Abstract

The paper presents a numerical calculation of the service life of concrete structures considering the effect of chlorides in the case of the material properties of structural lightweight waste aggregate concrete. Different amounts of fibres (0.0%, 1.0%, and 1.5%) and different values of compressive preloading (0%, 50%, and 100% of the ultimate strength capacity-USC) were considered. The subject of the research was the comparison of the influence of the constant diffusion coefficient and the time-dependent diffusion coefficient regarding the service life of the selected structure. Nine groups of material characteristics in combination with two numerical models are compared. A time-dependent diffusion coefficient and maturation coefficient, which were determined based on long-term monitoring (up to 461 days), were accepted for the numerical modelling. Thanks to time-dependent parameters, it is possible to observe the results of the theoretical service life of the structure and the influence of the mentioned factors. The analysed structure can be considered as the upper layer of an industrial floor in a chemical plant. It is important to determine the theoretical service life at which the structure shall be inspected or replaced. The results, in general, show that a higher amount of fibres reduces the service life as well as the preloading of the structure. An exception was a mixture with 1% of fibre loaded to 50% USC, which shows a lower diffusion coefficient than the specimens without preloading.

Highlights

  • For predicting or designing the service life of reinforced concrete structures, one dominant deteriorating mechanism is used, while the structures are always exposed to a complex simultaneous action of mechanical and environmental loads [1,2,3]

  • The paper presents a numerical calculation of the service life of concrete structures considering the effect of chlorides in the case of the material properties of structural lightweight waste aggregate concrete

  • Currently, for predicting or designing the service life of reinforced concrete structures, one dominant deteriorating mechanism is used, while the structures are always exposed to a complex simultaneous action of mechanical and environmental loads [1,2,3]

Read more

Summary

Introduction

For predicting or designing the service life of reinforced concrete structures, one dominant deteriorating mechanism (carbonation, chloride penetration, etc.) is used, while the structures are always exposed to a complex simultaneous action of mechanical and environmental loads [1,2,3]. To provide more realistic tests of the simultaneous action of both phenomena, RILEM TC 246-TDC [7] has developed a method to determine the service life of concrete exposed to the combined action of chloride penetration and mechanical load (compression or tension). A numerical calculation of the service life of concrete structures with respect to the action of chlorides [15] combinate with the material properties of SLWAC with different amounts of fibres and different values of preloading is presented. The analysed structure can be considered as a covering layer of a bridge structure exposed to chlorides from de-icing salts, or it is possible to consider the structure as the upper layer of an industrial floor in a chemical plant For both cases, it is important to determine the theoretical service life at which the structure shall be inspected or replaced. Nine groups of material characteristics, which differ in the amount of fibre and preloading, in combination with two numerical models are compared

Experimental Approach
Samples and Mechanical Properties
Electrochemical Test Method
Bulk Resistivity and Diffusion Coefficients
Numerical Analysis of Service Life Related to Chloride Increase
Results of Service Life and Discussion
Conclusions
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call