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1

Reliable crack width prediction in EN 13084 & CICIND

Noakowski P., Harling A.

Archives of Civil Engineering

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2020

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Vol. 66, nr 1

3--23

EN

Cracks in concrete are inevitable but fortunately cracking enables the structures to get rid of its bending moment peaks. The reduction is due to the redistribution of the load induced moments and cut of the temperature-imposed moments. However, cracking becomes completely harmless if the crack widths are controlled properly by reinforcement. In this regard a method for crack width prediction is presented in this paper which thanks its reliability is widely accepted in the standards EN 13084, CICIND and DIN 1056.

2

Reliability assessment of existing concrete bridges

Marková J.

Journal of KONBiN

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2010

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No. 2-3 (14-15)

105-116

EN

The remaining working life of an existing reinforced concrete bridge is analysed considering the serviceability limit states of crack width. Two new models of crack width provided Eurocode EN 1992 and in the Model Code 2010 are applied. The probabilistic methods of structural reliability are used for assessing the crack width limits and remaining working life of existing concrete bridges. It appears that the initial reliability with respect to the serviceability requirements resulting from the original design of the bridge seems to satisfy the required target reliability level recommended in Eurocodes. However, the reliability index significantly decreases with the reduction of the reinforcement area due to corrosion.

PL

Pozostały okres żywotności istniejącego żelbetowego mostu został poddany analizie, w której szerokość pęknięcia przyjęto za graniczne kryterium użyteczności. Wykorzystano dwa nowe modele pęknięcia, których dostarczyły Eurocode EN 1992 i Model Code 2010. Probabilistyczne metody niezawodności strukturalnej zastosowane do oceny granicznych szerokości pęknięcia i pozostałego okresu żywotności istniejących mostów ze zbrojonego betonu. Należy sądzić, że początkowa niezawodność w odniesieniu do wymagań użyteczności wynikających z oryginalnego projektu mostu wydaje się zadowalać wymagany docelowy poziom niezawodności zalecany przez Eurokody. Jednakże w wyniku korozji współczynnik niezawodności znacznie maleje wraz z redukcją strefy zbrojenia.

3

Close to reality methods for the structural design of towers. The basics of the relevant standards for industrial chimneys

Noakowski P.

Architecture Civil Engineering Environment

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2010

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Vol. 3, no. 3

79-84

EN

Numerous large concrete chimneys were built in many different countries in the seventies and eighties last century. Unfortunately, the professional scene had to realize that those structures were very different in their forms, wall thicknesses and reinforcements. In addition to this many of them had been impaired by wide vertical through cracks decreasing their durability and wind bearing capacity. Both findings revealed dissatisfying situation that the existing chimney standards were mostly over safe and in some cases unsafe. Due to this, efforts were undertaken to develop modern, close to reality methods for the structural design of chimneys. These new design methods became popular and as such entered the most relevant European standards on chimneys.