charakterystyki systemu III generacji UMTS. Omówiono zagadnienia rozpraszania widma, ortogonalizacji sygnałów i modulacji, a także formaty pakietów zarówno w łączu w górę, jak i w dół w trybie dupleksu częstotliwościowego. Uwypuklono istotną rolę odbiornika RAKE w uzyskaniu wysokiej jakości odbioru pomimo zaników w kanale.

EN

In the paper basic characteristics of third generation mobile system UMTS have been presented. The spreading/channelisation codes and modulation as well as physical channel format on the uplink and downlink of radio interface in the frequency division duplex mode have been described. Some important problems of signal reception with the use of RAKE receiver have been emphasized.

9

Turbokody-granica marzeń

Hahn S., Jarkowski J.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2000

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nr 4

288-293

PL

Przedstawiono zasadę działania kanału transmisyjnego z zastosowaniem wynalezionych w roku 1993 turbokodów. Kody te pozwalają zbliżyć się do granicy teoretycznej przepustowości kanału przy transmisji w obecności szumu, wyznaczonej przez CIauda Shannona w roku 1948. Praca jest adresowana do szerokiego kręgu osób zainteresowanych, niekoniecznie specjalistów w dziedzinie kodowania. Dla specjalistów zamieszczono obszerną bibliografię. Opisano również w zwięzły sposób niektóre zastosowania turbokodów.

EN

The principles of digital transmission in the presence of noise using the recently invented (1993) turbo codes arę presented. The turbo codes have a performance in terms of bit error probability very close to the Shannon limit. In principle the paper is addressed to a large forum of nonspecialist in the coding theory. However a large bibliography Is addressed to specialists. A brief description of present and future applications is included.